氮磷配施对旱地胡麻干物质积累和籽粒产量的影响

Effects of Nitrogen Application Combined With Phosphorus on Dry Matter Accumulation and Seed Yield of Rain-fed Flax

为了解决旱地胡麻施肥增产不明显的问题,设2个施氮(纯N)水平:75 kg·hm^(-2)(N_1)、150kg·hm^(-2)(N_2);2个施磷(纯P_2O5)水平:75 kg·hm^(-2)(P_1)、150 kg·hm^(-2)(P_2),共4个施肥处理(N_1P_1、N_1P_2、N_2P_1和N_2P_2),以不施肥为对照(N0P0),研究了氮磷配施对胡麻干物质积累、籽粒产量和水分利用效率的影响。结果表明,氮磷配施促进了胡麻地上部干物质的积累,比N0P0明显增加11.90%~59.29%,且成熟期干物质在籽粒中的分配量和分配比例随施肥量的增加而增大,以N_2P_1最大,比其他处理显著增加7.76%~34.73%和8.07%~9.14%(P<0.05)。与N0P0相比,各施肥处理的开花后干物质积累量及其对籽粒产量的贡献率分别显著增加3.26%~39.06%和5.72%~61.50%。不同氮磷配施水平对胡麻籽粒产量的影响显著,与N0P0相比,N_1P_1、N_1P_2、N_2P_1和N_2P_2的籽粒产量分别显著增加16.21%~21.69%、28.47%~36.05%、44.27%~56.55%、36.34%~47.10%。胡麻的水分利用效率与籽粒产量的变化趋势基本一致,以N_2P_1的水分利用效率最大,N_2P_2次之,分别比N0P0显著增加30.23%~38.54%、20.50%~36.81%。可见,适宜的氮磷配比(N_2P_1:150 kg N·hm^(-2)、75 kg P_2O5·hm^(-2))在增加旱地胡麻干物质累积量、促进土壤水分吸收的基础上,保证了胡麻的高产高效,这为旱区胡麻高产栽培技术提供了理论依据。

In order to solve the problem that increased production after fertilization was not obvious in rain-fed flax, a field experiment was conducted to elucidate effect of nitrogen application combined with phosphorus on dry matter accumulation, seed yield and water use efficiency of flax. Four fertilizer application treatments were set including two nitrogen levels （N1： 75 kg·hm^-2and N2： 150 kg·hm^-2） and two phosphorus levels （P1： 75 kg·hm^-2and P2： 150 kg·hm^-2） which were marked as N1P1, N1P2, N2P1, N2P2, and no fertilization（N0P0） was as the control. The results showed that overground dry matter accumulation of oil flax under the level of nitrogen application combined with phosphorus was markedly increased by 11.90% to 59.29% compared with N0P0. Furthermore, the dry matter distribution amount and proportion in seeds at maturity stage were gradually enhanced with the increase of fertilization rate, and reached the maximum under the N2P1 level which were 7.76% to 34.73% and 8.07% to 9.14% higher than other fertilizer treatments. The dry matter accumulation amount after anthesis and its contribution rate of seeds yield were significantly raised by 3.26% to 39.06% and 5.72% to 61.50% compared with the level of N0P0, respectively. In addition, the effect of nitrogen application combined with phosphorus on seed yield of flax was significant, and the seed yield of N1P1, N1P2, N2P1and N2P2were significantly increased by 16.21%~21.69%, 28.47%~36.05%, 44.27%~56.55% and 36.34%~47.10% compared with N0P0level, respectively. Besides, the changes of water use efficiency was fairly consistent with seed yield, and the N2P1 was the largest followed by the N2P2 which were raised by 30.23%~38.54% and 20.50%~36.81% compared the treatment of N0P0, respectively. Therefore, the optimal ratio of nitrogen and phosphorus which was 150 kg·hm^-2 （N） and 75 kg·hm^-2（P2O5） ensure high yield and high efficiency on the basis of increasing dry matter accumulation amount and improving soil moisture absorption of rain-fed flax, as well as provided a theoretical basis for high yield cultivation techniques of dryland flax.