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排序方式： 共有1759条查询结果，搜索用时 28 毫秒
1.
Alfonso D. Victoria Arellano Emanueli B. Furtado Tailine M. Holz Paulo C. Pazdiora Gustavo M. da Silva Emerson M. Del Ponte Leandro J. Dallagnol 《Plant pathology》2022,71(5):1056-1065
Italian ryegrass is a major pasture crop cultivated mainly for feeding cattle in southern Brazil. The choice of crop is based on nutritional quality and the shortage of pastures that occur during the winter in the southernmost part of Brazil. In this region, the production of biomass and seeds are threatened by diseases, in particular fungal diseases that affect the foliage. In this study we identified and monitored the natural occurrence of a complex of leaf spotting diseases and evaluated the effects of combined management practices to reduce the intensity of foliar diseases: seed treatment with Trichoderma atroviride, soil amendment with silicon and cutting frequency (none, one or two cuts). Three diseases were present in a two-season experiment: grey leaf spot (Pyricularia oryzae), brown leaf spot (Bipolaris sorokiniana) and parrot's eye leaf spot (Cercospora sp.). Grey leaf spot had the highest severity, regardless of treatment, during the first season, and was the only disease present in the following season. Grey leaf spot dominated, and plants receiving only one cut were more prone to P. oryzae infection. The treatments with silicon or T. atroviride reduced the relative disease by 40% to 80%, in relation to untreated and uncut regimes. This study showed the main leaf spot diseases associated with L. multiflorum. Moreover, it demonstrates for the first time in the region the effectiveness of reducing leaf spot via the application of silicon in the soil, inoculation of seeds with T. atroviride and managing the cutting regime. 相似文献
2.
里氏木霉产纤维素酶的研究及其应用进展 总被引：2，自引：0，他引：2
有机碳是加快驱动氮循环的最主要物质之一,协助降解养殖水环境中的有毒氮污染,是维护养殖水环境的重要物质。地球上分布最广、蕴藏量最丰富的可再生资源之一是纤维素,而纤维素酶能降解纤维素的β-14-葡萄糖苷键以生成葡萄糖或其他可溶性糖,可以作为水产养殖所用的有机碳。研究表明,里氏木霉（Trichoderma reesei）所分泌的纤维素酶具有产酶量高、稳定性好、适应性强等优点,是目前应用最为广泛的纤维素酶。文章综述了里氏木霉所产纤维素酶的结构、组分及酶活机制,介绍了里氏木霉菌种人工选育及基因工程改造等研究,展望了纤维素酶在食品、纺织、饲料、农业等多种行业的应用。 相似文献
3.
阐述了农业院校大学生人文素质素质教育的特殊意义,总结了农业院校大学生人文素质教育面临的教育环境、教育主体、教育客体等特殊问题,指出加强农业院校大学生人文素质教育的途径,包括增强教职工的人文素质教育意识,优化课程设置,构建特色校园文化,加强社会实践活动. 相似文献
4.
猕猴桃全光喷雾扦插快速育苗研究 总被引：1，自引：0，他引：1
用中华猕猴桃(Actindia chinensis Planch.)‘江西79—1’、‘79—3’、‘奉新79—2’于6月中旬进行嫩枝全光喷雾扦插,苗床温度为25—30℃,叶面相对湿度为85%以上,以蛭石为扦插基质,插条基部用1000ppm吲哚丁酸进行速蘸(30秒)处理。试验结果插条发根率77.1%。插后5天产生愈伤组织,20天生根 40天移栽时单株平均根数为11.8条,平均根长6.9cm,最多根数35条,最长根17.9cm;移栽成活率85%以上。移栽苗当年新梢长2—10cm,第2年枝蔓平均长49.7cm,最长蔓137cm。 相似文献
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6.
技术、文化与经济相结合,建立海岸城市生态安全,提高人居舒适度的最佳森林结构为基础;以森林文化与海洋文化、雕塑艺术、服饰文化、园林文化等多种资源整合形成具有鲜明地域性森林文化为其文化内涵;以循环经济为环境支撑。本文将从技术、文化、经济三方面来探讨海湾型森林城最佳模式。
相似文献
7.
\"问我祖先来何处,山西洪洞大槐树。\"\"祖先故居叫什么,大槐树下老鹳窝。\"这首民谣在我国广大地区流传了600百余年,祖辈相传,妇幼皆知。 相似文献
8.
K. David Hyrenbach Zora McGinnis Kathleen Page Dan Rapp F. David Horgen Jennifer M. Lynch 《水产资源保护:海洋与淡水生态系统》2021,31(2):408-419
- Although the frequency of occurrence of plastic ingestion in the large-sized dolphinfish and tunas taken by the Hawai'i longline fishery is very low (frequency of occurrence < 5% of sampled individuals), the ingestion of plastic in smaller-sized specimens caught with pole-and-line gear by commercial and recreational fishers has not been investigated.
- This study examined ingestion of >0.25 mm marine plastic debris (MPD) by four predatory fish species caught by commercial fishers around the Main Hawaiian Islands, and documented ingestion in three species: 85.7% of albacore tuna (n = 7), 40.0% of skipjack tuna (n = 10) and 12.5% of dolphinfish (n = 8).
- Yellowfin tuna (n = 10) did not contain any MPD, probably owing to the high proportion of empty stomachs (60%).
- For skipjack tuna, the frequency of occurrence of MPD ingestion was significantly higher for the smaller-sized specimens caught with pole-and-line (40%), compared with the larger-sized specimens caught with longlines (0%).
- For dolphinfish, the frequency of occurrence of MPD ingestion was similar for the similar-sized specimens caught with pole-and-line and with longlines.
- The ingested MPD items were micro–meso plastics, between 1 and 25 mm. While most ingested items were fragments, albacore also ingested line and skipjack also ingested sheets.
- The predatory fishes ingested light MPD items that float in sea water, but there were species-specific differences in their polymer composition: albacore contained more polypropylene and polyethylene, and skipjack contained more elastomers, characterized by a high percentage of ester plasticizers.
- Altogether, these results suggest that albacore and skipjack tunas ingest plastic of different types and polymers. Yet more research is needed to understand how differences in vertical distribution, foraging ecology and diet influence the MPD sampled by these predatory fish species.
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