The Effect Of Different Water And Soil Nitrogen Interaction On Physiological And Biochemical Characteristics And Water Use Efficiency Of Broccoli

Selected You Xiu broccoli as cultivars material and studied the effects of differentwater and soil nitrogen interaction on growth, quality, photosynthetic characteristics, yield,water use efficiency of broccoli, which can afford a theoretical basis for the establishment ofthe irrigation and nutrition system of broccoli culture. The main results as follows:1. In this experiment, broccoli growth has a distinctly affected by different water and soilnitrogen interaction, water and nitrogen too much or too little can cause inhibition to thegrowth. Under W2treatment, the plants grow healthy, leaf area index were significantlygreater than other treatment. W2N1treatment of growth and dry mass was significantlygreater than other treatment, expressed that the process is beneficial to the growth of plants.2. Quality of broccoli, including nitrate, Vitamin C, soluble sugar, and protein content，isaffected mostly by nitrogen, which content of nitrate and protein in ball-flower increasedalong with nitrogen supply levels rising. With shortness and excessiveness of nitrogensupply would reduce significantly the quality, but not directly affected by water supply. Withthe highest content of soluble sugar, Vitamin C, protein, and lower content of nitrate. W2N1treatment is to achieve the optimal quality of water and nitrogen management patterns. Inconclusion, in order to improve the quality of broccoli, not only to consider the personalityfactors of vegetables themselves, but also should pay attention to scientific water andnitrogen management.3. The interaction of different water and nitrogen has significant effect on photosynthesis ofbroccoli. In W2N1treatment, broccoli net photosynthetic rate（Pn）, transpiration rate（Tr）and stomata conductance（Gs） was the highest, while cell CO₂concentration（Ci） was thelowest．Therefore, the W3N3treatment, Fv／Fm was the highest, others like ФPSII, qP,NPQ were the W2N1highest. So we have the conclusion was that, nitrogen applicationcould enhance the Pn, Tr, Gs, ФPSII, qP and NPQ, and decrease intracellular concentrationof CO₂. The results indicated that nitrogen application could improve the opening proportionof photosynthetic instruments, photos-catching ability and electronic transport rate，and thenamended the efficiency of photosynthetic instruments；The effects of water application directimpacted Pn, Gs and Fv／Fm. Comprehensive the above indicators, processing W2N1leaf photosynthetic ability is strong, and75%of irrigation and the local nutrition combination fora better model.4. The interaction of different water and nitrogen has significant effects on nutrientabsorption and physical and chemical properties of soil. Under the interaction of water andnitrogen, total and available N in soil were increased with nitrogen applicationincreased．Appropriate irrigation application benefited the accumulation of total andavailable N in soil．More P and K were accumulated in broccoli plants with appropriate Nsupplied, and high irrigation under low nitrogen can reduce the available P and available Kcontent. Parts of broccoli plant for total N absorption and accumulation was influenced bynitrogen fertilizer amount and irrigation interaction. The experimental results also showedthat different water and nutrition interaction had no significant effect on soil pH, but hassignificant effects on soil EC. Through multi-objective evaluation concluded that the W2N1and W1N2treatment were relatively appropriate, promoted the plant nutrient uptake andreduced the pollution to the environment.5. Two factors of irrigation and nutrition on the plateau summer broccoli has a significanteffect on yield. The results show that the increasing amount of water and nitrogen canobviously increase the yield and water use efficiency of broccoli, but over a certain rangecan lead to decline. In conclusion, the yield and water use efficiency of W2N1processingperformance as the highest, and than the lowest yield treatment increased by36.30%.All above, this experiment treatment W2N1--nitrogen application was414kg·hm-2,water irrigation was1253m3·hm-2for applying the best processing, which suited fertilizationand water saving management mode, better quality, high yield and fertilization applicationscheme, for actual reasonable cultivation and scientific management to provides the basis intheory and in practice for broccoli.