GENETIC DIVERGENCE STUDIES IN CHRYSANTHEMUM (DENDRANTHEMA GRANDIFLORA TZVELEV)

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1 GENETIC DIVERGENCE STUDIES IN CHRYSANTHEMUM (DENDRANTHEMA GRANDIFLORA TZVELEV) * P. Lalitha Kameswari 1, M. Pratap 1, G. Anuradha 2 and Hameedunnisa Begum 1 1 Floricultural Research Station, Dr. YSR Horticultural University, Rajendranagar, Hyderabad, (A.P.), India 2 Institute of Biotechnology, ANGRAU, Rajendranagar, Hyderabad, (A.P.), India *Author for Correspondence ABSTRACT In chrysanthemum based on Mahalanobis s D 2 analysis, genetic divergence studies were conducted in one hundred and four genotypes and they were grouped into eleven divergent clusters. The highest inter cluster D 2 value was recorded between clusters VI and IX (195.87) indicating that crosses may be attempted between the genotypes of cluster VI (Apurva Singar and Local Button) and cluster IX (Miss India, Tambra, White Silver Cloud, Red Queen and Swan) to obtain new desirable recombinants in chrysanthemum. Among all the characters, the most important character contributing to divergence was number of ray florets per head followed by number of disc florets per head and flower yield per plant. With principal component analysis, the first eight principal components with eigen values more than one contributed to per cent of cumulative variability. Key Words: Chrysanthemum, D 2 Analysis, Germplasm and Genetic Divergence INTRODUCTION Chrysanthemum is one of the oldest cultivated flower crops which plays a significant role in the culture and life of people. Its distribution is seen almost throughout the world and is also commonly known as "Glory of the East". There is hardly any other garden flower which has such diverse and beautiful range of colour, shapes, and height as that of Chrysanthemum. The utility and popularity of chrysanthemum have increased immensely with the introduction of technique of year round production based on scientific research in the field of photo periodism and genetics. In India the usage of chrysanthemums varies between North and South India. In North India they are grown mainly for landscape gardening and for pot culture and in South India they are grown especially for loose flowers, for garland making, hair decoration and offerings to god. Chrysanthemum cultivars exhibits a wide range of diversity in morphological traits like flower number, size, colour and flowering duration. Such wide variations exhibited by the large number of cultivars make the crop suitable for every purpose wished by the end user. Genetic diversity is being used as source of genes in crop improvement for production of high yielding varieties, hybrids and to effect ecologically sustainable economic and social development. In chrysanthemum as a result of numerous cultivars, abundant morphological variation, wide distribution and extremely complicated genetic background, the Investigation, classification, identification and diversity analysis of the cultivars became very difficult. Hence, the present study was an attempt to investigate the extent of divergence among some of the genotypes of chrysanthemum grown in Andhra Pradesh using D 2 analysis. MATERIALS AND METHODS The experimental plant material for the present study comprised of 104 chrysanthemum genotypes planted at Floricultural Research Station, Agricultural Research Institute, Rajendranagar, Hyderabad during and The experiment was laid out in an Augmented Block Design consisting of 10 randomized blocks in each of which four standard chrysanthemum genotypes and ten entries were planted with intra and inter row spacing maintained at 30 x 30 cm. The standard genotypes, namely Raichur, Silper, CO-1 and Punjab Anuradha were served as checks. Observations were recorded on five randomly selected plants for 30 morphological characters. The genetic divergence among the genotypes was quantitatively assessed through Mahalanobis s D 2 statistics (1936) and grouping of the genotypes into different clusters was done by using Ward s minimum variance method as described by Rao (1952). Principal component analysis (PCA) for these thirty characters was performed adopting correlation matrix method according to the procedure described by Banfield (1978) using WINDOWSTAT software package Version 8.1. RESULTS AND DISCUSSION Analysis of variance indicated highly significant differences among the genotypes for all the characters studied indicating the presence of sufficient amount of variability. Based on D 2 analysis, 104 genotypes were grouped into eleven clusters by treating estimated D 2 values as the square of the generalized distance using Ward s minimum 4

