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Six transgenic rice, Oryza sativa L., lines (G6H1, G6H2, G6H3, G6H4, G6H5, and G6H6) expressing a fused CrylAb/Vip3H protein, were evaluated for resistance against the Asiatic rice borer, Chilo suppressalis (Walker) (Lepidoptera: Crambidae), and the stem borer Sesamia inferens (Walker) (Lepidoptera: Noctuidae) in the laboratory and field. The bioassay results indicated that the mortality of Asiatic rice borer and S. inferens neonate larvae on six transgenic lines from seedling to filling stage was up to 100% at168 h after infestation. The cumulative feeding area by Asiatic rice borer neonate larvae on all transgenic lines was significantly reduced compared with the untransformed parental 'Xiushui 110' rice. A 2-yr field evaluation showed that damage during the vegetative stage (deadheart) or during the reproductive stage (whitehead) caused by Asiatic rice borer and S. inferens for transgenic lines was much lower than the control. For three lines (G6H1, C6H2, and G6H6),no damage was found during the entire growing period. Estimation of fused Cry1Ab/Vip3H protein concentrations using PathoScreen kit for Bt-CrylAb/ lAc protein indicated that the expression levels of CrylAb protein both in main stems (within the average range of 0.006 - 0.073% of total soluble protein) and their flag leaves (within the average range of 0.001-0.038% of total soluble protein) were significantly different among six transgenic lines at different developmental stages. Both laboratory and field researches suggested that the transgenic rice lines have considerable potential for protecting rice from attack by both stem borers. [ABSTRACT FROM AUTHOR]

Seven synthetic herbivore-induced plant volatiles (HIPVs) and a mixture of nonanal + (Z)-3-hexen-1-ol were field tested for their ability to attract beneficial insects in an open cotton field. Eleven species of the main natural enemies of insect pests in cotton fields were studied. Significantly greater numbers of the ladybird beetle Coccinella septemptunctata were trapped on (Z)-3-hexenyl acetate-baited cards than on others that were HIPV baited or the control cards. Erigonidium graminicolum was attracted to traps baited with nonanal, (Z)-3-hexenyl acetate, and methyl salicylate (MeSA). The predatory bug Deraeocoris punctulatus was only attracted to traps baited with octanal, The predatory bug Onus similis responded to traps baited with 3,7-dimethyl,1,3,6-octatriene, nonanal, (Z)-3-hexenyl acetate, nonanal + (Z)-3-hexen-1-ol, and MeSA. Dimethyl octatriene, nonanal + (Z)-3-hexen-1-ol, and octanal significantly attracted the syrphid fly Paragus quadrifasciatus. The ladybird beetle Propylaea japonica, the green lacewing Chrysopa sinica, the bigeyed bug Geocoris pallidipennis, the syrphid fly Epistrophe balteata, and the parasitic wasp Campoletis chlorideae did not respond to any of the HIPVs tested. These results are discussed with regard to the potential of HIPVs as tools for recruiting natural enemies into cotton fields. [ABSTRACT FROM AUTHOR]

The autumn migration of Mythimna separata (Walker) (Lepidoptera: Noctuidae) across the Bohai Sea was observed with a scanning entomological radar and a searchlight trap at Beihuang, an island located in the center of the Bohai Gulf of northern China, in 2003-2006. During the autumn migration, M. separata flew at the altitudes of 50-500 m, with a displacement speed of 4-12 m/s, toward the southwest. Variations of area density of the radar targets and of catches in the searchlight trap through the night indicated that the flight duration of M. separata was ≈10 h. Based on these observations, M. separata that originated in northeastern China (i.e., Liaoning, Jilin, and Heilongjiang provinces and part of the Inner Mongolia autonomous region) could immigrate into eastcentral China and subsequently to southern China (i.e., Fujian, Guangdong, and Guangxi provinces) within a week for overwintering. [ABSTRACT FROM AUTHOR]

The field efficacy of two transgenic rice lines, containing the Cry1Ac gene from Bacillus thuringiensis (Bt) and the CpTI (cowpea trypsin inhibitor) gene, on the striped stem borer, Chilo suppressalis (Walker), and population variation in susceptibility of C. suppressalis to the Bt insecticidal protein Cry1Ac were evaluated in Fuzhou, Fujian Province of China. The results of an open field test showed that the two transgenic lines exhibited high efficacy against natural infestations of C. suppressalis. In contrast, the untransformed parental control line showed serious damage symptoms not only in untreated plots, but also in plots treated with insecticides. The cumulative number of C. suppressalis adults derived from transgenic rice lines was significantly lower than that from control lines with and without chemical control treatments. Our results show that transgenic rice lines expressing Cry1Ac and CpTI have great potential for protecting rice from C. suppressalis damage with reduced use of insecticides. Comparison of pupal weight and fecundity of C. suppressalis between transgenic and control treatments indicated that pupal weight significantly decreased after continuously feeding on transgenic rice lines, but there was no significant effect on fecundity. Adult females of C. suppressalis were collected from light traps to ascertain population variation in susceptibility to Bt toxins. Each female producing enough fertile eggs for bioassays was used as the parent of an isofemale line. Of 1,100 females collected, 395 isofemale lines produced enough offspring to be screened on a diet assay treated with Cry1Ac. The results showed that 51.7% of isofemale lines were differentiated as highly susceptible, 23.0% as moderately susceptible, and 23.8% with low susceptibility; 1.5% were nonsusceptible, with a survival rate >70% and similar development as on the non-Bt control diet. The results indicated significant variation in susceptibility to Cry1Ac in the C. suppressalis population, which should be considered for insect resistance management of Bt rice in the future. [ABSTRACT FROM AUTHOR]

The northward migration of Helicoverpa armigera (Hübner) and other moths in early summer was observed with radar in 2001 and 2002 at Langfang, Hebei province, China. Migratory flights typically occurred at heights up to 1.2 km above ground level (AGL), and high density layer concentrations frequently formed at 200-300 m AGL. Adult moths of local populations took off at dusk and ceased flight ≈0.5 h before sunrise with area density peaking ≈35 min after dusk. A strong dumb-bell pattern of echoes on the plan position indicator screen, indicating collective orientation of the targets, was evident in 2001, when targets were typically moving toward the northeast and when layering was associated with a temperature inversion and maximum wind speed. By contrast, there was no notable dumb-bell pattern in 2002, when targets were moving toward the northwest. However, orientations calculated from target and wind velocities showed that downwind common orientation also was occurring in 2002 and that the direction varied with the wind direction. The probable sources of the H. armigera observed at Langfang were deduced to be Henan province in 2001 and Shandong province in 2002, and the destination regions were Liaoning and Inner Mongolia. [ABSTRACT FROM AUTHOR]