Effect of Salicylic Acid on Morpho-agronomical Traits of Guar (Cyamopsis tetragonoloba L.) under Drought Stress

Guar is a tropical, salt and drought tolerant plant. To assess the effect of salicylic acid on its morphological and agronomical traits under different irrigation intervals, a split plot experiment based on randomized complete block design with four replicates was performed in Galeh-Gang region in Kerman province, Iran. Three different irrigations with 6, 9 and 12 day intervals, assigned to main plots and four salicylic acid concentrations (0, 0.5, 1 and 2 mM) to sub plots. Salicylic acid spraying was done three times at five leaf, flowering and podding stages. The results indicated that most of the morphologic and agronomic characters of guar were influenced under different irrigation intervals. Leaf area index, number of pods per plants and number of seeds per pod were decreased when drought stress occured. Spraying plants with salicylic acid increased almost all characters under study. While, the highest number of pods per plant, seeds per pod were obtained at 2 mM and leaf area index at 1 mM salicylic acid treatments. Irrigation interval by salicylic acid interaction was significant for specific leaf area, 1000 seed weight, seed protein content and seed yield. The highest seed yield (1245.25 kg.ha-1) was belonged to the irrigation of 6 day interval and 1 mM acid salicylic treatment. As a whole it can be concluded that use of 1 mM salicylic acid treatment might increase drought tolerance of guar and prevent yield reduction during drought stress.