The short‐term starvation tolerance of alate and apterous morphs and the effect of periods of starvation on the longevity and fecundity of alate adults were evaluated in the grain aphid, Sitobion avenae (Fabricius) (Hemiptera: Aphididae). Alate adults exhibited a proportionally larger length of survival compared with apterous adults under continuous starvation conditions. Newly molted pre‐reproductive adults were starved for 0–96 h and their survival rate on the 1st day after recovering with food was not significantly different from that of control aphids. Starvation reduced lifetime fecundity, but increased the reproductive rate immediately after nutrition being improved. Fecundity and longevity after 24, 48, 72, and 96 h of starvation were significantly higher than after 120 or 144 h of starvation. However, no significant differences were observed for alate adults after 24, 48, 72, or 96 h of starvation. This study suggests that the ability of alatae to adapt to brief periods of starvation could be one of the important factors affecting the reproductive success of aphids during delays in locating host plants.

In this research, the volatile organic compounds (VOCs) produced based on C. fimbriata exhibited strong antifungal activity against the fungal pathogen A. alternata . Our aim is to explore their bacteriostatic components.

Species of Ceratocystis and allied genera are pathogens of many trees, including Cunninghamia lanceolata. During a survey of 2020, we found a serious wilt disease of C. lanceolata in Yunnan Province, China. Three different fungi resembling Ceratocystis and allied genera were consistently isolated from discoloured foliage and stems on C. lanceolata. Morphological and DNA sequence comparisons based on 60S and LSU gene regions showed that the pathogens were Ceratocystis and related species. We included 4 isolates identified as C. acaciivora = C. manginecans, 10 isolates identified as Berkeleyomyces basicola ≡ Thielaviopsis basicola, and 1 isolate identified as Chalaropsis sp., from 3 geographical locations. Pathogenicity tests on potted plants showed that all three species were pathogenic. To our knowledge, this is the first report Ceratocystis acaciivora,B. basicola and Chalaropsis sp. causing C. lanceolata wilt in China.

Microorganism-produced volatile organic compounds (VOCs) are considered promising environmental-safety fumigants in food preservation. In this study, the VOCs from fungal Ceratocystis fimbriata strains (WSJK-1, Mby) were tested against postharvest fungi Monilinia laxa, Fusarium oxysporum, Monilinia fructicola, Botrytis cinerea, Alternaria solani, and Aspergillus flavus in vitro. The mycelial growth was significantly inhibited, in particular M. fructicola and B. cinerea (76.95, 76.00%), respectively. VOCs were identified by headspace solid-phase microextraction coupled with Gas Chromatography–Mass Spectrometry (HS-SPME-GC–MS); 40 compounds were identified. The antifungal activity of 21 compounds was tested by the minimum inhibitory concentrations (MIC) value. Benzaldehyde, 2-Phenylethanol, and 1-Octen-3-ol showed strong antifungal activity with the MIC in vitro ranging from 0.094 to 0.284 ml L−1 depending on the pathogen tested. The optical microscope showed serious morphological damage, including cell deformation, curling, collapse, and deficiency in mycelial or conidia cell structures treated with C. fimbriata VOCs and pure compounds. In vivo tests, C. fimbriata VOCs decreased brown rot severity in peaches, and compounds Benzaldehyde and 2-Phenylethanol could reduce peach brown rot in peaches at 60 μl L−1. The VOCs produced by C. fimbriata strain have good antifungal effects; low concentration fumigation could control peach brown rot. Its fragrance is fresh, safe, and harmless, and it is possible to replace chemical fumigants. It could be used as a potential biofumigant to control fruit postharvest transportation, storage, and food preservation. To the best of our knowledge, this is the first report on the antifungal activity and biocontrol mechanism of VOCs produced by C. fimbriata.

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