茎叶涂抹灌根法测试生物除草剂70014吸收与传导试验初报

采用茎叶涂抹灌根法对生物除草剂70014进行了吸收和传导试验。从灌根法可以看出,70014能通过黄瓜根系的吸收与传导引起整株植株的死亡;从茎叶涂抹法来看,70014在茎叶上主要表现为触杀活性,但从真叶和下胚轴涂药来看,还有一定的吸收和传导性。     

杨凌霉素除草活性初步研究

[目的]研究杨凌霉素对小麦、水稻、稗草和反枝苋的除草活性。[方法]培养皿内处理2 d或3 d后测定种子萌发数和幼根长度;盆栽处理15 d后测定幼苗鲜质量;AFLP处理小麦幼根基因组DNA后统计图谱条带。[结果]杨凌霉素对种子萌发和幼根生长均有抑制作用,其中对稗草种子萌发和小麦幼根生长的抑制效果最强,EC50值分别为26.20、20.90 mg/L;但对幼苗生长的防效均低于30%;基因组DNA多态性显著提高,且与药剂浓度存在明显的剂量关系。[结论]杨凌霉素具有一定的除草活性。     

紫丁香不同器官的除草活性

为了明确紫丁香不同器官的除草活性,为进一步开展活性化合物的研究提供依据,以生菜、黄瓜、反枝苋、茼麻、小麦和稗草为受体植物,采用琼脂混粉法进行了室内除草活性的测定.结果表明:紫丁香的不同器官粉末在10 g/L添加质量浓度下对各受体植物幼苗的生长均具有不同程度的抑制作用,且普遍对胚根(或种子根)生长的抑制效果高于对胚轴(或胚芽鞘)生长的抑制.其中以叶和花器官表现出的抑制活性最强,而根和茎的效果则相对较低,说明紫丁香的叶和花中均含有较高除草活性物质.     

黄腐酸对稗草幼苗及其生长素类物质合成相关基因的影响

[目的]探究黄腐酸对稗草幼苗及其生长素类物质合成相关基因的影响。[方法]模拟稻田淹水条件并加入不同浓度黄腐酸溶液处理稗草幼苗,7 d后测定稗草株高、根长和鲜重,实时荧光定量PCR技术对候选基因表达量进行检测。[结果]质量浓度为0.02 g/L黄腐酸处理后,稗草株高、根长与对照组相比,分别提高了25.49%、8.04%;根长提高不显著。随着浓度的提升,黄腐酸显现出对稗草幼苗的抑制作用、并逐渐增强,质量浓度在0.8 g/L时,对株高、根长、鲜重抑制率分别为32.30%、92.82%、42.54%,后期出现黄化死亡现象。质量浓度为0.02 g/L黄腐酸诱导稗草生长素合成基因EC_v6.g043558和EC_v6.g104724表达量显著上调;质量浓度为0.8 g/L黄腐酸处理后,TDC相关基因EC_v6.g033915、ALDHs功能相关基因EC_v6.g089449和EC_v6.g007956表达量均显著降低。[结论]不同浓度黄腐酸通过影响生长素类物质合成相关基因促进或抑制稗草的生长。     

芬顿氧化法深度处理亚麻生产废水

亚麻生产要进行煮炼脱胶处理,过程中产生的大量胶质,常规的生物处理不能有效去除.往往需要后续氧化处理.试验采用芬顿氧化法处理生物处理后的亚麻废水.该废水COD的质量浓度为1747 mg/L,色度为200倍,通过正交试验和单因素影响试验获得最佳控制条件为pH值为4.5.FeSO4投加量1 500mg/L,H2O2投加量1500mg/L,反应时间为1 h,在最佳条件下,COD去除率为57%,色度去除率达到90%以上.     

新化合物JS412除草活性的生物测定

JS412是经过初筛具有较高除草活性的新化合物.本文采用黄瓜幼苗形态法、稗草中胚轴法、玉米根长法、小麦去胚乳法及浮萍法测试了JS412的生物活性.结果表明浮萍法比较适合于新化合物JS412的室内生物测定,浮萍法测定JS412的萍体抑制中浓度为0．6002mg／L.     

生物接触氧化工艺处理高含盐废水的研究

采用生物接触氧化法处理高含酸盐废水,考察盐浓度连续升高时对COD去除率的影响及抗冲击能力。结果表明,进水硫代硫酸钠的浓度在573~14 812 mg/L时,出水COD浓度小于500 mg/L,COD去除率91%~95%;当生物接触氧化系统受到冲击时,恢复较快,一般3~5个周期后即可恢复正常。     

6%嘧肽菌净水剂防治黄瓜白粉病药效试验

室内盆栽试验结果表明,6％嘧肽菌净水剂防治黄瓜白粉病效果优异,兼有保护和治疗作用。质量浓度在60mg/L以上时,其防效均高于常用药剂三唑酮（150mg／L）,苗期施用150mg/L的药液,防效可达80％以上。初步研究表明该药剂具有内吸传导性能,既可向上传导也可向下传导,以向下传导为主。保护地防效试验中6％嘧肽菌净水剂质量浓度为75mg/L对黄瓜白粉病的相对防效达83．85％,显著优于对照药剂15％三唑酮粉剂300mg／L,并且对黄瓜安全。     

5种植物病原真菌粗毒素防除草坪杂草的筛选

通过对5种植物病原真菌产生的毒素进行粗提,并用其对稗草、反枝苋、蒲公英、苘麻4种供试草坪杂草进行种子萌发抑制试验,对其除草活性进行研究。结果表明,烟草赤星病菌和玉米小斑病菌的粗毒素对草坪杂草种子的萌发有很强的抑制作用,而且对它们的芽和根的生长抑制也很强。安全性试验表明,烟草赤星病菌的粗毒素对供试草坪草种子的萌发、芽和根的生长安全。     

