Allelopathic tendencies of Impatiens glandurifera leaf extracts Sofia Mononen
|
|
- Peregrine Perkins
- 5 years ago
- Views:
Transcription
1 EUROPEAN JOURNAL FOR YOUNG SCIENTISTS AND ENGINEERS Allelopathic tendencies of Impatiens glandurifera leaf extracts Sofia Mononen Abstract Allelopathy is defined as the direct or indirect biotic interaction of a plant on another plant by releasing chemicals called allelochemicals into the environment. This release causes a detrimental effect on plants sharing the same habitat. Impatiens glandulifera is an invasive alien species that has no natural enemies in Finland, letting it spread from Southern Finland up to Lapland. The standard procedure of extermination involves cutting the plants so that they no longer sprout, leaving the leaves on the ground. If the leaves are allelopathic, they may still release allelochemicals through decomposition. The research question of the experiment was: Do different extract concentrations of leaf extract (0%, 20%, 40%, 60%, 80% and 100%) from Impatiens glandulifera have an effect on the germination and growth of Trifolium repens seeds? A bioassay was conducted to measure germination. The leaf extract concentrations were used to treat white clover (Trifolium repens) seeds germinated on petri dishes. The number of seeds germinated (72 hours) and the progress of growth (168 hours) were observed thrice a day. Results showed that seeds in high leaf extract concentrations (60%, 80% and 100%) had a significantly smaller germination percentage than leaves in lower concentrations (P=1.11 x ) 90.3% of seeds in 0% extract germinated whereas only 15.3% seeds germinated in 100% leaf extract. Growth and development of seeds was delayed (leaf opened only in 0% and 20% leaf extract). These results are in line with literature. Major issues included difficulties in extracting allelochemicals from leaves, the solubility of allelochemicals in water and the difference between field and laboratory studies. Minor issues included lack of variety in the biotype, systematic errors in the experiment and the lack of controlling osmotic potential of the extracts. 1 Introduction Allelopathy can be defined as the direct or indirect biotic interaction of a plant on another plant by the release of chemicals called allelochemicals from different parts of the plant into the environment (Rice, 1984). The chemicals can be released from the plant through different mechanisms such as volatilization, leachation, root exudation and decomposition (Anaya, 1999). The release of these chemicals causes a detrimental effect on plants sharing the same habitat as the allelopathic plant, therefore it can be said that allelopathy has an effect on plant ecology, such as growth, diversity, structure of community and productivity. The word allelopathy comes from two Greek words allelon meaning mutual and pathos meaning harm. As many allelochemicals are toxic to plants, research has been conducted to investigate the use of allelopathic plants as natural, environmentally friendly herbicides (Narwal, 2010). The ecological effect of allelopathy is vast. It is known that allelopathy can have a direct or indirect effect on plants but it also can have an effect on other organisms 15
2 MONONEN through changes in the soil properties and nutrients (Kruse, 2000). The diversity of different plant species can be reduced and the development of plants resistant to allelochemicals can result in genetic variation of plants (Kruse, 2000). Allelopathy plays an important role in biodiversity as the dominant species may limit the population of another species therefore regulating the density of the plant community. Impatiens glandulifera belongs to the Balsaminaceae family and originates from the western Himalayas at altitudes ranging from 1800 to 4000 metres, hence its common name Himalayan balsam (Helmisaari, 2010). It was introduced to England in 1839 from where it spread over Europe, becoming an invasive alien species. It has formed into an aggressive weed species due to its violent seed dispersal mechanism: the seed pods explode when touched, scattering seeds up to 5 metres away (Willis, 2004). I. glandurifera is continuing to expand in Europe and North Europe and is causing problems for ecosystem management (Kollman, 2004). According to Beerling (1993) the plants distribution in Southern Finland is controlled by the stretch of the growing season. This means that the species might spread further northwards with increasing global temperatures. According to the city of Helsinki Environment Centre, any large areas of I. glandulifera should be cut down before the seed pods are developed (City of Helsinki, 2012). The importance of this investigation is crucial: if the leaves are allelopathic they may decompose and release allelochemicals into the soil, preventing germination and growth of new species into the area. Trifolium repens is commonly known as white clover. In Finland it is widespread all around the country, with the exception of Northern Lapland (Lampinen, 2009). It is considered native to Europe, Northern Africa and Eastern Asia (Hannaway, 2004). It has been seen to grow from the Artic regions such as Russia, Canada and Finland to subtropical areas such as Australia and South America (Williams, 1987). It requires surface moisture and it can tolerate flooding, which means it can survive in a similar environment to that of I. glandulifera. The seed is small and germinates rapidly which made it suitable for this investigation. In this study, the allelopathic tendencies that leaf extracts of I. glandurifera (himalayan balsam) had on the germination and growth of T. repens (white clover) seeds were investigated. The research question was: Do different extract concentrations of leaf extract (0%, 20%, 40%, 60%, 80% and 100%) from I. glandulifera have an effect on the germination and growth of T. repens seeds? A bioassay to measure germination was conducted: germination in this context meant when the radicle protruded more than 1mm through the seed coat. The development of growth through several stages (germination and radicle growth, root hair development, cotyledon emergence and opening of the leaf) was also observed to see if the extract had an inhibitory effect on growth as well as germination. The results may be altered by the solubility of allelochemical, the amount of chemicals in the tissue and environmental conditions around the plant. This will be dealt with in discussion. 16
3 ALLELOPATHIC TENDENCIES OF IMPATIENS GLANDURIFERA LEAF EXTRACTS 2 Method Impatiens glandulifera was chosen as the target species due to its invasive nature as invasive alien species. Trifolium repens was chosen as the seed due to its small size and quick germination rate. 400g of leaves were collected in Leppävaara near Helsinki in the beginning of the summer of 2012 (June-July). The plants were on the bank of a stream on the edge of a road and the leaves were all estimated to be the same size (around 20 cm in length) and reaching maturity (some individuals had already flowered). As the locations of allelochemicals differ from plant to plant, the allelopathic plant may show no allelopathic tendencies unless the correct location is found. The leaves were chosen for this experiment as a previous study by Vrchotová, Šerá and Krejčová (2011) used a similar experimental method to see that the leaves of I. glandulifera inhibited germination of Leucosinapis alba and Brassica napus seeds. It should also be noted that plants make allelochemicals at different times of the year depending on what stresses they are exposed to, such as lack of water (Rice, 1984). The more stress; the more