Study of genetic variability , heritability and genetic advance for fruit quality characters in Teasle gourd ( Momordica subangulata blume . subsp . renigera )

Five female clones of Teasle gourd were evaluated to estimate the variability, heritability and genetic advance in randomized complete block design with four replications. Higher phenotypic coefficients of variation were observed for all the characters except fruit length at marketable stage. Total sugar in mesocarp, total sugar in exocarp, reducing sugar in mesocarp, ascorbic acid in exocarp, ascorbic acid in mesocarp, total soluble solids (TSS) in exocarp, b-carotene in exocarp, acidity in mesocarp, bcarotene in mesocarp, TSS in mesocarp, acidity in exocarp showed high heritability coupled with high genetic advance indicating that these traits were under the additive gene control and simple selection can be used for further improvement in these traits Teasle gourd.


INTRODUCTION
Teasle gourd (Momordica subangulata Blume.subsp.renigera) is one of the most important members of the cucurbitaceae, which is diecious in nature and contains good flavor aroma and essential oil and is used in almost all the vegetarian and non vegetarian communities of the world (Bhuiya et al., 1977).The young leaves of Teasle gourd are also consumed as a leafy vegetable.Teasle gourd seeds contain oil which is used as an illuminant.The fruits are regarded as highly nutritious.The unripe fruits act as appetizer and astringent.Since Teasle gourd is a commercial crop and is multiplied through root propagated, thus, it was thought imperative to evaluate different germplasm of Teasle gourd.Estimates of various parameters for assessment of genetic variability viz., mean range of variation, heritability, genetic advance and coefficients of variation help the plant breeders in devising suitable plant type by bringing improvement in *Corresponding author.E-mail: abhishek.hort@gmail.com.quantitatively inherited traits.Systematic breeding efforts on this crop have so far been neglected.For starting any improvement work, information about the genetic variability in the population is a prerequisite.Presence of high variability in this crop offers much scope for its improvement.Hence, an attempt was made to estimate genetic variability, heritability and genetic advance in the available germplasm of Teasle gourd.

MATERIALS AND METHODS
The experimental materials consisted of five female clones of Teasle gourd grown in Randomized Complete Block Design with four replications during 2007 to 2008 were carried out at the research field of All India Coordinated Project on Vegetable Crops situated at C Block farm, Bidhan Chandra Krishi Viswavidyalaya, Nadia.Recommended package of practices were followed to raise healthy crop.Five competitive plants of each genotype were selected randomly in each replications for recording observations on exocarp, acidity in mesocarp, b-carotene in exocarp, reducing sugar in mesocarp, ascorbic acid in excoarp,b-carotene in mesocarp, ascorbic acid in mesocarp, TSS in exocarp, reducing The mean data were subjected to statistical analysis of variance (Panse, 1957), coefficient of variation and heritability (Burton and Devane, 1953) and genetic advance in percent of mean (Johnson et al., 1955), respectively.

RESULTS AND DISCUSSION
The analysis of variance revealed significant differences among the genotypes for all the seventeen characters, thus paving way for further analysis.The mean values and estimates of different quality parameters for various traits are given in Table 1.Wide range for all the traits indicates the existence of variation among the genotypes.The phenotypic coefficient of variation (PCV) was high for total sugar in mesocarp, followed by total sugar in exocarp, acidity in mesocarp, b-carotene in exocarp, reducing sugar in mesocarp, ascorbic acid in excoarp, b-carotene in mesocarp, ascorbic acid in mesocarp, total soluble solids (TSS) in exocarp, reducing sugar in excoarp, acidity in exocarp, fruit breadth at marketable stage, TSS in mesocarp, ovary diameter, pericarp thickness at marketable stage, fruit weight at marketable stage.
The similar trend was observed for genotypic coefficient of variation (GCV).Although GCV is an indicative of the presence of high degree of genetic variation, the amount of heritable variation, can only be determined with the heritability estimates and genetic gain.Broad sense heritability estimates was moderate for pericarp thickness at marketable stage and fruit length at marketable stage and high ranging for other characters.The results are in partial agreement with those reported by Burton (1952) and Hayes et al. (1955).Though high heritability indicates the effectiveness of selection on the basis of phenotypic performance, it does not show any indication the amount of genetic progress for selecting the best individuals.
The genetic advance (%) was moderate for all the characters except fruit length at marketable stage, fruit breadth at marketable stage and pericarp thickness at marketable stage.Total sugar in mesocarp, total sugar in exocarp, reducing sugar in mesocarp, ascorbic acid in excoarp, ascorbic acid in mesocarp, TSS in exocarp, b-carotene in exocarp, acidity in

Table 1 .
Genetic variability parameters for different fruit quality characters of Teasle gourd.