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锈色粒肩天牛发生及防治研究进展 总被引:4,自引:0,他引:4
锈色粒肩天牛是严重为害国槐的蛀干害虫。近年来,该虫发生为害不断扩大和加重,严重影响了城市绿化和市容景观。为此,根据文献资料,对该虫的分布、分类地位、生物学特性、预测预报及防治技术研究进展情况进行了综述。 相似文献
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麦套稻因前期与小麦共生旱长,齐苗期长2~14d,出苗率低36.2%~91.3%,苗质弱,单位长度占有的干物重只及对照的1/3,营养生长滞后,但叶龄进程随生育期推进而明显加快,叶差由苗期的2.2个至拔节期为1.1个,抽穗期仅差2~3d,即总生育天数与总叶片数相当;在器官建成上表现为个体生长不足而群体优势明显,亩成穗数多10.1%~13.1%。而每穗实粒数下降14.1%~22.1%,千粒重差异不大,最终产量差异不一致。试验以生育期适中的穗粒并重型品种、共生期30d左右为宜。 相似文献
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LU WenmingResearch Institute of Forestry Policy Information Chinese Academy of Forestry. Wan Shou Shan. Beijing China 《中国林业科技(英文版)》2002,(2)
The paper elaborates in details certification mechanism for sustainableforest management, including the definition, contents, objectives, costs, benefits, characteristics, procedures and impacts of certification as well as main certification systems. It also introduces in details the latest progress and development perspectives of certification in China and around the world. Certification is a market-based mechanism, which aims at enhancing and strengthening the reasonable utilization offorests. It usually consists of certification for sustainable forest management and certification of COC. Certification costs, including direct costs and indirect costs, but also benefits, which depends on the level of certification outputs. Internationally recognized FSC certification has been widely developed around the world, and a number of international organizations such as the WB and WWF etc are also promoting the process of FSC certification. Certification has bright perspectives of development around the world, 相似文献
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