INTRODUCTION Gerbera (Gerbera jamesonii Bolus ex Hooker F.) is one of the most beautiful cut flowers with exquisite shape, size and colour with over 40 species of Asiatic and African origin. Gerbera is a dwarf herbaceous perennial plant belonging to the family Asteraceae. It is a diploid, with somatic chromosome number 2n = 50. The modern gerbera arose from G. jamesonii hybridized with G. viridifolia and, possibly, other species. Gerbera is among the top ten cut- flowers traded in the global market. There is a good demand for these flowers both in the domestic and export markets. As commercial cultivation of the cut-flowers has a good potential, introduction and popularization of high-yielding cultivars of gerbera has gained importance. However, no systematic efforts have been made in the past to identify cultivars of gerbera suitable for cut-flower production under protected conditions in the Shevaroy hills. Keeping this in view, 36 cultivars of gerbera were collected and evaluated to identify gerbera cultivars suitable for the region. MATERIAL AND METHODS An experiment was conducted under polyhouse at Horticultural Research Station, Tamil Nadu Agricultural University, Yercaud, between 2008 and 2010. The Evaluation of commercial cultivars of cut gerbera (Gerbera jamesonii Bolus ex Hooker F.) under polyhouse in Shevaroy condition of Eastern Ghats M. Anand, A. Sankari and R. Arulmozhiyan Horticultural Research Station, Yercaud - 636 602, India E-mail: anandhort@yahoo.com ABSTRACT An investigation was carried out to evaluate performance of 36 cultivars of cut gerbera (Gerbera jamesonii Bolus ex Hooker F.) in a polyhouse at Horticultural Research Station, Tamil Nadu Agricultural University, Yercaud, during 2008-2010. Significant differences were observed for all the characters studied. Maximum plant-spread (78.02cm) was observed in cv. Robusta. Higher number of leaves was recorded in cv. White Tibet (41.54). Maximum Leaf length and leaf width was recorded in cvs. Golden Gate and Yanara. Maximum number of suckers produced was recorded in cv. Junkfru (7.60). Maximum stalk length was observed in cv. White Tibet (62.62cm), while flower diameter, cut flower production and vase-life were higher in cv. Rosalin. Correlation and path coefficient analysis showed that plant height, number of leaves per plant and number of suckers per plant were the important components of cut-flower yield in gerbera. It may be concluded that cultivars Rosalin, White Tibet, Junkfru and Golden Gate were found to be the best for floral quality and yield, and are recommended for cut-flower production under Shevaroy condition of Eastern Ghats. Key words: Gerbera, evaluation, correlation, path coefficient J. Hortl. Sci. Vol. 8(2):199-203, 2013 experimental site is geographically located between 11°04" and 11°05" North latitude and 78°05" to 78°23" East longitude, at an altitude of 1500m above Mean Sea Level. Average maximum and minimum temperatures are 31.0oC and 12.4oC, respectively. Mean annual rainfall in Yercaud is 1572mm, and average relative humidity 75%. The soil of the experimental plot was laterite in texture, at 0.5 to 1.5m depth, pH 6.25 and EC 0.037 dSm. The plot was thoroughly pulverized and enriched with red soil, sand and well- decomposed farm yard manure in 2:1:1 proportion. The polyhouse was fumigated with methyl bromide (30g/m2). The experiment was laid out in Randomized Block Design, with three replications. Thirty six cultivars with uniform- sized suckers (4-5 leaves) were collected from different sources (Table 1) and planted in May 2008 at a spacing of 30 x 30cm. Length, breadth and height of the polyhouse was 23m, 12m and 7.5m, respectively. Five plants per replication in each cultivar were used for recording observations on plant spread, leaf length, leaf breadth, number of leaves/plant, number of suckers/plant, days taken to flowering, stalk length, flower diameter, number of flowers/plant/year and vase-life. Genotypic and phenotypic correlation coefficients were calculated as per Panse and Sukhatme (1967). Parameters of variability were calculated 200 as per the formula of Burton and De Vane (1953). Heritability, genetic advance and expected genetic gain were calculated by the formula suggested by Jhonson et al (1955). Mean and Standard Error were worked out as per standard methods, and coefficient of variation was computed. Path coefficient was worked out owing genotypic correlation coefficient. RESULTS AND DISCUSSION All the genotypes showed significant differences for vegetative characters (Table 2). Greater plant-spread was recorded in cvs. Rosalin (78.02cm) and White Tibet (71.94cm); minimum was observed in cv. Essandre (37.49cm). Difference among the cultivars could be due to leaf size variation. These results are in accordance with findings of Rajiv Kumar and Yadav (2005), and Thomas et al (2004). More number of leaves were produced by cvs. White Tibet (41.54), Rosalin (35.46) and Golden Gate (35.46). Leaf length and leaf width influence flower yield too, as these are important parameters influencing plant spread. Longest leaf was recorded in cv. Golden gate (29.62cm), while the shortest in cv. Goldy (14cm). Cultivar Golden Gate was found to produce broader leaves, and Yanara narrower leaves. Difference in various growth parameters may be attributed to inherent genetic characters of the cultivar (Luna and Mahumita, 2009). Among the cultivars, higher number of suckers was recorded in cvs. Junkfru, (7.60) and Rosalin (6.90), while Table 1. Source of gerbera cultivars Cultivar Source Aida KF Biotech Amaretto SPIC Biotech Arobella KF Biotech Avemeria SPIC Biotech Blondy Private Nursery Bondana Private Nursery Dalma KF Biotech Dolcerita Private Nursery Essandre SPIC Biotech Florida SPIC Biotech Golden Gate KF Biotech Goldy Private Nursery Junkfru Private Nursery Kalika Private Nursery Lily Private Nursery Marmara SPIC Biotech Marshsal SPIC Biotech Mini Private Nursery Oilila Private Nursery Oranila KF Biotech Piton Private Nursery Red Bull Private Nursery Red Ventura Private Nursery Ringo Private Nursery Rosalin KF Biotech Rosabella Private Nursery Ruby Red Private Nursery Sunway KF Biotech Skylina SPIC Biotech Verseck Private Nursery Vojavir Private Nursery Thalassa KF Biotech Tiffany Private Nursery White Tibet Private Nursery Woman SPIC Biotech Yanara SPIC Biotech Table 2. Evaluation of gerbera cultivars for growth attributes under Shevaroy conditions Cultivars Plant Leaf Leaf Number Number Days spread length width of of taken to (cm) (cm) (cm) leaves/ suckers/ flowering plant plant Aida 56.75 15.00 5.33 16.21 5.58 130.67 Amaretto 59.44 19.00 4.90 18.24 5.58 134.67 Arobella 50.16 21.62 4.00 30.40 5.07 116.67 Avemeria 50.67 22.00 4.50 25.33 4.56 123.67 Blondy 49.76 18.00 3.70 39.52 5.27 139.00 Bondana 42.56 21.00 5.90 27.36 6.49 134.67 Dalma 43.07 15.00 6.10 29.39 5.67 113.67 Dolcerita 38.51 19.50 5.00 31.41 4.05 126.67 Essandre 37.49 21.00 5.00 39.52 3.95 127.67 Florida 58.27 16.50 5.14 22.29 5.98 139.00 Golden Gate 67.04 29.62 7.10 35.46 5.67 115.67 Goldy 59.79 14.00 5.26 29.39 3.55 117.67 Junkfru 66.71 25.00 6.70 38.50 7.60 116.67 Kalika 63.84 16.50 3.50 22.29 3.55 121.33 Lily 42.15 14.10 5.77 29.37 3.98 125.33 Marmara 48.14 16.00 5.90 31.41 4.56 123.67 Marshsal 61.81 23.00 5.50 32.43 3.55 126.67 Mini 53.71 23.00 5.70 25.33 4.56 117.67 Oilila 70.59 25.00 6.40 31.41 6.99 134.67 Oranila 61.98 23.50 3.80 31.41 4.56 109.67 Piton 49.65 21.00 5.40 17.23 3.55 145.00 Red Bull 43.57 23.00 5.90 33.44 4.05 129.67 Red Ventura 63.84 17.50 5.00 23.31 5.32 121.33 Ringo 50.67 21.00 5.10 21.28 4.19 127.67 Rosalin 78.02 23.66 6.50 35.46 6.90 120.33 Rosabella 44.08 22.00 4.40 33.44 3.55 133.67 Ruby Red 59.45 23.00 6.40 33.44 6.48 145.00 Sunway 56.75 17.00 4.83 33.44 4.76 120.33 Skylina 42.56 19.00 5.70 34.45 4.96 129.67 Verseck 45.72 20.00 5.89 24.32 5.21 135.67 Vojavir 50.87 15.25 5.37 20.27 5.20 128.67 Thalassa 57.76 20.00 4.50 29.39 4.66 126.67 Tiffany 38.51 25.00 3.60 21.28 3.55 133.67 White Tibet 71.94 22.50 6.20 41.54 6.18 127.67 Woman 39.52 19.00 4.90 39.52 4.56 134.67 Yanara 41.55 23.50 3.20 23.31 4.05 144.00 SEm 2.3 0.37 0.19 1.27 0.42 5.37 CD (P=0.05) 4.7 0.74 0.39 2.53 0.21 10.72 J. Hortl. Sci. Vol. 8(2):199-203, 2013 Anand et al 201 Rosalin produced the longest stalk, while cultivars Dalma and Florida produced the shortest. Similar variations have been earlier observed by Kandpal et al (2003) in cut- gerbera. Diameter of the flower was highest in cv. Rosalin (11.7cm) and White Tibet (11.45cm), while cv. Mini had the