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91.
本研究明确了乙基多杀菌素和氯虫苯甲酰胺丸粒化包衣后对玉米种子的安全性和玉米幼苗对草地贪夜蛾的防治效果,为玉米苗期草地贪夜蛾防治提供新技术。首先在室内验证了乙基多杀菌素和氯虫苯甲酰胺拌土后对草地贪夜蛾的防治效果,又进行了种子丸粒化包衣处理,测定了丸粒化包衣方式下药剂对种子萌发的影响和对草地贪夜蛾的防治效果。结果表明,250 mg/kg的乙基多杀菌素和氯虫苯甲酰胺拌土处理后,草地贪夜蛾对14天的玉米苗的取食率分别为1.67%、5.01%,与对照组取食率27.02%差异显著。药种比为1:100和1:200的乙基多杀菌素和氯虫苯甲酰胺丸粒化包衣处理组与对照组的发芽率之间无显著差异。乙基多杀菌素和氯虫苯甲酰胺丸粒化包衣处理组在播种后第7天对草地贪夜蛾广州种群防治效果显著,其中药种比为1:100的乙基多杀菌素丸粒化包衣处理组致死率最高为89%;两药剂丸粒化包衣处理组在播种后第21天对草地贪夜蛾云南种群仍有较好防治效果,两个浓度的乙基多杀菌素丸粒化包衣处理对草地贪夜蛾的致死率均达100%。本研究表明玉米种子丸粒化包衣技术可有效防控玉米苗期草地贪夜蛾的危害。  相似文献   
92.
The jasmonic acid (JA) pathway plays crucial roles in plant defence against pathogens and herbivores. Rice stripe virus (RSV) is the type member of the genus Tenuivirus. It is transmitted by the small brown planthopper (SBPH) and causes damaging epidemics in East Asia. The role(s) that JA may play in the tripartite interaction against RSV, its host, and vector are poorly understood. Here, we found that the JA pathway was induced by RSV infection and played a defence role against RSV. The coat protein (CP) was the major viral component responsible for inducing the JA pathway. Methyl jasmonate treatment attracted SBPHs to feed on rice plants while a JA-deficient mutant was less attractive than wild-type rice. SBPHs showed an obvious preference for feeding on transgenic rice lines expressing RSV CP. Our results demonstrate that CP is an inducer of the JA pathway that activates plant defence against RSV while also attracting SBPHs to feed and benefitting viral transmission. This is the first report of the function of JA in the tripartite interaction between RSV, its host, and its vector.  相似文献   
93.
Systemic necrosis often occurs during viral infection of plants and is thought mainly to be the result of long-term stress induced by viral infection. Potato virus X (PVX) encodes the P25 pathogenicity factor that triggers a necrotic reaction during PVX-potato virus Ysynergistic coinfection. In this study, we discovered that NbALY916, a multifunctional nuclear protein, could interact with P25. When NbALY916 expression was reduced by tobacco rattle virus (TRV)-based virus-induced gene silencing, the accumulation of P25 was increased, which would be expected to cause more severe necrosis. However, silencing of NbALY916 reduced the extent of cell death caused by P25. Furthermore, we found that overexpression of NbALY916 increased the accumulation of H2O2 and triggered more extensive cell death when coexpressed with P25, even though accumulation of P25 was itself reduced by the increased expression of NbALY916. Furthermore, transient expression of P25 specifically induced the expression of NbALY916 mRNA, but not the mRNAs of three other ALYs in Nicotiana benthamiana. In addition, we showed that silencing of NbALY916 or transient overexpression of NbALY916 affected the infection of PVX in N. benthamiana. Our results reveal that NbALY916 has an antiviral role that, in the case of PVX, operates by inducing the accumulation of H2O2 and mediating the degradation of P25.  相似文献   
94.
Traditional methods of identifying food‐borne pathogens are time consuming and laborious, so innovative methods for their rapid identification must be developed. Testing for bioluminescence pyrophosphate is a convenient and fast method of detecting pathogens without complex equipment. However, the sensitivity of the method is not as high as that of other methods, and it has a very high detection limit. In this study, the method was optimized to improve its sensitivity. The shortcomings of the method were first identified and corrected using dATPαS instead of dATP for the polymerase chain reaction (PCR), therefore reducing the background signal. Also, when the DNA template extracted from the food‐borne pathogens was purified, the new bioluminescence pyrophosphate assay had a limit of detection of <10 copy/μl or 10 colony‐forming units/ml, and its sensitivity was higher than that of fluorescent real‐time quantitative PCR. Moreover, a single copy of a food‐borne pathogen could be detected when a single DNA template was included in the PCR. Salmonella was detected in and isolated from 60 samples of broiler chicken, and the accuracy of the results was verified using a culture method (GB 4789.4–2010). These results showed that the new bioluminescence pyrophosphate assay has the advantages of an intuitive detection process, convenient operation, and rapid measurements. Therefore, it can be used for the rapid detection of pathogenic bacteria and probiotics in various fields.  相似文献   
95.
96.
