Effects Of Brassinolide (BR) And Exogenous Calcium On Growth And Yield Of Facility Tomato

In recent years,in order to meet consumer demand,off-season vegetable cultivation area is increasing,so that the facility tomato cultivation has been unprecedented development,and has become one of the main vegetable crops in facility cultivation in China.However,due to the single structure of facilities,improper management,high temperature and high humidity in autumn,low temperature and low light in winter,adverse climate disasters and other stresses,the plants is prone to infection and disease,which has a great impact on the growth and development of plants,and seriously hinders the yield and income of tomato in facilities.A large number of studies have shown that Brassinolide（BR）and exogenous calcium can promote plant growth and increase yield by improving disease resistance and stress resistance of tomato plants.However,previous studies on the functions of the two were mostly focused on pot experiment,there is less research on the application of facilities,and the research report on the combined application of the two was less.Therefore,in order to test the application effect of BR and its combined application of exogenous calcium,this study explored the effects of different concentrations of different concentrations of BR and exogenous calcium on the growth,bear fruit,and yield through field of greenhouse tomatoes through the facility tomato test.In order to provide theoretical basis for high-quality cultivation of tomato.The results are as follows:1.Effects of different concentrations of BR and combined application of exogenous calcium on growth,physiology,disease and yield of autumn tomato in greenhouse:BR treatment could increase the plant height,stem diameter and leaf number of tomato,and 0.5mg/L BR treatment had a significant effect.High concentration BR inhibited fruit-setting rate of tomato and reduced yield.However,suitable concentration BR increased the yield by increasing the fruit-setting rate.Suitable BR treatment could significantly increase leaf chlorophyll content,increase net photosynthetic rate and stomatal conductance,but high BR treatment seemed to inhibit the photosynthetic process.Appropriate concentration of BR could reducing the content of malondialdehyde（MDA）and relative conductivity,increasing the content of proline（Pro）and soluble sugar.BR treatment reduced the incidence and disease index of tomato TY virus disease.BR combined with exogenous calcium could increase the yield by increasing chlorophyll content,photosynthesis,Pro and soluble sugar content,and disease resistance of the plant.In conclusion,0.5 mg/L BR treatment and its combined application with exogenous calcium can be applied to the cultivation of autumn tomato in greenhouse and control TY virus disease.2.Effects of different concentrations of BR and combined application of exogenous calcium on growth,physiological characteristics,fruit setting and yield of overwintering tomato in Solar Greenhouse:High concentration of BR inhibited the growth of tomato plant height in early stage.The plant height was increased by proper concentration of BR.High concentration BR significantly increased MDA content and decreased soluble sugar content in tomato leaves.The appropriate concentration of BR treatment alleviated the increase of MDA content in leaves and reduced the relative electrical conductivity,meanwhile,the Pro and soluble sugar contents in tomato leaves were increased,and the chlorophyll content of tomato was increased.High concentration of BR or low concentration of BR inhibited fruit setting and reduced the yield of the first inflorescence of tomato.Appropriate concentration of BR treatment promoted fruit enlargement and increased tomato yield.BR combined with exogenous calcium treatment significantly increased the number of tomato leaves,increased the photosynthetic area and accelerated the photosynthetic process by increasing chlorophyll content,and then promoted fruit enlargement and fruit yield significantly.3.Effects of BR and exogenous calcium on the growth of tomato seedlings in pot greenhouse:Spraying BR promoted the growth of tomato seedlings,increased biomass accumulation and chlorophyll content,and improved root activity,and each index increased first and then decreased with the increase of BR concentration.0.1 mg/L BR treatment had the most obvious effect.Spraying BR reduced the relative electrical conductivity of seedling leaves,but there was a significant difference between BR and CK1 at low concentration.In addition,although BR combined with exogenous calcium had no significant effect on the growth of plant height and stem diameter,the chlorophyll content,biomass accumulation and root development of tomato seedlings were higher than that of BR or 0.2%CaCl₂alone.