allelochemicals produced. Therefore all leaves were collected at the same time in the summer. The summer of 2012 in Finland was wet and rainy, which is suitable conditions for Himalayan balsam to grow in. Therefore it could have been that the plant was not under any stress and did not need to produce a large amount of inhibitive chemicals. For each trial, 40 g of I. glandulifera leaves were dried in a 60 C low-heat oven and ground using a mortar and pestal. This was done to extract the allelochemicals from the leaves and because compounds in the leaves are not uniformly distributed. Different methods of extraction are available, but water was decided as the best as it most closely depicts natural circumstances. The leaves were then placed into a 1000cm 3 beaker with 470 cm 3 of distilled water and placed onto a magnetic stirrer to be mixed. Distilled water was used, as it does not contain any ions that might decrease the level of allelochemicals (due to lack of stress). Clingfilm was placed on top of the beaker and the solution was heated to 50 C for 10 minutes to exert stress on the plant to increase allelochemical production and release the allelochemicals into the water solution. 10cm 3 of water was added due to any loss of water as water vapour due to evaporation. This saturated leaf solution was left overnight in room temperature on the magnetic stirrer and filtered twice before the different concentrations were made. The filtering was done to prevent any plant material from being in the extracts. The ph of the solution was recorded at this point and found to be slightly acidic. The independent variable of this experiment was the range of leaf extract concentrations. The extracts (0, 20, 40, 60, 80 and 100%) were made by adding distilled water in different volumes to the saturated leaf solution. The 0% control had no leaf extract in it whereas the 20% concentration consisted of 20% leaf extract and 80% distilled water and so forth. The exact volumes used to make the different concentrations can be found in appendix I. When distilled water was added, the solution turned brown. All extracts ranged from a dark brown (100%) to a light orange colour (20%). 17
4 MONONEN Each concentration was placed in a small, labelled plastic container and stored in a fridge when not used. It was noticed that though the extracts were filtered twice, after a few days of being kept in a fridge the extracts formed layers with a greenish substance at the bottom of each pot. Each extract therefore had to be shaken before being pipetted into the dishes. For each repetition, 6 petri dishes were lined with 3 filter papers and covered with 4 cm 3 of extract. All Finnpipette tips, petri dishes and filter papers were unused to prevent distortion of results. The rest of the equipment was washed with deionized water and soap. 30 T. repens seeds were placed into each dish using tweezers and the lid was placed back on to prevent evaporation. The seeds were germinated in a dark environment at 25 C. The seeds used were Huia which had a germination rate of 90% and consisted of 99% pure seeds. Every 6 hours 0.5 cm 3 of extract was added to the petri dishes. When adding 0.5 cm 3 of solution to each dish it had to be swirled to evenly distribute the solution to each seed. The number of seeds germinated was recorded every 6 hours for 72 hours and the growth of the seeds was observed for 168 hours. After the first day of germination the seeds swelled to double their size. The seeds osmotic potential was therefore considered to be equal. For the second part of the experiment the seed growth was monitored for 7 days. The four stages of growth were marked: 1. germination and radicle growth 2. root hair development 3. cotyledon emergence 4. opening of the leaf Throughout the experiment, the progress at which each concentration grew was noted. 3 Results 3.1 Seed germination The number of Trifolium repens seeds germinated was reported three times a day (Δt=±0.5h). Table 1 presents the final number of seeds germinated after 72 hours. The germination was found to vary from 15.3% ± 0.6% to 90.3% ± 0.6%. The least number of seeds germinated in the 100% leaf extract condition whereas the most number of seeds germinated in the control (0% leaf extract). In table 2, the mean percentages of the trials can be seen along with the standard deviation of each percentage. Graph 1 presents the mean germination of white clover seeds in different concentrations of Himalayan balsam leaf extracts over a period of 72 hours. For this graph, the mean values from all 10 trials at each concentration and time were calculated and graphed. The curve of growth is similar for each concentration though a slight crossing of 40% and 60% concentrations can be seen at 36 hours. Based on a statistical procedure called ANOVA (Analysis Of Variance), the variances of each condition varied from each other (ANOVA is similar to a t-test but 18
5 ALLELOPATHIC TENDENCIES OF IMPATIENS GLANDURIFERA LEAF EXTRACTS Table 1 The number of 30 T. repens seeds germinated at different concentrations of I. glandulifera leaf extract after a period of 72 hours in a dark environment at room temperature Trial Concentration of I. glandulifera leaf extract (%), (Δc=±0.6%) Table 2 Mean percentages and standard deviation of number of T. repens seeds germinated in different concentrations of I. glandulifera leaf extract Concentration of I. glandulifera leaf extract (%), (Δc=±0.6%) Mean (%) SD for more than two conditions). Microsoft Office Excel was used together with a StatPlus add-on to find the value of p. This value was seen to be Therefore there is a significant difference between two or more conditions (p= , thus H 0 = rejected). A t-test was also performed between 100% leaf extract and the control (0% extract). There was also a significant difference between these two conditions as p = Therefore we can be certain that two or more of the results obtained are significantly different from each other. 3.2 Monitoring of growth speed Seed growth was monitored for 7 days. Out of all the concentrations 0% and 20% were the only two concentrations to reach stage 4 opening of the leaf. 100% and 80% only reached stage 2: root hair development (see table 3). This showed a major difference not only in the growth, but also in the speed of growth in the 19
6 MONONEN Graph 1 Mean germination of T. repens seeds in different concentrations of I. glandulifera leaf extracts over a period of 72 hours. 30 Mean number of seeds germinted ( max. 30 seeds) Time (hours) 0% 20% 40% 60% 80% 100% Table 3 Seed growth raw data table of all petri dishes over a period of 7 days Time (h) Concentration (%) (Δc=±0.6%) Key: Germination and radicle growth; Root hair development; Cotyledon emergence; Opening of leaf different concentrations. As this was only monitored for 7 days, it could be possible that all concentrations would have reached stage 4 but after a long period of time. However, it could also be possible that the strong leaf extract prevented the growth of the seedlings and altered the seed in a way in which the cotyledon would not emerge. It was also noticed that growth was much slower: after 3 days 0% and 20% concentrations were already at stage 2 whereas 100% and 80% had only just germinated. This data shows us that there is a possibility that the same chemical that results in the slight inhibition of germination in higher concentrations may also delay the growth and hinder the development of the seeds. Further study should be done in order to see whether the leaf extract slowed the growth of the seeds or inhibited the growth completely. 20
