Effect Of Humic Acid On Photosynthetic And Nutrient,Yield And Quality Of Potato Under Different Water Conditions

In this experiment,water-soluble fertilizers with humic acid were sprayed on leaves to restore the effects of morphological and photosynthetic characteristics,mineral element accumulation,and nutrient quality on various parts of the plant by reducing drought,semi-arid,and semi-humid conditions.The effect of humic acid provides a theoretical basis for the study of the regulatory mechanism of humic acid on potato yield and quality.The main findings are as follows:1,under different water conditions,humic acid and water-soluble fertilizer to a certain extent increased the plant height,stem diameter and yield,the plant height increased by 3.07% to 14.29%,stem diameter increased by 2.53% to 12.41%,yield increased2.53%~36.18%,and the largest increase in drought conditions.Plant height increased by 3.07% ~ 14.29%,stem diameter increased by 2.53% ~ 12.41%.The humic acid water-soluble fertilizer had a significant effect on the photosynthetic characteristics of potato leaves.After spraying humic acid,the SPAD value of potato leaves increased by 1.84%-11.35% compared with the control,the photosynthetic rate increased by 4.49%-24.07%,and the transpiration rate decreased 2.34 %~17.69%,stomatal conductance decreased by 2.91%~15.04%,water use efficiency increased.The effect is different under different water conditions,and the best spraying effect is under the condition of drought.After treatment with humic acid,the nitrogen content in potato leaf increased by6.67%~51.52%,the nitrogen content in stem increased by 6.84%~102.77%,and the nitrogen content in root and tuber increased by 11.54%~52.78% and 10%~55.83,respectively.%.Under drought conditions,spraying humic acid increases the nitrogen content of roots and tubers better.4.Phosphorus content in potato leaves was increased by spraying water-soluble fertilizer with humic acid,and the increase ranged from 11.60% to 71.65%;phosphorus content in stem increased by 2.78% to 68.31%;and phosphorus content in roots and tubers increased by 0.018 over control.%~11.00%,0.33%~6.54%.Under drought conditions,the effect of humic acid treatment on the phosphorus content in stems and leaves was more obvious.Under different water conditions,potassium content in leaf and root increased by4.32%~25.40% after spraying humic acid treatment,potassium content in stem increased by 1.28%~29.51%,potassium content in root and tuber were The control increased by 5.63% to 59.09% and 4.53% to 81.82%.With the aggravation of drought stress and the advancement of growth period,the treatment of humic acid has more significant effect on the increase of potassium in tubers.The humic acid water-soluble fertilizer can improve the nutritional quality of potato tubers under different water conditions.The protein content in tubers increased by76.65%~89.72%,the sucrose content increased by 7.45%~17.37%,and the reducing sugar content increased by 40.76%~47.87%.The content of ascorbic acid increased by 8.33% to 16.67% and the starch content increased by 11.11% to 49.59.Spraying humic acid water-soluble fertilizer under different water conditions can increase the nutrient content of potato tubers and improve the nutritional quality of the potato.Spraying humic acid under the conditions of drought is the best.