Survival of Rough Lemon (Citrus jambhiri Lush.) Seeds Under in Vitro Saline Conditions.

Citrus is one of the major horticultural crops of the world and is relatively salt sensitive. Citrus industry of India is the third largest fruit industry after mango and banana.  Salt stress inhibits plant growth and reduces plant productivity due to water deficit, ionic toxicity, and nutritional imbalance resulting in considerable yield loss. The rough lemon (Citrus jambhiri Lush.) seeds were subjected to different concentrations of salt (0.1 to 0.9 % NaCl in MS media) along with control. Four replications were used to standardized the salt sensitivity of rough lemon.  In all the treatments, rough lemon seedlings leaves showed severe chlorophyll injuries and necrosis as compared to control. Significant decrease in seed germination, seedling height, internodal length, and subsequently plant weight was recorded with increasing concentration of salt. However, in contrast to the above characteristics, length of the primary roots increased proportionally with increase in salt concentration in the culture media. In comparison to the control, salt treatments resulted in increased level of Na⁺ and Cl^- ions in the seedlings and decrease of K⁺/Na⁺ratio. Tolerance index was found minimum in control.

Key words: citrus, salt, sensitivity, chlorosis, sodium, chloride