Drought tolerance studies in tomato Lycopersicon esculentum MILL

Abstract

Drought tolerance studies in tomato were undertaken at K.R.C. College of newlineHorticulture Arabhavi during 2003-2005. Initially, 50 tomato genotypes were screened for newlinedrought tolerance based on the per cent reduction in 0.4 over 1.2 IW/CPE for biophysical, newlinebiochemical and morphological characters. Based on the 1st year results 11 genotypes newlineconsisting of eight tolerant two susceptible and one check were selected for detailed newlineinvestigation under stress with above traits in addition to root studies during second year. newlineResults of pooled analysis indicated that, under the sever moisture stress of 0.4 newlineIW/CPE ratio, higher yield was noticed in the genotype S-22 (40.43 t.ha-1) as compared to newlinesusceptible genotype L-28 (17.88 t.ha-1). Least per cent reduction in yield per plant at 0.4 newlineover 1.2 IW/CPE ratio was found in the genotype L-38-1 (11.45%) whereas maximum yield newlinereduction was observed in the genotype L-28 (67.18%). Biomass production was significantly newlinehigher in the genotypes L-10 (P), S-22 and L-30 at all the growth stages as compared to newlinelocal check Arka Meghali and other susceptible genotypes. Among the biochemical traits, newlinechlorophyll a and proline content was maximum in the genotype L 10 (P) whereas, newlinechlorophyll b total chlorophyll and ascorbic acid content were higher in the genotype L-30. newlineTSS content was more in the genotype GK-3 while lycopene was higher in IIHR 2274. newlineNumber of pubescence on adaxial and abaxial surface was significantly higher in the L-30. newlineSignificantly higher root to shoot ratio, root length and root density at 45 DAT, newlineincluding higher pollen viability at 300C in the drought tolerant genotype IIHR 2274. However, newlinemaximum pollen viability at 250 C was recorded in the genotype L-30 and at 350 C it was in newlinethe genotype L-40-1. newlineHence, considering pollen viability, biochemical, growth, yield and quality parameters newlineit can be inferred that genotypes S-22, L-10 (P), L-40-3, IIHR 2274, L-38-1 and L-30 newlineperformed better under drought conditions and could be catagorised as drought tolerant newlinegenotypes compared t