不同施肥深度对直播水稻氮素积累与转移的影响

为了研究不同施肥深度对直播水稻氮素积累与转移及其产量的影响,以天优998和玉香油占为试材,通过设计4个不同的施肥深度,分别为4,8,12,16 cm,依次记为T1、T2、T3、T4,以不施肥为对照(T0),试验采用木箱种植法。结果表明,T2处理水稻拔节期、抽穗期和成熟期叶片及茎鞘氮素积累量、植株氮素积累总量均为最高且显著高于T0和T4处理,氮素积累总量随生育期的推进在成熟期达到最高;T2处理在水稻拔节期、抽穗期和成熟期氮素阶段性积累量最高,且显著高于其他处理,分蘖期至拔节期氮素阶段性积累量在4个生育阶段中最高,2个品种表现一致;T2处理与T0和T1比较还显著增加了水稻灌浆期茎叶氮素表观转移量和氮素表观转移率,T2处理水稻的氮素吸收效率与T1、T3、T4比较,差异达到显著水平;而且,T2和T3处理水稻有效穗数显著高于其他处理,T2处理还提高了水稻结实率以及产量。因此,施肥深度8 cm的处理,不仅能显著提高直播水稻氮素吸收效率,而且还能够增加水稻每穴的有效穗数、结实率以及收获产量,这也说明了T2处理是直播水稻较适宜的施肥深度。

Influences of Different Nitrogen Application Depths on Nitrogen Accumulation and Transfer in Direct-seeded Rice

In order to study the effects of different fertilizer application depths on nitrogen accumulation and transfer in direct-seeded rice,the experiment was conducted using two rice cultivars,Tianyou 998 and Yuxiangy-ouzhan,respectively,in wooden boxes.In this study,the depths of different fertilizer application were designed to 4, 8,1 2,and 1 6 cm below the surface,which were written as T1 ,T2,T3,and T4,respectively.No fertilizer was taken as a control,written as T0.The T2 treatment significantly increased nitrogen accumulation in the leaves,and sheats, and total plants at the booting,heading,and maturity stage,compared to the T0 and T4 treatment,respectively.The highest total nitrogen accumulation was found at the maturity stage.There was significant higher period percentage of nitrogen accumulation at the booting,heading,and maturity stage under the T2 than T0,T1 ,T3 and T4 treatment,re-spectively.The highest period percentage of nitrogen accumulation was found between the tillering and booting stage in Tianyou 998 and Yuxiangyouzhan.Comparing to T0 and T1 ,T2 treatment also significantly improved nitrogen transfer amount and nitrogen transfer efficiency at the grain filling stage.Nitrogen recovery efficiency was recorded for T2 which was significantly higher than T1 ,T3,and T4,respectively.And the number of valid panicle per hill was significantly higher under T2 and T3 than T0,T1 ,and T4 treatment,respectively.The T2 treatment also increased grain filling percentage and yield in Tianyou 998 and Yuxiangyouzhan.The results also demonstrated favorable fertil-izer application depth taken as 8 cm in direct-seeded rice.