Horticulture 201H Spring, 2002 Exam 2 Name:

Transcription

1 Horticulture 201H Spring, 2002 Exam 2 Name: Section 1. In the space to the left of the statements below, write the word(s) that best fit the definition or description. (20 pts) Vegetative reproduction structure of the gladiolus which is a vertically flattened stem. Vegetative reproduction structure that consists mostly of swollen leaf bases. Swollen underground stem that grows horizontally producing an upright leafy shoot at its tip (an example would be the iris). Tissue responsible for healing of the graft union. Type of root that develops on cuttings placed in a mist bed. Name given to plant that is composed of more than one genotype growing adjacent; variegated foliage and thornless stems are examples. Category of hormones believed to be responsible for phototropic responses. Plant growth regulator commonly used to stimulate rooting of woody cuttings Type of propagation in which roots are developed on an intact stem buried with soil. Proliferation of undifferentiated cells occuring during the first stage of graft healing. Type of graft in which the scion is reduced to a single vegetative bud. Name given to the graft partner which becomes the root system of the plant. Term that describes the failure of a graft union for physiological reasons rather than problems with poor grafting technique. Photoperiod response associated with fall blooming plants such as chrysanthemum. Name of color commonly associated with 660 nm wavelength light. Photoperiod response generally associated with plants growing in the tropics. Name given to the pigment/protein complex assumed to be the "biological clock." The hormone commonly associated with fruit ripening. Suppression of the growth of lateral buds by an actively growing shoot tip. Type of growth regulator commonly used to stimulate shoot development in vitro.

2 Section 2. Matching. Write the letter of the term that best describes or matches the statements or phrases below. (20 pts) Terms a. auxin g. NAA m. corm b. cytokinin h. phytochrome n. tuberous root c. ABA i. cutting o. runner d. gibberellin j. layering p. tuber e. ethylene k. grafting q. bulb f. zeatin l. clone r. rhizome Hormones/growth regulators hormone believed responsible for rapid elongation of flower after chilling treatment hormone implicated in stomatal closure hormone that is transported basipetally suppressing growth of axillary buds treatment of cucumbers with this hormone can alter the sex expression of flowers gravitropism is believed to be due to lateral concentration gradient of this hormone "gassing" bananas to cause them to ripen causes this hormone to increase in tissue tomato cotyledons treated with this growth regulator produce roots in tissue culture 2 Vegetative structures (general) subterranean swollen stem that terminates a stolon subterranean storage structure that contains no preformed vegetative buds group of plants propagated from a common ancestor by vegetative means piece of a stem or root used to start a new plant inducing roots to form on stem prior to its removal from parent plant formation of compound genetic system by mechanically forcing two stems to grow together Vegetative structures (specific); name the type of structure associated with the following plants: onion Irish potato sweet potato orchid garlic Easter lily tulip

3 3 Section 3. Plant Nutrition. Answer the following questions about fertilizers and plant nutrients. (20 pts) List 4 nutrients which have deficiency symptoms characterized as general "yellowing" or chlorosis of the leaves. For each, name a fertilizer or soil amendment that is commonly applied to overcome that deficiency. (Note: application of the element itself is not a satisfactory answer, since application of elemental nutrients is generally prohibitively expensive) Rank the following elements in order of their relative composition in the dry matter of a plant (higher concentration on the left): Molybdenum, carbon, phosphorus, nitrogen, iron > > > > Compare and contrast "organic" and "inorganic" sources of plant nutrients. Discuss factors such as availability, cost, ease of handling, and benefits to plant health.

4 4 Section 4. "Keeps on Ticking." The following questions are meant to test your understanding of the biological clock in plants. Your answers will be evaluated for accuracy and completeness, but don't confuse that with length! (20 pts total) Using labeled diagrams and brief sentences, describe how the "biological clock" functions. (10 pts) List 3 different physiological functions of plants that are regulated by the same system that regulates the biological clock. (5 pts) Describe how the mechanism of the "biological clock" can also be considered a "biological calendar." (5 pts)

5 Section 5. Definitions. Define the following terms as they were used in the context of this course. (20 pts total) 5 vernal equinox protoplast protoplast fusion somatic embryo organogenesis micropropagation medium somaclonal variation explant intermittent mist