Abstract:
The objective of this research was to investigate the effects of deficit irrigation on
physiological and agronomic terms of eggplant to maximize the Water Use Efficiency
(WUE) without affecting the final yield and fruit quality parameters under arid
environment. Therefore, two field experiments were conducted at two different sites:
Ghor Al-Safi, Jordan Valley and Sail Al-Karak, Karak Valley, Karak Province, Jordan,
using a common eggplant cultivar (Classic) using five irrigation levels: 20, 40, 60, 80, and
100% based on field capacity. The most stressful Deficit Irrigation (DI) treatments (40
and 20%) resulted in significant effects on leaf area, leaf relative water content, leaf water
potential and leaf mineral content. Biochemical parameters also showed an increase in
proline and a decrease in chlorophyll content under water deficit conditions. Fruit weight
and total yield decreased with DI. The control (100% irrigation treatment) plants
revealed higher nutrient contents than the water-stressed plants. The fruit TSS and
titratable acidity were increased at both sites as the irrigation regime decreased from 100
to 20%. Fruit nutrient content decreased with increasing water deficit. However, the
differences were not significant between the control (100% irrigation treatment) and the
80% irrigation treatment. The 80% treatment showed high water use efficiency with
relatively small effects on plant growth performance compared with the control. As a
result, DI level at 80% can be utilized to increase WUE without a significant effect on crop
growth performance.
Keywords: Arid and semi-arid environments, Crop quality, Deficit irrigation, Water use
efficiency, Yield
