Nitrogen-enhanced phytotoxicity to cucumber of low concentrations of EPTC and metolachlor

The impact of nitrogen source on the response of cucumber (Cucumis sativus) seedlings to sub-toxic concentrations (<10⁻⁶ ) of metolachlor and EPTC was studied in nutrient solutions. Nitrogen increased the phytotoxicity of low concentrations of both herbicides. The presence of a relatively high ammonium level (5m ) in solution enhanced growth inhibition (up to 50%), increased total nitrogen (20%) and protein content (26%), and resulted in less K⁺ (50%) and Ca²⁺ (70%) absorption. Under optimal nitrogen nutrition conditions, metolachlor temporarily inhibited plant growth, and both herbicides decreased the protein content in cucumber leaves. The effect of herbicides at the high ammonium level on plant growth was stronger and more long-lasting compared with control growing conditions.     

2006年欧洲人畜共患病的感染情况报告

2006年欧洲人畜共患病的感染情况年度总结报告,由欧盟食品安全局(EFSA)和欧洲疾病预防和控制中心(ECDC)于近期公布.该报告阐述了人畜共患病传染、媒介、抗生素抗性和食源性疾病在25个欧盟成员国和5个非成员国(保加利亚、冰岛、列支敦士登、挪威和罗马尼亚)暴发的最新趋势和发生数字.以下是该报告的背景和结果.     

Flock-level case-control study of slaughter-lamb pneumonia in New Zealand

Subclinical pneumonia is common in production lambs, and causes reductions in growth rate. We selected farms from meat-inspection records of three New Zealand abattoirs from December 2000 to May 2001 to study risk factors for flocks having ≥3% of their lambs with ≥10% of the lung surface with lesions, compared to flocks with a zero lamb-level prevalence of such pneumonia. A questionnaire of management practices was mailed to participating managers of case and control farms and we received responses from 132/192 (69%) cases and 181/300 (60%) in control farms. Risk factors for case farms were shearing lambs on the day of weaning (OR 6.4), breeding ewe replacements on-farm (OR 4.0), and the percentage of lambs sold between March and May (OR 1.0 for <23% sold (reference category), OR 3.9 for 23–42% sold, OR 2.7 for 43–64% sold, OR 4.3 for >64% sold). Protective factors included: grazing lambs at a fixed stocking rate after weaning (OR 0.4), injecting lambs with vitamin B12 at the time of docking (OR 0.4), and at the time of weaning (OR 0.3). Path analysis was used to show important associations between risk and protective factors differentiated according to time (e.g. before and after birth, at weaning and during growth on pasture). Flocks breeding their own ewe replacements were more likely to shear lambs at weaning, were less likely to buy lambs post-weaning and more likely to have ill-thrift present in >5% of lambs post-weaning. The purchase of lambs post-weaning was indirectly associated with greater odds of pneumonia at slaughter.     

Effects of increasing days of exposure to prepartum transition diets on reproduction and health in dairy cows

Objective To evaluate the effect of the number of days exposure to a prepartum transition diet on reproduction and health in dairy cows. Design A prospective cohort study. Procedures We enrolled 1008 dairy cows from three herds to examine the effects on reproduction and health of increased days exposure to prepartum transition diets that included ryegrass pasture, ryegrass silage, cereal hay, grain, by-products, oilseed meals, BioChlor®, rumen modifiers, minerals and vitamins. Diets provided 9.9 MJ metabolisable energy per kg dry matter (DM), a metabolisable protein balance of 286 g/day and a dietary cation anion difference of −150 meq/kg DM. Statistical models controlled for herd, calving day, age and gestation period. Results In two of the three herds increased days exposure to prepartum transition diets increased the hazards of submission for breeding, conception and clinical mastitis, and decreased the hazard of cow removal. The odds of pregnancy by 6 and 21 weeks after the mating start date tended to increase with increasing days of exposure to prepartum transition diets. Conclusions Increasing exposure to a prepartum transition diet improved the calving to conception interval, tended to improve the odds of pregnancy and reduced the risk of culling of cattle, but increased the hazard of clinical mastitis.     

Ozonated water electrolytically generated by diamond-coated electrodes controlled phytonematodes in replanted soil

Journal of Plant Diseases and Protection - Phytonematodes cause severe yield losses in horticulture, partly because they are difficult to manage. Compact, energy-efficient generators that...     

Growth,Development and Yield of Crambe Abyssinica Under Saline Irrigation in the Greenhouse

Salinity is one of the major factors limiting agricultural productivity in arid and semi‐arid regions. Saline areas around the world are increasing and sources of fresh water are decreasing. The increasing importance of the use of brackish water to supplement regular irrigation has demonstrated a need for finding new potential plants with tolerance to irrigation with saline water which can be used in industrial agriculture. The aim of this study was to determine whether irrigation with brackish water of Crambe Abyssinica, a plant commonly used for industrial oil production and for ornamental purposes and with high economical value, especially in Central Asia and the Aral Sea region, is feasible. One more goal was to study how it influences growth and development, seed and oil yield and some physiological parameters such as photosynthesis, transpiration, chlorophyll content, osmotic potential and accumulation of fresh and dry weight. The effects of three salinity levels, 3, 6 and 9 dS m^?1, were investigated in a greenhouse experiment during two consecutive years. Results of this study showed that growth of Crambe abyssinica in arid zones and irrigation with mild saline water up to EC 6 dS m^?1, mostly common in these areas is feasible, suggesting tolerance to moderate salinity levels and feasibility of its culture in areas of the Aral Sea with adequate salinity levels. Consequently, in spite of the fact that biomass and seed yield were significantly decreased in plants irrigated with brackish water, Crambe abyssinica might be cultivated as an alternate source of green biomass and for industrial vegetable oil under conditions not suitable for conventional plant production.