江苏省域草莓灰霉病菌种群多药剂抗性检测

本研究旨在阐明江苏省草莓主产区草莓灰霉病菌种群对常用杀菌剂的敏感性。采用区分剂量法测定了2019和2020年采集的236株草莓灰霉病菌(Botrytis cinerea)对13种杀菌剂的抗性,并对菌株抗性频率和多药剂抗性进行了分析。结果表明:所有灰霉菌株对咯菌腈(fludioxonil,Flu)表现敏感,而对多菌灵(carbendazim,Car)、吡唑醚菌酯(pyraclostrobin,Pyra)、扑海因(iprodione,Ipr)、腐霉利(procymidone,Pro)、嘧霉胺(pyrimethanil,Pyr)产生了较高的抗药性,其抗性频率分别为58.05%、55.01%、51.44%、45.80%、33.94%;灰霉病菌种群在地区间对不同药剂的抗药性水平不同,溧水、昆山、姜堰、铜山田间以抗性菌株为优势种群,无锡和常州新北地区以敏感菌株为主;本研究在区分计量浓度下,根据各药剂抑菌率分布状况,将供试药剂分为敏感药剂、敏感性下降药剂和抗性药剂3种类型;本研究共检测到9种抗药性类型:Pyra^(R)(7.32%)、Car^(R)(6.50%)、Pyr^(R)(0.81%)、Car^(R) Pyr^(R)(3.25%)、Car^(R) Pyra^(R)(14.63%)、Car^(R) Bos^(R)(1.63%)、Car^(R) Pyra^(R) Pyr^(R)(23.58%)、Car^(R) Bos^(R) Pyra^(R)(7.31%)、Car^(R) Bos^(R) Pyra^(R) Pyr^(R)(34.15%)。江苏省草莓灰霉病菌种群对多菌灵和吡唑醚菌酯基本丧失了敏感性,对扑海因、腐霉利、啶酰菌胺、戊唑醇等敏感性下降,多药剂抗药性种群以Car^(R) Pyra^(R) Pyr^(R)和Car^(R) Bos^(R) Pyra^(R) Pyr^(R)为主,抗性治理措施中推荐使用不同类型药剂交替防治灰霉病。

SYNTHESIS AND DRUG RELEASE OF CROSSLINKING POLYPHOSPHATES

A new class of crosslinking polyphosphates were synthesized characterizedby IR 1HNMR, 31PNMR spectroscopy as well as elemental analysis. In vitrodegradation of the polyphosphates obtained and the release of antineoplastic drugMethotrexate (MTX) and contraceptive Levonorgestrel (LNG ) by nsing thesepolymers as matrix were studied. Zero order release rate was rkserved in the case ofLNG release.

Endophytes from medicinal plants and their potential for producing indole acetic acid, improving seed germination and mitigating oxidative stress

Medicinal plants have been used by marginal communities to treat various ailments. However, the potential of endophytes within these bio-prospective medicinal plants remains unknown. The present study elucidates the endophytic diversity of medicinal plants（Caralluma acutangula, Rhazya stricta, and Moringa peregrina） and the endophyte role in seed growth and oxidative stress. Various organs of medicinal plants yielded ten endophytes, which were identified as Phoma sp.（6 isolates）, Alternaria sp.（2）, Bipolaris sp.（1）, and Cladosporium sp.（1） based on 18 S rD NA sequencing and phylogenetic analysis. The culture filtrates（CFs; 25%, 50%, and 100% concentrations） from these endophytes were tested against the growth of normal and dwarf mutant rice lines. Endophytic CF exhibited dose-dependent growth stimulation and suppression effects. CF（100%） of Phoma sp. significantly increased rice seed germination and growth compared to controls and other endophytes. This growth-promoting effect was due to the presence of indole acetic acid in endophytic CF. The gas chromatography/mass spectrometry（GC/MS） analysis showed the highest indole acetic acid content（（54.31±0.21） μmol/L） in Bipolaris sp. In addition, the isolate of Bipolaris sp. exhibited significantly higher radical scavenging and anti-lipid peroxidation activity than the other isolates. Bipolaris sp. and Phoma sp. also exhibited significantly higher flavonoid and phenolic contents. The medicinal plants exhibited the presence of bio-prospective endophytic strains, which could be used for the improvement of crop growth and the mitigation of oxidative stresses.