红壤性水稻土上钾肥运筹对烤烟产量和品质的影响

Effects of Potassium Application on the Yield and Quality of Flue-Cured Tobacco in the Red Paddy Soil

利用田间小区试验研究了南方红壤性水稻土上K肥用量及基追肥比例对烤烟的施用效果。试验结果表明:相同追肥比例下,烟叶产量、产值为施K(K2O)量270 kg／hm2最高,315 kg／hm2最低;总N和烟碱含量随K肥用量增加而极显著减少(r=-0．99***,r=-0．97***,P<0．001)。相同K肥用量下,烟叶产量基追肥比3:7 最高,5:5最低:上等烟比例、均价、产值、烟叶含K量随追肥比例增加而显著提高。因此,在速效K含量为130 mg／kg的红壤性水稻土上,选择适当的K肥用量,增加追肥比例,能更好发挥K肥的施用效果,提高烟叶含K 量,改善烟叶品质。本试验以施K量270 kg／hm2,基追肥比例3:7为最优组合。

A field trial was conducted in red paddy soil to study effects of K application rate and ratio of basal and sidedressings （BS ratio） of the K fertilizer on growth, yield and quality of flue-cured tobacco. Results showed that when the BS ratios were the same K, the yield and production value were the highest with the treatment applied with 270 kg/hm^2 K（K2O） in total, and the lowest with the treatment applied with 315 kg/hm^2; with the rising of K application rate, the contents of total N and nicotine markedly decreased （ r = -0.99^＊＊＊, r = -0.97^＊＊＊, P〈0.001）. When the K application rates were kept the same, the highest yield of tobacco leaves was obtained in the treatment being 3：7 in BS ratio and the lowest in the treatment being 5：5 in BS ratio. In terms of yield of tobacco leaves, the treatments of BS ratio were in the order of 70%〉30%〉50%, while in terms of proportion of top grade leaves, average price, production value and K content of tobacco leaves were in the order of 70%〉50%〉30%. Therefore, in soils, 130 mg/kg^1 in available K content, keeping a feasible K application rate and increasing the proportion of sidedressing may improve use efficiency of the K fertilizer applied, K content and quality of tobacco leaves as well. In this experiment, the best combination is 270 kg/hm^2 in K application rate and 3：7 in BS ratio.