不同药剂对马铃薯晚疫病的防治效果试验

为比较多种马铃薯晚疫病常用防治药剂在不同浓度下对晚疫病的防治效果,选择了4种常用药剂采用随机区组设计,进行不同浓度下的防治对比试验。结果表明:687.5 g/L银法利悬浮剂和75%代森锰锌水分散粒剂效果较好,综合农药用量和防治用工等防治成本考虑,在生产中,采用687.5银法利悬浮剂开展防治,以125 mL/667 m2施2次和75 mL/667 m2施3次最为适宜,采用75%代森锰锌水分散粒剂开展防治,以100 g/667 m2施3次和200 g/667 m2施2次最为适宜。     

马铃薯晚疫病优化防治决策

依据比利时马铃薯晚疫病预警系统模型预测,确定马铃薯主要生育期内,病菌生成潜在侵染次数、代数和最佳防治期及防治次数,运用多目标决策方法,通过对西吉县‘青薯9号’品种马铃薯晚疫病田间药剂防治试验进行决策分析,获得了防治成本低(46.5~49.5元/667m2)、防治效果高(病指防效82.39%~85.78%)和保产效果好(41.40%~45.49%)的综合效益决策矩阵及决策靶,为指导马铃薯晚疫病田间防治提供了科学依据。     

不同药剂组合对马铃薯晚疫病的防治效果分析

马铃薯晚疫病是马铃薯生产中的主要病害之一,在定西市马铃薯种植区发生普遍、危害重,生产中利用杀菌剂防治仍是重要的措施。试验采用随机区组法研究了不同药剂组合对马铃薯晚疫病防效和产量的影响。结果表明,72%霜脲·锰锌1 950 g/hm~2+23.4%双炔酰菌胺450 m L/hm~2+250 g/L醚菌酯280 m L/hm~2+687.5 g/L氟菌·霜霉威980 m L/hm~2和80%代森锌1 350 g/hm~2+25.75%多抗·福美双1 900 g/hm~2+28%霜脲·霜霉威2 500 g/hm~2+52.5%噁酮·霜脲氰570 g/hm~2组合具有显著的防治效果。     

不同药剂防治小麦白粉病田间药效试验

为筛选防治小麦白粉病的高效新药剂,对5种杀菌剂进行了田间防效试验。结果表明,药后10 d,30%醚菌酯WP 30 g/667 m2、20 g/667 m2防效分别为78.57%和72.10%,防治效果优于其它药剂处理的防效;20%三唑酮EC 80 ml/667 m2和80%戊唑醇WP 15 g/667 m2处理对小麦白粉病的防效分别为62.63%、54.40%;30%氟菌唑WP 20 g/667 m2和20%乙嘧酚磺酸酯ME 20 ml/667 m2处理对小麦白粉病防治效果分别为50.17%和44.99%。药后20 d,30%醚菌酯WP 30 g/667 m2和30%醚菌酯WP 20 g/667 m2处理对小麦白粉病的防效分别达到93.40%和83.53%,防效在各处理中最高,其次为20%三唑酮EC 80 ml/667 m2,防效为61.25%,以上3处理之间差异不显著;但与对照及其他处理都达到显著性差异;80%戊唑醇WP 15 g/667 m2和20%乙嘧酚磺酸酯ME 20 ml/667 m2的防治效果分别为42.60%和18.28%,30%氟菌唑WP 20 g/667 m2处理对小麦白粉病防治效果仅有5.90%。因此30%醚菌酯WP 30 g/667 m2和20 g/667 m2处理可有效控制小麦白粉病的发生及危害,且对小麦生长安全,可以作为三唑酮的替代药剂或与其他药剂合理轮换使用。     

不同药剂对水稻病害防治效果试验简报

利用对比的方法研究不同药剂对水稻病害的防治效果,结果表明,各试验药剂均对水稻安全,无药害发生。并且试验中30%爱苗乳油用量为20 g/667 m2时对水稻纹枯病防治效果最佳,防效为79.6%;1%申嗪霉素用量150 g/667 m2时对水稻褐变穗防效最好,防效为74.5%。但试验数据为1 a试验结果,还有待进一步验证。     

