摘要:
Crystal toxins produced by different strains of entomopathogenic Bacillus thuringiensis (Bt) have been characterized and widely applied as commercial biological pesticides owing to their excellent insecticidal properties. This study aimed to identify novel bacterial strains effective in controlling Spodoptera exigua Hübner, Helicoverpa armigera Hübner, and Spodoptera litura Fabricius. Fifteen culturable bacterial strains were isolated from 60 dead larvae (H. armigera and S. exigua) collected in the field. The biochemical characteristics and 16S rRNA sequences of these strains indicated that one strain (B7) was Lysinibacillus sp., 12 strains (B1, B3, B4, B5, B6, B8, P2, P3, P4, P5, P6, and DW) were Bt kurstaki, and P2-2 and B2 were Bacillus velezensis subsp. Laboratory bioassays indicated that strains B3, P6, B6, and P4 showed high toxicity to second-instar larvae of S. exigua, with LC50 values of 5.11, 6.74, 205.82, and 595.93 µg/ml, respectively; while the strains P5, B5, B6, and P6, were the most efficient against second-instar larvae of H. armigera with LC50 values of 725.82, 11,022.72, 1,282.90, 2,005.28, respectively, and strains DW, P3, P2, and B4 had high insecticidal activity against second-instar larvae of S. litura with LC50 values of 576.69, 1,660.96, 6,309.42, and 5,486.10 µg/ml, respectively. In conclusion, several Bt kurstaki strains with good toxicity potential were isolated and identified in this study. These strains are expected to be useful for biointensive integrated pest management programs to reduce the use of synthetic insecticides.
摘要:
Eleusine indica has become a global nuisance weed and has evolved resistance to glufosinate. The involvement of target-site resistance (TSR) in glufosinate resistance in E. indica has been elucidated, while the role of nontarget-site resistance (NTSR) remains unclear. Here, we identified a glufosinate-resistant (R) population that is highly resistant to glufosinate, with a resistance index of 13.5-fold. Molecular analysis indicated that the resistance mechanism of this R population does not involve TSR. In addition, pretreatment with two known metabolic enzyme inhibitors, the cytochrome P450 (CYP450) inhibitor malathion and the glutathione S-transferase (GST) inhibitor 4-chloro-7-nitrobenzoxadiazole (NBD-Cl), increased the sensitivity of the R population to glufosinate. The results of subsequent RNA sequencing (RNA-seq) and quantitative real-time PCR (RT-qPCR) suggested that the constitutive overexpression of a GST gene (GSTU3) and three CYP450 genes (CYP94s and CYP71) may play an important role in glufosinate resistance. This study provides new insights into the resistance mechanism of E. indica.
摘要:
The ETHYLENE INSENSITIVE3-LIKE (EIL) family is one of the most important transcription factor (TF) families in plants and is involved in diverse plant physiological and biochemical processes. In this study, ten EIL transcription factors (CsEILs) in sweet orange were systematically characterized via whole-genome analysis. The CsEIL genes were unevenly distributed across the four sweet orange chromosomes. Putative cis-acting regulatory elements (CREs) associated with CsEIL were found to be involved in plant development, as well as responses to biotic and abiotic stress. Notably, quantitative reverse transcription polymerase chain reaction (qRT-PCR) revealed that CsEIL genes were widely expressed in different organs of sweet orange and responded to both high and low temperature, NaCl treatment, and to ethylene-dependent induction of transcription, while eight additionally responded to Xanthomonas citri pv. Citri (Xcc) infection, which causes citrus canker. Among these, CsEIL2, CsEIL5 and CsEIL10 showed pronounced upregulation. Moreover, nine genes exhibited differential expression in response to Candidatus Liberibacter asiaticus (CLas) infection, which causes Citrus Huanglongbing (HLB). The genome-wide characterization and expression profile analysis of CsEIL genes provide insights into the potential functions of the CsEIL family in disease resistance.
作者机构:
[Huang, Guo-Hua; Xiao, Zhengkun; Jin, Ruoheng] Hunan Agr Univ, Coll Plant Protect, Hunan Prov Key Lab Biol & Control Plant Dis & Inse, Changsha, Peoples R China.;[Nakai, Madoka] Tokyo Univ Agr & Technol, Fuchu, Tokyo 1838509, Japan.;[Huang, Guo-Hua] Hunan Agr Univ, Coll Plant Protect, Hunan Prov Key Lab Biol & Control Plant Dis & Inse, Changsha 410128, Hunan, Peoples R China.;[Nakai, Madoka] Tokyo Univ Agr & Technol, Dept Appl Biol Sci, Tokyo, Japan.
