Flumorph Is a Novel Fungicide That Disrupts Microfilament Organization in Phytophthora melonis

ABSTRACT The mechanism of the effects of flumorph (a novel fungicide) was investigated by analyzing alterations of hyphal morphology, cell wall deposition patterns, F-actin organization, and other organelles in Phytophthora melonis. Calcofluor white staining suggested that flumorph did not inhibit the synthesis of cell wall materials, but disturbed the polar deposition of newly synthesized cell wall materials during cystospore germination and hyphal growth. After exposure to flumorph, zoospores were able to switch into cystospores accompanied with the formation of a cell wall, whereas cystospores failed to induce the isotropic-polar switch and did not produce germ tubes but continued the isotropic growth phase. In flumorph-treated hyphae, the most characteristic change was the development of periodic swelling ("beaded" morphology) and the disruption of tip growth. Newly synthesized cell wall materials were deposited uniformly throughout the diffuse expanded region of hyphae, in contrast to their normal polarized patterns of deposition. These alterations were the result of F-actin disruption, identified with the fluorescein isothiocynate (FITC)-phalloidin staining. The disruption of F-actin also was accompanied by disorganized organelles: each swelling of subapical hyphae was associated with a nucleus. Vesicles did not undergo polarized secretion to the apical hyphae, but diffused around nuclei for the subapical growth; thus, the cell wall was thickened with periodic expansion along the hyphae. Upon removing flumorph, normal tip growth and organized F-actin were observed again. These data, as well as data published earlier, suggest that flumorph may be involved in the impairment of cell polar growth through directly or indirectly disrupting the organization of F-actin. The primary site of action by flumorph in the disruption of the F-actin organization is under investigation.     

南方利用冬闲田种植亚麻的概况及其综合开发利用

随着人们生活质量的提高，环境意识的增强，对环保服装、绿色纺织的需求也日益增长。亚麻织品是以天然原料制成，具有吸湿、透气，穿着挺阔、凉爽、不粘皮肤等优良特性，是其它产品无法替代的，逐渐成为人们喜爱的服装，也迎合了人们崇尚自然的消费潮流。因此对亚麻纤维的需求量逐年增加，种植面积也随之扩大。尤其是我国南方在农业产业结构大调整的情况下，利用抛荒冬闲田种植亚麻，形成了一条产业化道路，既充分利用了光温、土地资源，又增加了农民收入，带动了一个产业。本文就我国南方利用冬闲田种植亚麻的有利条件、概况及综合开发简要…     

出口杨梅农药残留标准与合理用药技术的建议

近年来杨梅出口势头良好,产品已批量销往日本、韩国、欧盟等十几个国家和地区,深受国外消费者的青睐和欢迎。然而,值得关注的是杨梅的安全质量,能否经受住技术性贸易壁垒的考验,从而避免重蹈我国柑橘、草莓等因为农药残留超标而遭进口方扣留之覆辙。为此,本文建议当前杨梅生产应从源头抓起,积极应对出口所面临的技术壁垒,规范杨梅病虫害防治和合理用药。     

流动沙丘沙埋对沙柳生长特性的影响

对毛乌素沙地流动沙丘上沙柳的根系分布、冠层特征进行研究.结果表明:沙柳在不同的环境中其生长状况有所差异,沙柳遭流沙掩埋后,被掩埋的枝条发展为根系.且萌发新的不定根,有效的增加了沙柳地下部分的深度、广度和生物量,增强了沙柳根系吸收水分和养分的能力.从而引起地上部分的覆盖面积和生物量较未沙埋沙柳都有了明显的增加.     

端正教育思想 办好农村特色学校

学校要办出各自的特色是《中国教育改革发展纲要》中对中小学教育改革提出的要求,也是当今办学发展的趋势。本文主要阐述了四平市铁东区二龙湖学校的办学理念及提升学校综合办学水平的措施。     

海涂人工植被互花米草的综合开发和利用

互花米草系禾本科米草属多年生草本植物,是继大米草在我国引种成功后从美国引进的又一适宜海滩潮间带生长的耐盐、耐淹植物,其植株高大、粗壮,常有1.5～2米高,且根系发达,地下茎横的伸长扩生新苗,发展迅速,互花米草在我国发展约10多万亩,在台州各市(县)沿海海涂已发展3000多亩形成了草带,并有进一步扩大的趋势。互花米草具有良好的保滩护     

Reflections on the system of evaluation of gene-edited livestock

The rapid development of biotechnology has provided a greater understanding of the biological functions of major candidate genes that have important functions regarding economic traits, and new materials for livestock breeding have been obtained through gene editing (GE) and embryo manipulation with the purpose of improving quality and output and reducing the costs and risk of disease. Public concerns, particularly over safety risks and production performance, must be addressed. Evaluation is the most important component of the regulation of gene-edited livestock and is a crucial guarantee of public safety before the marketing of gene-edited animal products. Here, the system of evaluation of gene-edited livestock is discussed in terms of public safety and production performance. The search for safe and ethical applications in the GE of livestock, a case-by-case evaluation strategy, and classification and simplification are used in order to promote a more efficient, objective, comprehensive and operable evaluation system.     

当前肉牛杂交生产中存在的问题及其对策

对肉牛生产基地的深入调查研究，发现目前肉牛杂交生产中存在一些值得注意的问题，并根据杂交理论与实践提出了对该问题的看法和建议。