薏苡氮磷钾养分吸收分配及利用特征

Nitrogen, Phosphorus, and Potassium in Adlay: Uptake, Distribution and Utilization Characteristics

旨在为薏苡科学施肥及高产潜力挖掘提供理论依据。以4个薏苡品系为试验材料,于2018—2019年进行大田试验,分析其在不同生育时期氮磷钾(NPK)元素的吸收、分配及利用规律。结果表明,4个薏苡品系的全株总生物量干重在20.5~24.7 t/hm^(2),地上部分生物产量干重在18.4~22.6 t/hm^(2)之间,但是籽粒产量相对偏低,产量为1969.2~3109.1 kg/hm^(2)。从薏苡抽穗至籽粒成熟,整个植株对NPK元素的吸收和积累量均有增加;N元素在抽穗至扬花期主要分布在茎鞘和叶片,至完全成熟籽粒中N素积累及分配均高于其他部位,而PK元素则主要分配在茎鞘部位。薏苡植株总NPK的吸收量平均为183.93 kg/hm^(2)、62.57 kg/hm^(2)和320.56 kg/hm^(2),平均吸收比例为N:P:K=2.94:1:5.12。薏苡NPK元素的籽粒生产效率和收获指数相对偏低,每100 kg籽粒对NPK养分需求量分别为5.6~7.3 kg,1.7~2.4 kg,8.0~15.0 kg。4个薏苡品系整体物质累积能力强、生物量大,但籽粒对NPK吸收分配和利用效率相对较低,高产潜力的挖掘仍有很大的提升空间。

To provide a theoretical basis for scientific application of fertilizer and yield improvement, four adlay lines were used as materials in the field experiment in 2018—2019. The absorption, distribution and utilization of nitrogen(N), phosphorus(P) and potassium(K) were analyzed at different growth stages. The results showed that the total biomass dry weights of the four adlay lines ranged from 20.5 t/hm^(2) to 24.7 t/hm^(2).The biomass dry weights of the above-ground parts were 18.4-22.6 t/hm^(2), but the grain outputs were relatively low, which was 1969.2-3109.1 kg/hm^(2). N, P, K absorption and accumulation increased during heading to maturing period;nitrogen element was accumulated mainly in leaf and stem tissues in heading and flowering period, while grains had more N accumulation than other plant parts, and P, K were mainly accumulated in stems. The total absorption amounts of N, P, K were 183.93 kg/hm^(2), 62.57 kg/hm^(2) and 320.56 kg/hm^(2) in average, respectively, with a ratio of N: P: K=2.94: 1: 5.12. In addition, the N, P, K use efficiency for grain output and harvest indices were relatively low, and the N, P, K requirement per 100 kg grain was 5.6-7.3 kg,1.7-2.4 kg and 8.0-15.0 kg, respectively. It is concluded that the biomass is large in the four adlay lines with robust dry matter accumulation, but the N, P, K using and distribution efficiency for grain output are relatively low, indicating that there is still potential for improving the adlay yield.