Effect of Different pH-regulating Acids on Root Morphology and Yield of Lettuce in Floating Transplant System

不同酸调节溶液pH对生菜漂浮幼苗根系形态及产量的影响(英文)

[Objective] The aim was to investigate different effects of two pH-regulating acids on the root morphology and other physiological growth of Lactuca sativa L.in floating plug transplant system.[Method] HNO3 and H2SO4 were used to adjust pH condition of various nutrient concentrations in lettuce floating transplant system,the effect of two acid treatments on root traits of lettuce were investigated.[Result] These two acids made different effects on root system under a series of nutrient gradients.Under HNO3 treatment,the fresh weight of shoot and root were increased with growth of nutrient concentration;root preformed best when EC was 1.0 μs/cm.Under H2SO4 treatment,when EC was 0.8 μs/cm,the total root length and root surface area,projected area,root volume of lettuce were 344.8 cm,40.9 cm2,13.0 cm2,0.4 m3,respectively,which were significantly higher than those in HNO3 treatment.Compared the influences of acid treatments under same nutrient concentration,the result showed that H2SO4 treatment increased root/shoot ratio and all other root morphological characteristics;however,HNO3 treatment promoted the growth of shoot and lateral root,increased transplanting efficiency and facilitated realizing high yield after transplanted into open-field.[Conclusion] This study will provide theoretical reference for improving plug transplant technology of lettuce.

[目的]为了解在蔬菜漂浮育苗系统中,采用不同酸调节溶液pH是否会对蔬菜根系及其它生长指标产生不同影响。[方法]分别采用硝酸和硫酸调节生菜(Lactuca sativa)漂浮育苗系统中不同营养液浓度下的溶液pH,观察两种酸对生菜根系形态的影响。[结果]不同营养液浓度下,两种酸对根系的影响效果不同。硝酸处理下,随着营养液浓度的增加,生菜地上部、根部生物量都增加,当营养液EC达到1.0μs/cm时,生菜地上部、根部鲜重显著高于硫酸处理;硫酸处理下,当营养液EC达到0.8μs/cm时,生菜的总根长达到344.8 cm,根总表面积为40.9 cm2,投影面积为13.0 cm2,根体积为0.4 m3,显著高于硝酸处理下的相应根系形态指标。比较同一营养液浓度下两种酸的处理效果发现,硫酸处理增加生菜根冠比,促进总根长、根表面积等根系形态的生长;硝酸处理促进生菜地上部生长、促进侧根发育、提高移苗效率、移苗后利于实现高产。[结论]该研究为生菜等蔬菜漂浮育苗和集约化穴盘育苗营养调控技术奠定理论基础。