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摘要:为了明确红阳猕猴桃褐斑病主要病原菌及适宜的防治药剂,采集贵州省水城区红阳猕猴桃褐斑病的标样,通过组织分离、纯化,致病性检测,形态学观察,分子检测及系统发育分析确定病原菌种类,并采用菌丝生长速率法测定6种药剂对该病原菌生长的抑菌效果。结果显示:分离纯化得到的病原菌的形态特[收稿日期:
基金项目:贵州省科研机构创新能力建设项目(黔科合服企[2019]4004);贵州科学院青年基金(黔科院J字[2021]21号);贵州省科技计划项目(黔科合支撑[2021]一般234)
作者简介:苏文文(1992-),女,河南灵宝人,硕士,主要从事植物病理学研究。E-mail:275272042@qq.com;*为通讯作者:李苇洁,女,研究员,硕士,主要从事猕猴桃栽培和育种研究,E-mail:lwj024333@163.com]征与多主棒孢菌(Corynespora cassiicola)形态特征相似,将分离菌株rDNA–ITS序列与GenBank中相关菌株的ITS序列进行同源性比对,发现该菌株与黄瓜多主棒孢霉菌的相似性达到96%以上。室内药剂筛选结果表明:50%多菌灵可湿性粉剂对病原菌的抑制效果最好,最低浓度可抑制菌丝生长,其次为40%戊唑醇悬浮剂、80%乙蒜素乳油、30%吡唑嘧菌酯乳油和80%代森锰锌可湿性粉剂的抑菌效果较好,EC50分别为0.0002 mg/L、 0.0743 mg/L、0.0871 mg/L和0.5025mg/L。红阳猕猴桃褐斑病主要由多主棒孢菌(Corynespora cassiicola)侵染引起,以上5种药剂均可作为防治红阳猕猴桃褐斑病的有效药剂。 相似文献
94.
海岸风口基干林带修复除木麻黄(Casuarina equisetifolia)外尚无可替代树种,选择抗性优良的木麻黄品系是基干林带修复的关键环节.通过对"惠-1"木麻黄、圆头木麻黄、千头木麻黄、铺地木麻黄等4个品系进行造林和抗风试验,比较几个品系在风口最前沿、近风口的生长和抗风表现,结果表明:风口基干林带修复采用"惠 ... 相似文献
95.
母语迁移对英语学习的影响及教学对策 总被引:3,自引:0,他引:3
语言迁移问题表现在母语对英语学习的正迁移作用和负迁移作用两种。运用对比法针对英语教学活动中出现的语言迁移现象进行分析并提出具体的解决方法:强调母语与英语的异同点,培养学生正确学习英语的习惯;发挥母语的桥梁作用,促进学生对英语知识的理解和掌握。英语教师应在教学活动中积极地运用正迁移、巧妙利用负迁移作用,提高学生的英语学习效果。 相似文献
96.
Many rice-growing areas are affected by high concentrations of arsenic(As). Rice varieties that prevent As uptake and/or accumulation can mitigate As threats to human health. Genomic selection is known to facilitate rapid selection of superior genotypes for complex traits. We explored the predictive ability(PA) of genomic prediction with single-environment models, accounting or not for trait-specific markers, multi-environment models, and multi-trait and multi-environment models, using the genotypic(1600 K SNPs) and phenotypic(grain As content, grain yield and days to flowering) data of the Bengal and Assam Aus Panel. Under the base-line single-environment model, PA of up to 0.707 and 0.654 was obtained for grain yield and grain As content, respectively; the three prediction methods(Bayesian Lasso, genomic best linear unbiased prediction and reproducing kernel Hilbert spaces) were considered to perform similarly, and marker selection based on linkage disequilibrium allowed to reduce the number of SNP to 17 K, without negative effect on PA of genomic predictions. Single-environment models giving distinct weight to trait-specific markers in the genomic relationship matrix outperformed the base-line models up to 32%. Multi-environment models, accounting for genotype × environment interactions, and multi-trait and multi-environment models outperformed the base-line models by up to 47% and 61%, respectively. Among the multi-trait and multi-environment models, the Bayesian multi-output regressor stacking function obtained the highest predictive ability(0.831 for grain As) with much higher efficiency for computing time. These findings pave the way for breeding for As-tolerance in the progenies of biparental crosses involving members of the Bengal and Assam Aus Panel. Genomic prediction can also be applied to breeding for other complex traits under multiple environments. 相似文献
97.
