Evaluation Of Nutritional Value Of Whole Plant Corn In Different Planting Areas By FTIR Technique

The purpose of this test is to determine the correlation between the conventional nutrients,CNCPS components,rumen degradation rate and spectral parameters of whole plant corn in different planting areas（Beijing,Tianjin,Cangzhou,Urumqi,Dongfeng）,try to construct a regression equation between the two,in order to substitute the spectral parameters of the whole plant corn obtained by scanning the FTIR spectrometer into the regression equation to quickly and accurately predict the nutritional value of the whole plant corn.The whole plant corn samples needed for the experiment were collected from September to October 2017,and the harvest period was from late milk maturity to early wax maturity.The variety was Fengkenbainuo.Five points sampling method was used to cut 20 in each planting area,the stubble height is about 10 cm.The results showed:（1）Among the conventional nutrients,the CP content of the whole plant corn in Beijing was the highest at 8.75%;the EE content of the whole plant corn in Dongfeng was the highest at 4.98%;the Ash content of the whole plant corn in Urumqi was the highest at 5.83%;the NDF and ADF of the whole plant corn in Cangzhou were the highest at 53.67%and 27.76%.Among the CNCPS components,the PC content of the whole plant corn in Beijing was the highest at 7.99%,and in Tianjin was the lowest at 4.24%;the CC content of the whole plant corn in Beijing was the highest at 11.51%,and in Dongfeng was lowest at 6.43%.Among the rumen degradation rate,the DM_EDand NDF_ED contents of the whole plant corn in Cangzhou were the highest at 53.36%and 39.75%;the CP_ED content of the whole plant corn in Beijing was the highest at 54.19%.（2）There was a significant correlation between the CP content of the whole plant corn and the A＿AmideⅠ、A＿AmideⅠ/AmideⅡratio、H＿AmideⅠ、H＿AmideⅠ/AmideⅡratio、H＿β-sheet、H＿α-helix/β-sheet ratio in the spectral parameters（|r|=0.70～0.52,P<0.05）.There was a significant correlation between PC content and H＿α-helix（|r|=0.55,P<0.05）.There was a significant correlation between DM_ED content and A＿AmideⅠ、A＿AmideⅡ、H＿AmideⅠ、H＿α-helix、H＿β-sheet（|r|=0.76～0.56,P<0.05）.There was a significant correlation between CP_ED content and A＿AmideⅠ、H＿AmideⅠ、H＿AmideⅠ/AmideⅡratio、H＿β-sheet（|r|=0.68～0.59,P<0.05）.（3）The content of protein nutrients,CNCPS protein components,DM and CP rumen degradation rate could be predicted by the whole plant protein spectral parameters.H＿α-helix could be used as a predictor to predict ADICP content in whole plant corn（R²=0.62）,H＿AmideⅠ/AmideⅡratio could be used as a predictor to predict PA content in whole plant corn（R²=0.59）,A＿AmideⅠ/AmideⅡratio could be used as a predictor for the whole plant corn DM_c（R²=0.55）,and A＿AmideⅡcould be used as a predictor for the whole plant corn CP_c（R²=0.63）.（4）There was a significant correlation between the NDF content of the whole plant corn and H＿1162/H＿1111、H＿1162/H＿1052、H＿1111/H＿1052 in the spectral parameters（|r|=0.59～0.54,P<0.05）.There was a significant correlation between CC content and A-STCHO（|r|=0.64,P<0.05）.There was a significant correlation between NDF_ED content and A-STCHO、A-STCHO/A-CHO、H＿1162/H＿1052（|r|=0.75～0.55,P<0.05）.（5）The content of carbohydrate nutrients,CNCPS carbohydrate components,and NDF rumen degradation rate could be predicted by whole plant corn carbohydrate spectral parameters.H＿1162/H＿1052 could be used as predictors to predict the NFC content of whole plant corn（R²=0.86）,A-STCHO could be used as predictors to predict the CB₁ content of whole plant corn（R²=0.59）,H＿1162/H＿1111 and H＿1111/H＿1052 could be used as predictors together,they were used as predictors to predict the NDF_b content of whole plant corn（R²=0.71）.To sum up:there is a correlation between the conventional nutrient composition,CNCPS composition,rumen degradation parameters and spectral parameters of whole plant corn in different planting areas,and a regression equation can be constructed between the two.With the help of spectral parameters,the nutritional value of the whole plant corn can be predicted quickly,accurately and non-destructively.