Effect of Completion of Vernalization on Generative Development of Winter Rape (Brassica napus L. var. oleifera) Plants     

W. Filek  F. Dubert 《Journal of Agronomy and Crop Science》1994,172(1):29-37

Germinating seeds and young plants of winter rape var. Górczañski were vernalized for 56–63 days under conditions of 9-hour day, at the temperature 2 and 5 °C and in continuous darkness at the temperature 2 °C. After vernalization the plants grew under conditions enabling to complete vernalization: in a glass-house at the temperature day/night 15/10 °C and in semi natural conditions of open vegetation hall in the period from June till August. After sub-optimal vernalization further growth of the plants at lowered temperature increased its effectiveness (completion of vernalization). Depending on the degree of the vernalization of the plants the completion of their vernalization was both obligatory, i.e. conditioning the acquisition of the ability of generative development, and facultative i.e. accelerating this development. It has been demonstrated that the population of plants of the examined variety is strongly differentiated not only with respect of vernalization requirements in the particular plants, but also what regards the effectiveness of vernalization completion. New observations have been made indicating that the mechanisms controlling the successive phases of generative development, i.e. phase of forming flower buds and the flowering phase are not identical which may be interpreted as indicating that the "flowering factor" is polymorphous.  相似文献   

Issues and Some Strategies of Sustainable Development of Black Soil Resources in Black Soil Zone in Northeast China     

贾利 《勤云标准版测试》2005,(4)

黑土资源是世界的稀缺资源,黑土带的水土流失、环境污染、土地流转、土地退化问题成为黑土资源可持续发展的障碍。根据实地调研结合资料,分析了东北黑土带土地资源可持续发展的主要问题;提出了黑土资源的可持续发展对策,即:加强农业发展规划;保护黑土区耕地,农耕技术上改进,加强农田基本建设等。  相似文献   

学会改革与发展面临的问题及对策     

安凯春 《勤云标准版测试》2005,(7)

随着社会主义经济体制的逐步完善,改革的不断深化和对外开放的进一步扩大,学会在组织体制、管理模式、运行机制和活动方式等方面,还不能完全适应社会主义市场经济的要求,在综合分析学会存在诸多问题以及面临激烈竞争和严峻挑战的基础上,针对农业学会目前现状,提出了对策,以及今后努力发展的方向。  相似文献   

渠道水力最优断面的程序设计及绘图   总被引：1，自引：0，他引：1  

欧建锋  骆进军 《节水灌溉》2001,1(2):10-11

利用ActiveX Automation技术将Visual BASIC与AutoCAD链接，实现了常用渠道的水力最优断面设计及绘图的自动化，可明显提高渠道设计及绘图的工作效率。  相似文献   

江西苎麻产业化发展的思考与探讨     

汪剑鸣孙学兵  李海龙 《中国麻业》2004,26(1):35-39,30

本文分析了江西苎麻业的发展现状和机遇，指出了江西苎麻业所面临的各种挑战，并提出了相关发展对策。  相似文献   

贵州省林业行政案件发生的主要原因分析及对策探讨   总被引：3，自引：0，他引：3  

钟黔春 《林业资源管理》2006,(1):16-19

对贵州省“十五”林业行政案件发生的原因进行了认真分析,并就进一步加强和改进森林资源保护管理及林业行政执法工作进行了初步探讨。  相似文献   

贵州省退耕还林与农村经济发展研究     

赵华 《林业调查规划》2004,29(1):57-60

通过对贵州省贞丰、桐梓、锦屏等若干县市林业生态建设监理、检查、造林实绩核查等工作的实践和研究，认为退耕还林工程与农村经济发展相结合，目前应加强以下工作：选择林业主导产业；林产业时间、空间的合理布局；树种、林种的结构优化；林业体制创新；实施相关配套工程。  相似文献   

Annual sex hormonal profiles, gonad development and age determination of the Mekong giant catfish (Pangasianodon gigas, Chevey)     

A Manosroi  K Meng-umphan  & J Manosroi 《Aquaculture Research》2003,34(15):1379-1385

Annual sex hormonal profiles, gonad development and age determination of 18 (13–14 kg body weight) and three (145–226 kg body weight) Mekong giant catfish (MGC) (Pangasianodon gigas, Chevey) reared in earthen ponds in Chiang Mai and from the Mekong River in Chiang Rai, Thailand, respectively, were investigated. The hormonal profiles were determined from blood samples of the fish by electrochemiluminescence immunoassay during May to August in 2000. The highest testosterone levels of 0.06 ng mL^?1 in both sexes and the highest oestradiol of 47.8 and 14.23 pg mL^?1 in females and males, respectively, were observed in May. The gonadosomatic index was found to be 0.07 for males and 0.38 for females from ponds in comparison with 2.27 for males and 8.29 for females from the Mekong River. Higher development stages of spermatocytes and oocytes of the cultured fish in May than in February and November were demonstrated. No mature germ cells were obtained from either the males or females, indicating no sexual maturity. The average age of fish was determined from the annual rings of the cross‐section of the pectoral fins by a stereomicroscope. The average age of fish in earthen pond determined from the annual ring was 8 years, which agreed with the actual culture records, while those from the Mekong River were 21 years. This information will be beneficial for the breeding programmes and conservation of the MGC.  相似文献   

试论发展香菇生产与林木资源的永续利用     

王丽霞 《浙江林业科技》2001,21(4):90-93

就如何解决或缓和袋料香菇生产与木材资源之间的矛盾问题进行了论述，认为应从（1）降低消耗，提高单产，（2）培养新资源；（3）积极开发利用菇木替代资源；4；推广各种节能机械；（5）加强资源管理，（6）建立合理的补偿机制共6个方面采取对策。  相似文献   

薯类加工产业可持续发展的现实思考   总被引：1，自引：0，他引：1  

李伟智 《中国农机化》2004,(2):54-56

就湖南省娄底市农饥部门致力于红薯加工机械与加工技术的研究开发和推广应用的实践，对如何推进特色产业的可持续发展做理性和现实思考。  相似文献