lowest flower diameter (5.47cm). This is perhaps due to the inherent character of the individual variety. These findings are in accordance with results of Luna and Mahumita (2009) who reported large difference in flower- diameter of different gerbera cultivars grown under greenhouse conditions. Number of cut-flowers per plant varied from 24 to 48 flowers per plant per year. Cultivar Rosalin produced the highest number of cut-flowers (48), followed by White Tibet (40). Minimum number of cut-flowers were produced by Dalma (23). Longest vase-life of cut-flower in water was recorded in cv. Rosalin (11.33 days). Analysis of Variance revealed that mean square of treatments was significant for most of the characters, indicating varietal differences in all the characters studied (Table 4). Estimates for phenotypic coefficient of variance (PCV) were found to be higher than genotypic coefficient of variance (GCV) for all the seven characters studied indicating, that, the apparent variation was not only due to the genotype but also due to influence of the environment in expression of the genotype. These results are in agreement with Chobe et al (2010). A close correspondence was seen between GCV and PCV for number of leaves, number of suckers per plant, flower diameter and number of flowers, indicating little influence of environment on these characters. Estimates for heritability in the broad sense gives a measure of transmission of characters from one generation to another, thus, giving an idea of the heritable portion of variability, and enabling the plant breeder isolate elite selections in the crop. In the present study, number of flowers per plant had high heritability values along with genetic advance of mean, followed by number of suckers per plant and number of leaves. Thus, selection on the basis of number of flowers per plant, number of suckers per plant and number of leaves would be more effective in further breeding programmes. Chobe et al (2010) reported high heritability along with genetic advance as per cent of mean for number of days to first flowering, stalk length and number of flowers per plant. Anoop Kumari et al (2011) reported high heritability, along with lower genetic advance, for number of suckers and flower diameter, thereby exhibiting non-additive gene effects. Table 3. Evaluation of gerbera cultivars for floral characters under Shevaroy condition Cultivars Stalk Flower Number of Vase-life length diameter flowers/plant/ (days) (cm) (cm) year Aida 38.91 8.51 24.00 6.00 Amaretto 43.68 9.22 24.00 9.33 Arobella 49.76 5.88 36.00 10.33 Avemeria 43.57 8.51 24.00 10.33 Blondy 46.01 7.29 24.00 7.00 Bondana 48.03 9.02 36.00 9.33 Dalma 35.36 7.91 24.00 9.33 Dolcerita 51.48 8.41 24.00 8.33 Essandre 49.15 8.31 36.00 10.33 Florida 35.77 7.29 24.00 9.33 Golden Gate 50.86 9.50 36.00 8.33 Goldy 46.72 6.99 24.00 9.33 Junkfru 57.05 10.64 36.00 8.33 Kalika 41.35 8.92 24.00 8.33 Lily 42.09 6.51 32.00 7.33 Marmara 42.46 10.13 24.00 9.33 Marshsal 52.39 6.28 24.00 9.33 Mini 38.91 5.47 36.00 8.33 Oilila 54.21 8.51 36.00 10.33 Oranila 54.62 9.32 36.00 9.33 Piton 46.11 8.51 24.00 8.33 Red Bull 39.72 10.33 24.00 10.33 Red Ventura 45.19 10.33 24.00 10.33 Ringo 37.90 8.51 36.00 8.33 Rosalin 58.17 11.75 48.00 10.33 Rosabella 39.72 7.60 36.00 9.33 Ruby Red 50.66 7.39 36.00 10.33 Sunway 48.74 8.11 24.00 8.33 Skylina 41.95 9.53 24.00 10.33 Verseck 40.84 10.03 36.00 10.33 Vojavir 38.10 9.63 24.00 9.33 Thalassa 51.78 6.59 24.00 9.33 Tiffany 50.87 8.51 24.00 10.33 White Tibet 62.62 11.45 40.00 10.33 Woman 47.93 9.83 36.00 10.33 Yanara 42.86 8.11 24.00 9.33 SEm 2.20 0.42 1.29 0.46 CD (P=0.05) 4.39 0.83 2.58 0.92 cvs. Goldy, Rosabella, Tiffany and Piton produced lower number of suckers per plant. Similar variations in sucker production among cultivars of cut-gerbera was also reported earlier by Rajiv Kumar and Yadav (2005), and Sarkar and Ghimiray (2004). Least number of days taken to flowering was recorded in cv. Oranila (109.67 days), followed by cv. Dalma (113.67 days). The least number of days taken to flowering was recorded in cv. Ruby Red (145.0 days). On perusal of data presented in Table 3, it is seen that floral characters differed significantly among cultivars. Stalk length is one of the most important characters