Dysregulation of autophagy is associated with the neurodegenerative processes in Alzheimer's disease (AD), yet it remains controversial whether autophagy is a cause or consequence of AD. We have previously expressed the full‐length human APP in Drosophila and established a fly AD model that exhibits multiple AD‐like symptoms. Here we report that depletion of CHIP effectively palliated APP‐induced pathological symptoms, including morphological, behavioral, and cognitive defects. Mechanistically, CHIP is required for APP‐induced autophagy dysfunction, which promotes Aβ production via increased expression of BACE and Psn. Our findings suggest that aberrant autophagy is not only a consequence of abnormal APP activity, but also contributes to dysregulated APP metabolism and subsequent AD pathogenesis.  相似文献   
97.
Atherosclerosis is one of the most common and crucial heart diseases involving the heart and brain. At present, atherosclerosis and its major complications comprise the leading causes of death worldwide. Our purpose was to identify the role of ciRS‐7 in atherosclerosis. Tubulogenesis of HMEC‐1 cell was evaluated utilizing tube formation assay. Cell Counting Kit‐8 assay and flow cytometry were utilized to test viability and apoptosis. Migration assay was utilized to determine the migration capacity of experimental cells. Western blot was applied to examine apoptosis and tube formation‐associated protein expression. In addition, the above experiments were repeated when silencing ciRS‐7, overexpressing ciRS‐7, and upregulating miR‐26a‐5p. HMEC‐1 cells formed tube‐like structures over time. Silencing ciRS‐7 suppressed viability, migration, and tube formation but promoted apoptosis. Oppositely, overexpressing ciRS‐7 reversed the effect in HMEC‐1 cells. miR‐26a‐5p expression was elevated by silencing ciRS‐7 and reduced by overexpressing ciRS‐7. Moreover, overexpressing ciRS‐7 facilitated viability, migration, and tube formation via upregulating miR‐26a‐5p. Conclusively, overexpressing ciRS‐7 mobilized phosphoinositide 3‐kinase/protein kinase B (PI3K/AKT) pathway and suppressed c‐Jun N‐terminal kinase (JNK)/p38 pathway. ciRS‐7 exerted influence on apoptosis, viability, migration, and tube formation through mediating PI3K/AKT and JNK/p38 pathways by miR‐26a‐5p downregulation in HMEC‐1 cells.  相似文献   
98.
The progression of diabetic cardiomyopathy is related to cardiomyocyte dysfunction and apoptosis. Our previous studies showed that asporin (ASPN) was significantly increased in the myocardium of db/db mice through proteomics, and grape seed procyanidin B2 (GSPB2) significantly inhibited the expression of ASPN in the heart of db/db mice. We report here that ASPN played a critical role in glycated low‐density lipoproteins (gly‐LDL) induced‐cardiomyocyte apoptosis. We found that gly‐LDL upregulated ASPN expression. ASPN increased H9C2 cardiomyocyte apoptosis with down‐regulation of Bcl‐2, upregulation of transforming growth factor‐β1, Bax, collagen III, fibronectin, and phosphorylation of smad2 and smad3. However, GSPB2 treatment reversed ASPN‐induced impairments in H9C2 cardiomyocytes. These results provide evidence for the cardioprotective action of GSPB2 against ASPN injury, and thus suggest a new target for fighting against diabetic cardiomyopathy.  相似文献   
99.
Although interspecific competition has long been recognised as a major driver of trait divergence and adaptive evolution, relatively little effort has focused on how it influences the evolution of intraspecific cooperation. Here we identify the mechanism by which the perceived pressure of interspecific competition influences the transition from intraspecific conflict to cooperation in a facultative cooperatively breeding species, the Asian burying beetle Nicrophorus nepalensis. We not only found that beetles are more cooperative at carcasses when blowfly maggots have begun to digest the tissue, but that this social cooperation appears to be triggered by a single chemical cue – dimethyl disulfide (DMDS) – emitted from carcasses consumed by blowflies, but not from control carcasses lacking blowflies. Our results provide experimental evidence that interspecific competition promotes the transition from intraspecific conflict to cooperation in N. nepalensis via a surprisingly simple social chemical cue that is a reliable indicator of resource competition between species.  相似文献   
100.
The rice stem borer, Chilo suppressalis, is one of the most damaging insect pests to rice production worldwide. Although C. suppressalis has been the focus of numerous studies examining cold tolerance and diapause, plant–insect interactions, pesticide targets and resistance, and the development of RNAi‐mediated pest management, the absence of a high‐quality genome has limited deeper insights. To address this limitation, we generated a draft C. suppressalis genome constructed from both Illumina and PacBio sequences. The assembled genome size was 824.35 Mb with a contig N50 of 307 kb and a scaffold N50 of 1.75 Mb. Hi‐C scaffolding assigned 99.2% of the bases to one of 29 chromosomes. Based on universal single‐copy orthologues (BUSCO), the draft genome assembly was estimated to be 97% complete and is predicted to encompass 15,653 protein‐coding genes. Cold tolerance is an extreme survival strategy found in animals. However, little is known regarding the genetic basis of the winter ecology of C. suppressalis. Here, we focused our orthologous analysis on those gene families associated with animal cold tolerance. Our finding provided the first genomic evidence revealing specific cold‐tolerant strategies in C. suppressalis, including those involved in glucose‐originated glycerol biosynthesis, triacylglycerol‐originated glycerol biosynthesis, fatty acid synthesis and trehalose transport‐intermediate cold tolerance. The high‐quality C. suppressalis genome provides a valuable resource for research into a broad range of areas in molecular ecology, and subsequently benefits developing modern pest control strategies.  相似文献   
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