Deciphering the Morphological, Physiological and Biochemical Mechanism Associated with Drought Stress Tolerance in Tomato Genotypes

Abstract

Abiotic stresses are one of the key limitations to global crop production and food security. Among the abiotic stresses, drought is one of the most vital factors that causes change in morphological, biochemical and physiological characteristics in plants, and consequently affects the growth and productivity of crops. The main purpose of the present study was to evaluate the effect of drought on morphological [Plant height, root length (cm), shoot length (cm), number of branches, yield attributing traits], physiological ratio of root/shoot length, leaf area (cm 2 ), relative water content (%), and electrolyte leakage (% conductivity) and biochemical traits [ascorbic acid content (mg/100g), total carotenoids (mg/100g), total chlorophyll content, proline, sugar content] in 15 tomato genotypes and to identify drought stress tolerant genotypes. The results confirmed that there are significant variations in agronomic, physiological and biochemical parameters among 15 tomato genotypes under drought and irrigated conditions. Among the 15 genotypes, EC-317-6-1 and WIR-4360 were found highly tolerant to drought in comparison to others while Kashi Amrit and Kashi Sharad were found susceptible to drought conditions. The performance of tomato genotypes used in the study showed significant differences in all studied traits, suggesting that they could be taken into account when selecting for drought tolerance. EC-317-6-171 and WIR-4360 had good yield performance under deficit irrigation treatment. Moreover, results indicate that biochemical and physiological parameters are more useful for the screening of drought tolerant tomato genotypes.

Traits Associated with Drought Tolerance in Tomato (Solanum lycopersicum L.)

“…The present study showed that leaf RWC was reduced under drought stress in the both genotypes. A similar results also observed by [17]. However, SL CBE G 26 showed a less reduction compared to SL CBE 23, indicating the increased root length might favoured increased water uptake from the deeper layers of soil.…”

Estimates of Genetic Variability, Association Studies and Per se Performance of Tomato Genotypes for Growth and Yield Parameters Under Drought Stress Conditions

“…The mean number of fruits per plant (20.53) average fruit weight (28.57 gm) and fruit yield per plant (0.73 kg) were considerably reduced when compared to well-irrigated conditions (31.64 fruits, 42.84 gm, and 1.36 kg, respectively) with a percent reduction of 35.11%, 33.31%, and 46.32%, respectively under drought stress. This decreasing trend for fruits per plant, average fruit weight and yield per plant was also reported by Sivakumar et al [17] Prakash et al [15] and Parveen et al [16]. The reduction in fruit yield parameters under drought stress conditions is due to reduced water content in plants that adversely affects plant growth leading to reduced plant height and number of leaves [17], reduced photosynthetic efficiency, increased flower abscission, reduced pollen fertility [20] resulting in lower yields.…”

“…The results of evaluation of 39 genotypes of tomato indicated a large variability in response to water stress, as revealed through analysis of variance showing highly significant differences among the genotypes as well as the interaction effect between the genotypes and irrigation levels for all the traits studied (Table 2). The per se performance of 39 tomato accessions revealed a decreasing tendency for plant height, stem girth and number of primary branches under drought stress as compared to irrigated conditions [14,15,16]. Average plant height was highest under control condition (78.42 cm) as compared to drought stress condition (46.66 cm).…”

Yield response factor (Ky) and initial growth in black pepper in a tropical environment

“…A water deficit, is expected to reduce dry weight since the proportion of leaves in the dry matter is reduced. According to Parveen et al (2019), water stress harms plant activity, reducing growth and dry matter accumulation considerably, since this stress can lead to a stomatic conductance decrease in the plant, which limits the photosynthetic processes.…”