The Effect Of Red Kidney Bean Growth And Yield And Soil Fertility On Combined Application Of N, P And K

A two-year fixed position experiment with the "3414" experimental design and the "British Red" variety of red kidney bean as experimental crop was conducted to study the effects of NPK combination application on the plant height, photosynthetic indexes, dry matter accumulation and distribution, nutrient accumulation and distribution, grain quality, yield and its related factors of red kidney bean, the soil nutrient contents, and the farmland water consumption in the growth period of red kidney bean. The results showed that:?1? The plant height of red kidney bean increased with the increase of nitrogen fertilizer and phosphate fertilizer, but it decreased with the increase of potassium fertilizer. The base stem diameter of red kidney bean increased first and then decreased with the increase of nitrogen fertilizer and phosphate fertilizer, but it increased with the increase of potassium fertilizer. The LAI of red kidney bean increased with the increase of nitrogen fertilizer, but it decreased with the increase of phosphate fertilizer and potassium fertilizer. The LAD of red kidney bean increased with the increase of nitrogen fertilizer, but it decreased with the increase of phosphate fertilizer, and it increased first and then decreased with the increase of potassium fertilizer. The effects of nitrogen, phosphorus, and potassium fertilizers on the node number of main stem and the chlorophyll content of red kidney bean were not significant.?2? The accumulation dry matter of red kidney bean increased with the increase of nitrogen fertilizer and increased first and then decreased with the increase of phosphate fertilizer, but it decreased with the increase of potassium fertilizer. The total nitrogen, phosphorus, and potassium contents of red kidney bean plants all increased with the increase of nitrogen fertilizer and increased first and then decreased with the increase of phosphate fertilizer, but decreased with the increase of potassium fertilizer. The demand of red kidney bean for each nutrient element was in the order of N>K₂O>P₂O₅. The demand quantities of red kidney bean for N was about 5.49 kg, P₂O₅ was about 1.33 kg, and K₂O was about 4.9 kg per 100 kg grain yield under the conditions of this experiment.?3? There had some effects of N, P, and K combination application on soil nutrient contents, but the affective trends were all not significant. The farmland water consumption increased with the increase of potassium fertilizer in the growth period of red kidney bean, but the water use efficiency decreased with the increase of potassium fertilizer.?4? The effects of N, P, and K combination application on the grain quality of red kidney bean were not significant. The yield of red kidney bean increased with the increase of nitrogen fertilizer, but decreased with the increases of phosphate fertilizer and potassium fertilizer in 2014, while the yield of red kidney bean increased with the increases of nitrogen fertilizer, phosphate fertilizer, and potassium fertilizer in 2015.?5? Based on the regression analysis of the three factors of nitrogen, phosphorus, and potassium with the yield of 2014, when the amount of fertilizer was N 132.03 kg/hm², P₂O₅160.02 kg/hm² and K₂O 104.80 kg/hm², the highest yield of red kidney bean was 2627.26 kg/hm², the yield of red kidney bean was 2622.52 kg/hm² when the optimum fertilizer rate of N 120.49 kg/hm², P₂O₅150.12 kg/hm², and K₂O 105.2 kg/hm². The yield of 2015 red kidney bean and the three factors of nitrogen, phosphorus, and potassium were not successful fitted.