Albertsenfriedrichsen3232

These results highlight the potential of C15surfactin A as a biocontrol agent against Xoo in rice.Diamondback moth (DBM), Plutella xylostella, is an important pest of crucifers worldwide. The extensive use of flubendiamide has led to the development of resistance in field populations and reports of control failures. In this study, the lab-selected (Rf) and field-collected (Rb) flubendiamide-resistant strains of P. xylostella with LC50 resistance ratios of 1890-fold and 1251-fold, respectively, were used, as well as a lab-reared flubendiamide-susceptible strain (S). The results showed that the fecundity of the Rf and Rb-resistant strains was significantly lower than that of S strain. The contents of vitellin and transcripts of P. xylostella vitellogenin (PxVg) and P. xylostella vitellogenin receptor (PxVgR) genes in the Rf and Rb strains were significantly higher than those of S strains at 0-48 h after adult eclosion. At 96 h after eclosion, the content of vitellin in the Rf and Rb strains did not differ significantly from those of S strains, whereas transcripts of the PxVg and PxVgR genes in the Rf and Rbnism of fecundity reduction concurrent with flubendiamide-resistance in P. xylostella.Pyrethroid resistance has been a major hurdle limiting the effective control of bed bugs (Cimex lectularius L.). SCH900353 inhibitor Alternative approaches that include the use of plant essential oils (EOs) have been proposed for effective management of bed bugs. However, EO resistance level comparisons between pyrethroid susceptible and resistant bed bug populations have not been previously conducted. The goal of this study was twofold (i) determine deltamethrin resistance levels and associated resistance mechanisms in the field-collected Knoxville strain and (ii) quantify resistance levels of the Knoxville strain to five EOs (thyme, oregano, clove, geranium and coriander), their major insecticidal constituents (thymol, carvacrol, eugenol, geraniol and linalool) and an EO-based product (EcoRaider®). First, we found that the Knoxville strain was 72,893 and 291,626 fold more resistant to topically applied deltamethrin in comparison to the susceptible Harlan strain at the LD25 and LD50 lethal dose levels, respectively. Synergist bioassays and detoxification enzyme assays revealed significantly higher activity of cytochrome P450 and esterase enzymes in the resistant Knoxville strain. Further, Sanger sequencing revealed the presence of the L925I mutation in the voltage-sensitive sodium channel α subunit gene. The Knoxville strain that possesses both enzymatic and target site deltamethrin resistance, however, did not show any resistance to EOs, their major insecticidal constituents and EcoRaider® in topical bioassays (resistance ratio of ~1). In conclusion, this study demonstrated that a deltamethrin-resistant strain of bed bugs is susceptible to EOs and their insecticidal constituents.Tomato spotted wilt orthotospovirus (TSWV) causes devastating losses to agronomic and ornamental crops worldwide. Currently, there is no effective strategy to control this disease. Use of biotic inducers to enhance plant resistance to viruses maybe an effective approach. Our previous study indicated that Tagitinin A (Tag A) has a high curative and protective effect against TSWV. However, the underlying molecular mechanism of Tag A-mediated antiviral activity remains unknown. In this study, Tag A reduced the expression of the NSs, NSm genes was very low in untreated leaves following TSWV infection. In addition, the expression of all TSWV genes in the inoculated and systemic leaves was inhibited in the protective assay, and with an inhibition rate of more than 85% in systemic leaves. Tag A increased phenylalanine ammonia-lyase (PAL) activity in the curative and protective assays. The concentrations of jasmonic acid (JA) and jasmonic acid -isoleucine (JA-Ile) and the expression of its key gene NtCOI1 in Tag A-treated and systemic leaves of treated plants were significantly higher than those of the control plant. Furthermore, Tag A-induced resistance to TSWV could be eliminated by VIGS-mediated silencing of the NtCOI1 gene. These indicated that Tag A acts against TSWV by activating the JA defense signaling pathway.Descurainia sophia L. is one of the most notorious broadleaf weeds in winter wheat fields of China. In this study, 95 out of 163 (58.3%) D. sophia populations which were collected from provinces of Hebei, Shandong, Henan, Shanxi, Shaanxi and Jiangsu, have evolved resistance to tribenuron-methyl. The als1 and als2 were cloned in all test D. sophia populations, while als3 and als4 were identified only in some of the populations. Resistant mutations of Pro-197-Ser/Thr/Leu/His/Ala/Arg, Asp-376-Glu and Trp-574-Leu were identified in tribenuron-methyl-resistant (TR) D. sophia plants, while the Pro-197-Arg was first identified in D. sophia in this study. These resistant mutations displayed no preference between ALS1 and ALS2. However, Pro-197-Ser/Thr and Trp-574-Leu were identified in all ALS isozymes, while the other mutations were not. In addition, some resistant mutations displayed regional differences, the frequency of Pro-197-Ser in Shandong and Trp-574-Leu in Shanxi province is much higher than that in other provinces.Neurophysiological recordings were employed to quantify neuronal sensitivity to neurotoxic insecticides and assessed toxicity across field and laboratory fall armyworm (FAW) populations. Topical toxicity resistance ratios (RR) in field-collected FAW was 767-fold compared to laboratory strains and, importantly, a 1750-fold reduction in potency was observed for λ-cyhalothrin in neurophysiological assays. Field collected FAW were found to have a RR of 12 to chlorpyrifos when compared to the susceptible strain and was 8-fold less sensitive in neurophysiological assays. Surprisingly, there were no point mutations identified in the voltage-gated sodium channel known to cause pyrethroid resistance. For acetylcholinesterase, FAW had more than 80% of their nucleotide sequences consistent with A201 and F290 of the susceptible strains although 60% of the tested population was heterozygous for the G227A mutation. These data indicate that point mutations did not contribute to the high level of pyrethroid resistance and nerve insensitivity in this population of field collected FAW.