Abstract: In order to study the effect of coupling water and fertilizer on the root morphology and yield of summer maize, using the "3414" optimal regression design scheme, the changes of root morphology and yield components of each treatment were analyzed, and the correlation analysis of yield and the prediction of model construction. The results showed that the total root length, total root surface area and total root volume of W₃N₂C₂ were the largest, which were 2.89, 2.41 and 2.68 times than that of W₀N₀C₀.The number of ear rows, row grains, ear length, 100-seed weight of W₃N₂C₂ were 1.31, 1.19, 1.22, 1.62 times of W₀N₀C₀.The correlation between yield factors and yield was significant. The biggest influence on maize yield was the amount of irrigation, the next was the amount of carbon and the minimum was amount of nitrogen.W₃N₂C₂ increased the output of W₀N₀C₀ by 72.39%.When nitrogen and organic fertilizer were at N₂ and C₂ level, irrigation could increase maize yield by 19.78%-48.46%. When irrigation amount and organic manure were at W₂ and C₂ level, nitrogen application could increase maize yield by 6.59%-15.68%. When irrigation amount and nitrogen fertilizer were at W₂ and N₂ level, applying organic fertilizer could increase yield of maize by 4.99%-9.67%. Under low water conditions, increasing organic manure and nitrogen fertilizer could enhance soil water holding capacity and water and nutrient utilization rate, so as to reduce water and fertilizer waste and improve maize yield. The research showed that the proper proportion of water and fertilizer under the condition of water shortage played an important role in improving crop yield. In the design range of the experiment, the yield equation was Y=6 723.94+1 589.98X₁+470.79X₂+182.50X₃-194.23X₁²-74.70X₂²-78.66X₃²+42.12X₁X₂+98.28X₁X₃+89.39X₂X₃, the relative water content was 70%, the amount of nitrogen applied was 225 kg/ha, the amount of carbon was 2 700 kg/ha, the maximum yield was 12 393.69 kg/ha.

Key words: Coupling of water and fertilizer, Maize, Root morphology, Yield

CLC Number: 

• S141