2 variance method. Cluster wise distribution of genotypes into eleven clusters was shown in Table 1 and illustrated in fig. 1 with maximum of 31 genotypes in cluster VII followed by cluster III with 15 genotypes and cluster I having 12 genotypes. Figure 1: Clustering pattern in chrysanthemum genotypes based on morphological characters 5

3 Table 1: Average inter and intra cluster (diagonal) distance between 104 genotypes and their distribution on basis of different characters in chrysanthemum Cluster I II III IV V VI VII VIII IX X XI No. of Name of the genotypes genotypes I Ajay, Coffee, Seedling Red, Punjab Anuradha, Asha, Yellow Bonsai, Julie, Dolly pink, Dolly orange, Plants and Seeds choice, Sizuka, Sadhbhavana. II Pink Cascade III Akitha, Shintome, Farr, Red stone, Chocolate Pompon Variegated, Chandrika,Kalyani Mauve, Rajahmundry Selection, Peet Singar, Sukai Sport, N-13, Naintara, Salora, Mallika, Rekha IV Basanthi, Mayuri, Sony, Donald, Terry, Autumn Joy, Meera, Mother Teresa, Vasantika V Anjali, PAU B-107, Winter Queen, Garden Beauty, Perfeeta VI Apurva Singar, Local Button VII Anupam, Priya, Geetanjali, Yellow Star, CO-1, Raja, Freedom, Red Gold, Cloverlee Star, IIHR-13, Yellow Gold, Pankaj, Modella, Punjab Gold, Statesman, Shaffoli, Yokari, Arka Ravi, Yellow Cherub, Harvest House, Aparajitha, CO-3, White, Jaya, Moharaj, Poonam, Silper, Beauty, Lilith, Paragaon Yellow, Flirtation VIII Anupama (L), Ratlam Selection, Royal Purple, Raichur, 9 CO- 2, Tata Centenary, Neelima, Snow Cem, Prof. Harris IX Miss India, Tambra, White Silvercloud, Red Queen, Swan X Jessie Hab Good, Pusa Centenary, Star Pink, Taichen Queen, Red Fair Lady, Skater s Waltz, Robert Earn Shaw, Rose Day, Mr. Whitney XI John Webber, Pride of Maid Fort, Ravi Kiran, Snow Ball, 6 White Snow, Lohagin 6

4 Table 2: Principal Component Analysis showing the contribution of 30 morphological characters among chrysanthemum genotypes % Parameters contribution towards divergence Plant Height (cm) Plant Spread (cm) E-W Plant Spread (cm) N-S No. of Primary Branches/ Plant Petiole Length (cm) Terminal Lobe Length (cm) Leaf Length (cm) Leaf Width (cm) Depth of Sinus (cm) Internodal Length (cm) Days to 1st Flower Bud Appearance Days to 50% Flowering Inflorescence Width (cm) Spray Length (cm) Bud Width (mm) Flower Weight (g) Flower Diameter(cm) Peduncle Length (cm) Peduncle Diameter (mm) Ray Florets/ Head Ray Floret Length (cm) Ray Floret Width (cm) Ray Floret Length : Width Disc Diameter(cm) Disc Florets/ Head Disc Floret Length (cm) No. of Flowers/ Spray No. of Flowers/ Plant Duration of Flowering (days) Suckers/ Plant Eigene Value (Root) % Variance Cumulative % Variance Clusters IV, VIII and X each had nine genotypes in them. While the XI cluster had six genotypes followed by clusters V, IX each bearing five genotypes. The remaining clusters, VI had two genotypes whereas, the II cluster was solitary with only one genotype. The pattern of distribution of genotypes from different eco-geographical 7

