播期对甜菜氮素同化及块根产量的影响

Effects of sowing date on nitrogen assimilation and root yield of sugar beet

为确定播期对甜菜氮同化及产量的影响,于2019年在东北农业大学阿城实验实习基地以甜菜品种KWS0143为材料进行田间试验,设置4个播种时期:4月7日(S1)、4月14日(S2)、4月21日(S3)和4月28日(S4),比较分析播期对甜菜氮代谢关键酶、氮肥表观利用率、氮肥农学利用率及块根产量的影响。结果表明,随生育进程推进,各播期叶片及根系硝酸还原酶(NR)、谷氨酰胺合成酶(GS)和谷氨酸合成酶(GOGAT)变化趋势相似,但不同播期间存在差异。叶丛快速生长期,S1与S2处理的叶片及根系NR、GS和GOGAT活性均显著高于S3处理;糖分积累期,S4处理叶片各关键酶活性较S3处理显著升高,S1与S2处理块根各关键酶活性较S3处理显著升高;S1处理氮素积累量和氮肥表观利用率最高,S2处理下块根产量、地下部干重与氮肥农学利用率最高。综上,在此试验条件下4月14日播种可有效促进黑龙江省中部地区甜菜氮素同化进程,提升氮素利用效率,增加块根产量。

In order to determine the effect of sowing date on nitrogen assimilation and yield of sugar beet,field experiments were carried out in Acheng Experimental Base of Northeast Agricultural University in 2019.Four sowing dates were set as the followings:April 7th(S1),April 14th(S2),April 21st(S3)and April 28th(S4).The effects of the sowing dates on key enzymes of nitrogen metabolism,apparent nitrogen use efficiency,agronomic nitrogen use efficiency and root yield of sugar beet were compared and analyzed.The results showed that the trends of nitrate reductase(NR),glutamine synthetase(GS)and glutamate synthase(GOGAT)in leaves and roots of different sowing dates were similar,but there were differences in different sowing dates.During the rapid growth period of leaf clusters,the activities of NR,GS and GOGAT in leaves and roots of S1 and S2 treatments were significantly higher than those of the S3 treatment.During the sugar accumulation period,the key enzyme activities of the S4 treatment leaves were significantly higher than those of the S3 treatment,and the key enzyme activities of the S1 and the S2 treatments were significantly higher than those of S3 treatment.The S1 treatment had the highest nitrogen accumulation and apparent nitrogen use efficiency,and the S2 treatment had the highest root yield,underground dry weight and nitrogen agronomic efficiency.In summary,under the conditions of this experiment,sowing on April 14th could effectively promote the nitrogen assimilation process of sugar beet in the central region of Heilongjiang Province,improve nitrogen use efficiency,and increase root yield.