Study on response of rapeseed to boron application and critical level of soil available B in Hubei Province

Chino. 从区域角度研究湖北省油菜主产区硼肥施用对油菜（Brassica napus L.）生长及产量的效果，确定目前生产条件下土壤有效硼临界值，为油菜科学施肥提供依据。2005～2006年在湖北省布置30个田间试验研究油菜施硼产量效应，结合土壤有效硼含量确定缺硼临界值。施硼对油菜的营养生长及产量构成因素均有促进作用，30个试验点施硼平均增产油菜籽428 kg•ha-1，平均增产率19.2%，70%的试验增产效果显著，增产量超过500 kg•ha-1的试验点占26.7%；土壤有效硼含量与施硼效果呈极显著负相关；按照不施硼产量相对于施硼处理的90%作为判断标准，土壤有效硼临界值比20年前第二次土壤普查时确立的临界值有所提高。湖北省油菜施用硼肥增产效果显著，现阶段油菜种植的土壤有效硼临界值为0.58 mg•kg-1，大约80%的地块在种植油菜时需要施硼。

Inglés. In order to provide a scientific basis for balanced fertilization, the effect of boron fertilization on growth and yield of rapeseed (Brassica napus L.) was studied and soil critical available B was determined based on field trials in main rapeseed producing region of Hubei Province. Thirty field trials of B fertilizer application to rapeseed were conducted in 2005-2006 growth season. The soil critical value of B deficiency was determined according to the effect of B fertilizer on seed yield and soil available B content. The results showed that B application promoted the vegetative growth and yield components of rapeseed. The average increment with B fertilization was 428 kg•ha-1 and the increasing rate was 19.2% for all 30 trials. Compared to the control (no B treatment), the yield of about 70% trails significantly increased by B application, and the percentage of yield increment more than 500 kg•ha-1 was as high as 26.7% for all trials. The results indicated that the yield increment by B application had significantly negative corretation with soil available B content. Based on the relative yield of CK/+B at 90 percent level, the soil critical available B was 0.58 mg•kg-1 which was higher than that in the 1980s determined by the second nationwide general soil survey achievement. The yield-increasing effect of B fertilizer on rapeseed is notable and the soil critical available B is 0.58 mg•kg-1 in Hubei Province at present. According to the soil B deficiency criterion, it is necessary to apply B fertilizer for about 80% rapeseed cultivated field in Hubei Province.