As a crucial and integral adaptation for thriving in diverse habitats, whether for survival or disease prevention and control, biofilm plays a vital role for most biocontrol bacteria, such as B. subtilis , Bacillus amyloliquefaciens, and plant-growth-promoting rhizobacteria (PGPR). However, the process of biofilm formation is intricate, and its regulatory mechanism remains unclear. In this study, we discovered that the regulatory protein MutL significantly influenced biofilm formation and exhibited a diminished colonization effectiveness on rice leaves. The mutant, lacking protein MutL expression, was unable to form biofilm with normal morphology and yielded only a quarter of the biofilm weight observed in the wild type B.subtilis YT1. In a petri dish confrontation assay examining the inhibitory effects on Rhizoctonia solani, no significant differences were observed between the mutant strain and the wild type YT1. Furthermore, through GFP fluorescent labeling technology, we conducted additional colonization tests, which demonstrated that the mutant failed to colonize rice stems effectively in the presence of R. solani. We hypothesize that the negative impact on biofilm formation resulted in inadequate colonization of rice stems, this combination accounts for the poor biocontrol efficacy against rice sheath blight, but it does not affect the normal growth of the strain or other biological phenotypes.

The purpose of this study is to discover and excavate more key factors and signaling pathways that regulate the formation intensity of biofilms and to fully reveal the possible models affecting biofilm formation. By using gene homologous recombination and bioinformatics technology, a MutL protein-directed deletion mutant strain was successfully constructed. The growth status of the mutant strain was observed, and it was confirmed that, except for the change in cell morphology, there were no significant differences in growth and reproduction between the mutant strain and the wild-type strain. By using the induced biofilm formation technique, the significant decrease in biofilm formation in the MutL mutant strain was successfully verified. The plate confrontation test confirmed that the inhibitory ability of the mutant strain against rice blast fungus was not significantly different from that of the WT strain. The colonization ability of the mutant strain on rice stems was tested, and it was confirmed that the colonization ability of the mutant strain was significantly lower than that of the WT strain. In terms of the prevention and control effect of rice blast disease, the mutant strain showed a significant decrease. By using transcriptomic big data, the gene and pathway expression differences between the mutant strain and the WT strain during biofilm formation were analyzed. The analysis revealed no significant correlation with the previously reported spo0A and tapA-sipW-tasA pathways. The key factor capB of the polyglutamic acid signaling pathway, which affects the formation of the biological model, was found to have a significant decrease in expression. A mechanical hypothesis was proposed: MutL may participate in regulating the formation intensity of Bacillus biofilms by regulating the formation of glutamic acid to polyglutamic acid.

With the development of material science and increasing awareness of ecological environmental protection, liquid biodegradable mulch films (LBDMs) have garnered significant public interest. In this research, new LBDMs were developed using hydrophobically modified polymer materials, surfactants, and photosensitive catalysts. Characterization by scanning electron microscopy (SEM) revealed good material compatibility. LBDMs exhibited excellent wettability and degradability, effectively covering soil surfaces and enhancing soil moisture conservation, with a degradation rate of 76.09% after 80 days of burial. The field performance experiment was conducted over two consecutive years, 2021 and 2022, to assess differences in soil temperature and moisture, peanut agronomic traits, pod traits, and yield under four treatments: non-mulching (CK), LBDMs, clear polyethylene mulch films (CPEMs), and black polyethylene mulch films (BPEMs). LBDMs increased soil temperature by 0.56 °C and soil moisture by 19.25%, accelerated the seedling stage by 4-to-6 days, and improved the average emergence rate by 15.91%. Furthermore, LBDMs significantly promoted peanut growth, and it increased yield by 14.34% compared to CK. LBDMs performed comparably to the two types of PE films in maintaining soil conditions and different crop phenotype traits, including plant height, branch number, yield, and quality, and they even outperformed PE films in productivity per plant and 100-kernel weight. These findings suggest that LBDMs are a promising eco-friendly alternative to traditional PE films.

