Abstract

Aloe vera is one of the best medicine plants in the world. It requires limited irrigation depending on the capacity of the soil to retain humidity. Drought is one of the key reasons for declining production of agriculture. In this study, effect of irrigation levels and zinc sulfate on Aloe plants was studied. The irrigation treatments were: 30, 60 and 90% water depletion. Foliar zinc application includedtreatments of control, 1.5 and 3 g/1 during experiment. Results revealed that the irrigation levels and zinc sulfate affected the most morphological and chemical characteristics in A. vera. There were no significant differences between 30 and 60% treatments. Water deficit (90% WD) decreased the plant height, external leaf length, internal leaf length, leaf thickness, leaf fresh weight, leaf dry weight, chlorophyll a, chlorophyll band total chlorophyll. Also amino acid proline and chloride ion increased by severe. drought. Application of Zn enhanced the external leaf length, internal leaf length, amount of chlorophyll a, total chlorophyll and amino acid proline. Therefore, 60% water depletion was recommended for using water and obtaining the plant suitable growth. Also foliar zinc treatment had the role of plant resistance by increasing proline to drought stress.