Effect of water supply regimes on physiological parameters and productivity in eggplant grown under mediterranean climate conditions

Drought has affected agriculture and intensified water scarcity. The effect of two irrigation regimes was evaluated on 13 eggplant genotypes selected as diverging for several fruit/plant qualitative traits, yield and drought tolerance. Two commercial varieties commonly used by growers in Morocco were tested. The irrigation treatments consisted of two different conditions: (i) control irrigation (Tr-C) adopted by the grower; (ii) water shortage of 50% of the amount of this irrigation (Tr-50%). Results showed that reduced water supply significantly impacted growth and quality parameters of each genotype/variety (p < 0.001) between treatments, particularly, traits such as plant height, number of flowers and leaves. Non-significant differences between treatments were observed Fv/Fm, DI0/CS0 and ABS/CS0 ratios. In terms of relative water content (RWC), genotype C10 showed remarkable drought resilience, with only a 4.12% reduction. Water stress resulted in significant reductions in the number of fruits for C8 by 49.58% and yield per plant for the genotype B1 by 39.19%. Notably, genotypes C10 and C13 demonstrated significantly better performance compared to the other genotypes, yielding 1.48 and 1.53 kg/plant, respectively, while commercial varieties A and V produced 1.98 kg/plant and 1.86 kg/plant. These results provide valuable information for the selecting and breeding of tolerant eggplant genotypes under drought-prone environments.

干旱已对农业生产造成负面影响，并加剧了水资源短缺问题。本研究选取13个因多项果实、植株品质性状、产量及耐旱性存在显著差异的茄子基因型（genotype），旨在评估两种灌溉制度对其的影响，同时测试了摩洛哥种植者普遍使用的2个商业品种。灌溉处理设置了两种不同条件：(i) 农户常规采用的对照灌溉（Tr-C）；(ii) 该灌溉量50%的水分胁迫处理（Tr-50%）。结果表明，不同处理间的供水减少对各基因型/品种的生长及品质参数均产生了极显著影响（p < 0.001），其中株高、花数及叶数等性状受影响尤为突出。处理间的Fv/Fm、DI0/CS0及ABS/CS0比值未呈现显著差异。就相对含水量（relative water content, RWC）而言，基因型C10表现出优异的耐旱性，其相对含水量仅下降4.12%。水分胁迫使C8的果实数量显著减少49.58%，并使基因型B1的单株产量降低39.19%。值得注意的是，与其余基因型相比，C10和C13的表现显著更优，单株产量分别达1.48 kg和1.53 kg；而商业品种A和V的单株产量则分别为1.98 kg和1.86 kg。本研究结果为干旱频发环境下耐旱茄子基因型的选育提供了极具价值的参考依据。