Effects Of Water-saving Irrigation On Yield And Quality Of Silage In Hetao Area

The waste of agricultural irrigation water in our country is serious.Hetao area belongs to the northwest area.The irrigation technology is backward,and the proportion of water is seriously unbalanced.Hetao area is also a farming pastoral area,so silage corn planting has a very high application prospect.This study was carried out in YuanZiqu experimental station of Bayannur Academy of Agricultural and Animal Sciences.In 2018,"Qingzhu 808",a variety with higher biological yield and grain yield,was selected from 9 silage varieties participating in the water-saving irrigation test in 2019,and the contrast was "Dajingjiu 26".In the experiment of water-saving irrigation,four conditions were designed:full drip irrigation(FI),80%FI,60%FI,40%FI.The agronomic characters related to drought resistance,dry matter accumulation,grain yield and biological yield of each conditions were investigated.The results were as follows:1.Leaf area index,SPAD,number of green leaves,RPR,plant height,ear height and plant height uniformity are all affected by water stress to varying degrees.It is found that the relevant agronomic characters of stem and leaf can be used as the character index to determine the drought tolerance of silage varieties.2.The yield and yield components of "Qingzhu 808" and "Dajingjiu 26" were not significantly affected by water stress under mild water-saving condition,and the yield of"Qingzhu 808" under 80%FI treatment was slightly higher than that of FI treatment,which indicated that moderate water-saving could improve the yield of silage corn;under medium and heavy water-saving condition,the yield and yield components of the test species were significantly affected by water stress,indicating that the transition section water can significantly affect the grain yield and biological yield of silage;compared with the two varieties,"Qingzhu 808" is more sensitive to moderate and severe water stress,indicating that"Qingzhu 808" is more drought resistant than "Dajingjiu 26";the research results are consistent with the previous research results of agronomic characteristics.3.Through path analysis,it is found that the target of silage variety selection in Hetao area should be placed on plant height,leaf area index at maturity and leaf green retention,and in order to ensure the biological dry weight of silage,the dry weight of single ear should also be considered.4.Moderate water-saving can improve the nutritional quality of silage corn.It is unscientific to over water in actual production to improve the fresh weight of corn,especially when corn is used as silage feed,more attention should be paid to the nutritional quality.Under the condition of high water content,the content of NDF is higher and the proportion of components that are not easy to be digested within 240h is higher.Under the condition of medium and high water saving,the content of NDF is less and more NDF can be digested within 240h,and silage can obtain higher net energy of milk production under the condition of medium and high water saving.5.The medium and high water saving can improve the water use efficiency of irrigation,and the drought tolerance of "Dajingjiu 26" is stronger than that of "Qingzhu 808".However,in order to ensure the biological yield of silage corn and consider the variety quality at the same time,it is recommended that the cultivation mode of "Dajingjiu 26" and "Qingzhu 808"in Hetao area is drip irrigation under large and small film,and the irrigation volume in the whole growth period is 124 m3/Mu,and the biological output can reach about 5800 kg/Mu.Compared with the water consumption of full drip irrigation,it can save 31 m3/Mu,compared with the water consumption of Yellow River flood irrigation(farmer mode),it can save 156 m3/Mu.