Note: A new pest,Liriomyza trifolii, on cotton in the Büyük Menderes Valley, Turkey
The study was conducted to evaluateLiriomyza trifolii (Burgess) in the cotton fields of the Büyük Menderes Valley, Turkey, from 1999 to 2000. Leaves were sampled weekly from the middle of June to the middle of August and kept in the laboratory to observe emerging leafminers. Leafminers were initially found on cotton leaves from 35 to 66 days after sowing. The numbers of larval mines varied from one to four per leaf. The largest number of infested leaves was observed in Aydın (Center), where 18.8% and 17.7% of the sampled leaves were infested in 1999 and 2000, respectively. We conclude thatL. trifolii is a potential pest in the cotton fields of Turkey and more research is needed.
Agromyzidae (Diptera) in Thailand: new species, revisionary notes and new records
Six new species are described:Melanagromyza erawanensis sp nov.Melanagromyza inthanonensis sp.nov.,Melanagromyza pasiae sp.nov., andMelanagromyza pasiensis sp.nov.;Tropicomyia pilosa sp.nov; andPseudonapomyza rampae sp.nov. Two new synonyms are established in the genusCerodontha, subg.Icteromyza-hirsuta Sasakawa withpiliseta (Becker) andhardyi Sasakawa withduplicata Spencer,Phytagromyza santokhi Garg from India is synonymised withPseudonapomyza atrata (Malloch).Cerodontha rishii Garg from India is resurrected from synonymy. Fourteen species are now recorded as new to Thailand, making the total now to 27.
One hundred percent tumor induction in mouse skin after repeated beta irradiation in a limited dose range.
Repeated beta irradiation of the backs of mice three times a week with radiation doses of 250 to 1180 cGy per exposure induced 100% incidence of tumors. The incidence of skin tumors appeared to be determined by the total number of repeated exposures in this dose range. An abrupt delay in tumor emergence was observed when the radiation dose was reduced from 250 to 150 cGy per exposure, indicating the existence of a critical threshold. Mouse skin resembles human skin rather than rat skin in its response to radiation.