250g/L嘧菌酯悬浮剂对不同地区马铃薯晚疫病的防治效果分析

杀菌剂防治马铃薯晚疫病是生产中采用的主要措施。通过施用250 g/L嘧菌酯悬浮剂对河北、甘肃、青海3个地区马铃薯晚疫病的防治效果进行分析。结果表明,250 g/L嘧菌酯悬浮剂对3个地区马铃薯晚疫病均具有较好的防治效果;在河北地区,250 g/L嘧菌酯悬浮剂的有效成分用量为75.00 g/hm2时,对马铃薯晚疫病的防效达到77.53%;在青海地区,各试验处理的防效达到71.26%~84.02%;在甘肃地区防治效果更好,防效均达到80%以上。该试验结果为250 g/L嘧菌酯悬浮剂在生产上的推广使用提供理论依据。     

不同农药对水稻制种田稻飞虱的防效试验

为筛选出高效、低毒、低残留的农药防治稻飞虱,设置了10%醚菊酯悬浮剂等4种不同药剂对第五代稻飞虱的防治效果试验,结果表明:10%醚菊酯悬浮剂100 ml/667m2、25%噻嗪酮可湿性粉剂50 g/667m2+80%敌敌畏乳油畏100 ml/667m2、25%吡蚜酮可湿性粉剂25 g/667m2对水稻稻飞虱均有较好的防效,可在生产上推广应用,建议不同药剂间轮换使用。     

不同药剂及施用方式对马铃薯疮痂病的防效

马铃薯疮痂病被视为马铃薯生产中的第四大病害,严重影响马铃薯的外观、等级和品质。为求得防效好的马铃薯疮痂病防治方法,试验采用种薯处理与土壤处理相结合的方法进行田间比较试验。试验品种为‘尤金’,供试微生物制剂有5种,化学药剂1种。对照为常规处理,即不采取任何拌种与沟施。结果表明,防治效果以处理5最好,达到55.17%,处理5是在常规药剂(滑石粉+甲托+链霉素)拌种下,微生物肥料2(薯益生)沟施;其次为处理6防治效果达50.08%,处理6是在常规药剂拌种下,化学药剂爱可(化学药剂1)沟施。处理5、6的发病率及病情指数均显著低于对照。处理5的产量为1 767 kg/667m2,处理6的产量为1 740 kg/667m2,但与对照产量(1 646 kg/667m2)差异不显著。     

不同药剂组合对马铃薯晚疫病的防治效果

马铃薯晚疫病是马铃薯生产中的重要病害,是影响马铃薯产量和品质的重要因素之一,在云南春作马铃薯上普遍发生,且危害较重,给当地马铃薯产业带来了巨大的经济损失。为减轻马铃薯晚疫病对马铃薯生产造成的损失,试验研究了11种药剂7种药剂组合(包衣剂+保护剂+治疗剂)通过播种期种薯包衣,现蕾期叶面喷施一次保护剂,发病初期和发病中期叶面各喷一次治疗剂的方法防治马铃薯晚疫病。结果表明,药剂组合种薯包衣+甲霜·锰锌+氟吡菌胺·霜霉威的防治效果最好,防治效果达到60.99%,增产率176.28%,增效率152.27%;其次是种薯包衣+霜脲·锰锌+氟吡菌胺·霜霉威组合,防治效果达到60.15%,增产率173.20%,增效率150.55%。这2个药剂组合对马铃薯晚疫病均有极显著的防治效果,增产增效明显。     

不同杀菌剂防治马铃薯晚疫病田间药效试验

试验研究了7种杀菌剂对马铃薯晚疫病的防治作用。结果表明:68.75%银法利悬浮剂1125 g/hm2、53%金雷多米尔水分散颗粒剂1500g/hm2、60%氟吗啉.代森锰锌可湿性粉剂1225g/hm2、72%克露可湿性粉剂2000g/hm2对马铃薯晚疫病防效分别为88.38%、86.15%、84.55%、81.68%,是防治马铃薯晚疫病较理想的药剂,且增产效果明显,建议在生产上交替使用。     

Mineral composition of some traditional Mexican teas

Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots ofTagetes lucida, T. filifolia, Elytraria imbricata, andHolodiscus dumosus, and from root xylem ofCeanothus depressus andPhaseolus ritensis. Native uses of these teas are also described.     

Studies on natural repellents against potato tuber moth (Phthorimaea operculella Zeller) in country stores

Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong (1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage, sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over 45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield of a subsequent crop.     

Comparative Assessment of the Efficacy of Various Nitrogen Fertilizers

Summary

The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices.     