通讯机构:
[Madoka Nakai; Madoka Nakai Madoka Nakai Madoka Nakai] D;[Guo-Hua Huang; Guo-Hua Huang Guo-Hua Huang Guo-Hua Huang] H;Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, College of Plant Protection, Hunan Agricultural University, Changsha, People's Republic of China<&wdkj&>Department of Applied Biological Science, Tokyo University of Agriculture and Technology, Tokyo, Japan
通讯作者:
Wei Li<&wdkj&>Liangying Dai<&wdkj&>Shiming Liu
作者机构:
[Cheng, Rong; Yi, Tuyong; Liu, Shiming; Li, Wei; Zheng, Xiang; Zhong, Chanjuan; Dai, Liangying] Hunan Agr Univ, Coll Plant Protect, Hunan Prov Key Lab Biol & Control Plant Dis & Inse, Changsha 410128, Peoples R China.;[Liu, Shiming; Zhao, Jie] Chinese Acad Agr Sci, Inst Plant Protect, State Key Lab Biol Plant Dis & Insect Pests, Beijing 100193, Peoples R China.;[Liu, Tyler H.] Univ Wisconsin, Coll Letters & Sci, Madison, WI 53706 USA.;[Zhu, Zhendong] Chinese Acad Agr Sci, Inst Crop Sci, Beijing 100081, Peoples R China.;[Xu, Jieting] Wimi Biotechnol Co Ltd, Changzhou 213000, Peoples R China.
通讯机构:
[Wei Li; Liangying Dai; Shiming Liu] H;Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, College of Plant Protection, Hunan Agricultural University , Changsha 410128 , P. R. China<&wdkj&>Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, College of Plant Protection, Hunan Agricultural University , Changsha 410128 , P. R. China<&wdkj&>State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences , Beijing 100193 , P. R. China
摘要:
Phytophthora sojae causes Phytophthora root and stem rot disease of soybean (Glycine max), leading to huge annual yield loss worldwide, but resistance to Phytophthora sojae (Rps) genes remains elusive. Soybean cultivar "Yudou 29" is resistant to P. sojae strain PsMC1, and this study aimed to clone, identify, and characterize the Rps gene in Yudou 29 (RpsYD29) and clarify its functional mechanism. We map-based cloned RpsYD29 (ZINC FINGER PROTEIN03, GmZFP03) using the families of a cross between Yudou 29 and a P. sojae-susceptible soybean cultivar "Jikedou 2". P. sojae resistance of GmZFP03 was functionally validated by stable soybean genetic transformation and allele-phenotype association analysis. GmZFP03 was identified as a C2H2-type zinc finger protein transcription factor, showing 4 amino acid residue polymorphisms (V79F, G122-, G123-, and D125V) and remarkably different expression patterns between resistant and susceptible soybeans. Notably boosted activity and gene expression of superoxide dismutase (SOD) in resistant-type GmZFP03-expressed transgenic soybean, substantial enhancement of P. sojae resistance of wild-type soybean by exogenous SOD treatment, and GmZFP03 binding to and activation of 2 SOD1 (Glyma.03g242900 and Glyma.19g240400) promoters demonstrated the involvement of SOD1s in GmZFP03-mediated resistance to P. sojae strain PsMC1. Thus, this study cloned the soybean P. sojae-resistant GmZFP03, the product of which specifically targets 2 SOD1 promoters. GmZFP03 can be directly used for precise P. sojae-resistance soybean breeding. The soybean transcription factor ZINC FINGER PROTEIN03 targets and activates two SUPEROXIDE DISMUTASE1 promoters to confer resistance to Phytophthora sojae.