在当前智慧农业的大环境下,农作物生长过程的识别与监控问题一直是一项具有挑战性的任务,基于此提出一种基于物联网的远程温室视觉监控系统,系统通过LoRa无线通信技术监测温室内的温湿度、光照强度等环境参数,能够及时监测到农作物的生长状况,并实现自动通风、自动补光等功能。在PC端的Qt上位机实时监测温室内的环境信息并控制环境参数,通过OV9726摄像头对农作物进行监测,所获得的生长状态信息传输到S3C6410集中控制模块进行处理,结合克隆选择算法和朴素贝叶斯分类器对叶片进行识别处理。本系统采用LoRa模块进行自组网来实现环境监测,将Linux操作系统移植到集中控制模块,为视觉系统软硬件平台的搭建做准备工作,所使用的组合算法能够使得农作物叶片识别率达到95.3%,识别时间达到8.4 ms,对于叶片识别精度等方面有着明显的提升,经过实验充分验证本系统所使用的设备与算法的有效性。 相似文献
98.
Yasmin Vasques Berchembrock Ulisses José de Figueiredo José Airton Rodrigues Nunes Cacilda Borges do Valle Sanzio Carvalho Lima Barrios 《Grass and Forage Science》2020,75(2):145-152
Hybridization in the Urochloa humidicola breeding programme allowed to explore the genetic variability of the apomictic sources and, thus, to obtain new sexual and apomictic parents with compatible ploidy and/or superior progenies. However, given the high variability arising from crosses, there is a need to adopt efficient selection strategies among and within progenies. The aim of this study was to compare the selection methods among U. humidicola progenies with (t-BLUP) and without (BLUP) the weighting based on prediction error and subsequent selection within progenies by individual simulated (BLUPIS) or optimal individual BLUP. We evaluated seventy-one U. humidicola full-sib progenies from biparental crosses between nine sexual and ten apomictic parents. The experiment was set up in an incomplete block design with 64 blocks of 15 plots each, consisting of individual plants. Seven consecutive cuts were made and the traits total dry-matter, leaf dry-matter and regrowth scores were measured. Genetic variance was expressive for all traits. The selection procedure among progenies of U. humidicula based on t-BLUP proved to be more advantageous regarding the use of BLUP not weighted by the prediction error, resulting in higher selection gains, taking as reference the optimal procedure of the individual BLUP. Furthermore, the use of BLUPIS allowed an optimized selection of hybrids, allowing the breeder to explore with variable selection intensity the genetic variability within the selected full-sib progenies based on relative genetic merit. 相似文献
99.
Development and identification of glyphosate-tolerant transgenic soybean via direct selection with glyphosate 下载免费PDF全文
GUO Bing-fu HONG Hui-long HAN Jia-nan ZHANG Li-juan LIU Zhang-xiong GUO Yong QIU Li-juan 《农业科学学报》2020,19(5):1186-1196
Glyphosate-tolerant soybean is the most widely planted genetically modified crop worldwide. However, soybean remains recalcitrant to routine transformation because of the low infection efficiency of Agrobacterium to soybean and lack of useful selectable markers. In this study, several Agrobacterium strains and cell densities were compared by transient expression of the GUS gene. The results showed that Agrobacterium strain Ag10 at cell densities of OD_(600) of 0.6–0.9 yielded the highest infection efficiency in Agrobacterium-mediated soybean cotyledonary node transformation system. Meanwhile, a simple and rapid method was developed for identification of glyphosate tolerance in putative T_0 transgenic plants, consisting of spotting plantlets with 1 μL Roundup~?. The whole cycle of genetic transformation could be shortened to about 3 mon by highly efficient selection with glyphosate during the transformation process and application of the spot assay in putative T_0 transgenic plantlets. The transformation frequency ranged from 2.9 to 5.6%. This study provides an improved protocol for development and identification of glyphosate-tolerant transgenic soybeans. 相似文献
100.
海氏桨角蚜小蜂Eretmocerus hayati是烟粉虱Bemisia tabaci的优势寄生蜂,了解寄生蜂的交配行为有利于完善其规模化繁殖技术。通过对海氏桨角蚜小蜂的首次交配及再次交配、配偶选择等行为学观察,以及多次交配对雌蜂繁殖量影响的生物学试验,明确了该蜂的交配过程包括求偶、交尾前期、交尾和交尾后期;雌蜂在整个生活史中未观察到再次交配;雄蜂可在首次交配后迅速进行再次交配,首次交配后1 h内的再次交配率为83.3%,62.5%的个体可在2 h内完成第3次交配,再次交配的行为持续时间显著低于首次交配;雄蜂的交配次数对自身寿命及其配偶的寄生量无显著影响;此外,在配偶选择中,处女蜂倾向于接受有交配经历的雄蜂,多头雄蜂间存在竞争行为进而干扰交配成功率。 相似文献