水冷苗床对番茄幼苗生理的影响

 为探明水冷苗床促进番茄幼苗健壮生长的机理，以‘粉都77’番茄为材料，调查了水冷苗床和常规苗床下番茄幼苗根系形态、养分吸收及生理生化指标。结果表明：水冷苗床提高了幼苗根系的吸收面积、根系活力（茎流速率和根系呼吸速率）和养分吸收能力。水冷苗床番茄幼苗地上部N、Ca 和Mg 含量显著高于对照，而根系P、Ca 和Mg 含量显著低于对照。根际降温措施不仅提高了番茄幼苗根系抗氧化能力，也显著提高了幼苗的抗氧化能力。水冷苗床作为一种新的根际降温方式，可以缓解夏季高气温对番茄幼苗生长的不利影响。

Effects of Root-zone Cooling Bed with Cold Water on the PhysiologicalMechanism of Tomato Seedling

In order to explore the physiological and biochemical mechanism of tomato seedlinggrowth promoted by root-zone cooling，tomato（Solanum lycopersicum）seedlings were cultivated incooling bed and non-cooling bed as control. Plant root morphological traits，nutrient uptake andphysiological characteristics of tomato seedlings were tested. The results showed as follows：Root surfacearea，root activity（sap flow velocity and root respiration rate）and nutrient uptake of tomato seedlings wereimproved significantly. Compared with the control bed treatment，shoot N，Ca and Mg contents of tomatoseedling in cooling bed were significantly higher，but root P，Ca and Mg contents were lower. Antioxidantability both in root and leaf of tomato seedling were promoted by root-zone cooling. This study indicatedthat root-zone cooling by cooling bed with cold water could alleviate high air temperature injury forintensive seedling production in summer.