7 ALLELOPATHIC TENDENCIES OF IMPATIENS GLANDURIFERA LEAF EXTRACTS 4 Discussion The experiment conducted gave results that showed that higher concentrations of Impatiens glandulifera leaf extract slowed and inhibited the germination and growth processes of Trifolium repens seeds after 72 hours (see graph 2). The higher concentrations did not, however, completely inhibit germination as was reported in previous studies (Vrchotová, 2011). This could be due to several reasons, for example the growing conditions of the plant, the method of extracting the allelochemicals and the small systematic errors in the experiment. The site from which the leaves were harvested was heterogenous and almost all I. glandulifera plants were not yet fully mature. The plants were on the bank of a small stream called Monikonpuro. The leaves chosen were all around 20cm long though were harvested from all parts of the stem. The summer of 2012 in Uusimaa region of Finland was wet and rainy, which is suitable conditions for I. glandulifera to grow in. According to Finnish Meteorological Institute, the monthly precipitation in June 2012 almost doubled the long-term average (Finnish Meterological Institute, 2012). Therefore it could have been that the plant was not under any stress and did not need to produce a large amount of inhibitive chemicals to compete against other plants with. This could be the reason why the 100% leaf extract concentration did not fully inhibit the growth of the T. repens seeds (as seen in graph 1 and 2). The amount of chemicals in the tissue also varies: it could be possible that the leaf did not carry high enough levels of allelochemicals to exude a strong inhibitive effect on the seed. Another reason as to why a stronger inhibition of germination was not obtained could be due to the solubility of the allelochemicals in question: it could be possible that ethanol should be used instead to extract the non-water-soluble chemicals. Allelochemicals can be polar and non-polar, and if a non-polar chemical is in question a non-polar solvent should be used to extract it. However this would not be appropriate to germinate seeds with, as water is used in nature to germinate seeds and the use of ethanol may cause other changes in the seed and the solution. Systematic errors in the experiment included the inability to spread water evenly in petri dishes, the seeds moving around the petri dish when water was added, the seeds being small so germination was tricky to measure and the extracts not keeping long. A pot experiment could be conducted which would eliminate the problems of seeds moving and water not spreading evenly. By conducting a pot experiment it is also possible to measure growth in a more substantial manner. Using this alternative method, it would be possible to see if I. glandulifera leaf extracts slow down the progress of growth or prevent the cotyledon from emerging as seen in this experiment (see results section 3.1). However, reasonable results were obtained from this experiment, which means that systematic errors did not affect the results largely. It was seen that in some trials the seeds in the 20% leaf extract concentration germinated faster and grew faster than the control (see raw data table trial 7). The reason why the extract may promote the seeds to germinate may be due to the nutrients from the leaf extracts in the allelopathic plants. As distilled water contains 21
8 MONONEN no nutrients, the 0% control only used pure water to germinate. The seeds in the 20% trial may have obtained enough plant matter from the crushed leaf extract to obtain nutrients that the 0% trial did not obtain, but too little allelopathic chemicals for any inhibitive effect to be shown (a similar phenomenon can be seen in graph 2 the overlapping of 40% and 60% concentrations). The lack of controlling osmotic potential means that allelopathic effect can be overestimated (Marambe, 1998). As Bell reported in 1974, extracts made from crushed plant tissue may cause suppression of germination on its own due to the high osmotic potential. This factor was not controlled but it was observed that most, if not all seeds swelled at the same rate. However in future experiments the control should be altered to have the same osmotic potential as the extracts. Advantages to the study performed included the ability to complete several trials in a short period of time, the short germination time resulting in less possibility of pathogens to contaminate the samples, possibility of obtaining both qualitative and quantitative data and the ability to regulate several controlling variables in a controlled environment. This helps establish a cause-and-effect relationship between the independent variable (the different concentrations of leaf extract) and the dependent variable (the number of seeds germinated). Results showed that stronger concentrations of I. glandulifera leaf extracts affect the germination and growth of T. repens. However, if we evaluate this experiment on a wider scale, these results may not be evidence of I. glandulifera being allelopathic. Even though the seed germination was inhibited in higher concentrations of leaf extract, this does not mean that the chemicals will affect fully mature plants. For example, the allelopathic effect of an invasive species may reduce over time as the native species adapt to the chemicals and become resistant. The effect of an allelochemical on plant growth should be evaluated with regard to both the presence of the compounds and the influence of other chemical and physical conditions in the environment. Many of the allelopathic chemicals are reactive and could easily be transformed through extraction and analysis. In nature, their allelopathic effect will depend on the environment in which they are released into. How soluble they are will affect how they will move in the soil, the vapour pressure will affect how volatile they are and their structure will affect how degradable they are (Cheng, 1992). The way the chemicals react in the soil also depends on several factors such as ph, particle size and oxidation state (Cheng, 1992). The allelopathic effect of an invasive species may reduce over time as the native species adapt to the chemicals and become resistant to the chemical. It must also be remembered that the affected plant can be capable of defending itself from the allelochemicals. For example, the plant can exude enzymes that break the chemicals into non-harmful substances (Cheng, 1992). This means that the plant may not express any allelopathic properties on the other plants even if it contains allelopathic chemicals. It is insufficient to say that a plant will be influenced when it is mature because it inhibited seed germination. Field studies are difficult to replicate in a laboratory. To study allelopathy, one must go into the field to study how the mechanism works. Competition and allelopathy may work together and it is difficult to separate one from another. A 22
