不同除草剂对间作玉米大豆的药害及除草效果

采用盆栽方法模拟玉米大豆间作模式栽培,选用10种土壤处理除草剂和13种茎叶处理除草剂,研究不同除草剂对玉米、大豆生长发育的影响及杂草的防效。结果表明:通过试验筛选出药害轻或药害后能恢复的5种土壤处理剂和5种茎叶处理剂,5种土壤处理剂分别为二甲戊灵、精异丙甲草胺、扑·乙·滴丁酯、乙·嗪·滴丁酯、嗪酮·乙草胺,5种茎叶处理剂分别为灭草松、噻吩磺隆、双氟·唑嘧胺、氟醚·灭草松、咪唑乙烟酸。二甲戊灵和嗪酮·乙草胺的土壤处理中玉米、大豆的株高、茎粗和干物重与清水对照差异不显著,对玉米、大豆安全,株防效分别为60.58%和60.58%,鲜重防效分别为67.12%和55.35%。精异丙甲草胺影响间作玉米的株高和茎粗,但不影响玉米干物质的积累,株防效和鲜重防效分别为71.96%和78.83%,高于其它除草剂。茎叶处理中灭草松安对玉米、大豆的株高、茎粗和干物重与清水对照差异不显著,株防效为52.7%,低于其它除草剂。噻吩磺隆处理后,玉米、大豆的株高受到抑制,茎增粗,但药害能恢复,且除草效果高于其它处理,株防效和鲜重防效分别为73.88%和96.1%。土壤处理剂二甲戊灵和茎叶处理剂灭草松对玉米、大豆更安全,土壤处理剂精异丙甲草胺和茎叶处理剂噻吩磺隆除草效果更好。     

66%乙·嗪·滴丁酯微乳剂防除春大豆田杂草安全性及药效试验

66%乙·嗪·滴丁酯微乳剂是三元复配混剂,在春大豆田播后苗前进行土壤均匀喷雾,对大豆出苗及生长安全,药后40d对一年生禾本科及阔叶杂草的株防效均大于90%,鲜重防效均大于95%,并且持效期长达45d以上。     

20%烟嘧磺隆·氰草津油悬浮剂的生物活性评价

在温室盆栽条件下,以马唐、反枝苋为试材,采用Gowing法测定了烟嘧磺隆与氰草津复配的联合作用,并对实验室制得的20%烟嘧磺隆.氰草津油悬浮剂进行了大田生物活性评价试验。结果表明,烟嘧磺隆与氰草津复配后对马唐有增效作用,对反枝苋属于相加作用,两者适宜复配,配比为1～4：12.5。于玉米3～5叶期、杂草2～5叶期喷施20%烟嘧磺隆.氰草津油悬浮剂180～300g/hm^2,药后30d的杂草总株防效及鲜重防效分别为83.6%～94.3%、92.7%～99.2%,对玉米安全性较好,玉米株高、产量均大于人工除草处理;在玉米7叶期及杂草5叶期以后施用该药剂,玉米的安全性及杂草株防效均出现下降。     

20%烟嘧磺隆·氰草津油悬浮剂的生物活性评价

在温室盆栽条件下,以马唐、反枝苋为试材,采用Gowing法测定了烟嘧磺隆与氰草津复配的联合作用,并对实验室制得的20%烟嘧磺隆·氰草津油悬浮剂进行了大田生物活性评价试验。结果表明,烟嘧磺隆与氰草津复配后对马唐有增效作用,对反枝苋属于相加作用,两者适宜复配,配比为1～4∶12.5。于玉米3～5叶期、杂草2～5叶期喷施20%烟嘧磺隆·氰草津油悬浮剂180～300 g/hm²,药后30 d的杂草总株防效及鲜重防效分别为83.6%～94.3%、92.7%～99.2%,对玉米安全性较好,玉米株高、产量均大于人工除草处理;在玉米7叶期及杂草5叶期以后施用该药剂,玉米的安全性及杂草株防效均出现下降。     

