The benefits of herbicide-resistant crops

Since 1996, genetically modified herbicide-resistant crops, primarily glyphosate-resistant soybean, corn, cotton and canola, have helped to revolutionize weed management and have become an important tool in crop production practices. Glyphosate-resistant crops have enabled the implementation of weed management practices that have improved yield and profitability while better protecting the environment. Growers have recognized their benefits and have made glyphosate-resistant crops the most rapidly adopted technology in the history of agriculture. Weed management systems with glyphosate-resistant crops have often relied on glyphosate alone, have been easy to use and have been effective, economical and more environmentally friendly than the systems they have replaced. Glyphosate has worked extremely well in controlling weeds in glyphosate-resistant crops for more than a decade, but some key weeds have evolved resistance, and using glyphosate alone has proved unsustainable. Now, growers need to renew their weed management practices and use glyphosate with other cultural, mechanical and herbicide options in integrated systems. New multiple-herbicide-resistant crops with resistance to glyphosate and other herbicides will expand the utility of existing herbicide technologies and will be an important component of future weed management systems that help to sustain the current benefits of high-efficiency and high-production agriculture. Copyright © 2012 Society of Chemical Industry     

金寨县农机专业合作社发展现状及建议

阐述了金寨县农机专业合作社发展的现状,总结了其建设的主要做法,分析了取得的成效及存在的问题,并提出发展建议,以期为金寨县农机专业合作社发展提供参考。     

核桃栽培技术

核桃原产于中亚地带,栽培管理比鲜果类管理、储藏、保鲜相对比较容易,果农一般可采取粗放管理。     

Monensin might protect Ontario, Canada dairy cows from paratuberculosis milk-ELISA positivity

Our objective was to define the role of monensin sodium in protecting cows from being milk-ELISA positive for paratuberculosis in Ontario, Canada dairy herds. In total, 4933 dairy cows from 94 herds were enrolled in this cross-sectional study. Forty-four of the enrolled herds were selected purposively by their herd veterinarian and another 50 herds were randomly selected from a local milk production-recording agency. A herd-management survey was completed on each farm during the months of May through August 2003. During this same time-period, composite milk samples were collected from all lactating cows and tested with a milk-ELISA for antibodies to Mycobacterium avium subspecies paratuberculosis. Analyses were stratified according to the paratuberculosis history of the herds. In the 48 herds in which paratuberculosis had not been diagnosed before, the use of calf hutches and monensin in milking cows were both associated with reduced odds of a cow testing positive (OR = 0.19 and 0.21, respectively). In the 46 herds with a prior history of paratuberculosis, feeding monensin to the breeding-age heifers was associated with decreased odds of a cow testing positive (OR = 0.54). Monensin use might be associated with milk-ELISA positivity, but its impact on the transmission of paratuberculosis remains unknown.     

提高杂交水稻制种母本柱头外露率的栽培技术

提高制种产量的途径不单局限于如何获得充足的花粉量来提高异交结实率这一方面，还应通过栽培措施改善母本生育环境与营养条件来提高母本柱头外露率达到制种高产，本文从育秧、施肥、化学调往栽培角度介绍了提高柱头外露率的技术。     

Impact of agroforestry practices on the flowering phenology of <Emphasis Type="Italic">Vitellaria paradoxa</Emphasis> in parklands in southern Mali

The impact of human practices on the phenology of flowering was assessed for an important agroforestry tree species of the Sudano-Sahelian zone: Vitellaria paradoxa. Flowering was monitored at two sites in southern Mali over 2 years. At each site, the impact of agricultural practices on flowering phenology was assessed by comparing field, fallow and forest. The site effect and agricultural practices were significant for all the monitored variables. The proportion of individuals that flowered was 89% at Koumantou and 40% at MPeresso. About 98, 95 and 75% of individuals at Koumantou and 88, 12 and 20% at MPeresso flowered in the field, fallow and forest, respectively. The mean length of flowering ranged from 69 to 81 days at Koumantou and from 45 to 108 days at MPeresso. The mean number of days for the active phase ranged from 36 to 49 days at Koumantou and from 27 to 64 days at MPeresso. Koumantou’s favourable climatic conditions resulted in better flowering ability and a higher probability of abundant flowering. Field appeared to provide better conditions than fallow and forest regarding flowering ability and probability of abundant flowering. However, tree diameter did not affect flowering phenology. Agricultural practices appear to have a noticeable impact on the phenology of flowering of V. paradoxa. Trees flowered abundantly in the parkland and therefore increased gene flow via pollen and/or seeds and the dynamics of genetic diversity.     

