Comparative Study of Sapota Varieties and Hybrids for Tolerance and Susceptibility against Seed Borer (Trymalitis margarias Meyrick)

Abstract

The performance of 23 sapota varieties/hybrids was tested for their ability to withstand seed borer Trymalitis margarias Meyrick at
Fruit Research Station, Navsari Agricultural University, Gandevi, Gujarat. The varietal deviation for five consecutive years (2015-16 to
2019-20) showed that Kirthibarthi had a higher fruit infestation of 7.47% than the standard check Kalipatti (6.89%), as well as being
more sensitive to DHS-2 (6.58%), CO-2 (6.56%), and Cricket balls (5.89%). In contrast, Chala collection-1, Chala collection-3, Chala
collection-2, Zumakhiya, CO-3 and CO-1, all exhibited infestation level less than 4%. Fruit damage intensity was highest during the
initial phase of fruit harvesting in December, reaching 8.64, 7.94, and 7.67% in Kirthibarthi, Kalipatti, and CO-2, respectively.
Nonetheless, DHS-2 (8.54%) and Cricket ball (6.97%) suffered the most damage in February during the middle phase of fruit
harvesting. However, a non-significant correlation was revealed between seed morphology viz., length, width and thickness, as well
as eight biochemical contents of the seed and pest infestation. Due to late flowering and ultimately fruiting initiation, escape-type
resistance was seen in less damaged sapota varieties/hybrids.