Effects Of Fertilizers Rates On The Growth,Yield,Nutrients Accumulation And Distribution Of Spring Potato In Hunan

Potatoes,also known as yam eggs,artichokes,etc.,are native to South America and are annual herbaceous tuber crops belonging to the genus Solanaceae.The level of potato production and quality are mainly affected by the characteristics of the varieties,and the external environment?soil,climate,etc.?will also have an impact on them.But the greatest impact have been caused by fertilizers.How to increase the output of potato in Hunan Province and reduce the use of fertilizer is of great significance.In this study,how to make full use of the planting of potato in winter fields in Hunan to obtain high yields,and what varieties are suitable for cultivation in lownitrogencondition,andthe best fertilization amount per unit area was discussed.This results hope to provide basis for the development of potato production in winter-free fields in Hunan Province.The main findings are as follows:1.The effects of nitrogen and potassium rates on the growth and yield of potato were studied.The results showed that:the leaf chlorophyll content increased with the increase of nitrogen application rate,and the SPAD value was positively correlated with the increase of nitrogen application rate.The results showed that the plant height and stem diameter were increased with the increase of nitrogen application rate during tuber initiation and the tuber bulking.There were significant positive correlations between plant height and stem diameter with nitrogen application rate.The dry weight of total plant,above-ground and under-ground parts of potato plant reached with the increase of nitrogen application rate during tuber maturation.There were significant positive correlations between the dry weight with nitrogen application rate.The yield of potato increased with the increase of nitrogen application rate,and the average yield was the highest with 28707.25 kg/hm² at 225kgN/hm².There were significant positive correlations between potato yield with nitrogen application rate,and significant negative correlation between dry matter content and nitrogen application rate.2.The effects of nitrogenphosphorus and potassiumrates on the growth,yield and nutrients accumulation and distribution of potato were studied.The results showed that the height of potato increased with the increase of N application rate in tuber initiation stage.The SPAD value of leaves of potato plantlets during tuber expantion period increased with the increase of nitrogen application rates,and the maturity period increased with the increase of phosphorus application rates.With the increase of nitrogen application rates,the dry weight of potato plants and dry weight of all parts showed an increasing trend.The results of regression analysis showed that increasing nitrogen and potassium rates in a certain range was beneficial to the increase of potato yield,and there was an interaction effect between nitrogen and potassium.Nitrogen contents and accumulation in potato tubers,stems and leaves were significantly positively correlated with nitrogen application rates.With the increase of nitrogen and potassium rates,the distribution ratio of nitrogen and potassium in potato stems showed an upward trend.In addition to the treatment without nitrogen and potassium,the distribution rates of nitrogen and potassium in tubers showed an upward trend.With the increase of phosphorus rates,the phosphorus content and accumulation of all parts of the potato showed an upward trend.Under this experimental conditions,the recommended fertilization schemes are:pure N 90kg/hm²,P₂O₅ 120kg/hm²,and K₂O 150-225kg/hm².3.At the rate of 0 kgN/mu and 15 kg N/mu nitrogen,the response of 54 potato varieties to two differentnitrogen rates was studied.The results showed that there were significant differences in plant height,stem diameter,SPAD,tuber weight,tuber number,and potato weight of different varieties under the same nitrogen application rate.The yield of nitrogen fertilizer rate of 15kgN/mu in most varieties was higher than 0kgN/mu rate.The effect of non-nitrogen application on plant height was greater than stem diameter and SPAD value,and the effect on tuber number per plant was greater than that of single tuber weight.Plant height,stem diameter,tuber number per plant,and tuber weight per plant were significantly and positively correlated.The nitrogen partial productivity of"Jizhangshu 8"was319.86kg/kgN,and the yield per plant was 381.67g/plant when nitrogen was not applied.It was a high N utilization ratevariety.