Effects Of Nutrient And Light Stress On Growth And Development Of Vegetables At Seedling Stage

In recent years,unreasonable use of nutrients and haze weather have seriously affected the growth and development of facility vegetables.In order to study the influence of nutrients and light stress on the growth and development of vegetables at seedling stage,this paper conducted the research by combining data analysis and pot experiment.The effects of nitrogen stress and light stress on crop growth were quantitatively analyzed.The effects of nitrogen and light stress on crop growth were quantitatively analyzed.On the basis of data analysis,9 kinds(3 types)of vegetables were selected for pot experiment(pot experiment I),and the double control factors of nitrogen and light stress were used as treatment to study the difference of influence of nitrogen and light stress among different species.On this basis,another 11 peppers varieties(pot experiment Ⅱ)were selected to study the differences in the effects of nutrient and light stress among varieties.The main results are as follows:(1)Data analysis results showed that plant height,leaf area,net photosynthetic rate and aboveground dry weight all had positive or negative effects under nitrogen stress and light stress,which indicated that the crops had adaptability to resource stress environment and provided theoretical basis for pot experiment.(2)Nitrogen and light stress had positive or negative effects on the growth and development of 9(3 types)vegetables at seedling stage.Nitrogen stress(KNO3 0 mg/kg)had positive effects on the distribution,root system and rhizosphere soil indexes of vegetables at seedling stage,and had significant positive effects on the subsurface indexes.Light stress(6,000 lux)has a positive effect on the growth,morphology,physiology and dry matter accumulation indexes of vegetables at seedling stage,and has a significant positive effect on aboveground indexes.Proper nitrogen and light stress can improve the ability of vegetable to obtain potential resources at seedling stage.There was no significant difference among different crops among the three categories,indicating that there was no significant difference in the adaptability of the three categories of vegetables to the stress of resources and environment at the seedling stage.However,among the 9 vegetables,the aboveground and underground parts of peppers showed strong adaptability to the stress of resources and environment to nitrogen and light.(3)Nutrient and light stress had positive or negative effects on the growth and development of 11 kinds of peppers at seedling stage.Nutrient stress(KNO3,KH2PO4,K2SO4,0 mg/kg)had positive effects on dry matter accumulation,distribution,root system and rhizosphere soil indexes of peppers at seedling stage,and had significant positive effects on underground indexes.Light stress(6,000 lux)significantly affects the growth,morphology,physiology and dry matter accumulation of peppers at seedling stage,and positively affects the aboveground index significantly.Proper nutrient and light stress can improve the ability to obtain potential resources.There was no significant difference among different cultivars of the same crop,indicating that there was no significant difference in the adaptability of different cultivars to resource stress environment at seedling stage.In summary,proper control of nutrients and light of the tested vegetables at seedling stage can improve the ability to obtain potential resources,reduce resource waste,and improve the utilization rate of nutrients and light.Under light stress,the yield of leaf vegetables with short growth period was less affected.The shortage of nutrients and light will lead to the significant decrease of dry matter on the ground,the increase of plant height and leaf area,and the poor growth at the seedling stage.In case of haze weather,should be appropriate to supplement the light.