滴灌条件下水肥耦合对苹果幼树生长与生理特性的影响

Effects of Water and Fertilizer Coupling on Growth and Physiological Characteristics of Young Apple Tree under Drip Irrigation

摘要:

为探明半干旱区苹果树科学合理的灌溉和施肥制度，进行了滴灌条件下北方半干旱地区水肥耦合效应对苹果幼树生长与生理特性影响的试验，灌水设4个水平，施肥设3个水平，其中灌水处理为田间持水率的75%~90%（W1）、65%~80%（W2）、55%~70%（W3）和45%~60%（W4），施肥处理为N、P2O5、K2O与风干土质量比分别为0.9、0.3、0.3g/kg（F1），0.6、0.3、0.3g/kg（F2），0.3、0.3、0.3g/kg（F3）。结果表明：不同水肥耦合处理下苹果幼树各生育期植株生长量、叶面积和干物质量最大值均出现在F1W2处理，最小值均出现在F3W4处理，植株生长量和叶面积在萌芽开花期、新梢生长期、坐果膨大期和成熟期较F1W1处理分别增加了6.9%、6.2%、11.0%、2.7%和9.3%、5.8%、5.0%、3.3%，生长指标一定程度上可以反映作物的生理特性。随着苹果幼树的生长，不同水肥耦合处理对苹果幼树叶片SPAD的影响越来越大，苹果幼树全生育期耗水量随灌水量和施肥量的增加呈递增的趋势，在F1W2处理下水分生产率均达到最大值（2.43kg/m3），且与F1W1处理相比增加了14.6%，耗水量却减少了12.2%。苹果幼树净光合速率、蒸腾速率和气孔导度的最大值均出现在F1W1处理，F1W2处理与其相比分别降低了4.2%、9.7%和4.2%，但水分利用效率提高了5.9%，最大值也出现在F1W2处理。综上，F1W2水肥处理为最佳的水肥耦合模式，是最佳的灌溉和施肥制度。

Abstract:

In order to explore the scientific and reasonable irrigation and fertilization system for apple trees in semi-arid region, the effects of water and fertilizer coupling effect on the growth and physiological characteristics of young apple trees in northern semi-arid region under drip irrigation were studied. Four irrigation levels and three fertilization levels were set, among which irrigation treatment was 75%~90% (W1), 65%~80% (W2), 55%~70% (W3) and 45%~60% (W4) of field water holding capacity. The mass ratios of N, P2O5, K2O to airdried soil were 0.9g/kg, 0.3g/kg, 0.3g/kg (F1), 0.6g/kg, 0.3g/kg, 0.3g/kg (F2) and 0.3g/kg, 0.3g/kg, 0.3g/kg (F3), respectively. The results showed that: under different water and fertilizer coupling treatments, the maximum value of plant growth, leaf area and dry matter weight of young apple trees at each growth stage appeared in F1W2 treatment, and the minimum value appeared in F3W4 treatment. Compared with F1W1 treatment, plant growth and leaf area were increased by 6.9%, 6.2%, 11.0%, 2.7% and 9.3%, 5.8%, 5.0% and 3.3%, respectively, at germination and flowering stage, shoot growth stage, fruit setting and maturity stage. The growth index could reflect the physiological characteristics of crops to some extent. With the growth of the trees, different water and fertilizer coupling treatments had more and more influence on the SPAD value of apple trees-leaves. Water consumption of apple trees during the whole growth period was increased with the increase of irrigation amount and fertilizer amount. Water productivity of apple trees under F1W2 treatment reached the maximum of 2.43kg/m3, and increased by 14.6% compared with that of F1W1 treatment and water consumption was decreased by 12.2%. The maximum value of net photosynthetic rate, transpiration rate and stomatal conductance of young apple trees appeared in F1W1 treatment, and that of F1W2 treatment were decreased by 4.2%, 9.7% and 4.2%, respectively, but water use efficiency was increased by 5.9%, and the maximum value also appeared in F1W2 treatment. In conclusion, F1W2 water and fertilizer treatment reached the best water and fertilizer coupling mode and was the best irrigation and fertilization system.