潮汐灌溉对番茄苗期生长及基质水分耗散的影响

Effects of Ebb-and-flow Irrigation on Tomato Seedling Growth and Substrate Water-dissipation

【目的】研究潮汐灌溉方式下番茄幼苗生长及根系抗氧化酶活性变化和基质水分耗散规律,为番茄潮汐灌溉育苗技术的推广应用提供科学依据。【方法】以番茄瓯秀201为试材,设置潮汐灌溉和顶部洒水灌溉2种方式,分析2种灌溉方式下番茄幼苗生长和根系生理指标的变化,拟合潮汐灌溉方式下基质水分耗散规律。【结果】潮汐灌溉方式下,穴盘质量与气温、空气相对湿度呈线性关系,相关系数分别为-0.846、0.920;穴盘质量减少量与气温、空气相对湿度呈线性关系,相关系数分别为0.966、-0.853。与顶部洒水灌溉相比,在番茄4叶1心时,潮汐灌溉下番茄根系鲜质量、干质量、根系体积、根系长度分别提高44.81%、45.91%、93.81%、9.41%;潮汐灌溉下番茄根系抗氧化酶活性显著高于顶部洒水灌溉处理,而丙二醛(MDA)含量却显著下降;潮汐灌溉下番茄幼苗的净光合速率(P_(n))和气孔导度(G_(s))均显著高于顶部洒水灌溉处理。【结论】潮汐灌溉下基质的水分吸收与耗散与气温、空气相对湿度显著相关,潮汐灌溉可显著促进番茄幼苗生长,使番茄根系保持较高生长活性,有利于番茄植株保持较高的光合能力。

【Objective】Growth and root physiology of tomato seedlings and water-dissipation of substrate under ebb-and-flow irrigation in tray cultivation were studied.【Methods】Growth and root physiology of Ouxiu 201 Tomato seedlings as well as dissipation of moisture in the substrate irrigated by either ebb-and-flow or sprinkling method were monitored in a greenhouse experimentation.【Results】Under the ebb-and-flow irrigation,the seedling tray weight correlated linearly with the greenhouse temperature at a correlation coefficient of−0.846 and with the RH at 0.920.The weight loss due to evaporation increased with rising temperature at a coefficient of 0.966 and RH at−0.853.In comparison to sprinkling,the ebb-and-flow irrigation resulted in higher fresh weight,dry weight,volume,and length of roots at 4-leaves-and-one-bud stage of the seedlings by 44.81%,45.91%,93.81%,and 9.41%,respectively,and significantly elevated antioxidant enzyme activity of the roots as well as the P_(n),and G_(s) of the plant,but significantly lower MDA content.【Conclusion】In the tray cultivation of tomato seedlings,the gain and loss of water in the substrate significantly correlated with the ambient temperature and RH under the ebb-and-flow irrigation which enhanced the seedling growth and fostered a vital root system with robust photosynthesis.