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Extensive unofficial planting of Bt cotton expressing Cry1Ac toxin has occured for the past two decades in northwestern China, and no mandatory refuge policy has been adopted. The status of Cry1Ac susceptibility of Helicoverpa armigera in this region has not been routinely monitored, nor has the susceptibility to Cry2Ab cotton which has not been released in China. The susceptibility of H. armigera populations to both toxins was assessed in 2014 and 2015 in two contrasting cotton farming systems across the region. Over the 2 years, the response to Cry1Ac of the nine H. armigera field populations sampled ranged from 3.16 to 16.94 μg ml−1 for LC50 and 0.013 to 0.741 μg ml−1 for IC50, and the baseline susceptibility of these strains to Cry2Ab ranged from 3.43 to 19.05 μg ml−1 for LC50 and 0.16 to 3.81 μg ml−1 for IC50. There was no significant difference in susceptibility to either Cry1Ac or Cry2Ab between small-holder and broad-acre farming. The susceptibility to Cry1Ac toxin in northwestern China is higher than that in northern China, while there was no difference for Cry2Ab between northwestern China and northern China. With high levels of adoption of Bt cotton and relatively limited natural refuge for H. armigera, it is important to consider resistance management measures for Bt cotton in northwestern China. [ABSTRACT FROM AUTHOR]

There have been few ecological studies of dung beetles (Coleoptera: Scarabaeidae) from the Black Sea Region of Turkey. In the RAMSAR-listed wetland system of the Kızılırmak Delta of Turkey’s central Black Sea coast, seasonal grazing by domesticated water buffalo produces plentiful dung from April to November. Twenty-three species of dung beetles from 13 genera of Aphodiinae and 4 genera of Scarabaeinae were collected from their dung on two adjacent soil types in 2013. The species were from three functional groups, namely dung dwelling (12), tunneling (10), and ball rolling (1). Thirteen and fourteen species were collected in spring/summer and autumn, respectively, with only 4 species in common. There was a distinct shift from Scarabaeinae (8 of 13 species) in spring/summer to Aphodiinae (10 of 14 species) in autumn. The ten species collected on the sandy clay loam soil were a subset of the 23 species on the sand dunes. On the sandy clay loam, high water tables in winter and soil cracking in summer may exclude deeper tunneling species. The 3:1 ratio of dung dwelling species on the sand compared to the sandy clay loam may suggest a more appropriate dung moisture regime over time that favors successful breeding on the sand. [ABSTRACT FROM AUTHOR]