Agricultural pests cause enormous losses in annual agricultural production.Understanding the evolutionary responses and adaptive capacity of agricultural pests under climate change is crucial for establishing sustaina...Agricultural pests cause enormous losses in annual agricultural production.Understanding the evolutionary responses and adaptive capacity of agricultural pests under climate change is crucial for establishing sustainable and environmentally friendly agricultural pest management.In this study,we integrate climate modeling and landscape genomics to investigate the distributional dynamics of the cotton bollworm(Helicoverpa armigera)in the adaptation to local environments and resilience to future climate change.Notably,the predicted inhabitable areas with higher suitability for the cotton bollworm could be eight times larger in the coming decades.Climate change is one of the factors driving the dynamics of distribution and population differentiation of the cotton bollworm.Approximately 19,000 years ago,the cotton bollworm expanded from its ancestral African population,followed by gradual occupations of the European,Asian,Oceanian,and American continents.Furthermore,we identify seven subpopulations with high dispersal and adaptability which may have an increased risk of invasion potential.Additionally,a large number of candidate genes and SNPs linked to climatic adaptation were mapped.These findings could inform sustainable pest management strategies in the face of climate change,aiding future pest forecasting and management planning.展开更多
Background Cotton(Gossypium spp.) is an important commercial crop being cultivated worldwide, but its production is hampered by many insect pests. The cotton aphid, Aphis gossypii Glover, is a key pest with increasing...Background Cotton(Gossypium spp.) is an important commercial crop being cultivated worldwide, but its production is hampered by many insect pests. The cotton aphid, Aphis gossypii Glover, is a key pest with increasing resistance to chemical insecticides. To explore eco-friendly management alternatives, this study evaluates the pathogenic potential of indigenous entomopathogenic fungi, isolated from cotton-growing regions of Tamil Nadu, India, via the ‘Galleria bait method'.Results Five entomopathogenic fungi were isolated and identified as Beauveria spp. based on cultural and morphological features. Molecular characterization by amplification of internal transcribed spacer-ribosomal DNA(ITS-rDNA) regions confirmed the isolates as B. bassiana. Among them, isolate B5(accession number: PP503009) exhibited the highest virulence, inducing 96.67% mortality at 7 days after treatment(DAT) with the concentration of 1 × 10^(8) spores·mL^(-1). The median lethal concentration(LC_(50)) and median lethal time(LT_(50)) values were 9.75 × 10^(4) spores·mL^(-1) at 7 DAT and 72.31 h at 1 × 10^(8) spores·mL^(-1), respectively. Scanning electron microscopy(SEM) images highlighted a progression of infection stages of B5, including spore attachment(24 h post infection(hpi)), hyphal penetration(48 hpi), and conidiogenesis(72 hpi).Conclusion The isolate B5 proved to be a promising candidate for the development of biopesticides for sustainable cotton aphid management in Tamil Nadu, India.展开更多
基金funded by the National Natural Science Foundation of China(32372546)Shenzhen Science and Technology Program(KQTD20180411143628272)+1 种基金the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences and STI 2030-Major Projects(2022ZD04021)the National Key Research and Development Program of China(2023YFD2200700)。
文摘Agricultural pests cause enormous losses in annual agricultural production.Understanding the evolutionary responses and adaptive capacity of agricultural pests under climate change is crucial for establishing sustainable and environmentally friendly agricultural pest management.In this study,we integrate climate modeling and landscape genomics to investigate the distributional dynamics of the cotton bollworm(Helicoverpa armigera)in the adaptation to local environments and resilience to future climate change.Notably,the predicted inhabitable areas with higher suitability for the cotton bollworm could be eight times larger in the coming decades.Climate change is one of the factors driving the dynamics of distribution and population differentiation of the cotton bollworm.Approximately 19,000 years ago,the cotton bollworm expanded from its ancestral African population,followed by gradual occupations of the European,Asian,Oceanian,and American continents.Furthermore,we identify seven subpopulations with high dispersal and adaptability which may have an increased risk of invasion potential.Additionally,a large number of candidate genes and SNPs linked to climatic adaptation were mapped.These findings could inform sustainable pest management strategies in the face of climate change,aiding future pest forecasting and management planning.
文摘Background Cotton(Gossypium spp.) is an important commercial crop being cultivated worldwide, but its production is hampered by many insect pests. The cotton aphid, Aphis gossypii Glover, is a key pest with increasing resistance to chemical insecticides. To explore eco-friendly management alternatives, this study evaluates the pathogenic potential of indigenous entomopathogenic fungi, isolated from cotton-growing regions of Tamil Nadu, India, via the ‘Galleria bait method'.Results Five entomopathogenic fungi were isolated and identified as Beauveria spp. based on cultural and morphological features. Molecular characterization by amplification of internal transcribed spacer-ribosomal DNA(ITS-rDNA) regions confirmed the isolates as B. bassiana. Among them, isolate B5(accession number: PP503009) exhibited the highest virulence, inducing 96.67% mortality at 7 days after treatment(DAT) with the concentration of 1 × 10^(8) spores·mL^(-1). The median lethal concentration(LC_(50)) and median lethal time(LT_(50)) values were 9.75 × 10^(4) spores·mL^(-1) at 7 DAT and 72.31 h at 1 × 10^(8) spores·mL^(-1), respectively. Scanning electron microscopy(SEM) images highlighted a progression of infection stages of B5, including spore attachment(24 h post infection(hpi)), hyphal penetration(48 hpi), and conidiogenesis(72 hpi).Conclusion The isolate B5 proved to be a promising candidate for the development of biopesticides for sustainable cotton aphid management in Tamil Nadu, India.
文摘[目的]溴虫氟苯双酰胺是新型间二酰胺类杀虫剂,本文通过棉铃虫(Helicoverpa armigera)对溴虫氟苯双酰胺的室内抗性发展情况的探究和田间抗性等位基因频率的调查,全面评估棉铃虫对溴虫氟苯双酰胺的抗性风险,为该药剂的合理使用提供科学依据。[方法]用溴虫氟苯双酰胺对棉铃虫室内品系SCD进行连续多代筛选,根据阈性状分析法计算其抗性现实遗传力(realized heritability of resistance,h^(2));用F_(2)筛选法检测棉铃虫田间种群对溴虫氟苯双酰胺的抗性等位基因频率。[结果]70%左右死亡率的选择压力下连续筛选10代和20代,棉铃虫对溴虫氟苯双酰胺的抗性现实遗传力(h^(2))分别为0.1268和0.0592;在筛选过程中棉铃虫对溴虫氟苯双酰胺的抗性倍数为1.9~4.5,到第20代时抗性倍数为2.8。2022年华北棉区325个棉铃虫田间单雌系F_(2)代幼虫共31200头在溴虫氟苯双酰胺诊断浓度下全部死亡,说明检测的田间单雌系均未携带抗性等位基因,华北棉区棉铃虫田间种群对溴虫氟苯双酰胺的抗性等位基因频率为0.0008(95%CI:0.0000~0.0050)。[结论]棉铃虫室内品系连续多代筛选对溴虫氟苯双酰胺的抗性发展缓慢,F_(2)筛选检测表明田间种群的起始抗性等位基因频率低,因此棉铃虫对溴虫氟苯双酰胺的抗性风险低,可有效用于棉铃虫的防治。
