Effects Of Net-wind And Wind-sand Flow On Physiology And Photosynthesis Of Lycium Ruthenicum Murr

Sandstorm damage is a serious natural disaster that can cause plants to dwarf and even die.Therefore,the types and distribution of plants in areas with severe sand damage are limited.At present,studies on wind sand flow have been carried out on Pinus sylvestnis var.mongolica,Zea mays,Calligonum mongolicun and other plants,and important results have been achieved.Lycium ruthenicum Murr is a kind of thorny shrub of Lycium in Solanaceae.It has strong adaptability and can survive in saline alkali land,arid desert area and high temperature area.However,there have been few reports on how Lycium ruthenicum adapts to the stress environment under the stress of net-wind and wind-sand flow.In this study,6 m/s,9 m/s,12 m/s,15 m/s,and 12 m/s wind speeds were applied for 10 min,20 min,and 30 min to net-wind and wind-sand flow of Lycium ruthenicum.In flow stress studies,Lycium ruthenicum was not used as a control(CK).The relative water content,water potential,malondialdehyde content,relative conductivity,antioxidant enzymes,osmotic adjustment substances and photosynthetic physiology,chlorophyll fluorescence parameters,the stomata changes the law,and explores the adaptation mechanism of Lycium ruthenicum to the wind and sand.The research results are as follows:1.Under the treatment of net-wind and wind-sand flow,there was no obvious water loss from Lycium ruthenicum.Different wind speed stress did not cause the change of water potential.Under different time stress,the water potential of net-wind treatment decreased and the water potential of wind-sand flow treatment increased significantly.Membrane permeability showed an increasing trend,but increased stress wind speed caused less lipid peroxidation of Lycium ruthenicum,and prolonged stress caused obvious lipid peroxidation.2.Under the treatment of net-wind and wind-sand flow,the antioxidant enzyme activity is slightly different in the sensitivity to stress.SOD activity increased significantly at 6 m/s wind speed stress or 12 m/s wind speed stress for 10 min.The POD activity increased at 12 m/s wind-sand flow,15 m/s net-wind,or 12 m/s wind speed stress for 10 min.The CAT activity increased significantly at 12 m/s net-wind stress for 20 min and wind-sand flow stress for 10 min.Overall,SOD activity is more sensitive to stress,POD activity and CAT activity are more insensitive to stress,and stress enzyme activity is higher in a short time,and the protective effect is stronger.3.Under the treatment of net-wind and wind-sand flow,with the increase of wind speed or the prolongation of stress time,the content of proline increased first and then decreased.The content of proline was highest at 20 min under 12 m/s stress and the effect of osmotic adjustment was the largest.Under net-wind stress,the soluble sugar content decreased,and the soluble protein content decreased or had no obvious changes,which played a small role in osmotic adjustment;under wind-sand stress,the soluble sugar content first increased and then decreased,12 m/s stress for 20 min has the highest soluble sugar content and the largest osmotic adjustment effect,the change of soluble protein content is consistent with the net-wind treatment.4.Under the treatment of net-wind and wind-sand flow,with the increase of wind speed,the photosynthesis of Lycium ruthenicum first increased,until the 12 m/s net-wind and 9 m/s wind-sand flow stress photosynthesis reached the maximum,and then the photosynthesis began to weaken.The photosystem(PSII)of Lycium ruthenicum is unresponsive to changes in wind speed;with the prolongation of the stress time,the photosynthesis of Lycium ruthenicum gradually increased,and the photosynthesis reached the maximum after 30 minutes of stress.Compared with the net-wind stress,wind-sand flow stress photosynthesis has a smaller increase,and the photosystem(PSII)of Lycium ruthenicum is more sensitive to changes in time,resulting in photo-inhibition.The treatment of heat dissipation at different wind speeds and different times does not play a protective role.5.Stomatal factors and non-stomatal factors affect the opening and closing of the leaf stomata of Lycium ruthenicum,which in turn affects the photosynthesis of Lycium ruthenicum.Under different wind speed stress,non-stomata factors play a greater role in regulation;under different time stress,stomatal factors play a significant role in regulation.To sum up,Lycium ruthenicum has certain adaptability to net-wind and wind-sand stress,but under strong wind,Lycium ruthenicum will not be able to carry out normal physiological activities and photosynthesis.It is suggested that Lycium ruthenicum should be used reasonably in the future sandstorm control.Planting Lycium ruthenicum in the desert area with weak sandstorm(6 m/s)and moderate harm(9 m/s)can achieve better ecological benefits and economy benefit.