磁化水对不同土壤水分下黄瓜幼苗生长、光合和养分吸收的影响

采用二因素二水平完全试验设计，研究了砂培条件下磁化处理（分别为0.3T磁场强度处理的磁化蒸馏水和蒸馏水处理）对不同土壤水分条件下（正常水分处理：田间持水量的80%~85%；干旱处理：田间持水量的40%~45%，于黄瓜4~5叶期维持7 d）黄瓜幼苗生长、水分关系、光合作用和养分吸收的影响。结果表明，磁化水浇灌显著降低黄瓜幼苗的生长和水分利用，其中茎粗、地上部生物量、根生物量、总生物量、根体积、根表面积、整株耗水量和整株水分利用效率分别降低6.7%、8.9%、19.1%、9.9%、22.1%、18.5%、6.2%和10.9%；磁化水浇灌导致黄瓜幼苗叶SPAD值降低了3.7%，叶气孔导度和蒸腾速率则分别增加了21.8%和17.5%，叶瞬时水分利用效率降低了17.7%，但对净光合速率影响不大；磁化水浇灌使PSII最大光化学效率和电子传递速率分别降低了5.2%和18.6%，同时增加叶片中K含量。除叶片K含量外，干旱条件下磁化水对黄瓜生长和生理代谢影响不大，表明磁化水的作用依赖于土壤水分条件。

Effects of magnetized water on growth, photosynthesis and nutrient uptake of cucumber seedlings under different soil moisture contents

A two\|factor and two\|level complete experimental design was adopted to study the effect of magnetization treatment (magnetized distilled water with 0.3T magnetic field intensity and distilled water) on the growth, water relation, photosynthesis, and nutrient uptake of cucumber seedlings under different soil moisture contents (normal water treatment: soil moisture at 80%~85% of field water holding capacity; drought treatment: soil moisture at 40%~45% of field water capacity, and maintained at this level for 7 days at the 4~5 leaf stage of cucumber) under sand culture condition. The results showed that magnetized water application significantly decreased stem diameter, aboveground biomass, root biomass, total biomass, root volume, and root surface area of cucumber seedlings by 6.7%, 8.9%, 19.1%, 9.9%, 22.1%, and 18.5%, respectively, and whole\|plant water consumption and water use efficiency of cucumber seedlings by 6.2% and 10.9%, respectively. Magnetized water treatment reduced leaf SPAD value of cucumber seedling by 3.7%, increased leaf stomatal conductance and transpiration rate by 21.8% and 17.5%, respectively, and decreased instantaneous water use efficiency of the leaves by 17.7%, but had little effect on the net photosynthetic rate. Magnetized water treatment resulted in 5.2% reduction in the maximum photochemical efficiency and 18.6% decrease in PSII electron transfer rate. Magnetized water treatment increased the K content in the leaves. Although magnetized water treatment significantly increased the K content in the leaves of cucumber seedlings under drought stress, but had little effect on most plant growth and physiological parameters. The results suggested that the application of magnetized water on cucumber seedlings was dependent on soil moisture conditions.