Low-temperature storage (LTS) is a way to adjust natural enemy development to meet field release needs and to protect natural enemies from the odds of long-distance transportation. The mirid bug Cyrtorhinus lividipennis Reuter (Hemiptera: Miridae) is an important predator of planthoppers and leafhoppers in rice fields. In this study, the LTS effects were measured on the predatory capacity and reproduction of the mirid adults (provided with 20% honey solution and stored at 13 °C for 12 days), and the fitness of the F1 generation of these adults. Higher predation of the eggs of the brown planthopper Nilaparvata lugens (Stål) (Hemiptera: Delphacidae) was observed in the post-storage females than in the control females. The functional responses of C. lividipennis adults, either exposed to LTS or not, to planthopper eggs fitted well with Holling type II functional responses. Longevity was not affected by LTS, whereas the number of offspring nymphs was 55.6% lower in the post-storage females than in the control females. The fitness of the offspring generation was not affected by the LTS of parental adults. The findings are discussed with their relevance to biological control.
Lilium brownii F. E. Brown ex Miellez var. viridulum Baker (Longya lily) is a variety of Lilium brownii F.E. Br. ex Miellez. We used HS-SPME and GC-MS to screened the tissues of L. brownii roots, stems, bulbs, and leaves and obtained 2,4-DTBP as an autotoxic substance for subsequent analysis. 2,4-DTBP was highly autotoxic in some treatment groups. Based on changes in physiological indicators, we carried out transcriptomic analysis to investigate the mechanisms of autotoxicity of substances on L. brownii and obtained 188,505 Unigenes. GO and KEGG enrichment analyses showed that L. brownii responded differently to different concentrations and treatment times of 2,4-DTBP. We observed significant changes in genes associated with ROS, phytohormones, and MAPK signaling cascades. 2,4-DTBP affects chloroplasts, the integrity of the respiratory electron transport chain, and ribosomes, causing L. brownii autotoxicity. Our findings provide a practical genomic resource for future research on L. brownii autotoxicity and evidence for the mechanism of action of autotoxic substances.
19 January 2010 in Chinese Journal of Eco-Agriculture