氮素供应对章丘大葱生长和氮素营养的影响

Effects of Nitrogen Supply on Growth and Nitrogen Nutrition of Chinese Onion

为研究氮素供应对大葱生长和氮素营养的影响,以章丘"大梧桐"品种为试材,设置0、210、280、420kg/hm2 4个供氮水平,通过动态取样,监测大葱全生育期植株各器官的干物质积累和养分吸收,分析不同处理对大葱产量及品质的影响。结果表明:大葱生长呈"S"型,定植后一个月间处于缓苗越夏期,生长停滞,干物质积累及氮素吸收几乎为零。8-10月份大葱快速生长,月均每株积累量分别达1.5g、3.2g和6.4g,同时对氮素吸收量增加,分别为23.7kg/hm2、25.5kg/hm2和35.7kg/hm2。施氮能显著增加大葱干物质积累量及氮素吸收量,至收获两者分别提高21.1%和12.1%。施用氮肥能实现增产增收,然而供氮不足与过量都会使两者失衡。从品质来看,氮肥能提高大葱可食部位维生素C含量,但可溶性糖含量略有降低。大葱施氮量为280kg/hm2时,产量、品质和经济效益最高。

In order to research the effects of nitrogen supply on the growth and nitrogen nutrition of Chinese onion,field trial with four nitrogen levels（0,210,280,420 kg/hm2）were conducted to investi- gate the accumulation of dry matter and nutrients uptake in different plant organs during the whole growth period of Chinese onion,and analyzed the synchronous regulation effect between the yield and quality. The results showed that the growth curve of Chinese onion was S-type. The growth of Chi- nese onion retarded for one month after field planting, named as seeding recovering stage and nearly without dry matter accumulation and nitrogen uptake. From August to October, the Chinese onion grew rapidly,and the monthly mean accumulations were 1.5 g per plant,3.2 g per plant and 6.4 g per plant respectively. The nitrogen absorption amounts were also increased and reached 23.7 kg/hm2 , 25.5 kg/hm2 and 35.7 kg/hm2 respectively. The nitrogen fertilizer could increase the dry matter accu- mulation and nitrogen absorption amounts significantly, with 21.1% and 12.1% increase by the end of harvest, respectively. Using nitrogen fertilizer could increase yield and benefit, but deficiency and ex- cess supply of nitrogen also result in unbalance. Nitrogen fertilizer could increase the content of vita- min C in the edible parts of Chinese onion and decrease the content of soluble sugar. The yield, quality and economic benefit were the highest under the conditions of 280 kg/hm2 nitrogen fertilizztion.