Effects Of Irrigation And Fertilization On Grape Growth And Research On Diagnosis Index Of Water And Fertilizer Deficiency In Semi-humid Area

Irrigation and fertilization have an important impact on the growth quality of crops.As a fruit crop that is widely planted worldwide and has important economic value,grapes not only consume more water but also require more fertilizer.Most of the suitable grape growing areas in China have problems of water shortage and unreasonable fertilization.The reasonable irrigation and fertilization system can achieve the purpose of promoting water and fertilizer to promote water,in order to achieve water?saving and high?yield and high?efficiency in agricultural production,it is necessary to systematically study the reasonable irrigation and fertilization technology of grapes.By carrying out irrigation and fertilization field trials at the Yangling Weir Grape Farm in Shaanxi,the effects of different treatments on grape growth and fertilization process were analyzed to obtain an optimal fertilization system based on quality indicators,and by monitoring the leaf temperature,stem diameter,The changes of liquid flow and other conditions,the analysis of the relationship between the grape physiological indexes and their influencing factors under different fertilization treatments,provides a theoretical basis for the diagnosis of water and fertilizer deficiency.The main findings are as follows:(1)The content of soil available nitrogen varies greatly with time.The consumption of available nitrogen in the new shoot growth period-flowering period is more,while the consumption of available potassium in the fruit expansion period and coloring mature period is more.slow.Therefore,more nitrogen fertilizer can be applied in the new growth period than in the later period,and more potassium fertilizer can be applied in the later period.However,it is not appropriate to apply too much nitrogen fertilizer during the growth period.The fruit cannot be recovered to the previous level after being picked.(2)The amount of fertilization has a significant effect on the growth quality of grapes.Increasing the amount of fertilization within a certain range can have a significant positive effect on the new shoots,canopy coverage,particle size,grain weight,soluble sugar,vitamin C and other indicators of grapes Effect,in this experiment,when the fertilization amount is574.7 kg/hm~2,it will have an adverse effect on the new shoots,canopy coverage,grain weight,color index,etc.of the grape;irrigation in this experiment has little effect on the quality of grape growth;The fuzzy comprehensive evaluation method was used to evaluate the grape fertilization system.The optimal fertilization treatments were as follows:nitrogen application rate was 193kg/hm~2,phosphorus application rate was 116kg/hm~2,and potassium application rate was 232kg/hm~2.(3)The stem flow of grapes under different treatments showed obvious diurnal variation,and the diurnal variation curve was in the shape of"several".The stem flow rate under different fertilization treatments was:the stem flow rate was the highest when fertilization was 479 kg/hm~2,and the fertilization was 383.4 kg/hm~2.Secondly,the minimum stem flow rate is 574.7 kg/hm~2for fertilization;on cloudy days,the stem flow starts and peaks later than sunny days.Under different weather conditions,the stem flow rate is positively correlated with net radiation,saturated water vapor pressure difference,and air temperature,but with relative humidity.Negative correlation;different fertilization rates will change the response of stem flow rate to meteorological factors.Net radiation is the main meteorological influence factor of stem flow rate under different treatments,and the determination coefficients are all greater than 0.791.(4)The daily maximum shrinkage MDS,daily increase DI and leaf?air temperature difference of grape stem diameter are all related to soil water content.Among them,the grape MDS index reaches the coefficient of soil water content determination during the flowering and coloring maturity 0.05 significant level;the grape DI index reached the 0.05significant level during the fruit expansion period and the soil water content determination coefficient;the leaf?air temperature difference reached the 0.01 significant level with the0?10cm soil layer water content during the entire growth period.However,the determination coefficients of all indicators are relatively small,and the indicators used to diagnose the soil moisture status also need to eliminate the influence of other influencing factors.There was no significant correlation between grape MDS,leaf?temperature difference and soil available nutrients,and the daily increase in DI and the content of available nutrients reached a significant level of 0.05.