Redox Status and Neuro Inflammation Indexes in Cerebellum and Motor Cortex of Wistar Rats Supplemented with Natural Sources of Omega-3 Fatty Acids and Astaxanthin: Fish Oil,Krill Oil,and Algal Biomass

Health authorities worldwide have consistently recommended the regular consumption of marine fishes and seafood to preserve memory, sustain cognitive functions, and prevent neurodegenerative processes in humans. Shrimp, crabs, lobster, and salmon are of particular interest in the human diet due to their substantial provision of omega-3 fatty acids (n-3/PUFAs) and the antioxidant carotenoid astaxanthin (ASTA). However, the optimal ratio between these nutraceuticals in natural sources is apparently the key factor for maximum protection against most neuro-motor disorders. Therefore, we aimed here to investigate the effects of a long-term supplementation with (n-3)/PUFAs-rich fish oil, ASTA-rich algal biomass, the combination of them, or krill oil (a natural combination of both nutrients) on baseline redox balance and neuro-inflammation indexes in cerebellum and motor cortex of Wistar rats. Significant changes in redox metabolism were only observed upon ASTA supplementation, which reinforce its antioxidant properties with a putative mitochondrial-centered action in rat brain. Krill oil imposed mild astrocyte activation in motor cortex of Wistar rats, although no redox or inflammatory index was concomitantly altered. In summary, there is no experimental evidence that krill oil, fish oil, oralgal biomass (minor variation), drastically change the baseline oxidative conditions or the neuro-inflammatory scenario in neuromotor-associated rat brain regions.     

Potential of dry fractionation of wheat bran for the development of food ingredients,part II: Electrostatic separation of particles

Wheat bran is a composite material made of several layers, such as pericarp, testa and aleurone. It could be fractionated into purified fractions, which might either be used as food ingredients, or serve as a starting material for extraction of bioactive compounds. The aim of this work was to evaluate the potential of using electrostatic separation as a way to obtain purified fractions from wheat bran. Ultrafine-ground bran obtained either by cryogenic grinding or by grinding at ambient temperature was used as starting material. The ultrafine bran was then charged by tribo-electrification and introduced in a chamber containing two high voltage electrodes, where bran particles were separated depending on their acquired charge, allowing positively and negatively charged fractions to be collected separately. The particle size distribution, microstructure and biochemical composition of the obtained fractions were studied. The charge of the particles was influenced by their biochemical composition: particles rich in highly branched and cross-linked arabinoxylans (pericarp) were separated from particles rich in β-glucan, ferulic acid and para-coumaric acid (aleurone cell walls). The testa and the intracellular compounds from aleurone were not highly charged, neither positively nor negatively. The most positively charged fraction represented 34% of the initial bran, and contained 62% of the ferulic acid present in the initial bran. The yield of the separation process was good (5.4% loss), and could be further increased.     

In vitro antimicrobial activity of different accessions ofSolanum commersonii Dun. from Uruguay

Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds.     

Novel food and non-food uses for sorghum and millets

Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.     

<Emphasis Type="Italic">Pulque</Emphasis>, An Alcoholic Drink from Rural Mexico,Contains Phytase. Its <Emphasis Type="Italic">in vitro</Emphasis> Effects on Corn Tortilla

Pulque is made by fermenting the agave sap or aguamiel of Agave atrovirens with a whole array of microorganisms present in the environment including several lactic acid bacteria and yeasts such as Saccharomyces cerevisiae. Ascorbic acid was determined in pulque and aguamiel, respectively. Phytase activity in lees, liquid and freeze-dried pulque was assayed by measuring the appearance of phosphate from phytate by a colorimetric method likewise phosphate from phytate present in fresh corn tortilla was measured after in vitro incubation with pulque. Iron, zinc, calcium, magnesium and selenium contents were measured in pulque and corn tortilla as well as in nixtamalized corn flour (NCF), the latter is used to make instant tortilla, since corn provides most of the energy as well as most of the phytate in the Mexican rural diet. Pulque showed phytase activity but much less ascorbic acid and iron than previously reported; additionally, phytase in pulque hydrolyzed most of phytate’s corn tortilla. Lees, which is mostly made of pulque’s microbiota, significantly accumulated iron and zinc but no selenium. NCF was fortified with iron by the manufacturers but poorly blended. There were significant differences on selenium content between tortillas samples, apparently some soils in central Mexico are selenium deficient. Moderate pulque intake appears to increase the bioavailability of iron and zinc bound by phytate in corn.