不同机械化栽培方式下控释肥配比对迟熟中粳水稻产量形成及氮素吸收利用的影响

以优质食味粳稻南粳9108为材料,纯氮270 kg hm–2施氮条件下,设置了钵苗机插、毯苗机插2种栽培方式,将控释肥与速效氮肥以5∶5的比例混合,其中控释肥由4种不同释放期(40、80、100、和120 d)肥料按照1∶4的比例混合形成了3种配比方式,分别为40+80、40+100、40+120,同时设置常规分次施肥(CK)为对照,研究不同机械化栽培方式下控释肥配比对迟熟中粳水稻产量形成以及氮素积累的影响。结果表明,相同肥料处理下,钵苗机插2年产量较毯苗机插分别增加了3.9%和4.9%,其原因是钵苗机插能够提高中后期的光合物质积累,获得较大的穗型,具有更高的每穗粒数、结实率以及千粒重。钵苗机插与毯苗机插栽培方式下,40+80和40+100控释肥处理2年产量均高于CK, 40+100控释肥处理产量最高, 2年较CK分别显著增加7.3%和9.2%,其原因在于40+100控释肥处理具有更高的有效穗数和群体颖花量。与40+80和40+120控释肥处理相比,40+100控释肥处理与南粳9108的养分吸收规律更为匹配,即保证了前期分蘖的发生,又保证了后期稳定的光合物质生产,获得稳定的穗数、穗粒数...

Effects of controlled release fertilizer ratio on yield formation and nitrogen absorption and utilization of late-maturing medium japonica rice under differ-ent mechanized cultivation methods

Rice cultivars of Nanjing 9108 with good taste quality was adopted as material under the pure nitrogen condition of 270 kg hm^-2 in this study.Rice was cultivated with two methods including mechanical transplanting with pothole seedlings(MT)and mechanical transplanting with carpet seedlings(MC).Controlled-release fertilizer and quick-acting nitrogen fertilizer were mixed at a ratio of 5:5.Controlled-release fertilizer was mixed from four different release periods(40,80,100,and 120 days)at a ratio of 1:4 to form three mixing modes(40+80,40+100,and 40+120).Conventional urea split fertilization(CK)was used as a control,and the effects of different controlled-release fertilizer ratios on yield formation and nitrogen accumulation of high-quality japo-nica rice were studied.Under the same fertilizer treatment,compared with mechanical transplanting with carpet seedlings(MC),the two-year yield of mechanical transplanting with pothole seedlings(MT)was significantly increased by 3.9%and 4.9%,re-spectively.The reason was that the transplanting of pothole seedling machine could improve the accumulation of photosynthetic substances in the middle and late stages and obtain larger panicle type with higher grain number per panicle,seed setting rate,and 1000-grain weight.Under the cultivation mode of pothole seedling transplanting and carpet seedling transplanting,compared with CK,the two-year yield of 40+80 and 40+100 controlled-release fertilizer treatments were higher than CK,and the two-year yield of 40+100 controlled-release fertilizer treatments was the highest,which was significantly increased by 7.3%and 9.2%,respec-tively.The reason was that 40+100 controlled-release fertilizer treatment had higher effective panicle number and population glume amount.Compared with 40+80 and 40+120 controlled-release fertilizer treatments,the nutrient absorption law of 40+100 controlled-release fertilizer treatment was more consistent with Nanjing 9108,which not only ensured the occurrence of early tillering,but also ensured the stable production of photosynthetic substances at later stage,thus obtaining stable panicle number,grains per panicle,and 1000-grain weight.Compared with CK,the nitrogen recovery efficiency,nitrogen agronomic efficiency,nitrogen physiological efficiency,and nitrogen partial productivity of 40+100 controlled-release fertilizer treatments were signifi-cantly increased by 10.0%-12.5%,24.6%-30.5%,11.4%-18.6%,and 7.3%-9.1%,respectively.In conclusion,the mechanical transplanting with pothole seedlings(MT)had obvious advantages over mechanical transplanting with carpet seedlings(MC),which was a cultivation method that was conducive to high-quality japonica rice.At the same time,the 40+100 controlled-release fertilizer ratio could better meet the nutrient requirements of good-quality japonica rice at various stages,and could obtain high yield,which could be used as a simplified fertilization scheme for high-quality japonica rice.