| Sphaeroderma apicale Baly was a newly found pest on mountain areas of Hubeiprovince. Through laboratory culturing and field investigation, we observed themorphological and biological characters and natural population dynamics, constructedlife table, and developed the strategies of chemical and emergency control ofSphaeroderma apicale Baly. The main results were listed below:Distribution, occurrence and harms:Sphaeroderma apicale Baly have been found in 3 cities of Hubei province.Larvae could mine into the leaves of corn, sorghum, sugar cane and some grassweedssuch as Setaria viridis (L.) Beauv and Coix lacryma-jobi L.which causes maindamage. Adults could also feed on the underside of elm leaves. The damage made bylarvae and adults on leaves may lead to leaf blast.Biological characters:The results showed that the beetles, which could overwinter as adults and pupae,had 1 or 2 incomplete overlapping generations per year in Yichang, Hubei. The adultswill emerge in mid-April and invade corn in early May. Emergency peaks areappeared on June 15th and August 7th. Field maximum amount of eggs and larvaewas found on Jun 18th and June 22nd, respectively.Life-table:We found that the natural population trend index (I) of S. apicale lab populationis 16.20, the average fecundity is 123.5 and the sex ratio is 0.491. In the prevailing,breaking out and coming down period, the percentage of S. apicale parasitoid byHemiptarsenus variconis are 14.46%, 33.6% and 77.0%, respectively.Pest Risk Analysis:The risk management for controlling Sphaeroderma apicale Baly shows thebeetles can be colonization and spread quickly after outbreaks in Hubei. All the resultswill benefit working out new regulations to control Sphaeroderma apicale Baly.Control Techniques:The best two chemical pesticides were 1000x diluted liquid of Ke Chong Xin andLorsban 4E, which could reach to 76.3% and 66.5% control effect; Eggs, first and second instar larvae were more sensitive to chemical medicaments than third instarlarvae.
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