摘要:
Ascoviruses are insect-specific viruses that are thought to utilize the cellular apoptotic processes of host larvae to produce numerous virion-containing vesicles. In this study, we monitored the in vivo infection processes of Heliothis virescens ascovirus 3h (HvAV-3h) to illustrate the regulated cell death (RCD) of host cells. Transmission electron microscopic observations did not reveal any morphological markers of apoptosis in the fat bodies or hemocytes of HvAV-3h-infected Helicoverpa armigera or Spodoptera exigua larvae. However, several hemocytes showed the morphological criteria for necrosis and/or pyroptosis. Further in vitro biochemical tests were performed to confirm the RCD type of host cells after infection with HvAV-3h. Different morphological characteristics were found between the early (prior to 24 hours post-infection, [hpi]) and later (48 to 120 hpi) stages in both HvAV-3h infected larval fat bodies and hemocytes. In the early stages, the virions could only be found in several adipohemocytes, and the fat bodies were cleaving their contained lipid inclusions into small lipid dots. In the later stage, both fat bodies and hemocytes were filled with numerous virions. According to the morphological characteristics of HvAV-3h infected larval fat bodies or hemocytes, the pathogenic characteristics and infection patterns of HvAV-3h in the host larvae were described, and the systematic pathogenic mode of ascovirus infection was refined in this study. This study details the complete infection process of ascoviruses, which provides insights into the relationship between a pathogenesis of an insect virus and the RCD of different host tissues at different stages of infection. IMPORTANCE Viruses and other pathogens can interrupt host cellular apoptosis to gain benefits, such as sufficient resources and a stable environment that enables them to complete their replication and assembly. It is unusual for viruses to code proteins with homology to caspases, which are commonly recognized as apoptosis regulators. Ascoviruses are insect viruses with special cytopathology, and they have been hypothesized to induce apoptosis in their host larvae via coding a caspase-like protein. This enables them to utilize the process of cellular apoptosis to facilitate vesicle formation and replication. However, our previous studies revealed different trends. The fat bodies and hemocytes of Heliothis virescens ascovirus 3h (HvAV-3h)-infected larvae did not show any morphological markers of apoptosis but did display necrosis and/or pyroptosis morphological characteristics. The pathogenic characteristics and infection patterns of HvAV-3h in the host larvae were described, which can help us understand the relationship between the pathogenesis of an insect virus and host RCD.
作者机构:
[Hou, Maolin; Zhong, Yuqi] Chinese Acad Agr Sci, Inst Plant Protect, State Key Lab Biol Plant Dis & Insect Pests, Beijing 100093, Peoples R China.;[Zhong, Yuqi; Liao, Xiaolan] Hunan Agr Univ, Coll Plant Protect, Changsha 410028, Peoples R China.
通讯机构:
[Maolin Hou] S;State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100093, China
关键词:
biological control;Cyrtorhinus lividipennis;fitness;low temperature storage;predation;reproduction
摘要:
Abstract: Simple Summary Cyrtorhinus lividipennis Reuter (Hemiptera: Miridae) is an important predator of planthoppers and leafhoppers in rice fields. Augmentative biological control has been practiced successfully in many agroecosystems. However, one of the primary obstacles to augmentative biological control is obtaining natural enemies in sufficient numbers and quality when required for release. The development of the low-temperature storage (LTS) technique has been pivotal in ensuring the flexibility and efficiency of the mass production of biological control agents. Here, we measured the effects of LTS on the predatory capacity and reproduction of C. lividipennis adults and the fitness of the F1 generation. The results are expected to improve the successful utilization of the predator in an IPM program. Abstract 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. Keywords: Cyrtorhinus lividipennis; predation; reproduction; fitness; low temperature storage; biological control
摘要:
In insects, lipids and trehalose are the primary energy reserves and sources, and their metabolism is controlled by a variety of physiological processes. Adipokinetic hormone receptor (AKHR) has been reported to be involved in glycolipid metabolism and immune response, however, is an uncharted territory in Helicoverpa armigera. In the present study, the full-length cDNA encoding AKHR was isolated from H. armigera. The HaAKHR contains a seven-transmembrane domain, which was a characteristic of G-protein coupled receptors. The expression profile analysis revealed that HaAKHR was highly expressed in fat body of newly emerged female adults and highly expressed in the immature stage. The content of triglyceride (TAG) in fat body increased significantly after silencing of HaAKHR, however, the trehalase activity and the expression of trehalose-6-phosphate synthase (TPS) were decreased in hemolymph. Furthermore, the expression level of HaAKHR was significantly upregulated when infected with different kinds of entomopathogenic microbes. The above results suggested that HaAKHR plays an important role in regulating glycolipid metabolism and immune response in H. armigera, and contribute to understanding the underlying mechanism of host-pathogen interactions in H. armigera.
通讯作者:
Zhenchuan Mao<&wdkj&>Yunsheng Wang<&wdkj&>Bingyan Xie<&wdkj&>Zhenchuan Mao Zhenchuan Mao Zhenchuan Mao<&wdkj&>Yunsheng Wang Yunsheng Wang Yunsheng Wang<&wdkj&>Bingyan Xie Bingyan Xie Bingyan Xie
作者机构:
[Mao, Zhenchuan; Jiao, Yang; Li, Yan; Xie, Bingyan; Ling, Jian; Yang, Yuhong; Jiang, Lijun; Zhao, Jianlong] Chinese Acad Agr Sci, Inst Vegetables & Flowers, State Key Lab Vegetable Biobreeding, Beijing, Peoples R China.;[Yang, Yu] Shandong Acad Agr Sci, Inst Vegetables, Jinan, Shandong, Peoples R China.;[Yang, Yu] Shandong Acad Agr Sci, Inst Modern Agr Yellow River Delta, Jinan, Shandong, Peoples R China.;[Wang, Yunsheng] Hunan Agr Univ, Coll Plant Protect, Changsha, Hunan, Peoples R China.
