穗肥运筹对不同秧龄机插超级稻宁粳1号产量及群体质量的影响

Effect of Panicle Nitrogen Fertilizer Management on Yield and Population Quality in Mechanical Transplanted Super Rice Ningjing 1 with Different Seedling Ages

以超级稻宁粳1号为材料,研究穗肥施用时间对不同秧龄机插水稻产量及其群体质量的影响。结果表明,相同穗肥施用条件下,适龄机插水稻的产量、各生育阶段的群体生长速率、茎蘖动态、叶面积指数、光合势等均优于超秧龄移栽水稻。适龄移栽并于叶龄余数4、3(D4-3)等量施用穗肥时,其产量、拔节至抽穗和抽穗至成熟阶段的群体生长速率、茎蘖成穗率、抽穗后的叶面积指数和群体光合势、抽穗期有效叶面积及其比率、高效叶面积及其比率、上三叶的叶片披垂度均高于叶龄余数5、3(D5-3)和叶龄余数5、4(D5-4)时等量施用穗肥的处理。而超秧龄移栽时,D5-4处理的产量、抽穗至成熟阶段的群体生长速率、拔节后各生育时期的群体茎蘖动态、群体叶面积指数、有效分蘖临界叶龄期(N–n)后的群体光合势、抽穗期有效叶面积和高效叶面积、基部3节间长度及3节间总长占秆长比例均优于D5-3和D4-3处理。说明机插水稻适龄移栽对水稻高产的获得尤为重要。适龄移栽时,穗肥于叶龄余数4、3等量施用可以形成良好的群体获得高产,而在超秧龄移栽时,将穗肥施用时间适当提前到叶龄余数5、4,可以促进部分动摇分蘖转化为有效分蘖并最终成穗,适当弥补秧苗因超秧龄移栽而造成的生长量不足,但穗肥的提前施用也使得基部节间过度伸长,增加了倒伏的风险。

Adopting super high yield rice Ningjing 1 as material,the effect of panicle nitrogen fertilizer application time on yield and population quality of transplanted seedlings with different ages was studied.The results showed that,with the same panicle nitrogen fertilizer application time,rice yield,growth rate of rice population,dynamics of culm and tillers number,leaf area index and photosynthetic potential of right age seedlings were all better than those of overage seedlings in mechanical transplanted rice production.With the right age seedlings,when the panicle nitrogen fertilizer applied equally at the fourth leaf age from top and at the third leaf age from top（D4-3）,rice yield,growth rate of population,percentage of productive tiller,leaf area index and photosynthetic potential after heading,leaf area of productive tillers at heading and its ratio,leaf area from flag leaf to the 3rd leaf from top of productive tillers at heading and its ratio,the drop angle of top three leaves were all higher than those when the panicle nitrogen fertilizer applied equally at the fifth leaf age from top and at the third leaf age from top（D5-3） or applied equally at the fifth leaf age from top and at the fourth leaf age from top（D5-4）.With the overage seedlings,when the panicle fertilizer applied at D5-4,rice yield,growth rate of population from heading to maturing,dynamics of culm and tillers number and leaf area index after elongating,photosynthetic potential after the critical stage of productive tillers,leaf area of productive tillers and leaf area from flag leaf to 3rd leaf from top of productive tillers at heading,the length of basal three internodes of stem and its ratio to the whole stem were all higher than those when the panicle nitrogen fertilizer applied equally at the fifth leaf age from top and at the third leaf age from top D5-3 or applied at D4-3.The results indicated that seedling age is important for high yield of mechanical transplanted rice.Using right age seedlings is helpful for forming the high quality rice population and obtaining high yield when the panicle nitrogen fertilizer applied at D4-3.Instead,with the overage seedlings,the early applying of panicle nitrogen fertilizer,such as applying at D5-4,would promote some shaky tillers to be transformed into effective tillers and consequently form the ears,which provides a compensation for some insufficient growth due to transplanting with overage rice seedlings.However,the early applying of panicle nitrogen fertilizer would elongate the basal internodes of stem excessively and increase the risk of lodging.