Abstract To investigate the population dynamics and correlation between wheat aphids and their natural enemies, we conducted a checkerboard sampling study in Yantai, Shandong province from 2019 to 2022. The main types of wheat aphids observed were S. miscanthi and Rhopalosiphum padi. S. miscanthi was found to occur on May, while R. padi appeared on June. The population dynamics of S. miscanthi followed a parabolic pattern, with peak numbers reached in mid-to-late May, followed by a decline. Similarly, the population of mummified aphids also exhibited a parabolic trend, and there was a linear correlation between the number of mummified aphids and S. miscanthi. However, mummified aphids appeared 4–10 days later than S. miscanthi. Furthermore, the occurrence trends of wheat aphids and their natural enemies generally aligned with each other, except in 2020 when the natural enemies emerged 10 days later than wheat aphids. This indicated a clear follow-up relationship between mummified aphids and S. miscanthi, as well as an evident following relationship between the natural enemies and wheat aphids. In conclusion, our study highlights the interplay of population dynamics among wheat aphids, mummified aphids, and their natural enemies in the Yantai region. These findings can contribute to a better understanding of ecological interactions in agricultural ecosystems and potentially aid in the development of integrated pest management strategies.

苹果病虫害绿色防控关系到果品品质和质量安全,对促进苹果产业绿色高质量发展具有重要意义.综述了苹果病虫害绿色防控技术及研究进展,主要从监测预警、农药减量、物理防治、生物防治、生态调控等方面进行归纳总结,提出了苹果病虫害绿色防控存在的问题及今后的工作方向.

[目的]评价新型杀虫剂75 g/L阿维菌素·双丙环虫酯可分散液剂对苹果黄蚜的防治效果.[方法]于山东烟台 开展了连续2年的田间药效试验.[结果]75 g/L阿维菌素·双丙环虫酯可分散液剂37.5、45、56.25 g a.i./hm2处理对苹果黄蚜有良好的防治效果,药后7 d防效均在91.34％以上,且在试验剂量下对苹果安全无药害.[结论]75 g/L阿维菌素·双丙环虫酯可分散液剂对苹果黄蚜防效良好,可作为今后防治苹果黄蚜药剂选择的依据.

为明确宛氏拟青霉乙醇提取物ZNC(以下简称ZNC)在花生上的应用效果,于烟台市进行了田间试验.结果表明,施用ZNC能明显促进花生生长,用ZNC 40 mL拌花生种100 kg播种后,苗期和花期再进行2次叶面喷雾处理表现出效果最为显著,株高、叶面积和叶绿素含量较清水对照分别增加17.06 cm、5.88 cm2和1.61 mg/g.在诱导抗病性上,ZNC对花生叶斑病的最高防效达38.62％,显著提高了抗病性.在产量方面,施ZNC处理的花生产量增加6.80％～26.30％.总之,施用ZNC能够促进花生生长、提高产量、增强抗病性,可以在本地花生生产中推广应用.

橘小实蝇是为害果蔬的重大害虫,以成虫诱杀为主要作用方式的食诱技术是防治该害虫的重要方法.综述了目前橘小实蝇食诱剂的主要类型及研究进展,并对其在生产中搭配诱捕器、光波、化学物质等主要应用技术进行了归纳,提出了橘小实蝇食诱技术应用中存在的问题和今后的研究方向.

为筛选防治葡萄炭疽病安全、高效的生物药剂,采用菌丝生长速率法测定5种生物药剂对葡萄炭疽病菌的毒力,选取其中抑菌活性较好的4种药剂开展田间防效试验.室内毒力测定结果表明,丁子香酚、苦参碱、中生菌素、乙蒜素的EC50分别为0.50、20.03、22.05、33.04mg/L,均低于对照药剂代森锰锌的EC50值42.66mg/L,抑菌效果较好,而多抗霉素的EC50为3 420.15 mg/L,抑菌效果差.田间药效试验结果表明,0.3％丁子香酚可溶性液剂1 000-1 250倍液对葡萄炭疽病的防效最佳,为91.41％～93.49％,显著优于对照药剂80％代森锰锌可湿性粉剂800倍液,0.3％丁子香酚可溶性液剂1 500倍液、80％乙蒜素乳油1 000-1 500倍液防效虽低于对照药剂,但也均在80％以上,可作为与常规化学药剂轮换使用防控炭疽病的有效生物药剂进行推广应用.

[目的]明确鸡粪沼液与化学农药噻虫胺减量混用对韭菜迟眼蕈蚊的防治效果.[方法]分别采用胃毒触杀法和灌根法进行室内毒力测定和田间药效试验.[结果]鸡粪沼液稀释50倍与1 mg/L噻虫胺减量10％～40％混用,对韭菜迟眼蕈蚊3龄幼虫的毒力与1 mg/L噻虫胺差异不显著.鸡粪沼液50～100倍在药剂减少20％的情况下,桶混制剂对韭菜迟眼蕈蚊的田间防效与噻虫胺常规剂量相当.[结论]在使用噻虫胺防治韭菜迟眼蕈蚊时,建议鸡粪沼液稀释50～100倍,与噻虫胺减量20％混用.