9 ALLELOPATHIC TENDENCIES OF IMPATIENS GLANDURIFERA LEAF EXTRACTS laboratory bioassay can only give evidence that allelopathy is an explanation for the phenomenon observed. However, it is important to also consider other possibilities on the phenomenon. For example, it is difficult to separate the effect allelopathy has on the plant from other, common effects such as sunlight, nutrients and water (Qasem, 2001). The invasive nature of I. glandulifera can be due to its height: it can shade all other plants from the sunlight and use its powerful seed ejaculation method to disperse hundreds of seeds. It could also be possible that the allelopathic affect of Himalayan balsam is not the direct result of the toxic chemicals but due to the toxins causing the plant to be susceptible to other harms (for example invasions of pathogens) (Chou, 1999). The chemicals can alter different things, causing seeds to be unable to germinate: allelochemicals can affect the plant indirectly by altering soil/ population and activity of microorganisms or directly by changing the mineral uptake, protein synthesis, respiration, genetic material or enzyme activity (Rizvi, 1992). The effect of allelochemicals on germination, as shown in this experiment, is only a symptom: a secondary sign of a primary change (Winter, 1961). There must be some sort of metabolic change (primary change) before the inhibition of germination (secondary change) is observed. This experiment did not focus on the primary change. It only showed that there is a secondary change: ANOVA and t- tests showed that the results were significantly different from each other (P=1.11 x 10-16, thus H o rejected and p = x 10-8 this H o rejected) and so there was a difference between the germination of the seeds in different concentrations of I. glandulifera extracts. These results, though being supported by a few literature references, are preliminary and need further studies to eliminate other possibilities of the phenomenon observed (such as competition). As stated in the introduction to this investigation, in Finland it is common practice to cut the stems of I. glandulifera before the plant has reached maturity. This is believed to help prevent the spreading of this invasive alien species, as the plants are not able to scatter their seeds. However, the results of this investigation show that the leaves of I. glandulifera have an inhibitory effect on T. repen seeds. Therefore it can be concluded that there is a possibility that when I. glandulifera is cut and left on the ground, the leaves may decompose and release some of these chemicals into the soil that can cause the inhibition of germination and growth of seeds. Consequently, though cutting may help with the spreading of the species, it may also prevent the germination and growth of new species in the area. A better way of ridding the land of this invasive alien species is to pull the plant from the ground and dispose of it: by letting it decompose there is a chance of releasing toxic allelochemicals into the soil that could potentially harm other species. 23
10 MONONEN References Anaya, A., Allelopathy as a tool in the management of biotic resources in agroecosystems. Critical Reviews in Plant Sciences, 18, Beerling, D. J., The impact of temperature on the northern distribution limits of the introduced species Fallopia japonica and Impatiens glandulifera in northwest Europe. Journal of Biogeography, 20, Bell, D. T., The influence of osmotic pressure in tests for allelopathy. Illinois State Academy of Science. Transactions A publication, 67, Chou, C. H., Role of allelopathy in plant biodiversity and sustainable agriculture. Critical Reviews in Plant Sciences, 18, Finnish Meteorological Institute, June was cool and wet. Press Release Archive. Hannaway, D. B., and Cool, M., White Clover (Trifolium repens L.). &use=soil Helmisaari, H., NOBANIS Invasive Alien Species Fact Sheet: Impatiens glandulifera. Online Database of the European Network on Invasive Alien Species, Kollmann, J., and Bañuelos, M. J., Latitudinal trends in growth and phenology of the invasive alien plant Impatiens glandulifera (Balsaminaceae). Diversity and Distrubutions, 10, Kruse, M., Strandberg, M., and Strangberg, B., Ecological effects of allelopathic plants: A review. Department of Terrestrial Ecology, Silkeborg Denmark, NERI Technical Report, No. 315 Lampinen, R., and Lahti, T., Kasviatlas Helsinki: Helsinki University, Finnish University of Natural History. Mallik, M. A. B., and Williams, R. D., Allelopathic principles for sustainable agriculture. Allelopathy Journal, 24, 1 34 Marambe, B., Potential of allelopathy for weed management in wet - seeded rice cultivation in Sri Lanka. In M. Olofsdotter (Ed.). Allelopathy in Rice, (pp ). Philippines: IRRI (International Rice Research Institute) Narwal, S., (2010) Allelopathy in ecological sustainable organic agriculture. Allelopathy Journal, 25, Qasem, J.R., and Foy, C.L., Weed allelopathy, its ecological impacts and future prospects: a review. In R. K. Kohli, P. S. Harminder, and D. R. Batish (Eds.) Allelopathy in Agroecosystems, (pp ). New York, NY: Food Products Press. Reigosa, M.J., Roger, L.J., Pedrol, N., and González L., Allelopathy: A Physiological Process with Ecological Implications. Dordrecht: Springer. Rice, E.L., Allelopathy. Orlando, FL: Academic. Rizvi, S. J. H., and Rizvi, V., Allelopathy: Basic and Applied Aspects. London: Chapman and Hall. Shahrokhi, S., Kheradmand, B., Mehrpouyan, M., Farboodi, M., and Akbarzadeh, M., Effect of different concentrations of aqueous extract of bindweed, Convolvulus arvensis on initial growth of Abidar barley (Hordeum vulgare) cultivar in greenhouse. International Proceedings of Chemical, Biological and Environmental Engineering, 24, Vrchotová, N., Šerá, B., and Krejčová, J., Allelopathic activity of extracts from Impatiens species. Plant Soil Environment, 57,
11 ALLELOPATHIC TENDENCIES OF IMPATIENS GLANDURIFERA LEAF EXTRACTS Williams, W.M., (1987) Adaptive variation. In M. J. Baker and W. M. Williams (Eds.), White Clover, (pp ). Wallingford: CAB International. Willis, S.G., Hulme, P.E., (2004) Environmental severity and variation in the reproductive traits of Impatiens glandulifera. Functional Ecology, 18, Winter, A. G., New physiological and biological aspects in the interrelation between higher plants. Society of Experimental Biology Symposium, 15,
BIOLOGY. Word count: IB Exam May 2017
The allelopathic effect of extracts of Vaccinium myrtillus, Empetrum nigrum and Sphagnum girgensohnii on the germination and growth of Lepidium satvium IB Exam May 2017 BIOLOGY Word count: 3814 ABSTRACT
More informationROLE OF THE ALLELOPATHY IN MIXED VEGETABLE CROPS IN THE ORGANIC FARMING
Abstract Scientific Papers. Series A. Agronomy, Vol. LVI, 2013 ISSN 2285-5785; ISSN CD-ROM 2285-5793; ISSN Online 2285-5807; ISSN-L 2285-5785 ROLE OF THE ALLELOPATHY IN MIXED VEGETABLE CROPS IN THE ORGANIC
More informationBy the end of this lesson, you should be able to
Allelopathy 1 Allelopathy By the end of this lesson, you should be able to define allelopathy explain the difference between allelopathy and competition identify the key interactions in allelopathy provide
More informationALLELOPATHY: NATURAL AND AN ENVIRONMENT-FRIENDLY UNIQUE TOOL FOR WEED CONTROL
ALLELOPATHY: NATURAL AND AN ENVIRONMENT-FRIENDLY UNIQUE TOOL Arpana Mishra* FOR WEED CONTROL Abstract: Allelopathy term refers to all biochemical interactions ( stimulatory and inhibitory) among plants,
More informationSome changes in germination and morphological traits of black seed under different soil types and common bean densities
Journal of Biodiversity and Environmental Sciences (JBES) ISSN: 2220-6663 (Print) 2222-3045 (Online) Vol. 3, No. 5, p. 31-35, 2013 http://www.innspub.net RESEARCH PAPER OPEN ACCESS Some changes in germination
More informationThe allelopathic effects of juglone containing nuts Abstract Allelopathy is the inhibition of the growth of
The allelopathic effects of juglone containing nuts Catherine Qin, Manavi Nagai, Whitney Hagins, and Reginald Hobbs* Department of Science AP Biology Lexington High School, 251 Waltham Street, Lexington,
More informationPreliminary phytoconstituents screening of some weeds and their potential toxicity on rice variety- Tarom via decomposition bioassay
