Comprehensive Study On Production Performance And Nutritional Quality Of Different Agropyron Gaertn. Varieties

Agropyron Gaertn.is a perennial cross-pollinating plant of Triticeae in Gramineae,widely distributed in northern areas of arid grassland and desert in China.These Agropyron grass has high nutritional value,good palatability,high drought and cold tolerance,and can be used for dustproof and sand fixing.To choose good forage varieties suitable for improving grassland,sixteen Agropyron varieties（lines）were studied in this study.Three aspects,grass yield,seed yield and yield-correlated traits,and nutritional value in 2021 and 2022,were analyzed for the high yield and quality forage materials selection.This study would provide a scientific and theoretical basis for germplasm resource innovation,new variety development,and utilization of Agropyron grasses.The main findings are as follows.1.Comparing the 16 Agropyron varieties,the height of plants in 2021 ranged from 61.52-80.24 cm,with AZ1513 and Mongnong N0.1 having the highest plants at80.24 cm and 77.97 cm,respectively.The height of plants in 2022 ranged from38.67-57.47 cm,with Mengnong N0.1,Hycrest-Mengnong,and AZ1513 having the highest plants at 57.47 cm 54.93 cm and 52.53 cm,respectively.The varieties（lines）with higher average fresh grass yield were AZ1513(13595.00 kg·hm^-2),AZ879(11211.67 kg·hm^-2),and AZ1512(10500.00 kg·hm^-2);the varieties（lines）with higher average hay yield were AZ1513(4766.67 kg·hm^-2),AZ879(3666.67 kg·hm^-2)and A5(3505.00 kg·hm^-2).Cluster analysis of average fresh grass yield,average hay yield,and average plant height in two years showed that 16 materials were clustered into three categories,and AZ1513 as a separate category showed highest plant height and high forage yield.A5,AZ1267,Hycrest-Mengnong,A7,A3,Mongnong N0.1,AZ605,AZ1512,and AZ879 were grouped into one group,and the plant height and forage yield were better performance.The other materials were ordinary.2.The correlation analysis of forage seed yield and its components showed a significant positive correlation between seed yield,spike width,and panicle weight（p<0.01）.There was a significant positive correlation between spikelets per spike（p<0.05）and a negative correlation between the spike length and florets per spikelet（p<0.05）.Cluster analysis of seed yield and its components showed that 16 materials were divided into three categories.AZ605,AZ1513,and AZ879 were clustered into one category,showing the highest seed yield,the largest grains per spikelet,and the heaviest panicle weight.AZ1267 and Hycrest-Mengnong were clustered into one group,which showed that the seed yield was general,the spike width was the widest,and the spikelets per spike were the most.Other materials were clustered into one group,showing low seed yield,the longest spike length,and the most florets per spikelet.3.The quality characteristics of 16 Agropyron materials were studied.The varieties（lines）with higher average CP content were A7（22.05%）,A6（21.25%）,and AZ1512（20.88%）;the varieties with higher average EE content were AZ1267（6.47%）,AZ605（5.62%）and A6（5.56%）;the average content of Ash was higher in AZ605（10.72%）,A7（10.56%）and AZ1267（10.26%）;the moderate content of ADF was lower in A4（39.60%）,A8（45.47%）and A6（45.55%）;the average range of NDF was lower in A3（55.53%）,Hycrest-Mengnong（60.24%）,and A8（62.81%）;the higher P content was A6（0.47%）,AZ1513（0.46%）and Hycrest-Mengnong（0.44%）.The cluster analysis of the above indicators showed that AZ605,AZ1512,AZ879,AZ1267,A8,A6,AZ1513,and A4 had better nutritional quality.The ratios of essential amino acids to total amino acids（E/T values）of 16 Agropyron materials ranged from 37.23%to 44.30%;the SRC value of amino acid nutritional balance was between 72.00%and 94.85%,among which seven materials（A2,A5,A7,Hycrest-Mengnong,AZ879,AZ1267,and AZ1512）had an essential amino acid index greater than 0.95,all of which showed high-quality protein sources.4.The production performance and nutritional quality of 16 Agropyron materials were comprehensively evaluated by using grey relational degree analysis.The production performance and nutritional quality of Agropyron materials were evaluated according to the weighted relational degree.According to the sequence,AZ1513,AZ605 and A7 showed better comprehensive traits,while other Hycrest-Mengnong,AZ1267,AZ879,A6,AZ1512,A4 and A8 showed better comprehensive performance than Mongnong N0.1.These varieties could be used as potential excellent forage varieties in the future.