[目的]明确新型杀菌剂10％四唑吡氨酯悬浮剂对黄瓜霜霉病的防治效果,为生产上应用提供科学依据.[方法]采用喷雾法于2016-2017年在山东省烟台市进行了田间药效试验.[结果]10％四唑吡氨酯悬浮剂对黄瓜霜霉病防治效果良好,第3次施药后14 d,30～90 g a.i./hm2处理防效仍在88.62％以上,优于对照药剂50％烯酰吗啉水分散粒剂(225 g a.i./hm2).[结论]10％四唑吡氨酯悬浮剂是一种防治黄瓜霜霉病较为理想的新型药剂,值得在黄瓜生产中推广应用.

为明确27％肟菌酯·戊唑醇悬浮剂对花生叶斑病的防治效果,2017—2018年进行了田间药效试验.2年试验结果表明,27％肟菌酯·戊唑醇悬浮剂(135～225 g/hm2)对花生叶斑病的防效均在90.96％以上,显著高于对照药剂430 g/L戊唑醇悬浮剂、50％肟菌酯水分散粒剂、50％多菌灵可湿性粉剂,对花生安全无药害,可以作为防治花生叶斑病的有效药剂使用.

为了明确葡萄园绿盲蝽田间种群的抗药性,采用试管药膜法测定了噻虫胺、高效氯氰菊酯、毒死蜱、阿维菌素、吡虫啉对山东省烟台市不同地区绿盲蝽种群的室内毒力.结果 表明:噻虫胺对烟台地区绿盲蝽的毒力最高,阿维菌素次之,再次为吡虫啉和高效氯氰菊酯,毒死蜱对烟台地区绿盲蝽的毒力最低;烟台市不同地区绿盲蝽种群对供试药剂的敏感性差异较小,而福山地区的绿盲蝽种群对各供试药剂的敏感性最高,莱山地区的绿盲蝽种群对各供试药剂的敏感性最低.

为建立快捷、灵敏检测苹果轮纹病菌Botryosphaeria dothidea的环介导等温扩增(loop-mediated isothermal amplification,LAMP)检测方法,以其内转录间隔区ITS序列为靶标,设计6条LAMP引物,对其特异性进行检测,优化反应条件并建立苹果轮纹病菌的LAMP检测方法.引物特异性检测结果表明,2株苹果轮纹病菌反应结果呈绿色为阳性,而其它3株对照菌株反应结果呈橙色为阴性,表明了LAMP检测引物的高特异性.优化后的LAMP最佳反应条件:温度65℃、扩增时间60 min、FIP/BIP、F3/B3、LF/LB引物终浓度分别为1.0、0.25、0.5 μmol/L.LAMP检测方法对苹果轮纹病菌DNA的检测灵敏度达到了100 ag/μL,是常规PCR检测灵敏度的100倍.田间疑似轮纹病组织检测结果发现LAMP方法对苹果轮纹病菌的检出率高达68％,而传统分离鉴定方法的检出率仅为24％.表明所建立的苹果轮纹病菌LAMP快速检测方法简便快捷、特异性好、灵敏度高,尤其适用于基层植保机构对于苹果轮纹病菌的田间快速检测.

The endophytic Bacillus amyloliquefaciens YTB1407 was previously reported to promote the growth of sweet potato (Ipomoea batatas cv. Yanshu 25). Here, we demonstrate in both in vitro and pot trial assays that pre-treatment with YTB1407 suspension could enhance resistance against root rot disease and black rot disease, caused by Fusarium solani Mart. Sacc. f. sp. batatas McClure and Ceratocystis fimbriata Ell. & Halst on sweet potato, respectively. When seedlings were infected with fungal pathogens at 10 days post irrigation, pre-treatment with YTB1407 suspension decreased these pathogens and YTB1407 bacterial biomass in sweet potato roots. The pre-treatment activated the expression of salicylic acid (SA)-responsive PR-1 gene, raised SA content, and reduced hydrogen peroxide (H2O2) in the host to resist F. solani, while it enhanced the expression levels of SA-responsive NPR1 and PR1 genes and increased SA content to resist C. fimbriata. The disease resistance control effect initiated by pre-treatment with YTB1407 for root rot pathogen (F. solani) was better than for black rot pathogen (C. fimbriata). The results indicated that Bacillus amyloliquefaciens YTB1407 played a pivotal role in enhancing resistance to two fungi pathogens in sweet potato, through production of some antifungal metabolites to decrease infection in the early stage as well as induction of SA-dependent systemic resistance.

