Comparative performance of the highly invasive Mimosa invisa and its less invasive subspecies under different nutrient and light conditions

Invasive plants may be more plastic than non‐invasive plants and maintain high fitness under various environmental conditions. Previous studies mainly focused on the comparisons between invasive and native plants, and comparisons between highly invasive and less invasive exotic species are still relatively rare, especially for comparisons at the subspecies level. This study examined the effects of nutrient addition and shading on the performance of the highly invasive Mimosa invisa and its less invasive subspecies M. invisa var. inermis under either isolated or competitive conditions. Nutrient addition increased biomass and plant height and decreased root‐to‐shoot ratio (R/S). Shading decreased biomass and R/S and increased plant height. Under isolated conditions, the two invaders did not differ in R/S, plant height and plasticity of these traits in response to nutrient addition or shading, and the two invaders also did not differ in biomass production under each of the nutrient and light treatments. When the two invaders competed with each other, M. invisa outcompeted M. invisa var. inermis under high soil nutrient conditions, and the two invaders did not differ in performance under other growth conditions. Thus, only considering competition may we find out the difference between highly invasive species and their closely related, less invasive subspecies. Management of M. invisa should focus on habitats with high soil nutrient availability, in which M. invisa is more likely to dominate.     

2018年我国农药进出口特点与2019年趋势分析

Li Lin;Jin Hejiang;Huang Xinhe;Cao Bingwei;Wu Lihui;Liu Pingping;Qu Mengmeng;Wu Houbin(The Institute for the Control of Agrochemicals,Ministry of Agriculture and Rural Affairs,Beijing 100125,China)     

CRISPR/Cas systems:The link between functional genes and genetic improvement

With the ever-increasing human population and deteriorating environmental conditions, there is an urgent need to breed environmentally friendly and resource-con...     

68.75%噁酮.锰锌水分散粒剂对柑橘黑点病的防治效果

柑橘黑点病(Diaporthe citri)是危害柑橘最严重的病害之一,每年需要喷施4-5次杀菌剂进行防治,为明确68.75%噁酮.锰锌WG对柑橘果实黑点病的防治效果,分别在浙江黄岩和常山进行了田间试验。结果发现黄岩试验点68.75%噁酮.锰锌WG 500倍全程5次对黑点病的防治效果为84.79%、常山试验点同样药剂800倍全程4次对黑点病的防治效果为74.10%,效果不亚于常规推荐的杀菌剂代森锰锌,说明68.75%噁酮.锰锌WG 500-800倍在柑橘花谢2/3后开始第一次用药,隔20-25天喷施一次,共用药4-5次,可有效防治柑橘黑点病。     

The Effects of Freshwater Clam (Corbicula fluminea) Extract on Serum Tumor Necrosis Factor-Alpha (TNF-α) in Prediabetic Patients in Taiwan

Freshwater clam extract (FCE) is a functional food that regulates the immune system and has been demonstrated in numerous studies to display desirable anti–tumor necrosis factor-alpha (TNF-α) responses. In addition, excess TNF-α production is positively associated with type 2 diabetes. However, few longitudinal clinical studies evaluating the efficiency and toxicity of FCE are available. This article reports that patients with prediabetes who received FCE had a desirable outcome of a reduction in serum TNF-α for a long period. This was a double-blind, randomized, parallel clinical trial conducted using FCE intervention and placebo groups, and 36 patients with prediabetes were enrolled. Two grams of FCE or placebo was consumed daily for 180 consecutive days. The serum of the participants was collected at four time points (0M: before the intervention; 3M: after 3 months of intervention; 6M: after 6 months of intervention; 12M: 6 months after cessation of intervention at 6M). A serum TNF-α concentration higher than 4.05 pg/mL was defined as a cut-off value. FCE reduced serum TNF-α in all participants at 6M and 12M. Moreover, FCE significantly suppressed serum TNF-α concentrations at 6M and 12M and inhibited TNF-α release with time series in subjects with elevated TNF-α values. FCE intervention effectively reduced serum TNF-α and persistently sustained the effects for half a year in patients with prediabetes. Gas chromatography–mass spectrometry (GS-MS) analysis revealed that the major components of FCE were phytosterols and fatty acids, which exerted anti-inflammatory and anti-TNF-α abilities. Hence, FCE has the potential to be developed as a natural treatment for prediabetic patients in Taiwan.     

Development of a Sequential Decision-Making Model for Controlling Multiple Air Pollutants Under Stochastic Uncertainty

Most of previous programming methods for air-quality management merely considered single pollutant from point sources. However, air pollution control is characterized by multiple pollutants from various sources. Meanwhile, uncertain information in the decision-making process cannot be neglected in the real-world cases. Thus, an inexact multistage stochastic programming model with joint chance constraints based on the air quality index (air-quality management model with joint chance constraints (AQM-JCC)) is developed for controlling multiple pollutants deriving from point and mobile sources and applied to a regional air-quality management system. In the model, integrated air quality associated with the joint probability existing in terms of environmental constraints is evaluated; uncertainties expressed as probability distributions and interval values are addressed; risks of violating the overall air-quality target under joint chance constraints are examined; and dynamics of system uncertainties and decision processes under a complete set of scenarios within a multistage context are reflected. The results indicate that useful solutions for air quality management practices in sequential stochastic decision environments have been generated, which can help decision makers to identify cost-effective control strategies for overall air quality improvement under uncertainties.     

中国甘蔗气候类型和特点的客观分析

依据作物生态学原理选定评价指标,应用系统聚类法进行全国甘蔗气候分类。划分的9类甘蔗气候区都呈现明显的区域性分布,其气候特点既反映光、温、水时段分配匹配的差异,也反映气候要素总量差异,基于同一标准分析了各类甘蔗气候的利弊影响。提高了对于我国甘蔗气候的整体性客观认识,对甘蔗生产管理有重要指导意义。     

基于虚拟现实的清铃机设计与仿真

采棉机是提高棉花采摘环节机械化水平的重要的工具,其关键部件清铃机的设计对机采棉清理加工技术的改善有着重要意义.虚拟现实技术的出现为解决传统产品开发过程中存在的问题提供了有效的途径.为此,以清铃机作为研究对象,使用Pro/E进行清铃机虚拟样机设计,运用ADAMS对关键部件进行动力学仿真,并在VAPlatform平台上进行虚拟装配,最后在nVision平台中进行产品展示,成功地在虚拟环境中实现了产品开发设计全过程.该研究旨在为虚拟现实技术在农业机械上的应用提供参照.     

发展广西秸杆畜牧业的思路和对策

广西有丰富的秸秆资源,发展千秆畜牧业的潜力巨大,千杆畜牧业是一项可持续发展的农业生产事业。秸杆的氨化技术可以有效地提高秸杆的营养价值,发展秸杆养畜,需要有优于牲畜品种,才能提高经济效益,所以,广西发展秸杆畜牧业,需要政府重视,政策跟进,大力推广秸杆氮化技术,加快引进热带型的优良黄牛品种改良广西黄牛品种的步伐。