Studies On Biological Characteristics Of Neospastis Simaona Wang In Mt.Meihua

Insect and plants are the most parts in the land biomes,which developed a special,complex and co-evolution relation. And the feeding reaction between phytophagous insects and their host plants always is a key issues of researching the relation between insects and plants. Most phytophagous insects feed plant leaves. Lepidoptera is the hot "zone" of researching insect action,because of large quantities. So researching lepidoptera ,especially larvae's feeding action,can help us understand the phytophagous insects' biological characteristics and the impact extent of plant,and provide theoretical basis for carrying out insect feeding and plants defense's research. This research is in Fujian Meihua Moutains,and selected the Neospastis simaona Wang and their host plants for the trial target .We raised the Neospastis simaona Wang larvae in the lab,and through the continuity and long-term obervation for the Neospastis simaona Wang, which results as follow:1. Their generation is 86～105days, average 91.1days.They ecdysis for five times during growth, which including 6 age period, the forth 4 ones is shorter. The duration of time a smaller, more orderly time, were five to nine days, six to 13 days, 6 to 10 days, 8 to 14 days. The later age 5 and 6 aging larvae development duration is longer, but their growth is not tidy. The duration are separately 9 to 25 days and 16 to 29 days. The duration of egg period is five to nine days, with an average of seven days. Adult female survival time is longer than adult male. Female survival duration is of 5 to 9days, and male adult survival duration is 4 to 6days.2. The biological characteristics of Neospastis simaona Wang are: 1) Mostly eggs are oval-shaped. At the beginning of production the eggs are the milky white,and exposed in the air after some time,which are gradually change color to light yellow green.2) Larvae are soft, with many inter-fold. Their body color is changing during development process. Newly hatched larvae are light green color, transparent crystal, and the head of light brown. With the growth of the larvae, their body color turn light yellow, and their back along the midline of the body carry out two light brown spots, and head has gradually turned into dark brown. The 5and6 Aging larvae's abdomen color is dark yellow. Two light brown spots back of the expanding scope to back into a dark brown, but only in the middle left a yellow area. Heads become completely dark brown.3) Pupae body length rage is 8.5 to 11.24 mm. First, the pupae are soft yellow, and which exposed to the air for some time, and they turn into brown, and finally turn into deep dark brown.4) Before adult emergencing, the insects' head reveal the pupa shell. 1days after the adults emerge and they stay one place for most time, and they often hid in the back of the leaves. Most adults mate in 2 to 4 pm. The duration is different, and the logest sustainable is nearly 1hour, and for the most parts are around 0.5hour.3. Larvae like feeding alone .They sticked out a lot of silk to make two leaves be a insect-shell and feeded leaves in insect-shell,after they sectioned their own "area". In the course of feeding,larvae immediately stopped feeding and quickly hided back the nest when they were frightened. After the larvae feeding,they would be back to the nest according to the original route,and filled the gap with excrement.4. The feeding preference research results of feeding larvae with 12 plants show that:larvae just feed Schima superba. With the test doing, its section index growly increases, from 7.15 added to 25.7.The larvae didn't feed the other kinds of plants at all, and which showed the antifeeding phenomenon.5. The research of larvae' feeding preference of Schima superba's young and old leaves in different age and the research of leaf hardness and total N content on the larvae feeding's impact show that: 1.With time growing, section index of feeding Schima superba's young and old leaves gradually increases. The range of section index was growly increasing from 3 age to 5 age,and then declined slightly. On the whole the duration trend was rising first,then fell.2.In the process of growth the trend of RGR and RI was the same, which dropped rapidly with the increase of the age;the trend of ECI and ECD showed declining first,then increaming;in the whole development period the trend of AD was relatively stable,but still showed a small trend of decreasing.6. Although as a whole, the relation between total N content of Schima superba and the food consumption of larvae was not obvious ,it was found that it was still a positive correlation between them from various sub-age. The relation between leaf hardness and food consumption was that when hardness increamed slowly, the food consumption increamed too,and when the hardness significantly increased in a very short time,the food consumption was a result of the rapid decline.