75%咪唑乙烟酸可溶粉大豆田苗前封闭除草田间药效及安全性试验

田间试验结果表明,75%咪唑乙烟酸可溶粉用药量为5.5~11 g/667 m2,喷液量为30 kg/667 m2,此用药量和喷液量用于大豆田苗前封闭除草,可有效控制大豆田整个生育期杂草。特别对苣荬菜、藜、苋、刺菜有显著防效,对稗草、铁苋菜有理想的防除和控制作用。对大豆安全无药害产生,对大豆后期生长和产量不但无不良影响,而且在株高等方面还有一定的促进作用。     

4种除草剂对夏玉米田杂草及麦苗的防效与安全性比较

选用4种莠去津复配剂进行玉米田杂草防除效果及安全性研究,筛选对夏玉米田杂草及自生麦苗的防效及安全性较好的除草剂。结果表明,31.5%噻酮磺隆·异噁唑草酮+38%莠去津总杂草株防效为88.7%,鲜质量防效为98.48%,防效较好,无明显药害症状,且玉米产量为各药剂处理中最高;22%烟嘧·莠去津和30%苯唑草酮+助剂+38%莠去津对自生麦苗株防效均在80%以上,鲜质量防效在95%以上;30%苯唑草酮+助剂+38%莠去津对莎草的株防效仅45.58%,莎草为主的夏玉米田块尽量不使用。     

几种除草剂在豆科作物田除草效果及安全性测定

为探讨几种化学除草剂对大豆田主要杂草的除草效果及对其他豆科作物安全性,选用除草剂异恶草酮、咪草烟、恶草酮和氯嘧磺隆在4种豆科作物间作田进行播后苗前土壤处理.结果表明:4种除草剂的总杂草株防效和鲜重防效分别为84.2%和84.4%以上,均与对照达到极显著水平,除草效果优良.4种除草剂对藜、马齿苋、反枝苋的株防效最高可达到100%.异恶草酮对反枝苋株防效为45.2%.氯嘧磺隆对稗草的株防效仅为11.7%,但对多年生问剂防效达89.8%,其他3种除草剂对稗草防效均较高,对问剂防效较低.从对豆科作物安全性看,4种除草剂都可以用于大豆田除草,与实际应用情况相符;异恶草酮禁用于绿豆、黄芪和黑豆;恶草酮禁用于黄芪和黑豆;氯嘧磺隆禁用于黄芪;只有咪草烟对4种豆科作物安全.     

大豆苗后除草剂灭草松与精喹禾灵联合防除马唐、反枝苋的研究

在温室内采用单轴等效线法测定大豆苗后除草剂灭草松与精喹禾灵联合作用的结果表明 ,灭草松与精喹禾灵混用对马唐有增效作用 ,随着灭草松的剂量从 0增加到 60 0 ga .i./hm2 ,精喹禾灵抑制马唐 90 %的有效剂量 (ED90 )随之从 14.88ga .i./hm2 下降到 4 .89ga .i./hm2 。当灭草松与精喹禾灵以低剂量混用时 ,对反枝苋表现为拮抗作用 ,而两者以高剂量混用时 ,表现为增效作用     

胡麻苗期阔叶杂草藜高效防除药剂田间筛选

开展了40%2甲·辛酰溴EC等5种除草剂以及40%2甲·辛酰溴EC+48%灭草松AS等9个混用组合防除胡麻田阔叶杂草藜的田间试验,旨在筛选出对胡麻更为安全、对阔叶杂草藜具优良防效的新型除草剂及其混用组合,为安全、有效防除藜提供科学依据。结果表明,30%辛酰溴苯腈EC、40%2甲·辛酰溴EC+48%灭草松AS、30%辛酰溴苯腈EC+48%灭草松AS、40%2甲·辛酰溴EC+30%苯唑草酮SC和30%辛酰溴苯腈EC+30%苯唑草酮SC苗期茎叶喷雾对胡麻安全;对阔叶杂草藜具优良防效,药后45 d的株防效在94.74%~98.24%之间,鲜重防效在96.30%~99.11%之间;对胡麻增产效果显著,产量在2683.35~2830.05 kg/hm~2之间,较未除草对照(CK)增产60.57%~69.35%,较人工除草增产3.92%~9.60%。从安全性、除草效果和产量3方面综合评价,上述5种除草剂(组合)及其混用组合是苗期茎叶喷雾防除胡麻田阔叶杂草藜的安全、高效除草剂,其大面积示范推广的适宜剂量分别为1500 mL/hm~2、750 mL/hm~2+2250 mL/hm~2、750 mL/hm~2+2250 mL/hm~2、750 mL/hm~2+180 mL/hm~2和750 mL/hm~2+180 mL/hm~2。     

