再生水与微咸水轮灌对向日葵生长和籽粒发育的影响

Effect of Alternate Irrigation with Reclaimed Water and Saline Water on Sunflower Growth and Grain Development

摘要:

干旱半干旱农业区灌溉用淡水资源紧缺，加强再生水资源与地下微咸水资源集约灌溉成为区域种植业持续发展的关键。本文在向日葵关键生育阶段（出苗-现蕾期、现蕾-开花期、开花-成熟期），针对淡水（F）、微咸水（S）和再生水（R）设置3组持续灌溉方式（FFF、SSS、RRR）和6组轮灌方式（SSR、SRS、RSS、SRR、RSR、RRS）。在宁夏银北灌区开展2年野外大田试验，探讨了不同再生水与微咸水轮灌方式对向日葵植株生长特征和籽粒发育特性的影响。结果表明：再生水灌溉引起植株盛花期的非生物胁迫程度相对微咸水灌溉更弱；向日葵出苗-开花期微咸水灌溉促进植株干物质向根分配，再生水灌溉促进植株干物质向茎、叶和花盘分配；再生水灌溉可以显著提高籽粒粗蛋白、不饱和脂肪酸和饱和脂肪酸含量。SRR轮灌方式对应向日葵籽粒相对其他轮灌方式显著增产2.9%~32.7%；RRS轮灌方式相对其他轮灌方式显著降低水分利用效率（19.9%~28.1%）和减小氮、磷利用效率（22.4%~38.0%）。向日葵开花-成熟期再生水灌溉相对微咸水灌溉更有利于提高向日葵籽粒产量和水分利用效率。一定年限内经处理达标的再生水与微咸水轮灌不会导致向日葵籽粒重金属元素含量超标。研究表明，向日葵出苗-现蕾期微咸水灌溉+现蕾-成熟期再生水灌溉方式可有效节约淡水、促进向日葵植株生长发育和籽粒品质提升，可为中国西北缺水农业区再生水和微咸水开发利用提供参考。

Abstract:

The fresh water resources for irrigation are severely scarce in arid and semi-arid agricultural areas, thus the intensive irrigation with reclaimed water resources and underground saline water resources have become a key issue for sustainable development of regional crop farming. According to the key growth stages of sunflower (seedling-squaring stage, squaring-flowering stage, flowering-maturity stage), three groups of continuous irrigation modes (FFF, SSS, RRR) and six groups of alternate irrigation modes (SSR, SRS, RSS, SRR, RSR, RRS) were set up, with fresh water (F), saline water (S) and reclaimed water (R). Two-year field experiment was carried out in Yinbei Irrigation District of Ningxia to explore the effects of different rotation irrigation modes with reclaimed water and saline water on the plant growth characteristics and grain development characteristics of sunflower. The results indicated that the degree of abiotic stress caused by reclaimed water irrigation at sunflower peak flowering stage was lower than that of irrigation with saline water. At the seedling-flowering stage of sunflower, the saline water irrigation promoted the plant dry matter distribution to roots, while the reclaimed water irrigation promoted the plant dry matter distribution to stems, leaves and faceplates. Reclaimed water irrigation at sunflower seeding-flowering stage can significantly improve the content of crude protein, unsaturated fatty acids and saturated fatty acids in grains. The SRR alternate irrigation mode significantly increased the sunflower grain yield by 2.9%~32.7%, compared with other rotation irrigation modes. While, the water use efficiency for RRS alternate irrigation mode was significantly decreased by 19.9%~28.1%, the nitrogen and phosphorus use efficiency was reduced by 22.4%~38.0%, compared with other rotation irrigation modes. Reclaimed water irrigation from flowering to maturity stage was more conducive to improving sunflower seed yield and water use efficiency than brackish water irrigation. Moreover, in a certain number of years, alternate irrigation with treated reclaimed water and saline water would not lead to excessive accumulation of heavy metal elements in sunflower grains. The research result suggested that the mode of saline water irrigation at seeding-squaring stage and reclaimed water irrigation at squaring-maturity stage could effectively save fresh water, promote sunflower plant growth and improve the grain quality, which could provide reference for the development and utilization of reclaimed water and saline water in water-deficient agricultural areas of Northwest China.