Effects Of Nitrogen Reduction On Yield And Soil Chemical Properties Of The Old Strain Pruning Technology Of Tomato Intercropped With Bean

Tomato plays an important role in the cultivation in our country,and the economic benefit is obvious.However,the phenomenon of low yield,poor quality and excessive accumulation of nitrate in soil has become one of the most important bottlenecks affecting the production of greenhouse tomato in china.Under the premise of ensuring crop yield,fruit quality and farmers'income,reducing the amount of fertilizer,saving resources,protecting the environment,is the ultimate goal of the study of reducing fertilizer.The test on the basis of the existing research,including the bean monoculture,the tomato monoculture,old strain pruning technology of tomato intercropped with bean.The field experiment were conducted to study the effects of different nitrogen application rates(conventional N fertilization,conventional 1/3,conventional 1/2,and conventional 2/3)on the yield and soil chemical properties of the old strain pruning technology of tomato intercropped with bean in the plastic greenhouse.The main results are as follows:1.Effects of reducing nitrogen application rate on the yield of the old strain pruning technology of tomato intercropped with bean.Compared with the conventional nitrogen application,the yield of tomato and cowpea were not significantly decreased with the reduction of nitrogen application rate.The conventional 1/3,the yield of tomato was significantly lower than that of monoculture tomato(p<0.05).Intercropping treatments was significantly lower than the yield of the bean monoculture(p<0.05).2.Effects of reducing nitrogen application on tomato quality.Compared with the conventional nitrogen application,the soluble sugar content of tomato was the highestin conventional 1/2(p<0.05).In the conventional fertilization conditions,with little difference between the intercropping and monoculture.In conventional 1/3,the organic acid content was the highest and the sugar-acid ratio was the lowest.The conventional fertilization,interplanting tomato sugar-acid ratio was significantly higher than that of the monoculture.To sum up,when the content of urea was 1/2,the content of sugar and acidity in the fruit was higher,and the organic acid,soluble sugar and soluble solids were higher.3.The effect of-reducing nitrogen application rate on soil chemical properties were studied.Intercropping cowpea can increase the content of ammonium nitrogen and nitrate nitrogen in soil.4.Inaddition,intercropping can increase the content of available nutrients in the soil.The content of ammonium nitrogen and nitrate nitrogen and EC in soil was increased with the amount of nitrogen fertilizer,but decreased the pH in soil.Appropriate amount of nitrogen fertilizer can increase the content of available K in soil,but the available P in soil is not changed.In the late growth stage,the content of available nutrients in the soil was increased due to the weakening of plant growth.5.Effect of Nitrogen Application on dry and freash weight of plant.Monoculture processing plant dry and fresh weight were higher than that of intercropping(p<0.05).The dry and fresh weight of tomatoes and beans increased with the increase of nitrogen application rate.Compared with conventional fertilization,there was no significant difference in dry weight and fresh weight of N2 and N3 treatments.6.Effects of reducing nitrogen application on plant nutrient uptake.The nutrient content of tomato monoculture plants except total potassium was higher than Intercropped with bean(p<0.05).With the increase of nitrogen application amount,the total potassium content increased.Compared with the conventional nitrogen application,the total nitrogen and total potassium content of tomato plants treated with N1 was the lowest(p<0.05),except for N1,N2 and N3 had no significant difference.There was no significant difference in N1,N2,N3 and CK of total phosphorus content in tomato plants.To sum up,this intercropping model could significantly increase the ammonium nitrogen and nitrate nitrogen in soil.The content of ammonium nitrogen and nitrate nitrogen and EC in soil was increased with the amount of nitrogen fertilizer,but decreased the pH in soil.Appropriate amount of nitrogen fertilizer can increase the content of available K in soil.When the amount of nitrogen was 15kg/667m2,not only can reduce the amount of nitrogen fertilizer,improve the content of available potassium in soil,but also can meet the high quality and high yield of tomato,the yield of beans per mu could be increased by 776.66 kg.