2011 International Conference on Environmental, Biomedical and Biotechnology IPCBEE vol.16 (2011) (2011)IACSIT Press, Singapoore Preliminary phytoconstituents screening of some weeds and their potential
More informationAbiotic Stress in Crop Plants
1 Abiotic Stress in Crop Plants Mirza Hasanuzzaman, PhD Professor Department of Agronomy Sher-e-Bangla Agricultural University E-mail: mhzsauag@yahoo.com Stress Stress is usually defined as an external
More informationThe effect of temperature on the germination of Arabidopsis thaliana seeds
The effect of temperature on the germination of Arabidopsis thaliana seeds Tina Afshar, Nikeisha Dass, Caron Lau, Alana Lee Abstract Arabidopsis thaliana is a model organism widely used by researchers
More informationAILANTHUS ALTISSIMA SPECIES INVASION ON BIODIVERSITY CAUSED BY POTENTIAL ALLELOPATHY
AILANTHUS ALTISSIMA SPECIES INVASION ON BIODIVERSITY CAUSED BY POTENTIAL ALLELOPATHY C. BOSTAN, F. BORLEA, Corina MIHOC, Mihaela SELESAN Banat s University of Agricultural Sciences and Veterinary Medicine
More informationAssessment Schedule 2016 Biology: Demonstrate understanding of biological ideas relating to micro-organisms (90927)
NCEA Level 1 Biology (90927) 2016 page 1 of 5 Assessment Schedule 2016 Biology: Demonstrate understanding of biological ideas relating to micro-organisms (90927) Evidence Statement Question One No response
More informationName: B5 PLANT HORMONES. Class: Practice questions. Date: 53 minutes. Time: 53 marks. Marks: Biology Only. Comments: Page 1 of 25
B5 PLANT HORMONES Practice questions Name: Class: Date: Time: 53 minutes Marks: 53 marks Comments: Biology Only Page of 25 Hormones called auxins control plant growth. A student investigated plant growth
More informationAssessment Schedule 2017 Biology: Demonstrate understanding of biological ideas relating to the life cycle of flowering plants (90928)
NCEA Level 1 Biology (90928) 2017 page 1 of 5 Assessment Schedule 2017 Biology: Demonstrate understanding of biological ideas relating to the life cycle of flowering plants (90928) Evidence Statement QUESTION
More informationALLELOPATHIC EFFECTS OF FIVE SELECTED WEED SPECIES ON SEED GERMINATION AND SEEDLING GROWTH OF CORN
J.Soil.Nature. 2 (2):13-18 (July 2008) ALLELOPATHIC EFFECTS OF FIVE SELECTED WEED SPECIES ON SEED GERMINATION AND SEEDLING GROWTH OF CORN M. A. SAMAD, M. M. RAHMAN 1, A. K. M. M. HOSSAIN 1, M. S. RAHMAN
More informationStudy of Allelopathic Interactions of weeds on of Wheat (Triticum aestivum L.) and Moong (Vigna radiata) using Equal-Compartment-Agar Method (ECAM)
International Journal of Applied Agricultural Research ISSN 0973-2683 Volume 12, Number 2 (2017) pp. 247-254 Research India Publications http://www.ripublication.com Study of Allelopathic Interactions
More informationThe Effect of Phosphorus Concentration on the Intrinsic Rate of Increase. for Salvinia minima. Aaron Jacobs
The Effect of Phosphorus Concentration on the Intrinsic Rate of Increase for Salvinia minima Aaron Jacobs Partners: Andrew Watts Derek Richards Jen Thaete Introduction: Salvinia minima is an aquatic fern,
More information25-3 Plant Adaptations Slide 2 of 29
2 of 29 Aquatic Plants How are plants adapted to different environments? 3 of 29 Aquatic Plants Aquatic Plants To take in sufficient oxygen, many aquatic plants have tissues with large air-filled spaces
More informationRequirements for Prospective Teachers General Science. 4.1a Explain energy flow and nutrient cycling through ecosystems (e.g., food chain, food web)
Ecology and Conservation Biology (Biol 116) - Syllabus Addendum for Prospective Teachers Ricklefs, R. E., (2001). The Economy of Nature, 5 th Edition. W.H. Freeman & Co Chapter Ch 6-Energy in the Ecosystem
More informationRESEARCH ARTICLE INTRODUCTION
J.Natn.Sci.Foundation Sri Lanka 2015 43 (1): 57-64 DOI: http://dx.doi.org/10.4038/jnsfsr.v43i1.7915 RESEARCH ARTICLE Effect of incorporating the residues of Sri Lankan improved rice (Oryza sativa L.) varieties
More informationEffect of Allelopathic weeds on Characteristics seed Growth in maize (Zea mays L. cv. KSC 704)
Advances in Environmental Biology, 6(1): 297-301, 2012 ISSN 1995-0756 297 This is a refereed journal and all articles are professionally screened and reviewed ORIGINAL ARTICLE Effect of Allelopathic weeds
More informationY8 Science Controlled Assessment Topics & Keywords
Y8 Science Controlled Assessment Topics & Biology Respiration. Know that respiration in living organisms can be aerobic or anaerobic The word equation for aerobic respiration The process of anaerobic respiration
More informationAllelopathy In Trees
Allelopathy In Trees by Dr. Kim D Coder, Daniel B. Warnell School of Forest Resources, University of Georgia 4/99 Trees have developed in ecological systems filled with many other organisms. The environment,
More informationInt.J.Curr.Res.Aca.Rev.2016; 4(6): 16-21
Allelopathic Effects of (Sorghum bicolor L.) Extracts on Germination and Seeding Growth of (Triticum aestivum L.). M.S. AL- Juboory* and Walla M. AL- Juboory Department of Biology, College of Science,
More informationUNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS International General Certificate of Secondary Education
UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS International General Certificate of Secondary Education *7021514936* BIOLOGY 0610/02 Paper 2 Core May/June 2007 1 hour 15 minutes Candidates answer on
More informationFINAL VERSION_ Secondary Preservice Teacher Standards -- Life Science AFK12SE/NGSS Strand Disciplinary Core Idea
Secondary Preservice Teacher Standards -- Life Science AFK12SE/NGSS Strand Disciplinary Core Idea LS1: From Molecules to Organisms: Structures and Processes LS1.A: Structure and Function How do the structures
More informationcan affect division, elongation, & differentiation of cells to another region of plant where they have an effect
Note that the following is a rudimentary outline of the class lecture; it does not contain everything discussed in class. Plant Hormones Plant Hormones compounds regulators growth or can affect division,
More informationCompetition Among Organisms
A Vote for Ecology Activity 5 Competition Among Organisms GOALS In this activity you will: Observe the effects of competition among plants for space and nutrients. Describe the possible effects of introducing
More informationOntario Science Curriculum Grade 9 Academic
Grade 9 Academic Use this title as a reference tool. SCIENCE Reproduction describe cell division, including mitosis, as part of the cell cycle, including the roles of the nucleus, cell membrane, and organelles
More informationWeed Suppression by Buckwheat
98 Weed Suppression by Buckwheat Current Advances in Buckwheat Research (1995) : 693-697 Tohru Tominaga and Takako Uezu Faculty of Agriculture, Shinshu University, Ina, Nagano, Japan Abstract To clarify
More informationNAME ONE THING we have in common with plants. If
Cellular Respiration NAME ONE THING we have in common with plants. If you said cellular respiration, you are right. That is one thing we have in common with plants, slugs, slime mold, and spiders. Living
More informationCHAPTER 52 Study Questions (An Introduction to Ecology and the Biosphere)
WLHS / AP Bio / Monson Name CHAPTER 52 Study Questions (An Introduction to Ecology and the Biosphere) 52.1: Earth s climate varies by latitude and season and is changing rapidly (p. 1144-1150) 1) Distinguish
More informationA Level. A Level Biology. AQA, OCR, Edexcel. Photosynthesis, Respiration Succession and Nutrient Cycle Questions. Name: Total Marks: Page 1
AQA, OCR, Edexcel A Level A Level Biology Photosynthesis, Respiration Succession and Nutrient Cycle Questions Name: Total Marks: Page 1 Q1. The diagram shows the energy flow through a freshwater ecosystem.
