IN-VITRO SCREENING OF DIFFERENT TOMATO GENOTYPES AGAINST PEG INDUCED WATER STRESS

Abstract

Tomato (Lycopersicum esculentum L.) is one of the most economically important plants in the Solanaceae family. Water scarcity is one of the major climatic constraints which is affecting all crops including tomato in the world. Selection of water stress tolerant cultivars is an important strategy to overcome this problem. Therefore the present research was conducted to determine the effect PEG induced water stress on germination percentage and early growth stages of tomato seedlings. Fifteen different tomato genotypes were screened under in-vitro conditions using two different concentrations of PEG (2% and 4%). The experiment was arranged in a completely randomized design (CRD) with three replications. Parameters like germination percentage (%), root length (cm), shoot length (cm) and seedling biomass (g) were recorded during the experiment. Results indicated that PEG induced water stress significantly reduced germination percentage (%) and other growth parameters in drought susceptible tomato genotypes (RUS-1, Rustam, R-2017, Pakit, 17904, Kashmiri, Kiara, Avinash, and K.K.2). Whereas in other genotypes “R. Wonder, Naqeeb, Rio grande, T-4, Patfeeder and Nagina” all parameters increase with an increase in PEG concentration. However among these genotypes, “Patfeeder” exhibited highest germination percentage (100 %) with maximum root and shoot length and seedling biomass at highest PEG concentration 4%. Based on experimental results, “Patfeeder” was considered a drought tolerant genotype due to its better performance in different levels of water stress.