The Cadmium-enriched Differences Of Ramie Germplasms Of Dual-purpose Of Feed And Fiber Its Feeding Safety Evaluation

Cadmium has a strong toxic effect on human beings,animals and plants.It is the most serious pollution of heavy metals in farmland at present.The cadmium accumulation and tolerance have obvious differences in the different germplasm resources.In order to screen out the germplasm resources of forage ramie with high quality,high yield and low cadmium enrichment,the germplasm resources of fibrous ramie with high quality,high yield and high cadmium enrichment.With the silage technology of ramie by-product,to provide the theoretical and technical support for safe utilization of ramie under Cd stress.The differences of cadmium enrichment among forage and fibrous germplasm resources and the evaluation of feed safety were carried out in 2016-2017,the test is divided into the following two parts:Experiment 1:A total of 33 germplasms were used for field experiment with an average cadmium content of 3.94 mg/kg.By compared the agronomic traits,yield,quality and cadmium accumulation,the two kinds of forage and fibrous ramie were used for screening out the varieties of forage and fibrous ramie to be used safely,the results were as follows:1)Among the 33 forage germplasms,the yield of above-ground has a significant differences.Comprehensive analysis of four high yield and good quality low accumulation of forage ramie varieties in 33 forage ramie varieties:yushanma(113.87 kg/667m~2 dry matter production,enrichment factor is 0.54),wugangbaipizhong(dry matter yield of 102.27kg/667m~2,crude protein content is 22.80%,enrichment factor is 0.53),shitunma(dry matter yield of 137.47 kg/667m~2,crude protein content is 24.14%,enrichment factor is 0.45),wushanxianma(dry matter yield of 142.27 kg/667m~2,crude protein content of 22.81%,enrichment factor is 0.57);2)Among the 33 fibrous germplasms,the yield of above-ground has a significant differences.The produce of high yield and high quality fiber is as follows:yushanma(Fiber yield is 44.61 kg/667m~2,fiber count is 2651 m/g;enrichment factor is 0.87),xiangtanqingpijiama(Fiber yield is 64.50 kg/667m~2,fiber count is 2015 m/g;enrichment factor is 0.80),changshunshanma(Fiber yield is 30.13 kg/667m~2,fiber count is 2201 m/g;enrichment factor is 1.02),xianfengdayelv(Fiber yield is 30.53 kg/667m~2,fiber count is2555 m/g;enrichment factor is 0.84),xiangsixianjianyongyihao(Fiber yield is 36.97 kg/667m~2,fiber count is 2464 m/g;enrichment factor is 1.44).,chengbubendima(Fiber yield is42.76 kg/667m~2,fiber count is 2034 m/g;enrichment factor is 0.87).,zhongzhuyihao(Fiber yield is 31.86 kg/667m~2,fiber count is 2225 m/g;enrichment factor is 1.03).The highest cadmium accumulated is in the hemp shell,the lowest of the hemp leaves.The order of cadmium accumulation in different parts is as follows:barks>roots>stems>fibers>leaves.Ramie has a strong ability to transport and enrich heavy metal cadmium.There were significant differences in cadmium accumulation and transport between different cultivars,and Houpizhong 1(enrichment coefficient is 0.37,transport coefficient is 0.52)and Yushan Ma(enrichment coefficient is 0.54,transport coefficient is 0.61)have a low cadmium accumulation and transport capacity.Experiment 2:The ramie by-product as the materials,and the degree of compaction,additive and opening time were taken as variables.The treatment groups were as as follows:A.without additives,B.+2%sugar,C.+2%sugar,+0.3%salt,D.+2%sugar,+0.3%salt,+10%corn flour,E.+2%sugar,+0.3%salt,+0.1%lactic acid bacteria,F.+2%sugar,+0.3%salt,+10%corn powder,+0.1%lactic acid bacteria.The compaction was divided into two silage units:400kg/m~3 and 570kg/m~3.The evaluation of quality and determination of cadmium of silage ramie were measured at 60d,90d and 120d,and the results were as follows:1)The high water content of ramie in natural condition was not successful,under the condition of 570kg/m~3,the quality of the silage processing group was significantly higher than that under 400kg/m~3;Handle the 400kg/m~3 compaction,The fermentation quality of silage was best in(sugar,salt,corn flour and lactic acid bacteria).Handled the 570kg/m~3compaction,the additive group was significantly better than the other additives in reducing the pH value,NDF content and ADF content of silage,and the quality of silage was the best.The dry matter content was 25.45%,70.1%higher than that of the control group,and the crude protein content was 12.34%,which was 18.89%lower than that of the control group.NDF content of 31.75%,compared with the control group decreased by 34.9%,ADF content of 23.37%,compared with the control group decreased by 40.97%.2)In the evaluation of safety,the difference of cadmium content in each treatment group was significant,During the 60 days of storage,the E group and F group were significantly lower in cadmium than in the pre-silage,and the cadmium content was 0.79mg/kg and 0.83 mg/kg respectively,which decreased by 40.5%and 33.7%respectively.With the increase of ensiling time,the cadmium content of all treatments showed an upward trend.The cadmium content in A group increased from 1.11mg/kg to1.21mg/kg,the range of increase is 9.01%.The cadmium content in B group increased from1.04mg/kg to 1.23mg/kg,the range of increase is 15.44%.The cadmium content in C group increased from 0.99mg/kg to 1.14mg/kg,the range of increase is 15.15%.The cadmium content in D group increased from 1.02mg/kg to 1.26mg/kg,the range of increase is 23.52%.The cadmium content in E group increased from 0.79mg/kg to 1.10mg/kg,the range of increase is 39.24%.The cadmium content in F group increased from 0.83mg/kg to0.97mg/kg,the range of increase is 16,87%.Adding sugar,salt,and cornmeal silage(cadmium content in 0.76 mg/kg)was added to the cow's day grain by 0.681%.It could be ensure that the cadmium content in daily grain is no more than the permissible limit of cadmium content in our country's feed(less than 0.5 mg/kg).