More informationPlant Growth and Development
1. Define plasticity. Give an example? A: Plant Growth and Development The ability of the plants to follow different pathways in response to the environment or phases of life to form different kinds of
More information1 (a) carbon dioxide / CO 2 ; (aerobic) respiration ; (simple) diffusion ; [3] A excretion I gas exchange
1 (a) carbon dioxide / CO 2 ; (aerobic) respiration ; (simple) diffusion ; [] A excretion I gas exchange (b) water enters by osmosis ; down a water potential gradient / high(er) to low(er) water potential
More informationBiogeographic Processes
Biogeographic Processes Energy and Matter Flow in Ecosystems Ecological Biogeography Ecological Succession Historical Biogeography Biogeographic Processes Biogeography examines the distribution of plants
More informationDesert Patterns. Plants Growth and reproduction Water loss prevention Defenses. Animals Growth and reproduction Water loss prevention Defenses
Desert Patterns Plants Growth and reproduction Water loss prevention Defenses Animals Growth and reproduction Water loss prevention Defenses Abiotic Features Introduction A major emphasis in ecology is
More informationGrade 4 Structures of Life Unit Template
Delaware Science Coalition Grade 4 Structures of Life Unit Template Copyright 2008 Delaware Department of Education Copyright 2008 Delaware Department of Education Page 1 of 13 Preface: This unit has been
More informationChapter 8. Biogeographic Processes. Upon completion of this chapter the student will be able to:
Chapter 8 Biogeographic Processes Chapter Objectives Upon completion of this chapter the student will be able to: 1. Define the terms ecosystem, habitat, ecological niche, and community. 2. Outline how
More informationTUNDRA. Column 1 biome name Column 2 biome description Column 3 examples of plant adaptations
Biome Cards (pp. 1 of 7) Cut out each biome card and divide each card into three sections. Place all sections in a plastic storage bag. Have one bag for every two students. Column 1 biome name Column 2
More information5. Which graph represents a population that grew and is maintained at the carrying capacity of its ecosystem?
Date: Pd. Regents Review Assignment #5 Living Environment 2 Part A Questions 1. Which structures carry out life functions within cells? (1) tissues (3) organelles (2) organ systems (4) organs 2. The sorting
More informationBiology and management of dodder a new threat to the canola industry
Biology and management of dodder a new threat to the canola industry Abul Hashem Department of Agriculture and Food Western Australia Centre for Cropping Systems P.O. Box 483, Northam WA 641, Australia
More informationPhotosynthesis limiting factors
Photosynthesis limiting factors What you should know by the end of this unit: Photosynthesis is the process by which green plants make their own food. Light energy is trapped by the green pigment chlorophyll.
More informationWeed Identification and Control. Jim Wanstall NMDA State Noxious Weed Coordinator
Weed Identification and Control Jim Wanstall NMDA State Noxious Weed Coordinator What Is A Weed? A weed is any plant that interferes with the management objectives for a particular site. An invasive weed
More informationFlowers Seeds Pollination Germination
* Flowers Seeds Pollination Germination *In order for plants to be successful in many different environments they must be able to reproduce themselves. *The reproductive patterns of plants reflect the
More informationWeather Report 04 April 2018
Weather Report 04 April 2018 South Africa - Weather Alternating periods of rain and sunshine will evolve across South Africa during the coming week. Moisture totals through next Tuesday morning will range
More informationAllelopathic effects of Datura stramonium on seed germination and seedling vigour of Triticum aestivum (variety GW 273).
Allelopathic effects of Datura stramonium on seed germination and seedling vigour of riticum aestivum (variety GW 273). Waseem Ahmad, Aparna Alia¹, Fatima Khan². Department of Botany, Rajeev Gandhi College
More information1 The Cycles of Matter
CHAPTER 19 1 The Cycles of Matter SECTION Cycles in Nature BEFORE YOU READ After you read this section, you should be able to answer these questions: Why does matter need to be recycled? How are water,
More informationInvolving Your Students in Cutting-Edge Biological Research
351 Involving Your Students in Cutting-Edge Biological Research Kathy Frame National Association of Biology Teachers 11250 Roger Bacon Drive #19 Reston, VA 20190-5202 (703) 471-1134, kframe@capaccess.org
More informationPhotosynthesis Revision 1
Photosynthesis Revision 73 minutes 73 marks Page of 35 Q. This question is about photosynthesis. (a) Plants make glucose during photosynthesis. Some of the glucose is changed into insoluble starch. What
More information2018 Version. Photosynthesis Junior Science
2018 Version Photosynthesis Junior Science 1 Plants fill the role of Producers in a community Plants are special because they have leaves and are able to produce their own food by the process of photosynthesis
More informationCorey V. Ransom, Charles A. Rice, and Joey K. Ishida Malheur Experiment Station Oregon State University Ontario, OR, 2004.
