Abstract: Taking Longya 13 as the material, this paper investigated the effects of synergetic effect of seeding rate + fertilization amount under water stress on the growth, yield and harvest index (HI) of flax. Through correlation analysis, the influence characteristics of different water environment in irrigated/ arid areas on the flax key character factors were revealed, such as yield composition and HI. The results showed that: water stress affected the formation of yield components in irrigation and arid areas, and adapted to extreme environment at the expense of changing the growth and development index of flax. The positive and negative correlations were different between yield and yield components in irrigation and arid regions, and the positive effect factors of flax yield composition were decreased and negative effect factors were increased. Under the same water condition, the synergistic effect of seeding amount and fertilization amount had limited improvement on the yield of flax, and the influence of HI in the arid areas was more prominent than the water stress in irrigation area. The 1 000-grain weight and plant height in the irrigation area played a leading role in promoting yield, and there was no regression analysis in the arid area. The number of grains per plant and the number of fruits per plant in the irrigation area inhibited HI, but 1 000-grain weight promoted. The number of fruits per plant in the arid area was the dominant inhibitory factor for HI. The results indicated that water stress had different focuses on the main effect factors of growth and yield formation in the irrigation and arid area.

Key words: flax, seeding rate, fertilization amount, yield, harvest index, correlation coefficient

摘要： 以陇亚13号为材料，探究水分胁迫下播种量+施肥量协同作用对胡麻生长、产量和收获指数（harvest index，HI）的影响。通过相关性分析，揭示灌区/旱区不同水分环境对胡麻产量构成、HI的关键性状因子影响特征。结果表明:水分胁迫影响灌区/旱区产量构成因子的形成规律,以改变胡麻生长发育指标为代价达到对极端环境的适应性。灌区/旱区产量与产量构成因子间正、负相关性不同，且旱区胡麻产量构成因子的正效应因子减少，负效应因子增加。相同水分条件下，播种量+施肥量协同作用对胡麻产量的提高有限,旱区HI较灌区受水分胁迫的影响更突出。灌区千粒重、株高对产量起主导促进作用，旱区无回归分析。灌区每株结果粒数、单株果数对HI起抑制作用，千粒重起促进作用；旱区单株果数对HI起主导抑制因子,说明水分胁迫对灌区/旱区胡麻的生长及产量形成的主效应因子有不同侧重点。

关键词: 胡麻, 播种量, 施肥量, 产量, 收获指数, 相关系数