5 regions into different clusters with different divergence values was at random, supporting that geographical diversity is not related to genetic diversity. The main forces other than geographical origin responsible for this genetic diversity may be natural/artificial selection, exchange of breeding material, genetic drift and environmental variation. Similar conclusions were drawn by Kavitha and Anburni (2009) in African marigold and Rakesh Kumar et al., (2011) in Snapdragon. Table 3: Cluster means for yield and its components in Chrysanthemum S. Parameters Cluster No. I II III IV V VI VII VIII IX X XI 1. Plant Height (cm) Plant Spread (cm) E-W Plant Spread (cm) N-S No. of Primary Branches/ Plant Petiole Length (cm) Terminal Lobe Length (cm) Leaf Length (cm) Leaf Width (cm) Depth of Sinus (cm) Internodal Length (cm) Days to 1st Flower Bud appearence Days to 50% Flowering Inflorescence Width (cm) Spray Length (cm) Bud Width (cm) Flower Weight (g) Flower Diameter(cm) Peduncle Length (cm) Peduncle Diameter(mm) No. of Ray Florets/ Head Ray Floret Length (cm) Ray Floret Width (cm) Ray Floret Length:Width Disc Diameter(cm) No. of disc Florets/ Head Disc Floret Length(cm) No.of flowers/ Spray No.of flowers/ Plant Duration of Flowering No. of Suckers/ Plant The intra cluster D 2 values among the eleven clusters showed that, the intra cluster D 2 values ranged from 0.00 in cluster II which was represented by single genotype to the maximum of in cluster VI having two genotypes (Table 1) indicating that the genotypes in this cluster were very diverse. The inter cluster D 2 values ranged from to wherein, the lowest inter cluster D 2 value was recorded between cluster III and IV (38.92) while the highest inter cluster D 2 value was recorded between clusters VI and IX (195.87) indicating that crosses may be attempted between the genotypes of cluster VI (Apurva Singar and Local Button) and cluster IX (Miss India, Tambra, White Silver Cloud, Red Queen and Swan) to obtain new desirable recombinants in chrysanthemum. Since all kinds of gene actions and interactions are possible in the expression of quantitative traits it is advisable to make crosses between genotypes selected from the clusters with high mean performance to get desirable transgressive seggregates (Dwivedi and Mitra, 1996) The relative contribution of individual characters towards genetic divergence has been computed and it was revealed that (Table 2) among all the characters, number of ray florets per head contributed maximum to divergence with 51.81% followed by number of disc florets per head (26.10 %) and flower yield per plant (21.06%). Such characters can be given more emphasis for the purpose of fixing priority of parents for hybridization programmes (Ara et al., 2009). The characters viz., days to first flower bud appearance, days to 50 per cent flowering, number of suckers per plant, inflorescence width, duration of flowering and plant height 8

6 contributed to 34.0, 9.0, 7.0, 2.0, 2.0 and 1.0 per cent respectively to the genetic divergence in decreasing order. These results were in good agreement with the findings of Desh raj and Mishra (2000) in gladiolus, Nimbalkar et al., (2006) in Dahlia and Manjunath et al., (2009) in Anthurium. Figure 2: The relative position of Chrysanthemum genotypes based on PCA scores of morphological characters (Three dimensional) Names of the genotypes: 1 Autumn Joy 22 Farr 43 Mother Teresa 64 Ravikiran 85 Sukai sport 2 Ajay 23 Flirtation 44 Mr.Whiteney 65 Red Fair Lady 86 Swan 3 Akitha 24 Freedom 45 N Red stone 87 Taichen 4 Anjali 25 Garden Beauty 46 Naintara 67 Red gold 88 Tambra 5 Anupam 26 Geetanjali 47 Neelima 68 Red Queen 89 Tata Centuary 6 Anupama 27 Harvest house 48 Pankaj 69 Rekha 90 Terry 7 Apurva Singer 28 IIHR Paragaon 70 Robert Earn Shaw 91 Vasantika 8 Arka Ravi 29 Jaya 50 PAU-B Rose Day 92 White 9 Asha 30 Jessie Hab Good 51 Perfeeta 72 Royal purple 93 White silver cloud 10 Aparajitha 31 John webber 52 Peetsingar 73 Sadbhavana 94 White snow 11 Basanthi 32 Julie 53 Pink cascade 74 Salora 95 Winter queen 12 Beauty 33 Kalyani Mauve 54 Plants & seeds choice 75 Seedling red 96 Yellow Bonsai 13 Chandrika 34 Lilith 55 Pride of Maid fort 76 Shaffoli 97 Yellow cherub 14 Choc. Pompon 35 Local Button 56 Priya 77 Shintome 98 Yellow gold Variegated 15 Cloverlee Star 36 Lohagin 57 Prof.Harris 78 Sizuka 99 Yellow star 16 CO-2 37 Mallika 58 Poonam 79 Skater's Waltz 100 Yokari 17 CO-3 38 Mayuri 59 Punjab Gold 80 Snow Ball 101 Raichur 18 Coffee 39 Meera 60 Pusa centenary 81 Snowcem 102 Silper 19 Dolly Orange 40 Miss India 61 Raja 82 Sony 103 CO-1 20 Dolly Pink 41 Modella 62 Rajahmundry selection 83 Star Pink 104 Punjab Anuradha 21 Donald 42 Moharaj 63 Ratlam selection 84 Statesman A large variation in mean performance of genotypes in different clusters was observed as in table 3. Based on multivariate analysis, the cluster-vi had scored high mean values for important economic attributes like plant 9

