[Review on the effects of heavy metal pollution on herbivorous insects].

Heavy metal pollution is one of the thorniest issues in the world, which is a serious threat to ecosystems and food security. As an important link of food chain and food web in the ecosystem, herbivorous insects play important role in the transfer and accumulation of heavy metals. Consequently, more and more attentions have been paid on the potential effects of heavy metal pollution on herbivorous insects.

[Effect of Bt rice straw returning in soil on the growth and reproduction of Eisenia fetida.].

Bacillus thuringiensis (Bt) protein can enter the soil through Bt crops straw returning to field, which may affect the growth and reproduction of soil animals, such as earthworms. Here, Bt rice (b2B138) and conventional rice (Anfeng A) straw were returned in soil to evaluate the impact of Bt rice on Eisenia fetida. Two varieties of rice straw were added into soil to breed E.

[Effects of lead stress on the growth and reproduction of Spodoptera litura fabricius (Lepidoptera:Noctuidae)].

Standard artificial diet was added with different concentration lead (Pb) to feed herbivorous insect Spodoptera litura larvae to study their growth and reproduction under the effects of Pb stress. With the increasing concentration Pb in the diet, the survival rate and body mass of the larvae at their different development stages (larvae, pupae, and adults) decreased. The minimum concentration of Pb which caused the significant decrease of the survival rate was 100 mg x kg(-1), and that caused a remarkable decrease of body mass was 50 mg x kg(-1).

[Effects of Bt corn straw insecticidal proteins on enzyme activities of Eisenia fetida].

Bacillus thuringiensis (Bt) proteins released from Bt corn can enter soil ecosystem via returning straw into field, root exudation, and pollen fluttering-down. In this study, the straws of Bt corn and its near-isogenic non-Bt line were added into soil with an application rate of 5% and 7.5% to breed Eisenia fetida, and the total protein content and the activities of acetylcholine esterase (AchE), glutathione peroxidase (GSH-PX), catalase (CAT), and superoxide dismutase (SOD) in E.

[Effects of reduced nitrogen application on the yield, quality, and economic benefit of sugarcane intercropped with soybean].

A two-factor field experiment of randomized block design was conducted in Guangzhou to investigate the effects of reduced nitrogen application on the yield, quality, and total biomass dynamic of sugarcane as well as the economic benefit of the sugarcane population under different sugarcane/soybean intercropping patterns. Neither N application nor intercropping pattern had significant effects on the yield and quality of sugarcane, and no significant differences were observed in the yield and quality of sugarcane among all treatments. The land equivalent ratio (LER) of sugarcane/soybean intercropping at different N application levels was from 1.