Malejane Dunsfort N, Tinyani Peter, Soundy Puffy, Sultanbawa Yasmina, Sivakumar Dharini
Phytochemical Food Network Research Group Department of Crop Sciences Tshwane University of Technology Pretoria South Africa.
Centre for Food Science and nutrition Queensland Alliance for Agriculture and Food Innovation (QAAFI) The University of Queensland Coopers Plains QLD 4108 Australia.
Food Sci Nutr. 2017 Dec 6;6(2):334-341. doi: 10.1002/fsn3.559. eCollection 2018 Mar.
This study investigated the effect of deficit irrigation at three management allowable depletion levels (MAD) 25%, 50%, and 75% on phytochemicals, ascorbic acid, antioxidant activity, glucose, fructose, and fresh and dry mass in two green leafy lettuce cultivars (Lollo Bionda and Vera) at harvest. Genotype response was observed during deficit irrigation on fresh and dry mass at harvest. Vera revealed similar fresh mass at MAD levels 25% and 50%. Chicoric acid, caftaric acid, and chlorogenic and caffeic acid tended to increase at 50% MAD, while kaempferol, quercetin, and myricetin increased at 75% MAD in both cultivars indicating increasing antioxidant properties. Ascorbic acid content declined with increasing MAD levels and no definite trend on β-carotene content was noted in these cultivars with respect to MAD irrigation. Deficit irrigation at 50% and 70% increased glucose concentration in cv. Lollo Bionda. Deficit irrigation influences the abiotic stress condition that stimulates the biosynthesis of phytochemicals in plants and improves crop quality. However, deficit irrigation can affect marketable crop yield. Based on findings of this study, the lettuce cv. Vera can be recommended as a suitable cultivar for deficit irrigation (at MAD 50% levels) for improving dietary phytochemicals and crop quality without compromising fresh mass for marketing.
本研究调查了在三种管理允许亏缺水平（MAD），即25%、50%和75%下进行亏缺灌溉，对两个绿叶生菜品种（罗勒比昂达和维拉）收获时的植物化学物质、抗坏血酸、抗氧化活性、葡萄糖、果糖以及鲜重和干重的影响。在亏缺灌溉期间观察到了收获时基因型对鲜重和干重的响应。维拉在MAD水平为25%和50%时鲜重相似。在两个品种中，二咖啡酰奎宁酸、咖啡酰奎宁酸以及绿原酸和咖啡酸在MAD为50%时趋于增加，而山奈酚、槲皮素和杨梅素在MAD为75%时增加，表明抗氧化特性增强。抗坏血酸含量随MAD水平的增加而下降，并且在这些品种中，关于MAD灌溉，未观察到β-胡萝卜素含量有明确趋势。在罗勒比昂达品种中，50%和70%的亏缺灌溉增加了葡萄糖浓度。亏缺灌溉影响非生物胁迫条件，刺激植物中植物化学物质的生物合成并提高作物品质。然而，亏缺灌溉会影响适销作物产量。基于本研究的结果，生菜品种维拉可被推荐为亏缺灌溉（MAD为50%水平）的合适品种，以提高膳食植物化学物质和作物品质，同时不影响用于销售的鲜重。
