【摘要】 以稻花香2号为试验材料,采用大田试验,设置手工移栽、起垄旱直播和免耕旱直播3种处理,研究优化施肥条件下直播水稻钾素吸收、分配规律,以期为寒地直播水稻合理施用钾肥提供理论依据。结果表明,抽穗期之前,直播处理水稻叶片钾含量低于手工移栽处理,茎鞘钾含量高于手工移栽处理;抽穗期以后,直播处理水稻叶片和穗的钾含量均高于手工移栽处理,而茎鞘钾含量低于手工移栽处理,起垄旱直播处理水稻茎鞘的钾含量高于免耕旱直播处理。在整个生育期,直播处理水稻叶片、茎鞘、穗及地上部分钾积累量总体上均低于手工移栽处理,且免耕旱直播处理低于起垄旱直播处理。在整个生育期,直播处理水稻各器官中钾的分配规律与手工移栽处理相同,钾素均主要分布在茎鞘中,叶片次之,穗中最少。抽穗期之后,直播处理水稻叶片中钾分配比例高于手工移栽处理,茎鞘中钾分配比例低于手工移栽处理,抽穗期之前趋势总体相反;抽穗后15 d之后,直播处理水稻穗中钾素分配比例高于手工移栽处理。虽然起垄和免耕旱直播处理较手工移栽处理极显著降低了水稻有效穗数,但同时极显著提高了穗粒数和结实率,且千粒质量和产量均与手工移栽处理无显著差异。更多还原

【Abstract】 In order to study K uptake and distribution of direct-seeded rice in cold region under optimized fertilization,a field experiment was conducted with rice variety Daohuaxiang No. 2,namely transplanted rice,ridge direct-seeded rice and no-tillage direct-seeded rice,so as to provide a theoretical basis for reasonable application of K fertilizer for rice. The results showed that K contents in leaves of direct-seeded rice were lower than that of transplanted rice,and K contents in stems of direct-seeded rice were higher than that of transplanted rice before heading stage. After heading stage,K contents in leaves and panicles of direct-seeded rice were higher than that of transplanted rice,K contents in stems were opposite,and K contents of ridge direct-seeded rice stems were higher than that of no-tillage direct-seeded rice. K accumulation in leaves,stems,panicles and total accumulation in above ground parts of direct-seeded rice were lower than that of transplanted rice,no-tillage direct-seeded rice were lower than that of ridge directseeded rice during whole growing season. During the whole growing season,K distribution in direct-seeded rice was the same as that in transplanted rice. K was mainly distributed in the stems,the second was in the leaves,and the least was in the panicles. After heading,K distribution ratio in leaves of direct-seeded rice were higher than that of transplanted rice,and in stems were lower than that of transplanted rice,theoverall trend was opposite before heading stage. K distribution ratio in panicles of direct-seeded rice were higher than that of transplanted rice at 15 d after heading. Compared with transplanting,direct-seeding significantly reduced effective panicles,but significantly improved the grain number per panicle and seed setting rate. As a result,1 000-grain weight and yield of direct-seeded rice had no significant difference compared with transplanted rice.更多还原