Transabdominal Transformation Of Tenebrio Molitor From Straw And Comprehensive Utilization Of Residue

Large quantities of crop straw produced annually are not effectively used every year nationwide,however,most of the them are burned or abandoned,causing serious environmental pollution and waste of resources.Tenebrio molitor,an important insect produced industrially,has been gradually achieved in standardized,specialized,large-scale and efficient breeding pattern in China,but its further development is seriously limited by the high feed cost.In addition,with the rapid development of Tenebrio molitor breeding industry,a large amount of aquaculture waste will also bring environmental pollution.China is a large agricultural country.It is an important way to transform breeding waste into organic fertilizer so as to alleviate the urgent need for fertilizer and it is also greatly significant to promote the sustainable development of agriculture.On the other hand,attention to reduce the efficiency of organic fertilizer and to pollute the ecological environment is developed due to the much loss of nitrogen species during the composting process.In this research,the feasibility to feed Tenebrio molitor larvae with silage corn stalk or sweet potato straw was explored initially.And different kinds of compound feed derived from conventional feed of Tenebrio molitor,silage corn stalk and silage sweet potato straw were designed by extreme vertex mixing design method,and the optimal feed formulation was sieved by determination of the effects of the feed formulation on the growth indexes(biomass increment rate,mortality,feed utilization rate and conversion rate).After the Tenebrio molitor was fed with the straw feed formulation,the residue in the process of breed was converted into organic fertilizer.On basis of loss of nitrogen during the composting process,the effect on nitrogen conservation of common metal powder(Al,Zn,Fe,Cu powder)in the process of composting was studied,aimingto reduce the loss of nitrogen during the composting process while turn feeding residue of Tenebrio molitor into organic fertilizer.The major results are as follows:(1)The quality grade of both silage corn stalk and silage sweet potato straw were superior grade.However,the growth and development of Tenebrio molitor larvae could not be satisfied by feeding only silage straws.(2)Based on mixing design method,analysis of data,optimizing and validating feed formulation,the optimal feed formulation of Tenebrio molitor was as follows:conventional feed: fermented corn stalk: fermented sweet potato straw=38.93:12.78:48.29.Compared with the conventional feed formulation,the feed cost of the optimal feed formulation was decreased by 57.50%.The biomass increment rate of Tenebrio molitor larvae reared with the optimal feed formulation reached 33.74%,advantageous over one reared with the conventional feed(25.31%).Moreover,the mortality rate of Tenebrio molitor larvae reared with the optimal feed formulation was low and the utilization of crop straw feed was high.(3)Adding 2% Cu powder or Zn powder to the compost showed significant effect on nitrogen conservation,which reduce the loss of nitrogen by more than 55%.When addition of mixed metal powder is 2%,Zn-Fe combination showed maximum effect on nitrogen conservation,to reduce the loss of nitrogen by approximate 50%;when addition of metal powder is 1% or 2%,the effect on nitrogen conservation of single Cu powder is better than other metal powder,and the effect on nitrogen conservation of 2%Cu powder is the most significant.(4)In the composting process,a small amount of metal powder can reduce the loss of nitrogen but has no effect on quality of organic fertilizer.The organic fertilizer derived from the breeding residue of Tenebrio molitor is completely decomposed and not poisonous.The results measured by the local fertilizer testing station showed that the technical indicators of the sample were better than the national standard,and it was a high-quality organic fertilizer product.In summary,the straw feed formulation,which was used as the feed of Tenebrio molitor,not only raise the utilization rate of crop straw,but also reduce the feed cost of Tenebrio molitor,so the formulation is of great prospective.Addition of 2% Cu powderinto the compost had significant effect on nitrogen conservation,which could turn the breeding residue of Tenebrio molitor into a high-quality organic fertilizer product.