Comparison Of Feeding Quality Of Different Maize Types And Breeding Of Waxy Maize For Silage

Silage maize is an important source of roughage for ruminants.Breeding new varieties,innovating germplasm resources,and adjusting breeding targets of silage maize are the most effective technological measures to ameliorate the crude production of ruminant animal and improve aquaculture efficiency in China.In this experiment,waxy maize(Jingkenuo 2000,Heinuo 1,Heinuo 191),foodstuff type maize(Zhengdan 958,Xianyu 335,Xundan 20),silage type maize(Beiqing 210,Quchen 9,50096×50923)were used as materials,to study the accumulation of biological yield,dry matter yield and the whole plant moisture content of different maize types after pollination.We measured the content of crude protein,ether extract,NDF and ADF,and used RFV and GI to analyze the comprehensive quality of ensilage.Seven combinations of waxy corn(51412×50923),(50258×50923),(40977×50923),(50512×50923),(50331×50923),(40533×50923),(50100×50923)were screened as test materials,and silage type maize(Beiqing 210)was used as CK.Randomized complete block experimental design was used in the trial.The yield and comprehensive quality of each combination were compared to screen new strains of waxy maize for silage which are suitable for planting in the northwest region.The conclusions of this study are as follows:1.Combined with the biological yield,dry matter yield and the whole plant moisture content,we determined 42 days after pollination as a suitable harvest period.The results showed that three types of maize were all in the 1/4 to 3/4 ML at harvest time.This provides a clear indicator for the harvest time of silage corn.2.The forage quality of waxy maize is better than foodstuff type maize and silage type maize,it's more suitable for silage.It is difficult to judge the quality of silage nutrition from a single nutrition index.Our study used relative feed value(RFV)and grading index(GI)to comprehensively analyze the roughage quality of different types maize.The results RFV classification showed that the RFV index of three types maize were above 151%,all of them were special grade.The results of GI classification showed that the GI of the silage in three kinds of waxy maize were all at stage 2.Among the three kinds of foodstuff type maize,Zhengdan 958belonged to grade 3,Xundan 20 and Xianyu 335 belonged to grade 2.Among the three kinds of silage type maize,Quchen 9 belonged to grade 3,Beiqing 210 and 50096×50923 belonged to grade 2.The classification results of GI are more accurate than RFV.And the result indicates that the feed value of waxy corn silage was better than foodstuff type maize and silage type maize,which can be used to make silage.3.In this experiment,the correlation analysis and path analysis were used to check the plant height,ear height,stem diameter,length of ear leaf,width of ear leaf,number of leaves and green leaves at harvest,stem weight,leaf weight,ear weight and biological yield of different types of maize.The results showed that the ear height is the key factor agronomic trait affecting biological yield of waxy maize.The length of ear leaf,plant height,stem diameter,stem weight are the key factor agronomic traits affecting biological yield of foodstuff type maize.The ear weight,stem weight,leaf weight,plant height and number of leaves and green leaves at harvest are the key factor agronomic traits affecting biological yield of silage type maize.4.The breeding strategy of different types maize for silage with high yield and qualityBreeding of waxy maize should coordinate the relationship between ear height and NDF content.The selection of foodstuff type maize should coordinate the relationship between length of ear leaf,plant height and stem diameter and NDF content;the selection of silage type maize should coordinate the relationship between the stem weight,leaf weight,ear weight and the content of NDF and ADF.5.The combination(50512×50923)was selected as a new line of waxy corn for silage,its biological yield(71.15 t/hm~2),dry matter weight(23.72 t/hm~2)and forage quality(GI was19.89MJ,belonged to grade 2)are better than CK.It is expected to become a good strain of waxy maize for silage.