Effects Of Regulated Deficit And Oxygation On The Growth Of Asparagus Officinalis L

Under the severe trend of increasing water shortage,developing water-saving crop cultivation is one of the most effective ways.Micro-environmental conditions of crop roots have an important impact on crop growth,especially the oxygen and water.Regulated deficit irrigation and oxygation can effectively reduce crop water consumption,improve water and fertilizer use efficiency and the quality of fruits and vegetables at the same time,which is also important for promoting the growth of aboveground and underground parts.In order to explore the effects of regulated deficit and oxygation on the growth of Asparagus,Asparagus was taken as the experimental material in pots,with full irrigation without oxygen(CK)as the control group,set four deficit-aeration treatments,deficit irrigation was conducted at seedling stage(YM),juvenile stage(YN),mature stage(CZ)and shoot harvest period(CS),respectively.each treatment was fully irrigated during the nonregulated period,and the upper limit of irrigation was FC.This test mainly explored the effects of regulated deficit and oxygation on Asparagus' morphological indexes,root growth,shoot yield,quality and water consumption.The results showed that:(1)The plant height and stem diameter of asparagus showed a trend of gradual increase with the advance of the growth period,which showed that the growth rate of asparagus was relatively slow in the seedling stage,rapid in the early growth stage and the mature stage,and the growth rate of asparagus tended to be flat in the shoot harvest stage.At the end of the growing period,the plant height and stem diameter of each treatment were compared,and it was found that the growth of plant height and stem diameter of asparagus could be improved by regulated deficit and aerated irrigation in the growing period,and the plant height and stem diameter of asparagus could be increased by 20.3% and 17.7% respectively.During the whole growth and development of asparagus,the changes of chlorophyll content in all treatments were basically the same,showing a single-peak growth trend and reaching the peak in the early childhood.The chlorophyll content of asparagus at the end of harvest period was observed.(2)By observing and comparing the characteristic indexes of root system under different treatments,it was found that deficit control and aeration irrigation during shoot harvest period could effectively promote the growth of root index,and could increase the total root surface area by 56.8%,average root diameter by 19.9%,total root volume by 39.0% and number of root tips by 39.5% compared with CK.At seedling stage,juvenile stage and mature stage,the root-crown ratio of asparagus increased by 49.2%,1.4% and 11%,respectively,compared with CK.At the end of the harvest period,the ratio of root to shoot was compared.It was found that CZ treatment> CS treatment> YM treatment> YN treatment> CK,CZ treatment increased by 10.3% compared with CK.From the seedling stage to the mature stage,root activity of the treatment with deficit control and oxygen enhancement increased by 9.6%,27.3% and 32.4%,respectively,compared with CK,with significant differences.Shoot of the treatment of root activity of YN > CZ > CS > YM > CK,strongest YN treatment root activity is 0.295 mg/(g·h),and the weakest was CK 0.213 mg/(g·h),processing root activity is YM,YN,CZ,CS,CK treatment increased by 6.5%,3.1%,4.2% and 38.5% respectively,deal with the root activity of 0.283 mg/(g·h),the CK 0.213 mg/(g·h)increased by 32.86%.(3)Comparing the yield of Asparagus,it was found that YN treatment>CZ treatment>YM treatment>CS treatment>CK treatment,the average yield of YN treatment was 770 g,which was 16.7% higher than that control group;the average yield of CZ treatment was 740 g.which was 12.1% higher than that control group;the average yield of YM treatment was 710 g,which was 7.6% higher than that control group;the average yield of CS treatment increased by 4.5% compared with the control group.Mild water deficit and rhizosphere oxygenation in early childhood can significantly improve the quality of young shoots of asparagus.Compared with CK,the content of protein,vitamin C and soluble sugar in young shoots of asparagus under YN treatment increased by 14.3%,12.0% and 31.5%,respectively.Compared with the control group,the total irrigation water used in treatment YM,YN,CZ and CS during the whole growth period was reduced by 1168 ml,2206 ml,1854 ml and 1384 ml,respectively.The water-saving rate was 4.3%,8.2%,6.9% and 5.1% respectively.