Effects Of Slow Release Fertilizer Instead Of Chemical Fertilizer On Growth Physiology,Quality,Nutrient Absorption And Soil Enzyme Activity Of Garlic Seedlings

In response to the excessive application of chemical fertilizers in the production process of garlic seedlings after autumn delay,resulting in the reduction of garlic seedlings quality,yield,fertilizer utilization rate,soil nutrient imbalance,and soil enzyme activity,etc.slow-release fertilizers were used instead of ordinary fertilizers to reduce the amount of fertilizers.purple garlic was used as the test material,and the fertilizer application test of garlic seedlings after autumn extension was conducted in Wushan area.The experiment adopts a random block design and sets 5 treatments:no fertilization（CK）,local ordinary fertilizer constant fertilization（CK1,N、P、K,f ertilization amount144.9 kg/667m²）,ordinary fertilizer reduction fertilization（T1,total nutrients reduced by 47.8%compared with CK1）,slow-release fertilizer reduced fertilization（T2,the amount of fertilization is the same as T1）,slow-release fertilizer constant fertilization（T3,the amount of fertilization is the same as CK1）,to study the growth physiology,quality,photosynthetic characteristics,yield,nutrients of garlic seedlings under different fertilization treatments using the effects of absorption and related enzyme activities,the feasibility of using slow-release fertilizers to replace ordinary chemical fertilizers to reduce the amount of chemical fertilizers was explored to provide a theoretical basis for the rational fertilization of garlic seedlings.The main research results have the following five aspects:1.Compared with local constant fertilization（CK1）,T2 and T3 treatments can significantly increased garlic seedling growth,root activity and nitrate reductase activity of leaves.Compared with CK1,T2 and T3 increased the stem thickness of garlic seedlings by 29.6%and 21.2%,respectively,and the leaf width increased by17.9%and 22.1%,respectively.There was no significant difference in plant height and stem thickness;root activity increased by 62.7%and 29.8%;leaves Nitrate reductase activity increased by 18.1%and 14.7%;chlorophyll a+b content increased by 97.9%and 129.4%.Compared with T3,the root activity and nitrate reductase activity of garlic seedlings treated with T2 were significantly increased,increasing by28.4%and 14.8%,respectively,while there was no significant difference in stem length,leaf width,stem thickness,plant height and chlorophyll content.2.Compared with CK1 treatment,T2 treatment significantly increased the absorption of nitrogen,phosphorus,and potassium of garlic seedlings by 19.7%,17.5%,and 12.3%,respectively,and significantly reduced the soil nitrogen,phosphorus,and potassium surplus.The nitrogen,phosphorus,and potassium absorption of garlic seedlings treated with T3 increased by 9.1%,7.2%,and 10.1%compared with CK1,respectively,and the surplus of soil nitrogen,phosphorus,and potassium decreased significantly.The utilization rate of nitrogen,phosphorus and potassium fertilizers in T2 treatment increased by 15.5,12.7 and 10.2 percentage points respectively;the utilization rate of nitrogen,phosphorus and potassium fertilizers in T3 treatment increased by 2.4,1.6 and 5.1 percentage points respectively.3.Compared with CK1 treatment,the output of T1,T2 and T3 treatments increased by 2.1%,4.1%and 3.9%respectively.The input-output ratios of CK1^T3treatment are 1:3.6,1:4.0,1:4.1,and 1:3.8,respectively.In contrast,T2 treatment can improve the economic benefit of garlic seedlings in the season,with the highest input-output ratio.4.Compared with CK1 treatment,T2 and T3 treatments can significantly increase the content of vitamin C,soluble protein and soluble sugar in garlic seedlings,and significantly reduce the contents of garlic seedlings nitrate and crude fiber.Compared with CK1,the content of vitamin C,soluble protein,and soluble sugar in T2 increased by 78.2%,12.6%,and 84.2%,respectively.The content of nitrate and crude fiber decreased by 25.5%and 44.7%,respectively.There was no significant difference in allicin content.5.Compared with CK1 treatment,T2 treatment can significantly increase the soil available nutrient content and soil enzyme activity in the root system of garlic seedlings.The cellulase,urease and sucrase activities of T2 increased by 47.7%,28.5%and 18.1%respectively compared with CK1;the content of alkali-decomposed nitrogen increased by 16.5%,and the contents of available phosphorus and available potassium increased by 17.1%and 7.1%,respectively;The organic matter content increased by 19.3%.6.Compared with CK1 treatment,there was no significant difference in the plant height,stem thickness,leaf width,stem length and nitrate reductase activity of garlic seedlings treated by T1 treatment;the chlorophyll content and root activity were significantly increased by 66.2%and 43.4%,respectively.Nitrogen,phosphorus,and potassium fertilizer utilization rates increased by 10.4%,15.3%,and 7.9%,respectively;vitamin C,soluble protein,and soluble sugar content increased significantly,by 70.7%,8.9%,and 67.3%,respectively,and nitrate and crude fiber content were significantly increased decreased;there was no significant difference in soil invertase,cellulase activity and allicin content.In summary,the reduction of ordinary fertilizer application（T1,total nutrients reduction of 47.8%,N reduction of 40%,P₂O₅ reduction of 88.4%,K₂O reduction of16%）can reduce agricultural input and increase fertilizer in actual production.Utilization rate and output improve quality.The use of slow-release fertilizer reduction fertilizer（T2,the same amount of fertilizer as T1）to replace ordinary chemical fertilizer has the best economic benefit and the highest input-output ratio.It can increase production,increase production,reduce production cost and increase soil-related enzyme activity.Improve quality while increasing fertilizer utilization.