为明确35％氯氟醚菌唑悬浮剂对苹果褐斑病的田间防治效果,2018-2019年进行了药效试验.结果 表明,35％氯氟醚菌唑悬浮剂对苹果褐斑病具有良好的防治效果,持效期长,末次喷药后20d,其5000、3 500、2 500倍液3个处理防效仍在97.50％以上,极显著优于对照药剂25％丙环唑水乳剂2 500倍液.在推荐剂量下对苹果树安全无药害,可以作为防治苹果褐斑病的有效药剂推广,在苹果褐斑病发生前或初期使用,对苹果树全株均匀喷雾.

[目的]为明确4种植物源杀虫剂对苹果黄蚜的防治效果及其对天敌的安全性.[方法]采用喷雾法测试不同剂量5％鱼藤酮可溶液剂、1.5％除虫菊素水乳剂、0.5％苦参碱水乳剂、1％蛇床子素微乳剂对苹果黄蚜的田间控制效果,同时调查高浓度杀虫剂对捕食性天敌瓢虫幼虫数量的影响.[结果]5％鱼藤酮可溶液剂对苹果黄蚜防效最佳,药后14 d防效在94.54％以上,其他3种植物源杀虫剂的高、中剂量对苹果黄蚜亦具有较好防治效果,药后14 d防效在77.76％～87.01％,均显著优于常用化学药剂吡虫啉,且4种植物源杀虫剂对苹果黄蚜捕食性天敌瓢虫具有较好的安全性.[结论]建议在苹果黄蚜发生初期轮流、交替使用植物源杀虫剂,以延缓害虫抗药性的发生发展.

[目的]为明确9.5％溴虫氟苯双酰胺悬浮剂对甘蓝主要害虫小菜蛾、菜青虫的防治效果.[方法]2018、2019年于山东烟台进行了田间药效试验.[结果]9.5％溴虫氟苯双酰胺悬浮剂15、20、24 g a.i./hm2,药后7 d对甘蓝小菜蛾、菜青虫防效分别达90.79％、92.76％以上,防效随着剂量的增加而加强.[结论]9.5％溴虫氟苯双酰胺悬浮剂可作为防治甘蓝小菜蛾和菜青虫的高效理想药剂,具有较好的应用前景.

旧的]评价11％戊唑醇·环氟菌胺悬浮剂对黄瓜白粉病的田间防效.[方法]2016-2017年喷雾法于山东省海阳市进行了田间药效试验.[结果]11％戊唑醇·环氟菌胺悬浮剂33～66 g a.i./hm2对黄瓜白粉病防效显著,药后9d防效为88.15％～92.84％,末次药后11d防效为89.75％～94.86％,优于或相当于对照药剂430g/L戊唑醇悬浮剂、10％环氟菌胺悬浮剂.[结论]11％戊唑醇·环氟菌胺悬浮剂可作为防治黄瓜白粉病的理想药剂之一在生产中应用.

采用菌丝生长速率法测定了山东省胶东地区52株葡萄白腐病菌Coniella diplodiella对吡唑醚菌酯的敏感性,检测了水杨肟酸(SHAM)对葡萄白腐病菌菌丝生长及其对吡唑醚菌酯敏感性的影响,并通过室内毒力测定及田间防效试验比较了吡唑醚菌酯与其他4种不同作用机制药剂的毒力.结果显示:添加SHAM(20μg/mL)能够显著提高葡萄白腐病菌对吡唑醚菌酯的敏感性(F=5.5017,P=0.0388),与吡唑醚菌酯单独作用相比,添加SHAM后吡唑醚菌酯对葡萄白腐病菌的毒力提高了1.17倍.供试葡萄白腐病菌对吡唑醚菌酯整体仍表现为敏感,EC50值在0.176～6.012μg/mL之间,平均值为(2.826±1.670)μg/mL,其敏感性频率分布呈连续单峰曲线,且符合正态分布,因此可将该EC50平均值(2.826±1.670)μg/mL作为山东省胶东地区葡萄白腐病菌对吡唑醚菌酯的相对敏感基线.戊唑醇、福美双、代森锰锌及多菌灵对葡萄白腐病菌的EC50值分别在0.364～16.873、5.236～25.562、15.912～84.778和1.819～568.690μg/mL之间,葡萄白腐病菌对吡唑醚菌酯的敏感性与对戊唑醇的相当,显著高于对福美双、代森锰锌和多菌灵的敏感性.研究结果可为田间防控葡萄白腐病的药剂选择及合理轮换使用提供理论依据.