| The nutrent status of main tobacco-growing soil in Zhumadian region were analysed. The effects of the main mineral nutrition elements on growth,yield and quality of flue-cured tobacco under field experimentions.The results is as follows:1.The soil pH of Queshan county was in proper range,that of Biyang County was higher than Queshan county but it was basic proper for growing tobacco.38.46%soil samples in Biyang County and 63.75%soil samples in Queshan County were low in organic matter(<1.2%).Most of them were low to medium in avail phosphorus,and low to lack in potassium in two Counties.A little of soils were high in ratio of exchangeable calium to exchangeable magnesium,maybe caused lacking of magnesium of tobacco plants.They were rich in avail cuprum,low in exchangeable manganese,low to lack in avail zinc and avail boron.The soils in Biyang County were higher in water-solubility chlorine.Therefor,organic fertilizer should be applied,rate of nitrogen was moderate,rate of phosphorus and potassium fertilizer should be increased properly, and zinc,boron,manganese and magnesium replenished properly,to improved the growth of tobacco plants and yields and quality of tobaccoleaves in Zhumadian main tobacco-growing areas.2.Applying nitrogen,pgosphrous or potassium or any two kinds of them were promoted the growth of flue-cured tobacco plants,increased the yield and quality of tobacco leaves,especially the impacts of nitrogen fertilizer on the yield and quality of flue-cured tobacco leaves were the largest.The effects of combination applying of nitrogen and phosphrous or nitrogen and potassium were better than those of anyone element applying alone of them and combination applying of phosphrous and potassium.In particular,the proportions in flue-cured tobacco leaves chemical components were well coordinated by combination applying of nitrogen phosphrous,and potassium in a certain ratio.That complained the applying fertilizer balancely was important measure to promoting the growth of flue-cured tobacco plants and increased the yield and quality of tobacco leaves.3.It increased significantly yield,value,average price,the proportion of superior tobacco leaf combination applying of magnesium,sulfur and manganese besides applying nitrogen,phosphrous and potassium normally. |
