Review on the mechanisms of the response to salinity-alkalinity stress in plants
WANG Quanzhen;LIU Qian;GAO Yani;LIU Xu;Department of Grassland Science,College of Animals Science and Technology,Northwest Agriculture and Forestry University;
Salinity-alkalinity stress( SAS) is one of the major abiotic stresses affecting the growth and development of plants and has been a severe problem that restricts crop production and even the development of the ecological environment. It is vital to understand the mechanisms behind the response to SAS in plants for effective reclamation and utilization of salinealkali soil. Plants vary in response to salt and alkali stresses,but salt stress has generally been the focus of numerous SAS studies. In addition,alkali stress is more severe than salt stress because of the accompanying high p H stress,which can inhibit uptake of ions and disrupt the ionic balance of cells. This article briefly describes the damage caused by these stresses and interprets the mechanisms in terms of the influences on biomass,photosynthesis,ion balance,and membrane permeability using a comprehensive summary of the advances in research on the physiological and biochemical responses to SAS. We focused on the alleviating mechanisms of plants under SAS with regard to selective ion absorption and p H balance,the synthesis of osmotic regulation substances,improvement of enzymatic antioxidant capacity,and the expression of genes relevant to SAS tolerance. Furthermore,this article proposes five ways to cope with SAS,including the addition of exogenous substances,synergistic effects of fungi,use of biotechnological tools,SAS acclimation,and breeding cultivars for SAS tolerance. Significant progress has been made using traditional methods to improve SAS tolerance,although genetic tools play a major role and comprise the direction of our further research as well. There is an urgent need to select SAStolerant varieties through biotechnological methods. The prospects for developing SAS tolerance are also discussed,with the aim of providing a reference for improving plant resistance to stresses and increasing crop yield. 1) Although SAS limits crop growth and reduces agricultural productivity,it may also improve the quality of some fruits. It is,therefore,important todetermine a balance between the yield and quality of plants. It is also necessary to determine the dominant factors in saltalkali tolerance. Some indices have been frequently used in past studies,and a breakthrough in new indices is required. 2)The differentially expressed proteins detected in plants have not been completely understood. The revelation of useful information related to SAS tolerance will lead to some unexpected discoveries. In the near future,it is important to increase the tolerance of plants to SAS by using genetic engineering technologies. The importance of genes in negative regulation needs to be considered. High throughput analysis of the differences in SAS tolerance between salt-tolerant plants and saltsensitive plants may aid in determining the root causes of the differences. More economic and ecological benefits can be achieved by cultivating additional SAS-tolerant plants and exploring the beneficial effect of saline-alkali tolerant plants on saline-alkali land that requires restoration and amelioration. These analyses also provided new insights into understanding the potential tolerance systems within plants.
【CateGory Index】： Q945.78
【CateGory Index】： Q945.78