| The present thesis which included the biology and artificial rearing of Carabus formosus nili,and the population were achieved successfully on combined field with laboratory for the first time at Yangling, Shaanxi province.Carabus formosus nili belongs to Coleoptera, Adephaga, Carabidae, Carabus .The adults and larvae are both predaceous, the adults prey on snail, land slug, earthworm and Many kinds of Lepidoptera larva like Pieris rapae (L.), Mythimna separate (Walker), Prodenia litura (Fabr.) and so on. The larvae mainly prey on snail. It's an important natural enemy insect resource. And they are always be made into handicraft articles, artificial amber due to the large body shape with brown or blue violet metal luster, so they are important resource with ornamental value. In this experiment, biology and artificial breeding skills were studied, which could be the basis of artificial rearing and developing resources value. The results are as follows:1. Biology of Carabus formosus niliIt had two generations one year and adults overwintered in the soil in Yangling, Shaanxi Province. The adults occurred from late April to late October, oviposited in late May to late June and late August to late September. The developmental threshold temperature of egg was 10.33℃, its effective accumulated temperature was 132.86 degree-day. At 25℃, the egg stage lasted 7～9 days; the larval stage had two instars, the first instar was 4～6 days, the second instar 14～18 days; the prepupal stage lasted 16～19 days; the pupal stage lasted 7～10 days. The adults fed on snail, land slug, earthworm and Many kinds of Lepidoptera larva, the larvae mainly fed on snail.2. Artificial rearing skills of Carabus formosus nili(1) Selection of characters of preyTending to soft body wall, especially with wound.(2) The effects of temperature on feeding amountDaily average feeding amount at 25℃and 30℃level were 1.28 heads and 1.36 heads respectively, at 20℃and 35℃was 0.72 and 0.58 respectively, the difference is significant. It showed that 25℃～30℃was the suitable temperature for feeding.(3) The effects of air humidity on feeding amountAir humidity at 50%, 65% and 80% level, the daily average feeding amount was 1.1 heads, 1.28 heads and 0.98 heads respectively, the difference is not significant. It showed that air humidity didn't have much effect on feeding amount.(4) The effects of soil humidity on feeding amountDaily average feeding amount at 10% and 15% level of soil humidity were 1.28 heads and 1.17 heads respectively, at 5% was only 0.65 head, the difference is significant. It showed that 10%～15% was the suitable soil humidity for feeding.(5) The effects of different food on ovipositingThe egg laying rate was the largest 70% by Fed with snail, the average egg-laying amount per female was 7.1. Fed with flour weevil and locust abdomen, the percentage of ovipositing females was both 60%, the average egg-laying amount per female were 5.5 and 6.3 respectively, the difference is not significant. Fed with armyworm, the percentage of ovipositing females was only 40%, the average egg-laying amount per female was only 4.3, and the difference is significant. It showed that snail, flour weevil and locust abdomen were the suitable food.(6) The effects of soil humidity on survival rate of overwinteringThe survival rate of overwintering increased along with the increase of soil humidity, it reached maximum at 10% level, while at 20% level it reduced gradually.(7) Management measuresIncluding feeding reasonably, clearing residue of food, preventing and controlling parasitical acarid.
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