| Insects are the largest biological resources today on the earth which haven't yet been fully utilized. Considering the fact that there are a great variety of insects and rich in natural resources of insects in China, it will undoubtedly produce good benefits on economy, society and ecology with a rational development and utilization of our country's insects resources. Tenebrio molitor is one of traditional feed and edibile insects in China. Not only there are large quantities of food sources to raise T. molitor, but also it has a short generation cycle and strong living ability. In addition, it is rich in nutritional ingredients, easy to raise and characterized by low feeding cost. It had been only used as feed stuff or bait for livestock, poultry and other special economic animals in the past, and nowadays it has been widely applied into agriculture, animal husbandry, food and medical care. So it has a high value for development and utilization and has a bright market future. Recently, the scale of the industry in breeding T. molitor has been increasing gradually and a new industry chain has emerged, in such provinces as Shangdong and Hebei, the core of which is raising and comprehensive utilization of T. molitor. However the quality of the varieties of T. molitor is degenerating, which has become the bottleneck restricting the further sustained and healthy development of the industry. Around the problem, the selection of varieties of T. molitor was studied. The growth and development traits, the reproductive capacity, the resistance to stress and the nutritional value of 2 kinds of color patterns of T. molitor were determined. The main stress-related isozymes of 2 kinds of color patterns of T. molitor were studied systematically. Furthermore, the preliminary researches on cloning and expression of the main stress-related genes of the 2 kinds of color patterns of T. molitor were carried out, too. The main results and conclusions were given as follows:1. The yellow and black color pattern of T. molitor with good genetic stability were obtained through natural selection of 12 continual generations.2. The black color pattern of T. molitor grew faster and more orderly than the the yellow color pattern. The black-color-pattern larvae of T. molitor went through 12-15 instars in all, while the yellow-color-pattern larvae went through 12-17 instars. But most of the yellow and black color pattern of larvae went through 14 instars. There were 27% larvae with 14 instars in the yellow-color-pattern and 53% in the black-color-patern. And the developmental duration of the black-color-pattern larvae was remarkably shorter than that of the yellow-color-pattern larvae. If taking the larvae with 14 instars into consideration, the developmental durations of the yellow and black color patterns of larvae were 154.3±7.9d and 134.1±3.2d respectively. In addition, the eggs and pupae developmental durations of the 2 kinds of color patterns of T. molitor were about 7d and 10d respectively. The hatching rate and pupation rate of the 2 kinds of color patterns of T. molitor were approximately 83% and 97%. The emergence rate of theirs were above 81%.3. There were no significant differences in each of the weight, growth rate and survival rate between the same days old larvae of 2 kinds of color patterns of T. molitor. But the yellow-color-pattern larvae had a significantly higher average food utilization efficiency than the black-color-pattern larvae of the same days. The average approximate digestibility, efficiency of converting digesting food and efficiency of converting ingested food(%) of the yellow-color-pattern larvae of T. molitor were 66.5±0.1,52.3±1.2 and 33.6±0.7 respectively, while those of the black-color-pattern larvae of the same days were 62.1±0.2,47.8±0.2 and 29.1±0.2 respectively.4. Under routine breeding conditions, the cumulative fecundity of the yellow-color-pattern female adults of T. molitor was obviously higher than that of the black-color-pattern female adults. But there was no significant difference in the sex ratio of the adults between the 2 kinds of color patterns of T. molitor. Under the same test conditions, the age at first egg, durations of oviposition and the daily variation of the fecundity of the yellow-color-pattern female adults were all basically the same as those of the black-color-pattern female adults. The statistical analyses showed that, under routine breeding conditions, the cumulative fecundity of the female adults of the yellow and black color pattern of T. molitor were 625.5±25.5eggs/female and 529.9±17.4eggs/female respectively. The female adults of the 2 kinds of color patterns were both 4 days after emergence when they were at first egg, and their oviposition peaks were both between the 14th and 44th day after emergence.5. There were significant differences both in heat resistance and cold resistance between the 2 kinds color patterns of T. molitor. The heat-resistance tests showed that the tolerance of the black-color-pattern larvae, pupae and adults to the high temperature (45℃) was stronger than that of the yellow-color-pattern larvae, pupae and adults of the same days. At the same time, the cold-resistance tests showed that the tolerance of the black-color-pattern larvae and pupae to the low temperature (-25℃) was stronger than that of the yellow-color-pattern larvae and pupae of the same days. But There was no significant difference between the tolerance of the adults of the 2 kinds of color patterns of T. molitor to the low temperature (-25℃).6. There was significant difference in the