Identification of Contrasting Germplasm Accessions of Tomato (Lycopersicum esculentum L.) for Root Architecture and Intrinsic Tolerance at Cellular Level

摘要

Due to limited availability of aerable land and the high market demand for vegetables around the world, solanaceous (eggplant, pepper and tomato) crops are cultivated under unfavourable soil and environmental conditions leading to reduced quality andproductivity of crops. One way to avoid or to reduce losses in production and productivity of vegetable crops from environmental stresses (drought) would be to graft them onto rootstocks capable of reducing the effect of external stresses on the shoot. In order to achieve this, identification of suitable root stock having superior root characteristics with higher level of root cellular level tolerance (CLT) is highly relevant under drought stress condition. In this context, 100 tomato accessions were evaluated in specially constructed root structures following augmented block design under normal conditions to study the genetic variability for root architecture viz., root length (cm), root volume (cm3), root dry weight (g) and intrinsic tolerance at cellular level (TTC). Study indicated a wide and significant variation among the accessions for all the root traits, intrinsic tolerance and also for ancillary traits. Based on root dry weight, total biomass and intrinsic tolerance, 6 contrasting lines of tomato were identified and further evaluated under different levels of moisture stress and finally root stock donors were identified for grafting approach.