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21.
Activators of sesquiterpene synthase (STS) gene expression and sesquiterpene production in Piper betle L. were examined using quantitative real time PCR and gas chromatography mass spectrometry methods, and the allelopathic activity of untreated and Fusarium solani-treated betel extracts was tested on seed germination and on the shoot and root growth of Thai rice variety PSL2 (Oryza sativa cv. Phitsanulok 2) and three dominant paddy weeds (Eclipta prostrata, Echinochloa crus-galli and Chloris barbata). The results demonstrated that F. solani dramatically upregulated STS expression and productions of β-cubebene, β-caryophyllene and germacrene D sesquiterpene when compared with the untreated control, and that betel extracts had a greater inhibitory effect on weeds than on rice. The effects were more clearly detected on seed germination and root growth than on shoot growth, and they were found to be dose-dependent. It is also noted that F. solani-treated extract had stronger effects than the untreated extract. The species most sensitive to the allelopathic effects was C. barbata, germination of which was completely inhibited even at a dose of 0.1 mg/mL untreated extract. With regards to rice, although betel extract at 1.0 mg/mL showed no inhibition on germination, it affected the elongation of rice roots, in addition to those of the tested weeds. The obtained data suggested that F. solani has potential as an activator of sesquiterpene allelochemical production via STS expression, the latter leading to the treated betel extract having a stronger phytotoxic effect. These results were beneficial in the promotion of natural herbicide production using biotechnology.  相似文献   
22.
综述了盐土农业新理念的产生、定义、特点及其国内外研究进展。  相似文献   
23.
肌细胞增强因子2B(MEF2B)基因属于肌细胞增强因子2(MEF2)基因家族成员,广泛表达于人和动物的肌肉和神经组织中,在肌肉生成、神经系统发育和分化、肝脏纤维化等方面具有重要的作用,作者从MEF2B基因的结构、组织分布、生物学功能及研究进展等方面对该基因进行了综述.  相似文献   
24.
Integrated pest management (IPM) is facing both external and internal challenges. External challenges include increasing needs to manage pests (pathogens, animal pests and weeds) due to climate change, evolution of pesticide resistance as well as virulence matching host resistance. The complexity of designing effective pest management strategies, which rely less heavily on the use of conventional pesticides, is another external challenge. Internal challenges include organizational aspects such as decreasing trend in budget allocated to IPM research, increasing scarcity of human expertise, lack of knowledge transfer into practice and the communication gap both at country level and between countries, and lack of multi-, inter- and transdisciplinary IPM research. There is an increasing awareness that trans-national networking is one means to overcome such challenges and to address common priorities in agriculture. A large number of stakeholders (researchers, policy makers, growers and industries) are involved in the sector of crop protection, which needs to be coordinated through effective communications and dynamic collaboration to make any IPM strategy successful. Here we discuss a decade-long IPM networking experiences in Europe emphasizing how IPM research, implementation and adoption in Europe may benefit from a broader level networking.  相似文献   
25.
以安庆职业技术学院为例,通过对苏州、合肥等地的兄弟院校、企事业单位进行走访,就都市园艺专业发展前景、人才培养的定位、实施意见与专业建设进行了交流.通过完善人才培养体系,提升学生专业技能,带动地方产业发展.  相似文献   
26.
《农业科学与技术》2013,(10):1468-1470,1485
The development of microbial herbicide for weed control has been serious- ly regarded all over the world and has made rapid progress in recent years. This paper presents a comprehensive review on domestic and abroad research progress of microbial herbicide and mainly introduces the microbial herbicide products and mi- crobial sources with commercialization potential, and then proposes an outlook for their development tendency and application prospect.  相似文献   
27.
针对红萍营养丰富、适口性好、可作为某些畜禽饲料的特点,梳理总结我国多年来红萍作为鱼、猪、牛、鸡、鸭以及其它动物饲料应用等方面的研究,并对今后红萍饲用研究的内容及方向提出建议。  相似文献   
28.
批次化生产是欧美等畜牧业发达国家开发的一种工厂化养猪模式,近年来我国也在逐渐推广应用,它显著提升了猪场生产效率与生物安全,尤其对当前我国非洲猪瘟防控和生猪产能恢复具有重要意义。文章简述了母猪批次化生产的研发历史,并综述了其技术优势、关键技术以及我国目前研发、应用情况,以期提高我国母猪批次化生产水平,促进养猪业转型升级。  相似文献   
29.
Brans of 23 traditional and 12 improved (both red and white) rice varieties in Sri Lanka were screened for anti-amylase and anti-glycation activities in vitro. Varieties which showed the highest inhibitory activities at screening were further investigated for anti-glucosidase and glycation reversing as anti-diabetic properties. The same varieties were studied for selected antioxidant properties. Significantly high anti-amylase and anti-glycation activities were observed for bran extracts of red varieties compared to white varieties at screening. Traditional red rice varieties, Masuran, Sudu Heeneti, Dik Wee and Goda Heeneti, exhibited significant and dose dependent anti-amylase, anti-glycation and glycation reversing activities. These varieties also showed marked antioxidant properties. It is concluded that brans of Sri Lankan traditional red rice varieties Masuran, Sudu Heeneti, Dik Wee and Goda Heeneti may be potential food supplements for diabetes.  相似文献   
30.
《保鲜与加工》1997,(6):7-14
This paper discusses practical methods of investment risk analysis at a construction project,applying the Xifang Economics Principle and the Mathematical statistics etc, It has reference value for improving the Feasibility Research(FR)and Investment Decisions.  相似文献   
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