Screening Of Germplasm Resources Of High-yield And High-quality Forage Oats In Southwest

The agronomic characters(plant height,fresh weight,total tiller,effective tiller)of 126 oats germplasm resources from wild oats in Israel,cultivated oats from Italy and China were measured in this study.The materials with higher agronomic characters were screened as core resources.The nutritive value(ash,crude protein,ether extract,water soluble carbohydrates,phytate,phosphorus,total phosphorus,total kalium,crude fiber,neutral detergent fiber and acid detergent fiber)of 21 oat resources was measured in three planting years(2018-2020),three planting areas(Chengdu,Ganzi,Guiyang)and three cutting stage(heading,filling,and mature stage).Anova,correlation network and principal component analysis were used for the analysis of effects of environment on the nutritive value of oat,the determine of the optimal cutting stage,and the screen of new and excellent forage varieties.The results would provide gene accessions and feasible measures for increasing the germplasm resources of forage in China and developing high-quality forage oats.The main conclusions of the studies are as follows:1.Total of 21 high agronomic characters oat germplasm resources were screened out from 126 wild and cultivated oat germplasm resources.The high agronomic characters germplasm resources were A01,A06,A07,R13,R06,R09,E01,E12,E13,N01,N10,N02,S18,T11,T02,T07,H03,H33,H60,L03 and L93,respectively.2.In the three-point experiments for three years,the variation coefficients of ash and phosphorus concentrations in nutritive value ranged 1.03-3.00 and 1.05-4.04,and the concentrations of ash and phosphorus were 7.50%-8.28% and 3.38mg/g-7.89mg/g.The differences were not significant and stable(P>0.05),which was greatly affected by genetic factors and was easy to be selected in breeding.For the crude protein,neutral detergent fiber,and acid detergent fiber,the coefficients of variations of the concentrations ranged12.42-19.72,7.09-11.77,and 5.83-14.41,which indicated high degree of dispersion,and the concentrations were 6.92%-13.06%,25.94%-30.81%,and 4.87%-6.94%,with significant differences(P<0.05),which were greatly affected by environmental factors.Therefore,selection standards should be relaxed in breeding.3.From heading stage to maturity stage,the concentrations of ash,ether extract,crude protein,water soluble carbohydrates,total phosphorus,and total kalium were 8.29%-8.13%,7.91%-7.83%,13.36%-9.87%,19.06%-10.2%,0.30%-0.22%,2.82%-2.02%,respectively.Therefore,according to the analysis of relative feed value(299.93-276.83)and relative forage quality(290.87-268.4),the optimum cutting stage of whole oat plant for forage was heading stage.4.The stable relative relationships among feed value and nutrient components in multi-point and years experiments were as follows: the relative feed value was negatively correlated with neutral detergent fiber,acid detergent fiber,crude fiber,ash,and phytate concentration,respectively,while positively correlated with the relative forage quality,total digestible nutrient,digestible dry matter,and dry matter intake,respectively.Among the nutrient components concentrations,phytate and phosphorus,total phosphorus and total potassium,water soluble carbohydrates and ether extract,neutral detergent fiber and ash,acid detergent fiber and ether extract,water soluble carbohydrates and crude protein were positively correlated,respectively,while water soluble carbohydrates and ether extract were negatively correlated.5.The evaluation of the nutritional composition of 21 oat germplasm resources found that the high-quality feed oats were all from Israeli wild materials.The high-protein germplasm resource is R09.The germplasm resources of high water soluble carbohydrates and high mineral elements are R09 and E12.High ether extract germplasm resources are N02 and E12.The high-phosphorus germplasm resource is R06.In terms of comprehensive feeding value,germplasm resources suitable for promotion are R09 and E12.