FACTORS INFLUENCING VAPAM EFFICACY ON YELLOW NUTSEDGE TUBERS Corey V. Ransom, Charles A. Rice, and Joey K. Ishida Malheur Experiment Station Oregon State University Ontario, OR, 2004 Introduction Yellow
More informationLab 4 The Scientific Method and Allelopathy
Lab 4 The Scientific Method and Allelopathy I. Central questions How does the scientific method work? How do plants affect each other? II. Learning Objectives At the end of this lab you will be able to
More information8 Reproduction in flowering plants
Self-assessment questions 8.01 8 Reproduction in flowering plants 1 Which is the most accurate statement? The principal role of a flower in the life cycle of a plant is: (a) attracting insects (b) producing
More informationTAKE A LOOK 3. Complete Carbon dioxide in the air is used for. The Cycles of Matter continued
CHAPTER 2 1 The Cycles of Matter SECTION Cycles in Nature BEFORE YOU READ After you read this section, you should be able to answer these questions: Why does matter need to be recycled? How are water,
More informationBiology End-Of-Course Braille Practice Test Answer Key
Question 1 Reporting Category: Scientific Process Benchmark: SC.BS.1.3 Defend and support conclusions, explanations, and arguments based on logic, scientific knowledge, and evidence from data Answer Key:
More informationWeeds, Exotics or Invasives?
Invasive Species Geography 444 Adopted from Dr. Deborah Kennard Weeds, Exotics or Invasives? What is a weed? Invasive species? 1 Weeds, Exotics or Invasives? Exotic or non-native: Non-native invasive pest
More information9/10/ What Shapes an Ecosystem? Biotic and Abiotic Factors
9/10/14 4-2 What Shapes an Ecosystem? Biology 1 of 39 Ecosystems are influenced by a combination of biological and physical factors. The biological influences on organisms within an ecosystem are called
More informationInspired by nature. Callisto is currently under review by the Pest Management Regulatory Agency and not yet registered for use in Canada.
H E R B I C I D E Inspired by nature Callisto is currently under review by the Pest Management Regulatory Agency and not yet registered for use in Canada. H E R B I C I D E Inspired by nature Callisto
More information1 29 g, 18% Potato chips 32 g, 23% 2 30 g, 18% Sugar cookies 35 g, 30% 3 28 g, 19% Mouse food 27 g, 18%
1. When testing the benefits of a new fertilizer on the growth of tomato plants, the control group should include which of the following? A Tomato plants grown in soil with no fertilizer B Tomato plants
More informationCells: 3 Star. Which row in the chart below best explains the movement of some molecules between the model cell and the solution in the beaker?
ells: 3 Star 1. ase your answer(s) to the following question(s) on the diagram below and on your knowledge of biology. The diagram represents a model cell setup. The locations of three different substances
More informationEffect of Parthenium hysterophorus L. on Germination and Elongation of Onion (Allium cepa) and Bean (Phaseolus vulgaris)
Research Journal of Chemical and Environmental Sciences Volume 1 Issue 2 (June 2013): 17-21 Available Online http://www.aelsindia.com/rjces.htm 2013 AELS, India Online ISSN 2321-1040 ORIGINAL ARTICLE Effect
More information7 th Grade GLEs (Draft Alignment 4/22/08) EARL 1 Systems
7 th Grade GLEs (Draft Alignment 4/22/08) EARL 1 Systems Diversity of Life (DL) Characteristics of Living Matter 1.1.6 Understand how to classify organisms by their external and internal structures. W
More informationTREES. Functions, structure, physiology
TREES Functions, structure, physiology Trees in Agroecosystems - 1 Microclimate effects lower soil temperature alter soil moisture reduce temperature fluctuations Maintain or increase soil fertility biological
More informationThe Green Machine curriculum addresses the following California Science Content Standards: KINDERGARTEN
The Green Machine curriculum addresses the following California Science Content Standards: KINDERGARTEN PHYSICAL SCIENCES 1. Properties of materials can be observed, measured and predicted. a. Objects
More informationChapter 52 An Introduction to Ecology and the Biosphere
Chapter 52 An Introduction to Ecology and the Biosphere Ecology The study of the interactions between organisms and their environment. Ecology Integrates all areas of biological research and informs environmental
More informationChapter 4 AND 5 Practice
Name: Chapter 4 AND 5 Practice 1. Events that occur in four different ecosystems are shown in the chart below. Which ecosystem would most likely require the most time for ecological succession to restore
More informationMichigan Curriculum Framework
Elementary Reference Content Standards Wetlands (with teacher Rainforest (with teacher 1. All students will apply an understanding of cells to the functioning of multicellular organisms; and explain how
More informationInvasive Species Management Plans for Florida
Invasive Species Management Plans for Florida Air Potato Dioscorea bulbifera (L.) Dioscoreaceae INTRODUCTION A native to tropical Asia, air potato, Dioscorea bulbifera, was first introduced to the Americas
More informationNeeds of Seeds. Teacher Notes. Purpose. Related Concepts. Explanation
Needs of Seeds Teacher Notes Purpose The purpose of this assessment probe is to elicit students ideas about seeds. It specifically probes to find out if students recognize that a seed has needs, similar
More information1. The graph below represents a change in event A that leads to changes in events B and C.
1. The graph below represents a change in event A that leads to changes in events B and C. Which row in the chart best identifies each event in the graph? A) 1 B) 2 C) 3 D) 4 2. A stable ecosystem is characterized
More informationHerbivory: the consumption of plant parts (generally leaves and roots) by animals
Herbivory: the consumption of plant parts (generally leaves and roots) by animals >25% of all species on earth are herbivores >50% of all organisms are plant and herbivores, so their interactions have
More informationECOSYSTEMS AND THEIR LIVING COMMUNITIES
ECOSYSTEMS AND THEIR LIVING COMMUNITIES COMMUNITY Each community is made up of populations of various organisms living in the same location at the same time. community 1 = popln 1 + popln 2 + popln 3 Each
More informationWhy do Invasive Species Successfully Establish & Invade?
Why do Invasive Species Successfully Establish & Invade? Many are introduced, few become invasive Hypotheses about why invaders succeed: 1. Invasive species have traits that favor establishment and spread
More informationScholarship 2008 Biology
93101Q S 931012 Scholarship 2008 Biology 9.30 am Saturday 22 November 2008 Time allowed: Three hours Total marks: 24 QUESTION booklet There are THREE questions in this booklet. Answer ALL questions. Write
More informationGeorgia Performance Standards for Urban Watch Restoration Field Trips
Georgia Performance Standards for Field Trips 6 th grade S6E3. Students will recognize the significant role of water in earth processes. a. Explain that a large portion of the Earth s surface is water,
More informationTUNKHANNOCK AREA SCHOOL DISTRICT SCIENCE CURRIULUM GRADE 2
TUNKHANNOCK AREA SCHOOL DISTRICT SCIENCE CURRIULUM GRADE 2 Chapter 4 (How Living Things Grow and Change) 3.1.2.C.2. Explain that living things can only survive if their needs are being met. 3.1.2.A.3.
