IN VITRO SCREENING OF TOMATO (Solanum lycopersicum L.) GENOTYPES FOR DROUGHT TOLERANCE USING POLAYETHELENIE GLYCOL

Abstract

The experiment was conducted to study genetic diversity analysis of tomato (Solanum lycopersicu,n L.) under drought condition in vitro. Fourteen tomato genotypes were used as experimental materials among which I3ARI Tomato 2, BAR! Tomato -II are parent material and rest of all were lines, and they were I3ARI Tomato-2, BAR! Tomato-Il, 130-7260, l3!)-7290, BD-7295. 13l)-7286, BD- 7269, 130-7258, BD-7299, 13l)-7292. BD-7291, 13l)-7302, 13D-7301 and BD-7762. Murashige and Skoog medium were used with different PEG concentration as culture medium for root and shoot regeneration. The longest length of root (2.83 cm) was recorded for 0 g PEG, whereas the shortest length (1.88 cm) was observed in 60 g PEG. In an average, among the different genotypes of tomato the highest length of root (5.01 cm) was recorded from BARI-2 and the lowest length of root (0.69 cm) in BAR!- 1. Among the studied genotypes BARI-2, Bl)-7258, BD-7301 and BD-7762 produced the highest plant weight in 40 and 60 g PEG compared to 0 and 20 g PEG. In an average among the different genotypes of tomato the highest weight of plant (0.068 g) was recorded from BARI-2 and 13D-7290 and the lowest weight of plant (0.003 g) was found in I3ARI-1 I and BARI-7292. Cluster I and IV was the largest cluster comprising of 5 genotypes followed by cluster II with 3 genotypes and cluster III belongs only I genotypes of tomato. In considering of clustering mean for initial length the highest mean was 1.49 for cluster IV. In ease of length highest cluster mean 6.53 was recorded in cluster Ill and 11w plant weight highest cluster 0.066 was observed in cluster Ill. The rcsults revealed that genotypes chosen for hybridization from clusters with highest distances would give high heterotie F1 and broad spectrum of variability in segregating generations.