considered in grading cut-flowers. Cultivars White Tibet and J. Hortl. Sci. Vol. 8(2):199-203, 2013 Evaluation of cut gerbera cultivars under polyhouse 202 In the present study, it was observed that genotypic correlation coefficient was higher than phenotypic correlation coefficient for most of the characters under study (Table 5). Similar trend was observed also by Magar et al (2010) in cut-gerbera for most of the characters. These findings indicate that though there is a strong, inherent association between various characters, phenotypic expression is reduced under the influence of environment. In some cases, phenotypic and genotypic correlations were very close, indicating less influence of environment. In the present study, genotypic correlation between number of flowers per plant per year was positively correlated with plant height (0.145), number of leaves (0.241), number of suckers (0.188) and stalk length (0.200) and were positively correlated, while, the days to first flowering and flower diameter showed a negative correlation with yield. This is in line with results of Magar et al (2010). Path coefficient analysis revealed that plant height, number of leaves, number of suckers and stalk length had a positive effect on yield (Table 6), while this was negative for days to first flowering and flower diameter. Direct effect was the highest for plant height, followed by stalk length and number of leaves. Number of leaves had the highest indirect effect on number of flowers/plant/year through days to first flowering. Considering correlation and path coefficients, plant height, number of leaves per plant and number of suckers per plant emerged as the important components of cut-flower yield in gerbera. This is in agreement with results of Hasanuzzaman (2006). It may be concluded from the present investigation that of the 36 cultivars evaluated under polyhouse condition, cultivars Rosalin, White Tibet, Junkfru and Golden Gate were the best, with superior qualities for cut-flower production under Shevaroy condition of Eastern Ghats. Table 4. Analysis of genetic parameters for quantitative traits in gerbera Character Range Mean PCV GCV ECV Heritability GA(%) (%) (%) (%) (h2) % of Mean Plant height (cm) 22.09 - 28.37 25.49 7.84 5.91 5.15 56.90 9.19 Number of leaves 16.21 - 41.54 29.22 25.13 24.05 7.29 91.58 47.41 Days to flowering 109.67 - 145 127.75 8.18 6.35 5.16 60.25 10.15 Number of suckers 3.55 - 7.60 4.95 22.74 22.13 5.25 94.66 44.35 Stalk length (cm) 35.77 - 62.62 46.27 15.10 13.93 5.84 85.06 26.46 Flower diameter (cm) 5.47 - 11.75 8.58 18.14 17.12 6.00 89.07 33.29 Number of flowers / plant /year 24.00 - 48.00 29.67 23.29 22.67 5.35 94.71 45.44 Table 6. Path co-efficient analysis for cut gerbera Character Number of Days to Number of Stalk Flower No. of leaves flowering suckers length diameter flowers / (cm) (cm) plant /year Number of leaves 0.24881 0.02556 0.02463 0.01306 -0.02052 0.24881 Days to flowering 0.04515 -0.14084 -0.00105 -0.09251 -0.04929 -0.14084 Number of suckers 0.09602 0.00231 0.06383 -0.04765 0.03445 0.06383 Stalk length (cm) 0.0103 0.04131 -0.00964 0.31537 -0.10227 0.31537 Flower diameter (cm) -0.01191 -0.01619 -0.00513 0.07521 -0.42884 -0.42884 Table 5. Genotypic and phenotypic co-efficient of correlation for yield attributing parameters in gerbera Character Number Days to Number of Stalk Flower No. of of leaves flowering suckers length diameter flowers / (cm) (cm) plant /year Number of leaves Genotype 1 0.181 0.386 0.041 0.048 0.241 Phenotype 1 0.165 0.372 0.042 0.038 0.238 Days to flowering Genotype 1 -0.016 -0.293 0.115 -0.276 Phenotype 1 0.129 0.003 0.262 -0.114 Number of suckers Genotype 1 -0.151 -0.08 0.188 Phenotype 1 -0.059 -0.009 0.211 Stalk length (cm) Genotype 1 0.238 0.200 Phenotype 1 0.333 0.201 Flower diameter (cm) Genotype 1 -0.292 Phenotype 1 -0.254 No. of flowers / plant / year Genotype 1 Phenotype 1 J. Hortl. Sci. Vol. 8(2):199-203, 2013 Anand et al 203 REFERENCES Anoop Kumari, Patel, K.S. and Mahesh Choudhary. 2011. Genetic variability studies in gerbera, Res. Pl. Biol., 1:01-04 Burton, G.W. and De Vane, E.H. 1953. Estimating heritability in tall fescue (Festuca arundinacea) from replicated clonal material. Agron. 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