ساسان راستگو

Citrus trees, of the most important fruit crops of arid and semi-arid sub-tropics, are subjected to several abiotic stresses including salinity, which reduces growth and crop production in majority of them considerably. The present study was carried out with the objective of investigating salinity effect on growth of lime seedlings and the role of putrescine in reducing its damage. Salinity was applied through irrigation water containing 15, 30 and 60 mili mols of sodium chloride, along with the control, and putrescine (Put) at 0, 1 and 2 mM either by foliar spraying or by adding to soil. Salinity at 30 and 60 mM decreased seedling height, new growth length, shoot fresh weight and root dry weight, and from 15 mM number of new shoots compared to the control. Effect of Put individually was significant only for number of new shoots. There was no significant effect for method of Put application. Interaction effect of Put concentration with its method of application was meaningful in terms of root fresh and dry weight. In general, the salinity equivalent to and above 4 ds m-1 electrical conductivity caused significant decrease in seedling growth of this species and Put at the concentrations used here exhibited partial effectiveness in reducing detrimental effects of salinity.