镁肥基施及后期喷施对油菜产量与品质的影响

Effects of spraying magnesium on the yield and quality of oilseed rape under different magnesium fertilizer application rates

在大田条件下,研究了镁肥基施及后期喷施对直播冬油菜产量与品质的影响,为冬油菜科学施肥提供理论依据。试验采用裂区设计,主处理为基施镁肥,用量分别为MgO 0、15、30、45、60 kg/hm^2;副处理为叶面喷施清水和镁肥,于油菜终花期(即播种后180 d)喷施等量(750 L/hm^2)清水和0.5%硫酸镁。结果表明:(1)镁肥基施显著提高了油菜产量和产油量,与不施镁相比,施镁的油菜产量和产油量分别增加了370~675和253~409 kg/hm^2,增幅分别为14.08%~25.68%和21.12%~34.19%。(2)镁肥基施及后期喷镁可进一步提高油菜产量和产油量,与喷水相比,喷镁的油菜产量和产油量分别增加了89~267和44~138 kg/hm^2,增幅分别为2.74%~9.36%和2.81%~9.56%。基施MgO 15 kg/hm^2时,喷施镁肥的油菜产量和产油量增产效果最佳,分别为266和138 kg/hm^2;基施镁肥超过MgO 30 kg/hm^2时,喷施镁肥的增产效果不明显。因此,在土壤交换性镁含量界于缺乏与潜在缺乏时,油菜基施MgO 30~45 kg/hm^2即可满足整个生育期的镁养分需求;基施镁肥用量较低(MgO 15 kg/hm^2)时,后期喷施叶面镁肥可以达到相应的增产效果。

In this study,the effects of magnesium application on the yield and quality of oilseed rape were discussed under the field conditions,which provided a theoretical basis for scientific fertilization of oilseed rape.The test used the crack zone design,the main treatment was the amount of magnesium fertilizer with MgO 0,15,30,45,60 kg/hm^2 respectively;the secondary treatment was the foliar spray of water and magnesium fertilizer.An equal amount(750 L/hm^2)of water and 0.5%magnesium sulfate were sprayed at the end of flowering period(sowing after 180 days).The results showed that:(1)Application of magnesium fertilizer significantly increased the yield and oil production of oilseed rape.Compared with no application of magnesium,the yield and oil production of fertilized magnesium increased by 370~675 and 253~409 kg/hm^2,respectively,and the increased rate were 14.08%~25.68%and 21.12%~34.19%,respectively.(2)Magnesium fertilizer application and later spraying of magnesium further increased the yield and oil production of rapeseed.Compared with water spray,the yield and oil production of magnesium sprayed oilseed rape increased by 89~267 and 44~138 kg/hm^2,respectively,and the increase rate were 2.74%~9.36%and 2.81%~9.56%,respectively.When the applied magnesium fertilizer was MgO 15 kg/hm^2,the yield of rapeseed and oil production increased best,which were 266 and 138 kg/hm^2,respectively.When the application of magnesium fertilizer exceeds MgO 30 kg/hm^2,the effect of magnesium injection was not obvious.When the soil exchangeable magnesium content was between the lack and the potential lack,the base application of MgO 30~45 kg/hm^2 magnesium fertilizer can meet the magnesium nutrient requirements of the oilseed rape throughout the growing period;when the base magnesium fertilizer is MgO 15 kg/hm^2,spraying magnesium at the end of the period can help to achieve the best effect.