Effects Of Phosphorus And Postassium Fertilizers Influence Tuber Yield And Quality And Relevant Physiological Processes Of Potatoes

The present research investigates the effect on the yield, quality and relevant physical indicators of Kexin 4 potato and the other two kinds of potatoes by increasing different quantity of potassium fertilizer. It also studies the effect on the yield, quality and relevant physical indicators of Kexin 12 and Zhongshu 1 by adding potassium fertilizer in different growth stages .The experiment studies the effect on the yield, quality and relevant physical indicators of Kexin 17 by using different quantity of potassium and phosphate fertilizer as well.1. Adding potassium fertilizer (K) can increase the output, dry matter content,starch content of tuber and the rate of large-medium sized potatoes of Kexin 4, Dongnong 303 and Zaodabai. It also increases the chlorophyll content, net assimilation rate and root activity. Although the effect varied with different amounts of K used and the different potato genotypes, the experiment shows K promotes tuber yield, quality and the physiological indicators tests in a high degree of unity. By the data analysis of the experiment, the result shows the yield has a closet correlation with the large - medium sized tuber rate and the net assimilation rate.2. By increasing K (180kg/hm~2) in different growth stages, it increases the yield, tuber starch content, dry matter content and the rate of large - medium sized tubers. K also can improve the net assimilation rate, chlorophyll content and root activity. It is showed K can improve the yield and the quality of these two potato genotypes obviously. That shows the most effective stages of adding K is the early growth stage and next, the stage of making tuberization. By analyzing the tuber yield, quality and the physical indicators, we can find that the yield is most closely related to the large and medium-sized tuber rate and net assimilation rate.3. By combined adding K and P to Kexin 17 potato, its tuber yield, starch content, dry matter content and the rate of large and medium-sized tuber are improved. The experiment shows that various kinds of adding the fertilizer gain different results and K makes greater effect on the yield, quality and the relevant physical indicators than P does. Combination of K and P shows a better performance than any single fertilizer does. By the data analysis we can know that the yield has a closet correlation with the large medium sized tuber rate and the net assimilation rate.