Drought stress negatively impacts growth and physiological processes in plants.The foliar application of glycine betaine(GB)is an effective and low-cost approach to improve the drought tolerance of trees.This study ex...Drought stress negatively impacts growth and physiological processes in plants.The foliar application of glycine betaine(GB)is an effective and low-cost approach to improve the drought tolerance of trees.This study examined the effect of exogenously applied GB on the cell membrane permeability,osmotic adjustment,and antioxidant enzyme activities of Phoebe hunanensis Hand.-Mazz under drought stress.Two levels(0 and 800 mL)of water irrigation were tested under different applied GB concentrations(0,50,100,and 200 mM).Drought stress decreased the relative water content by 58.5%while increased the electric conductivity,malondialdehyde,proline,soluble proteins,soluble sugars,and antioxidant enzyme activities(superoxide dismutase,catalase,peroxidase)by up to 62.9%,42.4%,87.0%,19.1%,60.5%,68.3%,71.7%,and 83.8%,respectively,on the 25^(th) day.The foliar application of GB,especially at 100 mM,increased the relative water content of P.hunanensis leaves under drought stress.The concentration of GB from 50 to 100 mM effectively alleviated the improvement of cell membrane permeability and inhibited the accumulation of membrane lipid peroxidation products.Under drought stress,the concentrations of proline,soluble proteins,and soluble sugars in the leaves of P.hunanensis increased as the applied GB concentration was increased and the water stress time was prolonged.Exogenously applied GB decreased oxidative stress and improved antioxidant enzyme activities as compared with treatments without GB application.Furthermore,the physiological and biochemical indexes of P.hunanensis showed a certain dose effect on exogenous GB concentration.These results suggest that GB helps maintain the drought tolerance of P.hunanensis.展开更多
【目的】白蚁具有降解木质纤维素的能力,主要场所在消化道内,因此消化道形态结构的研究具有重要意义。【方法】本文对采自河南省的3种白蚁(平额散白蚁Reticulitermes planifrons Li et Ping、湖南散白蚁Reticulitermes hunanensis Tsai ...【目的】白蚁具有降解木质纤维素的能力,主要场所在消化道内,因此消化道形态结构的研究具有重要意义。【方法】本文对采自河南省的3种白蚁(平额散白蚁Reticulitermes planifrons Li et Ping、湖南散白蚁Reticulitermes hunanensis Tsai et Peng和双工土白蚁Odontotermes dimorphus Li et Xiao的兵蚁和工蚁头胸部特征及其消化道结构进行了比较。【结果】两种散白蚁兵蚁的头壳、后颏和上颚没有明显差异,但与双工土白蚁差异显著。3种白蚁工蚁的前肠、后肠及消化道平均长度均大于兵蚁,且差异显著(P<0.05),而中肠的差异不显著;双工土白蚁的肠道总长度工蚁/兵蚁比值(1.4倍)大于两种散白蚁(1.1倍);除了嗉囊和囊形胃外,两种散白蚁工蚁的其余消化道各段差异显著(P<0.05),与双工土白蚁相比差异也显著。【结论】工蚁的消化道比兵蚁发达,散白蚁的消化道结构与土白蚁有较大不同,这些结果与工蚁和兵蚁的社会分工有关,同时也表明高等白蚁与低等白蚁相比不仅是采食习惯的差别,自身消化系统结构与分区也有较大不同,并为白蚁的生物防治和生物质资源利用提供了资料。展开更多
基金This work was supported by the Science and Technology Research Project of Hubei Provincial Department of Education(Q20191309)the Engineering Research Center of Ecology and Agricultural Use of Wetland(Ministry of Education,KF2018113)Shuangzhu Forest Farm in Zhuxi County(2020H21003).
文摘Drought stress negatively impacts growth and physiological processes in plants.The foliar application of glycine betaine(GB)is an effective and low-cost approach to improve the drought tolerance of trees.This study examined the effect of exogenously applied GB on the cell membrane permeability,osmotic adjustment,and antioxidant enzyme activities of Phoebe hunanensis Hand.-Mazz under drought stress.Two levels(0 and 800 mL)of water irrigation were tested under different applied GB concentrations(0,50,100,and 200 mM).Drought stress decreased the relative water content by 58.5%while increased the electric conductivity,malondialdehyde,proline,soluble proteins,soluble sugars,and antioxidant enzyme activities(superoxide dismutase,catalase,peroxidase)by up to 62.9%,42.4%,87.0%,19.1%,60.5%,68.3%,71.7%,and 83.8%,respectively,on the 25^(th) day.The foliar application of GB,especially at 100 mM,increased the relative water content of P.hunanensis leaves under drought stress.The concentration of GB from 50 to 100 mM effectively alleviated the improvement of cell membrane permeability and inhibited the accumulation of membrane lipid peroxidation products.Under drought stress,the concentrations of proline,soluble proteins,and soluble sugars in the leaves of P.hunanensis increased as the applied GB concentration was increased and the water stress time was prolonged.Exogenously applied GB decreased oxidative stress and improved antioxidant enzyme activities as compared with treatments without GB application.Furthermore,the physiological and biochemical indexes of P.hunanensis showed a certain dose effect on exogenous GB concentration.These results suggest that GB helps maintain the drought tolerance of P.hunanensis.
文摘【目的】白蚁具有降解木质纤维素的能力,主要场所在消化道内,因此消化道形态结构的研究具有重要意义。【方法】本文对采自河南省的3种白蚁(平额散白蚁Reticulitermes planifrons Li et Ping、湖南散白蚁Reticulitermes hunanensis Tsai et Peng和双工土白蚁Odontotermes dimorphus Li et Xiao的兵蚁和工蚁头胸部特征及其消化道结构进行了比较。【结果】两种散白蚁兵蚁的头壳、后颏和上颚没有明显差异,但与双工土白蚁差异显著。3种白蚁工蚁的前肠、后肠及消化道平均长度均大于兵蚁,且差异显著(P<0.05),而中肠的差异不显著;双工土白蚁的肠道总长度工蚁/兵蚁比值(1.4倍)大于两种散白蚁(1.1倍);除了嗉囊和囊形胃外,两种散白蚁工蚁的其余消化道各段差异显著(P<0.05),与双工土白蚁相比差异也显著。【结论】工蚁的消化道比兵蚁发达,散白蚁的消化道结构与土白蚁有较大不同,这些结果与工蚁和兵蚁的社会分工有关,同时也表明高等白蚁与低等白蚁相比不仅是采食习惯的差别,自身消化系统结构与分区也有较大不同,并为白蚁的生物防治和生物质资源利用提供了资料。
