旱直播对水稻穗部性状、产量和经济效益的影响

Effects of dry direct seeding on panicle characters,yield and economic benefits of rice

以黑龙江省主栽水稻品种龙粳31为试验材料,常规插秧为对照,研究旱直播条件下水稻穗部性状、产量和经济效益的变化。结果表明:水稻穗部性状的变异均表现为旱直播>常规插秧,二次枝梗数变异系数最大,在40.49%~60.19%;相关分析也表明,二次枝梗数是影响旱直播条件下水稻单穗重的主要因素。旱直播条件下水稻穗数·m^(-2)与穗粒数在年际间的变化相对稳定,结实率、千粒重、生物产量和经济系数均表现为常规插秧>旱直播;3 a间,旱直播方式下水稻平均实测产量为7.78 t·hm^(-2),较常规插秧降低5.58%;相关分析表明,穗数与生物产量是影响常规插秧条件下水稻产量的最主要因素,穗数与穗粒数是影响旱直播条件下水稻产量的主要因素。与常规插秧相比,旱直播方式下水稻在总物化成本和总劳动力成本上节约2802.0元·hm^(-2),纯效益增加1528.0元·hm^(-2),因此,旱直播种植方式下水稻产量虽然略低于常规插秧,但能降低农民生产成本,增加经济收入,提高生态效益。

Taking Longjing 31,a main rice variety in Heilongjiang Province as experimental material and conventional transplanting as control,changes of panicle characters,yield,and economic benefits of rice under dry direct seeding were studied.The results showed that the variation of panicle characters of rice was as follows:dry direct seeding>conventional transplanting,and the coefficient of variation of secondary branch number was the largest,ranging from 40.49%to 60.19%.Correlation analysis also showed that the number of secondary branches was the main factor affecting the single panicle weight of rice under the condition of dry direct seeding.The changes of panicle number·m^(-2)and grain number per panicle were relatively stable between years,and seed setting rate,1000-grain weight and biological yield under conventional transplanting were higher than those of under dry direct seeding.In the three years,the average measured yield of rice under dry direct seeding was 7.78 t·hm^(-2),which was 5.58%lower than that of conventional transplanting.The correlation analysis showed that panicle number and biological yield were the most important factors affecting rice yield under the condition of conventional transplanting,and panicle number and grain number per panicle were the main factors affecting rice yield under the condition of dry direct seeding.In comparison,the dry direct seeding method saved 2802.0 Yuan·hm^(-2)in total physical and chemical cost and total labor cost,and increased 1528.0 Yuan·hm^(-2)in net benefit although the rice yield under dry direct seeding mode was lower than that of conventional transplanting.Therefore,the dry direct seeding could reduce farmers’production cost,increase economic income,and improve ecological benefits.