resistance to insecticides between the 2 kinds of color patterns of T. molitor. In the thesis, the Matrine pesticides of different concentration gradients were used to test the insecticides resistance of the larvae and adults of 2 kinds of color patterns of T. molitor. The results showed that the tolerance of the black-color-pattern larvae and adults to the Matrine pesticides was stronger than that of yellow-color-pattern larvae and adults of the same days. The LC50 values of Matrine insecticides against the 60-days-old larvae of the yellow and black color pattern were107.63mg·ML-1(72h) and 178.63 mg·ML-1(72h) respectively, while the LC50 values of Matrine pesticides against the 7-days-old adults of the yellow and black color pattern were 95.89 mg·ML-1(72h) and 162.54 mg·ML-1(72h) respectively.7. There was significant difference in the resistance to the pathogenic fator between the 2 kinds of color patterns of T. molitor, too. In this thesis, lipopolysaccharide (LPS) was used as the pathogenic fator to study the disease resistance of the 2 kinds of color patterns of T. molitor. The results showed that, after injecting 5μL LPS (0.5-2.0 mg·ML-1) solutions of the same concentrations, the survival rates of the black-color-pattern larvae, pupae and adults were significantly higher than those of the yellow-color-pattern larvae, pupae and adults of the same days. It was thus evident that the tolerance of black color pattern of T. molitor to LPS was stronger than that of the yellow-color-pattern.8. The analysis of nutritional components showed that the 2 kinds of color patterns of T. molitor have the high nutritional and utilization value since they are rich in nutrients. The protein contents of the larvae, pupae and adults of the 2 kinds of color patterns were about 48%-63% of their dry matter. They contained 18 kinds of amino acids, of which the essential amino acids occupied 48%-49%. Meanwhile, they are also rich in oleic acid, linoleic acid, linolenic acid and other unsaturated fatty acids and K, Na, Ca, Mg, Fe, Cu, Mn, Zn, Se and other minerals and trace elements. In addition, the nutritional composition of the 2 kinds of color patterns of T. molitor was characterized by that the yellow-color-pattern larvae and adults had the higher contents of crude protein, total amino acids and essential amino acids, whereas the black-color-pattern larvae, pupae and adults possesed a higher content of crude fat.9. The results of the main stress-related isozymes electrophoresis of the 2 kinds of color patterns of T. molitor showed that there were some similarities and differences in the isozymes zymograms between the yellow and black color pattern of T. molitor at the same developmental stages. Except there was no clear difference in the SOD isozyme zymograms between the 2 kinds of color patterns of T. molitor, there were obvious differeces in all the other isozymes zymograms,inciuding POD, EST, COD, MPO and DPO, between the yellow and black color pattern of T. molitor. Especially, there were so significant differences in each of EST, POD and MPO isozymes zymograms between the 2 kinds of color patterns of T. molitor that they might be considered as tool enzymes to classify the different varieties of the species.10. The determination of the main stress-related isozymes activities of the 2 kinds of color patterns of T. molitor of the same days showed that the activities of the most tested isozymes of the black color pattern were higher than those of the yellow color pattern under the routine rearing conditions. At the same time, Under each stress of the cold (-25℃), heat (45℃) and insecticides (Matrine), the protective enzymes and detoxification enzymes were mostly inhibited, whereas the defensive enzymes were activated. In addition, there were some differences both in the inhibition ratios of the same kind of protective and detoxification enzymes activities between the yellow and black color pattern of T. molitor under the above stress. And there were some differences in the growth rates of the same kind of defensive enzymes between the 2 kinds of color patterns of T. molitor under the above stress, too.11. The cloning and sequence analysis of the core fragments of some stress-related genes of the 2 kinds of color patterns of T. molitor showed that there was a high nucleotide sequence homology in each of the cytochrome oxidase subunit I(COI) cDNA, prophenoloxidase (PPO) cDNA and antifreeze protein(AFP) cDNA between the 2 kinds of color patterns of T. molitor. But there were still a few different nucleotides in each of the above core fragments between the yellow and black color pattern of T. molitor.12. The studies on the expression of HSP and AFP genes of the 2 kinds of color patterns of T. molitor larvae showed that, under the cold stress, the AFPmRNA expression of the black-color-pattern larvae had a significant up-regulation, whereas there was no visible increase in the AFPmRNA production of the-yellow-color-pattern larvae. At the same time, under the heat stress, the HSPmRNA expression of the black-color-pattern larvae had a significant up-regulation, whereas there was no visible increase in the HSPmRNA production of the yellow-color-pattern larvae. In addition, the response of the black-color-pattern larvae AFP to the testing cold-stress was significantly higher than that of the yellow-color-pattern larvae of the same days, and the response of the black-color-pattern larvae HSP to the testing heat-stress was obviously higher than that of the yellow-color-pattern larvae, too.
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