通讯机构:
[Zhenchuan Mao; Bingyan Xie; Zhenchuan Mao Zhenchuan Mao Zhenchuan Mao; Bingyan Xie Bingyan Xie Bingyan Xie] S;[Yunsheng Wang; Yunsheng Wang Yunsheng Wang Yunsheng Wang] C;College of Plant Protection, Hunan Agricultural University, Changsha, Hunan, China<&wdkj&>State Key Laboratory of Vegetable Biobreeding, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, China
摘要:
Root-knot nematodes (RKNs) are infamous plant pathogens in tomato production, causing considerable losses in agriculture worldwide. Mi-1 is the only commercially available RKN-resistance gene; however, the resistance is inactivated when the soil temperature is over 28 °C. Mi-9 in wild tomato (Solanum arcanum LA2157) has stable resistance to RKNs under high temperature but has not been cloned and applied. In this study, a chromosome-scale genome assembly of S. arcanum LA2157 was constructed through Nanopore and Hi-C sequencing. Based on molecular markers of Mi-9 and comparative genomic analysis, the localization region and candidate Mi-9 genes cluster consisting of seven nucleotide-binding sites and leucine-rich repeat (NBS-LRR) genes were located. Transcriptional expression profiles confirmed that five of the seven candidate genes were expressed in root tissue. Moreover, virus-induced gene silencing of the Sarc_034200 gene resulted in increased susceptibility of S. arcanum LA2157 to Meloidogyne incognita, and genetic transformation of the Sarc_034200 gene in susceptible Solanum pimpinellifolium conferred significant resistance to M. incognita at 25 °C and 30 °C and showed hypersensitive responses at nematode infection sites. This suggested that Sarc_034200 is the Mi-9 gene. In summary, we cloned, confirmed and applied the heat-stable RKN-resistance gene Mi-9, which is of great significance to tomato breeding for nematode resistance.
摘要:
As a subtropical and tropical tree, bayberry (Myrica rubra) is an important fruit tree grown commercially in southern China. Interestingly, our studies found that the fruit quality of bayberry with accompanying ryegrass was significantly improved, but its mechanism remains unclear. The aim of this study was to explore the mechanism of accompanying ryegrass on the beneficial effect of the fruit quality of bayberry by measuring the vegetative growth parameters, fruit parameters with economic impact, physical and chemical properties of rhizosphere soil, microbial community structure, and metabolites of the bayberry with/without ryegrass. Notably, the results revealed a significant difference between bayberry trees with and without accompanying ryegrass in fruit quality parameters, soil physical and chemical properties, microbial community structure, and metabolites. Compared with the control without accompanying ryegrass, the planting of ryegrass increased the titratable sugar, vitamin C, and titratable flavonoid contents of bayberry fruits by 2.26%, 28.45%, and 25.00%, respectively, and decreased the titratable acid contents by 9.04%. Furthermore, based on 16S and ITS amplicon sequencing of soil microflora, the accompanying ryegrass caused a 12.47% increment in Acidobacteriota while a 30.04% reduction in Actinobacteria was recorded, respectively, when compared with the bayberry trees without ryegrass. Redundancy discriminant analysis of microbial communities and soil properties indicated that the main variables of the bacterial community included available nitrogen, available phosphorus, exchangeable aluminum, and available kalium, while the main variables of the fungal community included exchangeable aluminum, available phosphorus, available kalium, and pH. In addition, the change in microbial community structure was justified by the high correlation analysis between microorganisms and secondary metabolites. Indeed, GC-MS metabolomics analysis showed that planting ryegrass caused a 3.83%–144.36% increase in 19 metabolites such as 1,3-Dipentyl-heptabarbital and carbonic acid 1, respectively, and a 23.78%–51.79% reduction of 5 metabolites compared to the bayberry trees without the accompanying ryegrass. Overall, the results revealed the significant change caused by the planting of ryegrass in the physical and chemical properties, microbiota, and secondary metabolites of the bayberry rhizosphere soils, which provides a new insight for the ecological improvement of bayberry.