7 spread in both the directions, inflorescence width, spray length and the important yield contributing characters viz., the number of flowers per spray and number of flowers per plant. Principal Component Analysis In the present investigation, the first eight principal components with eigen values more than one contributed to per cent of cumulative variability among the 104 genotypes of chrysanthemum evaluated for 30 morphological characters (Table 2). The first principal component accounted for per cent of variability while, the second and third accounted for and 9.04 per cent of total variability respectively. The percent of variability from fourth to ninth principal component accounted for 8.02, 5.91, 4.38, 3.73, 3.53 and 2.85 in decreasing order respectively. A three dimensional plot was illustrated in the fig.2 depicting the spatial distribution of 104 chrysanthemum genotypes using principal component analysis score (PCA). Depending upon the inter cluster distance and cluster mean value, the genotypes Apurva Singar and Local Button can be used to derive a broad spectrum of genetic variability in the segregating generations for flower yield per plant, as the magnitude of heterosis depends largely on the degree of genetic diversity of parental lines. REFERENCES Ara Anjum, Raj N, Nazeer A & Tahir S (2009). Estimation of genetic divergence for yield and quality traits in tomato (Lycopersicon esculentum M). Vegetable Science, 36(3) Banfield CF (1978). Principal Component Analysis for Genstat. Journal of Statistics and Computer Simulation, Desh Raj & Mishra RL (2000). Genetic divergence for economic characters in gladiolus under different environments. Journal of Ornamental Horticulture, 3(1) Dwivedi AK & Mitra SK (1996). Divergence analysis of litchi (Litchi chinensis Sonn) cultivars grown in West Bengal. Indian Journal of Genetics, Kavitha R & Anburani A (2009). Genetic diversity in African marigold (Tagetes erecta L.) genotypes. Jouranl of Ornamental Horticulture, 12(3) Mahalanobis PC (1936). On the generalized distance in statistics. Proceedings of National Institute of Sciences, India Manjunath S, Patil A Swath C & Kumar DP (2009). Multivariate analysis and the choice of parents for hybridization in anthurium (Anthurium andreanum L). Journal of Ornamental Horticulture, 12(2) Nimbalkar CA, Dhane AV & Bajaj VH (2006). Divergence studies in Dahlia. Journal of Ornamental Horticulture, 9(2) Rakesh K, Santosh K, Prabhat K & Rakesh M (2011). Genetic variability and divergence analysis in snapdragon (Antirrhinum majus L.) under tarai conditions of Uttarakhand. Progressive Horticulture, 43(2) Rao CR (1952). Advanced Statistical Methods in Biometrical Research. John Wiley and Sons Inc., New York