Influence of mulching and salt content of irrigation water on the performance of fruit vegetables in the arid sandy soils of Oman; I: tomato growth and yield

摘要

The growth and yield responses of four tomato cultivars with and without mulching were evaluated at five sites (S1 - S5) where salinity levels of irrigation water ranged from 0.6 to 12.7 dS/m. High salinity levels increased total soluble solids in the fruits but severely inhibited both vegetative growth and total fruit yield compared to lower salinity. Significant interaction effects on yield were noted for mulching and salinity. Mulching enhanced tomato yield under higher salinity levels. Leaf analysis of all tomato cultivars grown under high salinity stress (i.e., S1 and S2) revealed a higher concentration of Na~+ and Cl~- and a low concentration of K~+ resulting in a low K~+/Na~+ ratio, and hence, an extremely poor performance of the plants. Since all cultivars survived and produced measurable yields even at the highest salinity conditions, there is a possibility that they could produce economical yields under moderate salinity levels. Although the results in the present study indicated that economical yields of modern tomato cultivars are difficult to obtain in Oman under the S1 and S2 saline conditions, such conditions can be utilized for preliminary screening for salt tolerant cultivars from a germplasm population of high genetic variabili