Farmers' perception of environmental degradation and their adoption of improved management practices in Alxa,China

The environment and the natural resource base have been severely degraded in Alxa League, western Inner Mongolia, China, over the past half‐century. This study reports surveys that reveal farmers' perceptions of environmental degradation and their adoption of improved management practices in this poor and remote desert region. Surveys were made in villages that had been engaged in a large environmental rehabilitation and management project [Alxa League environmental rehabilitation and management project (ALERMP)] and those that had not. The survey results showed that farmers perceived environmental degradation in terms of increased frequency and severity of sandstorms, movement of sand dunes, deterioration of pasture quality and declines in groundwater depth and quality. Farmers had low adoption rates for improved management practices, ranging from zero to a maximum of 28·5 per cent for the most adopted practice. A Tobit model analysis showed that the education level of farmers, the availability of extension services and whether farmers had participated in ALERMP were highly significantly correlated with the farmers' perception of degradation. The farmers' adoption of improved management practices was found to be significantly correlated only with whether they had participated in ALERMP. This shows that specific extension activities of the type possible in large and well‐funded projects are required if farmers are to recognise degradation and adopt improved management practices. The promotion of farmer education and strengthening of extension services are recommended as the best policy strategies for improving environmental management in this region. Copyright © 2009 John Wiley & Sons, Ltd.     

云南省玉溪市红塔区现代烟草农业组织管理模式研究

现代烟草农业建设是生产组织、技术和管理的创新,是转变传统烟叶生产方式,促进烟叶生产持续健康发展的过程。文章就玉溪市红塔区现代烟草农业组织管理模式的优势、存在的问题进行了比较并提出了看法;就提高资源利用率、土地流转方式和模式的创新问题展开讨论。     

Sesquiterpenic composition of the inflorescences of Brazilian chamomile (Matricaria recutita L.): Impact of the agricultural practices

Matricaria recutita L. is one of the most common medicinal plants, included in all over the world pharmacopoeias due to, among others, the relevant health benefits of its sesquiterpenic compounds. This paper aims to study the impact of the agricultural practices of M. recutita L. on the occurrence of sesquiterpenic compounds. To fulfill this objective, a methodology that combines the headspace solid phase microextraction (HS-SPME) coupled with one-dimensional gas chromatography-quadrupole mass spectrometry detection (GC-qMS) was implemented. Thirteen populations from different geographic origins, agricultural practices, and harvest times, grown in Santa Catarina and Paraná states, in Brazil, were analyzed. The samples from organic practice showed a tendency to have lower amount of sesquiterpenic compounds than those from the conventional agricultural system. Eleven samples were classified as chemotype B (rich in bisabolol oxide B) and the remaining 2 were classified as chemotype A (rich in bisabolol oxide A). Predominance of chemotype B was observed concerning the agricultural practices (organic or conventional) or geographic origin (Santa Catarina or Paraná). In order to obtain a deeper insight into the sesquiterpenic compounds, comprehensive two-dimensional gas chromatography with time of flight mass spectrometry detection (GC × GC-ToFMS) was also applied, allowing to identify for the first time in chamomile 8 compounds.     

Evaluation ofAmaranthus sp. andVernonia amygdalina, and soil amendments with poultry manure for the management of root-knot nematodes on eggplant

The suppressive effect of vernonia (Vernonia amygdalina), amaranth (Amarathus sp.) and poultry manure on root-knot nematodes (RKNs) (Meloidogyne spp.) infecting eggplant (Solanum macrocarpon) was studied at two sites in southern Benin naturally infested with these nematodes. After 3 months, soil and root-inhabiting RKN populations were significantly less (P≦0.05) in the plots cropped with vernonia, amaranth, and eggplant amended with poultry manure (PM) at the rate of 40 t ha⁻¹ as compared with the rate of 20 t ha⁻¹ and with the control. Poultry manure was more effective after 2 months than after 3 months. Overall, vernonia was the most effective treatment affecting RKN populations in the roots and the soil. The use of these treatments in nematode management through rotation and co-planted crops is discussed. http://www.phytoparasitica.org posting August 6, 2008.