More informationBiomes Section 2. Chapter 6: Biomes Section 2: Forest Biomes DAY ONE
Chapter 6: Biomes Section 2: Forest Biomes DAY ONE Of all the biomes in the world, forest biomes are the most widespread and the most diverse. The large trees of forests need a lot of water, so forests
More informationMrs. Fanek Ecology Date
Name Period Mrs. Fanek Ecology Date 1. The graph below represents a change in event A that leads to changes in events B and C. Which row in the chart best identifies each event in the graph? A) 1 B) 2
More informationEcology: The science concerned with the relationships among living things and their environment.
ECOSYSTEM VOCABULARY IN PACKET Ecology: The science concerned with the relationships among living things and their environment. Ecosystem: A community that includes all the living and nonliving things
More informationEnzyme Catalysis Lab
AP Biology Name: Enzyme Catalysis Lab Objectives In this laboratory, you will observe the role of an enzyme (catalase) in conversion of hydrogen peroxide (H 2 O 2 ) to water and oxygen determine the rate
More informationStockton Unified School District Instructional Guide for BIOLOGY NGSS Pilot for both 4X4 and Traditional. 1st Quarter
1st Quarter Unit NGSS Standards Required Labs Supporting Text Content Academic Suggested Labs and Activities Biochemistry HS-LS-1-6 Ch. 1 & 2 molecules elements amino acids Carbon-based Carbon Hydrogen
More informationPlant Structure and Organization - 1
Plant Structure and Organization - 1 In our first unit of Biology 203 we will focus on the structure and function of the higher plants, in particular the angiosperms, or flowering plants. We will look
More informationPage 1 of 5. New: evidence, measure, nutrients, light, soil, transport, volume, water, warmth, insect, pollen, pollinate, nectar.
National Curriculum Objectives: (Statutory requirements) a) Identify and describe the functions of different parts of flowering : roots, stem/trunk, leaves and flowers b) Explore the requirements of for
More informationUnit D: Controlling Pests and Diseases in the Orchard. Lesson 5: Identify and Control Diseases in the Orchard
Unit D: Controlling Pests and Diseases in the Orchard Lesson 5: Identify and Control Diseases in the Orchard 1 Terms Abiotic disease Bacteria Biotic diseases Cultural disease control Disease avoidance
More informationWHEN CAN YOU SEED FALLOW GROUND IN THE FALL? AN HISTORICAL PERSPECTIVE ON FALL RAIN
WHEN CAN YOU SEED FALLOW GROUND IN THE FALL? AN HISTORICAL PERSPECTIVE ON FALL RAIN Steve Petrie and Karl Rhinhart Abstract Seeding at the optimum time is one key to producing the greatest yield of any
More informationBIO 2 GO! Abiotic Factors 3.2.2
BIO 2 GO! Abiotic Factors 3.2.2 Abiotic factors are non-living, but are extremely important to all cells as well as the entire organism. Cells live within a narrow range of abiotic factors. Beyond that
More information*Modifications in reproduction were key adaptations enabling plants to spread into a variety of terrestrial habitats.
Plant Reproduction *Modifications in reproduction were key adaptations enabling plants to spread into a variety of terrestrial habitats. Reproduction In Plants Plant reproduction is the production of new
More informationName: Characteristics of Life and Ecology Guided Notes (PAP)
Name: Characteristics of Life and Ecology Guided Notes (PAP) I. What is Biology? a. Biology is the study of II. The Eight Characteristics of Life a. Organization & the presence of or more cells b. Response
More informationAugustin Pyramus De Candolle, a botanist and naturalist, in 1832, suggested that soil sickness was caused by chemicals released by the crop.
Allelopathy Chapter 1: Introduction History Theophrastus (ca. 300 B.C.E.), a student and successor to Aristotle, wrote about allelopathic reactions in his botanical works. He has been called the "father
More informationHALF YEARLY EXAMINATIONS
Secondary School HALF YEARLY EXAMINATIONS 2016-2017 FORM: 3 Biology Time: 2 hours Name: Class: Section A: Answer ALL questions in the space provided. This section carries a total of 55 marks. 1. The frog
More informationLecture 8 Insect ecology and balance of life
Lecture 8 Insect ecology and balance of life Ecology: The term ecology is derived from the Greek term oikos meaning house combined with logy meaning the science of or the study of. Thus literally ecology
More informationFundamental Plant Processes - Plant Parts & Functions
Fundamental Plant Processes - Plant Parts & Functions irections: nswer the following questions. 1. Which of the following plant parts supports the stem?. Roots B. tem C. Leaves. Flowers 2. Which structure
More informationC1 Weeds in North Queensland
C1 Weeds in North Queensland Introduction This presentation covered Siam weed (Chromolaena odorata), the Four Tropical Weeds (Miconia spp., Mikania macrantha, Clidemia hirta, Limnocharis flava), and Mimosa
More information4-2 What Shapes an Ecosystem?
Biology 1 of 39 4-2 What Shapes an Ecosystem? 2 of 39 Biotic and Abiotic Factors Biotic and Abiotic Factors Ecosystems are influenced by a combination of biological and physical factors. 3 of 39 1 Biotic
More informationPlant Development. Chapter 31 Part 1
Plant Development Chapter 31 Part 1 Impacts, Issues Foolish Seedlings, Gorgeous Grapes Gibberellin and other plant hormones control the growth and development of plants environmental cues influence hormone
More informationWeed Competition and Interference
Weed Competition and Interference Definition two organisms need essential materials for growth and the one best suited for the environment will succeed (humans usually manipulate so that crops succeed)
More informationAssessment Schedule 2013 Biology: Demonstrate understanding of the responses of plants and animals to their external environment (91603)
NCEA Level 3 Biology (91603) 2013 page 1 of 6 Assessment Schedule 2013 Biology: Demonstrate understanding of the responses of plants and animals to their external environment (91603) Assessment Criteria
More informationPlant responses to climate change in the Negev
Ben-Gurion University of the Negev Plant responses to climate change in the Negev 300 200 150? Dr. Bertrand Boeken Dry Rangeland Ecology and Management Lab The Wyler Dept. of Dryland Agriculture Jacob
More informationB L U E V A L L E Y D I S T R I C T C U R R I C U L U M Science 7 th grade
B L U E V A L L E Y D I S T R I C T C U R R I C U L U M Science 7 th grade ORGANIZING THEME/TOPIC UNIT 1: CELLS Structure and Function of Cells MS-LS1-1. Conduct an investigation to provide evidence that
More information2. The development of revolutionized the of life.
Science 10 Unit 7 Worksheet Chapter 15, Part 1. 1. Briefly describe the three main parts of cell theory: 2. The development of revolutionized the of life. 3. Individual cells need to take in to build and
More information