The Effects of Water and Fertilizer Coupling on Plant and Soil Nitrogen Characteristics and Fruit Growth of Rabbiteye Blueberry Plants in a Semi-Arid Region in China

Abstract

To evaluate the effects of nitrogen (N) and irrigation coupling on the soil N distribution, plant N utilization, and fruit yield of rabbiteye blueberries (Vaccinium virgatum), a field experiment was designed using two factors (water and fertilizer application) with four levels of irrigation and three levels of fertilization, and a control. Under the different water and fertilizer combinations, N primarily accumulated in the leaves. Irrigation and N application within appropriate ranges (pure N ≤ 29 g/plant and irrigation volume ≤ 2.5 L/plant) significantly improved the blueberry fruit yield. Increases in water and N within these ranges promoted the effective accumulation of N in various organs and the absorption and utilization of N in the plants, which ultimately promoted blueberry yield. With increased N application rate, the nitrate N content of the 0-20 cm and 20-50 cm soil layers increased. With increased irrigation volume, the nitrate N content of the 0-20 cm soil layer decreased, while the nitrate content in the 20-50 cm soil layer increased. Low N and moderate water treatments resulted in high fruit yields and reduced nitrate N retention in the soil. Under these conditions, the economic input-output ratio was high and the soil N accumulation was low, and thus the economic and ecological benefits were maximized.

Effects of nitrogen fertilization combined with subsurface irrigation on alfalfa yield, water and nitrogen use efficiency, quality, and economic benefits

“…Appropriate amount of water and fertilizer input can improve crop water and fertilizer use efficiency to a certain extent, save costs, and obtain the optimal yield and economic benefits ( Guo et al., 2022 ). In this study, the net income was the largest under the W 2 N 2 treatment, increasing by 87.80% compared with the lowest value obtained under the W 1 N 0 treatment.…”