Evaluation Of Nutritional Components Of Natural Pasture And Quantitative Analysis Of Near Infrared Diffuse Reflectance Spectroscopy

Xilin Gol League grassland occupies a very important position in grazing as it is rich in forage resources and owns many kinds of natural forage species.In this study,grey incidence analysis theory was used to analyze the nutritional value of common natural herbage in Xilin Gol League grassland.Quantitative analysis of the feasibility of nutrient composition of natural pasture by near infrared spectroscopy(NIRS)was discussed.Experiment I: The common natural forage in this area are distinguished and identified.The contents of dry matter(DM),crude protein(CP),neutral detergent fiber(NDF),acid detergent fiber(ADF),acid detergent lignin(ADL),crude fat(EE),crude ash(Ash),calcium(Ca)and phosphorus(P)were identified and analyzed respectively.In the conventional nutrition evaluation method,the result of nutrition evaluation by a certain conventional nutritional index is often not comprehensive and accurate.In order to avoid this situation,grey incidence analysis theory is used to evaluate the nutrient composition of common natural grasses in Xilin Gol League grassland.The result of nutritional value from high to low order is : Phlomis>all-grass of Meadow Saussurea>Chenopodium acuminatum>Salsola collina Pall>Allium mong olicum Regel>Artemisia desertorum>Caragana microphylla Lam>Heteropappus altaicus(Willd)Novopokr>Corispermum hyssopifolium L>Potentilla bifurca Lin>lris l a c t e a l P a l l.Va r.c h i n e n s i s(F i s c h.)K o i d z > S t i p a B a i c a l e n s i s Roshev>Artemisiascoparia Waldst.et Kit>Artemisia frigida Willd.Sp.Pl>Leymus chinensis(Trin.)Tzvel>Serratula centauroides L>Manyroot Onion>Oenothera erythrosepala Borb>Cleistogenes squarrosa(Trin.)Keng>Artemisia argyi Levl>Salix cheilophila>Melissitus ruthenica>Krylov Needlegrass>Salix cheilophila>Ostryopsis davidiana Decaisne>Psammochloa villosa(Trin.)Bor>Stipa grandis P.Smirn>Agropyron cristatum(Linn.)Gaertn>Achnatherum splendens.Experiment II:In order to evaluate rapidly the nutrient composition of native grass by using near infrared reflectance spectroscopy(NIRS),a total of 407 samples of single and mixed forage grass were tested from May to November of Inner Mongolia Xilin Gol League grassland in 2016.This study utilizes the modified partial least squares(MPLS)to get the calibration of crude protein(CP),neutral detergent fiber(NDF),acid detergent fiber(ADF),acid detergent lignin(ADL),crude ash(Ash),crude fat(EE),calcium(Ca),phosphorus(P)by combing visible/near infrared reflectance full spectrum scanning technology with laboratory test data.The results show that the relative error of external verification(RPD(SD/SEP)of Ca,NDF,DM,CP and Ash is greater than 3,and the correlation coefficient RSQ between the value predicted by NIRS and chemical value is greater than 0.9,this indicates that calibration of Ca,NDF,DM,CP,Ash is good,the establishment of the calibration model can be used for practical detection;The relative error of external verification of ADF is 2.5<RPD<3,RSQ is 0.881,this indicates that the use of NIRS for the quantitative analysis of the components is feasible,but the accuracy needs to be further improved.The relative error of external verification of P,ADL,EE is RPD<2.5,RSQ is 0.56 0.472 and 0.806 respectively,this shows that the prediction model of P,ADL and EE can not be used in near infrared quantitative analysis.In this paper,the quantitative analysis model of the natural nutrient content of natural forage grass in Inner Mongolia area of Xilinguole Meng was established,which provided the basic data for the establishment of the natural nutrient value database.