Effects Of Mycorrhizal Seedling Substrates On Nutrient Uptake And Salt Tolerance Of Processing Tomato

In order to find out the effect of mycorrhizal medium on the growth and physiological characteristics of Processing Tomato under salt stress,Tunhe 5501 was used as the experimental material,which was cultivated in mycorrhizal and non mycorrhizal medium,then transplanted to mild,moderate and severe salinized soil for pot experiment.The effects of mycorrhizal media on soil nutrients,plant growth,photosynthesis and other parameters were studied during the seedling,flowering,fruit setting,fruit expanding and harvest stages of processing tomato:(1)Soil salt and nutrient:the salt content of mycorrhizal seedling treatment was lower than that of non mycorrhizal seedling treatment in different concentrations of salinized soil,and there was significant difference between mild and moderate salinized soil from flowering stage to fruit setting stage,which decreased by 7.2%,9.9%,11.3%and 22.5%respectively.The contents of organic matter,nitrogen,phosphorus and potassium in each treatment of mild salinized soil were 14.4%,102.2%,40.4%and 43.1%lower than that of severe salinized soil,respectively,which showed that mycorrhizal treatment was lower than that of non mycorrhizal treatment,and decreased with the increase of growth period,and the change of mycelial density was consistent with the nutrient content.(2)Root parameters and mycorrhizal infection rate:mycorrhizal seedling treatment can improve the total root length,root surface area and specific root length of processing tomato in different salinized soil concentrations,with the highest increase of 57.0%,135.5%and 14.43%.In light,medium and heavy salinized soil,the ratio of root to shoot,mycorrhizal infection rate and mycorrhizal dependence decreased with the increase of soil salt concentration,and mycorrhizal treatment was higher than non mycorrhizal treatment.With the development of growth period,the ratio of root to shoot,mycorrhizal infection rate and mycorrhizal dependence all increased first and then decreased,and showed the maximum value in flowering or fruiting period respectively.(4)Nutrients in the ground and underground:under salt stress,the contents of N,P and K in the plant decreased,and K+/Na+ decreased.Mycorrhizal seedling could alleviate the inhibition of different concentrations of salt stress on the growth of processing tomato,and the content of N in the plant increased by 5.2%-11.9%.P content increased by 1.6%-74.0%from seedling stage to fruit expansion stage.Compared with the non mycorrhizal treatment,the K content of mycorrhizal treatment increased by 10.3 g/kg.In the three salinized soils,the yield and quality of processing tomato were higher in mycorrhizal treatment than in non mycorrhizal treatment.In the three salinized soils,the yield increased by 11.8%,14.5%and 13.3%respectively,and the content of soluble sugar and protein increased by 3.4%-15.6%.To sum up:mycorrhizal seedling medium can alleviate the persecution of salt stress on the growth of processing tomato,improve the soil rhizosphere microenvironment,promote leaf photosynthesis,promote the plant to absorb nutrients,optimize the ion absorption and distribution,increase the quality of dry matter,and ultimately improve the yield and quality of processing tomato,Therefore,it can provide certain application value for the sustainable development of processing tomato planting in the salinized soil of arid area.