玉米与大豆间作条件下不同茎叶处理除草剂的筛选

选用五种除草剂在玉米与大豆间作田间进行茎叶喷施,调查不同处理对田间杂草的防效、作物的安全性和作物产量的影响。结果表明:40 g/L烟嘧磺隆和55%咪唑乙烟酸两种除草剂对杂草防效均在90%以上,而且对玉米和大豆两种作物安全。40 g/L烟嘧磺隆使大豆增产27.8%,,玉米增产16.4%。5%咪唑乙烟酸使大豆增产42%,,玉米增产16.4%。筛选出的这两种除草剂比较适宜于玉米与大豆间作时的茎叶处理除草剂。     

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.     

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.     

Extreme resistance to infection by potato virus X in genotypes of wild tuber-bearingSolanum species

Summary Clones derived from thirty-one different accessions (nineteen of Argentine origin) belonging to eightSolanum species were screened for resistance to infection by potato virus X strain cp (PVX cp) by mechanical inoculation of plantlets that had been micropropagated in vitro. Estimates of PVX multiplication obtained by enzyme linked immunosorbent assay and slot blot nucleic acid hybridization allowed the identification of resistant clones derived from five accessions belonging toS. commersonii S. oplocense, S. sparsipilum andS. tuberosum andigena. Resistant genotypes supported PVX concentrations 5 to 15 times smaller than did the susceptible control cultivar Spunta. Graft inoculation test confirmed the presence of extreme resistance similar to that conferred by the ‘immunity’ gene X¹ (also called RX_act).     

Marine Pharmacology in 2009–2011: Marine Compounds with Antibacterial,Antidiabetic, Antifungal,Anti-Inflammatory,Antiprotozoal, Antituberculosis,and Antiviral Activities; Affecting the Immune and Nervous Systems,and other Miscellaneous Mechanisms of Action ?

The peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories.     

Recent Modifications of Chitosan for Adsorption Applications: A Critical and Systematic Review

Chitosan is considered to be one of the most promising and applicable materials in adsorption applications. The existence of amino and hydroxyl groups in its molecules contributes to many possible adsorption interactions between chitosan and pollutants (dyes, metals, ions, phenols, pharmaceuticals/drugs, pesticides, herbicides, etc.). These functional groups can help in establishing positions for modification. Based on the learning from previously published works in literature, researchers have achieved a modification of chitosan with a number of different functional groups. This work summarizes the published works of the last three years (2012–2014) regarding the modification reactions of chitosans (grafting, cross-linking, etc.) and their application to adsorption of different environmental pollutants (in liquid-phase).     

Pharmacokinetics of Marine-Derived Drugs

Marine organisms represent an excellent source of innovative compounds that have the potential for the development of new drugs. The pharmacokinetics of marine drugs has attracted increasing interest in recent decades due to its effective and potential contribution to the selection of rational dosage recommendations and the optimal use of the therapeutic arsenal. In general, pharmacokinetics studies how drugs change after administration via the processes of absorption, distribution, metabolism, and excretion (ADME). This review provides a summary of the pharmacokinetics studies of marine-derived active compounds, with a particular focus on their ADME. The pharmacokinetics of compounds derived from algae, crustaceans, sea cucumber, fungus, sea urchins, sponges, mollusks, tunicate, and bryozoan is discussed, and the pharmacokinetics data in human experiments are analyzed. In-depth characterization using pharmacokinetics is useful for obtaining information for understanding the molecular basis of pharmacological activity, for correct doses and treatment schemes selection, and for more effective drug application. Thus, an increase in pharmacokinetic research on marine-derived compounds is expected in the near future.