Genetic diversity, heritability, genetic advance and correlation coefficient in guava (Psidium guajava']java)

A study was conducted during 2003-05 to evaluate genetic diversity, heritability, genetic advance and correlation coefficient of some promising selections of guava (Psidium guajava L.) with the commercial varieties under Indo-Gangetic region of Uttar Pradesh. Wide range of plant height (3.40-6.80 m), leaf length (8.20-13.90 cm), size of flower (2.31-4.63 cm), pollen grain size (18.01-26.80 mu), fruit length (8.46-14.41 cm), fruit diameter (3.00-18.15 cm), fruit weight (34.01-290.26 g) and days required to fruit maturity (116-177 days) were observed. Among the qualitative traits, the range of total soluble solids (10.48-21.26%), acidity content (0.23-1.33%), total sugar content (7.46-14.36%), reducing sugar (3.65-8.44%), non-reducing sugar (3.53-8.52%), ascorbic acid content (79.38-517-68 mg) and seeds/fruit (26.89-115.85) were recorded. Heritability of the parameters was very high and range was 75.18 (size of flower) to 99.00 (reducing sugar content). Genetic advance range was recorded between 0.270 (length of fruit) and 1.423 (weight of fruit). Genotypic covariance range was between 12.144 (pollen grain size) and 70.43 (weight of fruit). Phenotypic covariance range was found in between 12.208 (days required to fruit maturity) and 71.768 (weight of fruit). Phenotypic correlation coefficient was positive with fruit diameter, weight of fruit, days required to fruit maturity and TSS with size of flower. Seeds/fruit had positive correlation with acidity content. Total soluble solids had positive correlation with acidity content, total sugar content, reducing sugar and non-reducing sugar content.