| In this experiment, newly hatched Hepialus sp. larvae and the third instar larvae choosing food from plant materials were studied by direct observation from July in the year 2010 to the next July, in manually controlled temperature room in Kangding Enwei Company. The feeding habit of newly hatched larvae about different parts of the same plant was also investigated. Three kinds of plant materials were fed to Hepialus sp. larvae after being mixed proportionally. Body weight, length, head capsule width and livability of Hepialus sp. larvae were investigated to screen the compound feed, which was suitable for Hepialus sp. larvae. Besides, nutritional components in three kinds of natural feed materials and the Hepialus larvae fed by these materials were analyzed.1. As the feeding was the main standard, the five plants preferred by newly hatched Hepialus larvae among the thirteen kinds of plant materials were feed material 9, feed material 2, feed material 11, feed material 1, feed material 3. The newly hatched Hepialus sp. larvae only fed a little or stayed transiently, without feeding, on other materials. Different from the preference order for the the newly hatched Hepialus sp. larvae feed, the third instar larvae were likely to prefer feed material 11, feed material 2, feed material 3, feed material 1, feed material 9, feed material 14 (cultivated species), feed material 15 (cultivated species) in turn.According to investigating newly hatched larvae’s feeding habit about different parts of the same plant, we found that they did not only preferred tender roots of plants, but also could feed on the stem (or the petiole), blade. Moreover, there was a preference order for these materials. The number of Hepialus sp. larvae choosing the rhizome of feed material 11 was the most, next came tuberous roots of feed material 3 and then the rhizome of feed material 2, the blade of feed material 11 and the stem of the feed material 9.2. After feeding Hepialus sp. larvae by three kinds of plant materials, which had been mixed into seven treatments proportionally, Hepialus sp. larvae livability in the third, the fifth, the sixth and the seventh treatments were higher than other treatments, the livability of Hepialus sp. larvae was the highest in the fifth treatment, which was 43.50%, and the livability of Hepialus sp. larvae in the first treatment was the lowest, which was only 15.75%.The body length in the fifth treatment grew most rapidly, followed by the third treatment, and the growing rapid in the second treatment was the lowest.However, the head capsule width in the third treatment was significantly higher than other treatments, indicating that larvae bodies were bigger on an average in the treatment. And the head capsule width in the second treatment was lower than other treatments, with extremely significant difference. In the metaphase investigation (from the third investigation to the fourth one), the head capsule width in the first treatment, the fourth treatment and the seventh treatment decreased, indicating that there were smaller larvae left, and several bigger ones died during this period.Besides, the third, the fifth and the seventh treatments were good for the larvae to increase body weight, significantly higher than other treatments.According comprehensive analysis of the seven treatments, the third, the fifth and the seventh treatments were suitable for the larvae, and the feed in the second treatment was the poorest for the larvae.3. It was found that the pupation rate of Hepialus sp. larvae was different in different treatment after the determination of the conformation characters of Hepialus chrysalides in each treatment (except treatment 2) by the end of the experiment. The pupation rate of the fifth treatment was 4.5%, the highest of all these treatments, which indicated that the larval stage might be shorter. The pupation rate of the sixth treatment was only 0.5%. And no pupae were found in the second treatment. However, there was no significant difference in pupa length and weight, which indicated that plant materials affected the time of larvae.4. There were abundant nutritional components in Hepialus sp. larvae. The crude protein content was different, and the declined trend of the crude protein content was the second treatment (33.3087%), the third treatment (31.8975%), the seventh treatment (30.7792%), the first treatment (28.8631%), the fifth treatment (28.2195%), the sixth treatment (27.7390%) and the fourth treatment (24.6059%). The Hepialus sp. larvae in the third treatment had the maximum content of crude fat (42.3528%), followed by the first treatment (36.3328%), and it was minimal in the second treatment, which was only 23.2602%. The soluble sugar content in the second treatment was significantly higher than other treatments (P<0.05). There was the highest water content in the second treatment, which was 83.0490%, and was significantly different from other treatments (P<0.05). The water content in the fifth treatment was the lowest, only 61.6146%.Mineral elements in larvae were determined, and the results showed that the content of K (41.8933 mg/g-52.1112 mg/g) was highest and the content of P (0.0099 mg/g-0.0285 mg/g) was the lowest among these treatments. The content of K in the first treatment was 52.1112 mg/g, significantly higher than that in other treatments (P<0.05). And there was no significant difference between the third treatment and the fifth treatment, the fifth treatment and the seventh treatment, the seventh treatment and the second treatment in the content of K. The content of P in the third treatment was 0.0285 mg/g, significantly higher than that in other treatments (P<0.05), which was 2.87 times of that in the sixth treatment. The content of Mg in the second treatment was the highest. The content of Fe in these treatments was extremely different, except the fourth and the fifth treatment. The content of Ca in the sixth treatment was 0.4674 mg/g, higher than other treatments. And the content of Ca in the first treatment was the lowest, of which the average was only 0.2675 mg/g.5. Nutritional components in the tuber of feed material 1, rhizome of feed material 2, and tuberous roots of feed material 3 were analyzed. The results showed that there were comparatively abundant nutritional components in all materials, such as dissoluble protein, crude fat and moisture. The content of dissoluble protein in feed material 3 tuberous roots was 10.5592%, which was about 2.4 times of that in the rhizome of feed material 2 and was the highest among the materials. The rhizome of feed material 2 had the maximum content of crude fat, which is 3.1488%. The content of dissoluble sugar in feed material 1 tuber was the highest (12.5268%), followed by tuberous roots of feed material 3 (6.7054%) and the rhizome of feed material 2 (3.6400%). The content of starch in the rhizome of feed material 2 was the highest (4.3719%), followed by that in tuberous roots of feed material 3 (2.2451%) and tuber of feed material 1 (0.3211%). In addition, there were also abundant mineral elements in these materials. More Fe, Mn, Mg, Cu, Zn were contained in the rhizome of feed material 2, and available K, Ca were found in tuberous roots of feed material 3. There was the highest element P in the tuber of feed material 1. |
PDF Full Text Request