Collection, conservation, evaluation and use of durian germ plasm at Horana

Abstract

Unavailability of high quality varieties is one of the constraints in commercial durian production. Aprogram to collect durian gerrnplasm was initiated at Horana. Fruits from 26 seedling trees wereevaluated for fruit weight. number of arils, number of seeds, weight of husk and seeds using six fruitper tree. Aril size, seed size, % rind, % seed and % aril were calculated. Aril color, flavor and overallacceptability were also recorded with a panel test. Results showed high variability in fruit quality traitsexists among trees. Highest variabil ity was found in number of seeds per fruit (CV=36.2%) while %rind showed the lowest variability (CV=7.26%). Number of seeds varied from 3.7 -19.2 per fruitwhile % rind varied from 60.5-79.5%. Nine accessions selected were planted with five replicates forfurther evaluation. Plant height and stem girth showed significant differences at early stages butbecame non significant by three years after planting. At 42 months after planting plant height variedfrom 368-492 ern while stem girth ranged from 42.0 - 52.8 cm. Principal component analysis ofseiected fruit and leaf characteristics of six accessions showed that first three PCs accounted for89.35% of the variation in the characteristics used for the analysis indicating that the varieties of thecollection are diverse. Collection of gerrnplasrn continued with establishment of a field gene bank toconserve accessions with two replicates. Nine selections were also further tested in farmer fields foradaptability.