Jojoba (Simmondsia chinesis (Link) Schneider): A potential shrub in Arabian Desert

ABSTRACT. A two-years field trial was initiated on 20/9/93 to assess the effect of eight (23) fertilizer treatments comprising two levels (zero and 50 kg ha–1) of each of the three major fertilizer elements (N, P and K) on vegetative growth of a heterogenous jojoba population established on 28/2/93. Data taken on nine morphological traits for eight consecutive seasons (Fall 1993 up to Summer 1995) revealed high significant differences among seasons for each of the studied traits. In addition, main effects of N, P and K on morphological traits were generally absent and when present (1st and 8th seasons) they were all negative, with the exception of branch length (winter 1993) that was pos-itively increased by N application. Effect of N1P0 and N0P1 on number of branches (3 out of 8 seasons), N1P1 on leaf area and leaf weight (Fall 1993) and of P0K0 and P1K1 on plant height and number of branches (Summer 1995), on the other hand, were all positive and significant. Among second or-der interactions, effects of N1P1K1 and N1P1K0 on leaf area and Specific Leave Area (SLA) (1st and 3rd seasons) were the highest, but were statistically similar to those of N0P0K0. Application of N had also significantly increased N content (fall, winter and spring) and P content (summer) of Jojoba leaves in the first year