高浓度山梨酸废水生化处理

针对高浓度山梨酸废水具有有机物浓度高、难降解的特点 ,从优化厌氧生化处理入手 ,设计了厌氧—生物接触氧化法的工艺路线进行实验研究。结果表明 ,经 5d厌氧处理后 ,BOD/COD值由 0 .17提高到 0 .2 8,再配合12h生物接触氧化处理 ,使COD从 7.0 0× 10 3mg/L左右降至 1.5 8× 10 3mg/L ,COD平均总去除率达 77.4%。并对生物接触氧化段填料进行了优选与研究     

2E-2-甲基-3-苯基丙烯酰氧基烃基膦酸二乙酯的合成与生物活性研究

设计、合成了系列新的2E-2-甲基-3-苯基丙烯酰氧基烃基膦酸酯衍生物,经元素分析、IR、1HNMR、31PNMR和MS测试而确定它们的结构,初步的生物活性测试结果表明,部分标题化合物对小麦、萝卜、黄瓜和稗草的根或茎具有良好的抑制活性。     

Identification of Phytotoxic Substances from Early Growth of Barnyard Grass (Echinochloa crusgalli) Root Exudates

Barnyard grass is a problematic weed worldwide. It competes with crops and causes reduction in crop yields. In this study, barnyard grass suppressed rice emergence, and the degree of rice inhibition was proportional to the density of barnyard grass. Root exudates of barnyard grass reduced germination and growth of lettuce, rice, and monochoria. Fifteen compounds potentially involved in the phytotoxic activities of barnyard grass were isolated and identified, including phenolics, long-chain fatty acids, lactones, diethyl phthalate, acenaphthene, and derivatives of phthalic acids, benzoic acid, and decane. Quantities of diethyl phthalate, decanoic acid, myristic acid, stearic acid, 7,8-dihydro-5,6-dehydrokavain, and 7,8-dihydrokavain were 2.7, 11.1, 19.6, 35.5, 10.3, and 15.5 μg/ml of barnyard grass root exudates, respectively. The two lactones exhibited the greatest inhibition, followed by the phenolics and the derivatives of phthalic acids. Fatty acids had stronger suppression than diethyl phthalate and ethyl ester-4-ethoxy-benzoic acid. The acenaphthene and decane derivatives were the least phytotoxic. The phytotoxins released by barnyard grass roots showed strong inhibition on growth of broadleaf indicator plants and paddy weeds, but were less effective on barnyard grass itself and rice. Our study revealed that in addition to competition, barnyard grass also interferes with rice and other plants in its surroundings by chemical means.T. D. Khanh and I. M. Chung are members of the research team of Friendly Environmental Low Input Natural Herbicide New Material Study of the Konkuk University.     

Allelopathic polyacetylenes fromCentaurea repens (Russian knapweed)

The allelopathic weed Russian knapweed (Centaurea repens) was found to contain polyacetylenes VIII–XIV in the roots. Dose vs. response of the root length elongation against lettuce, alfalfa, barnyard grass, and red millet showed IX to be active. Closely related isomers were not active. Examination of the soil surrounding the Russian knapweed roots revealed the presence of IX in sufficient concentration to have an appreciable effect on the surrounding plant community.     

1,3,2-二氮磷杂环戊烷-4-酮类化合物的除草活性

运用油菜根伸长法和小杯法测定了1,3,2-二氮磷杂环戊烷-4-酮类化合物的除草活性,结果表明化合物Ⅰ对油菜和稗草的根茎抑制效果好,化合物Ⅱ对油菜根生长有一定促进作用。     

土壤含沙量和含水量对JS913除草活性和作物安全性的影响

采用浇灌法分别测定了不同土壤含沙量和含水量条件下JS913对稗草的除草活性和对玉米的安全性。结果表明在试验的4种土壤含沙量中,随着土壤含沙量的增加,JS913对稗草活性增加,对玉米的药害增大;含水量为18%时,JS913除草活性不能表现,含水量在25%~40%的范围内,随着含水量的增加JS913对稗草活性增加,对玉米的药害也增大。     

18%二甲戊灵·异恶草松可湿性粉剂防除移栽稻田杂草药效试验研究

采用田间小区试验方法,研究了18%二甲戊灵·异恶草松可湿性粉剂防除稻田杂草药效试验。结果表明在水稻移栽5～7d,缓苗后施用剂量为有效成份0.1755～0.351kg/hm2,对稗草的防效幅度为95.8%～100%,对各种阔叶杂草的防效幅度为80.0%～100%,对莎草科杂草的防效幅度为86.7%～100%,对各种杂草的鲜重抑制效果为93.6%～99.9%。杀草谱广,持效期长,而且对水稻生长发育无不良影响,增产幅度为18.8%～37.5%。     

Elevated CO<Subscript>2</Subscript> effects on nutrient competition between a C<Subscript>3</Subscript> crop (<Emphasis Type="Italic">Oryza sativa</Emphasis> L.) and a C<Subscript>4</Subscript> weed (<Emphasis Type="Italic">Echinochloa crusgalli</Emphasis> L.)

Rice (a C₃ crop) and barnyard grass (Echinochloa crusgalli L.) (a C₄ weed) were grown in a 1:1 mixture in a paddy field in ambient condition and with supplemented free air carbon dioxide enrichment (FACE, CO₂ concentration + 200 μmol mol⁻¹), in order to evaluate the impact of rising atmospheric carbon dioxide on nutrient competition between rice crop and weed. Results showed that elevated CO₂ significantly enhanced the biomass, tillers, leaf area index (LAI) and net assimilation rate (NAR) of rice, but reduced those of barnyard grass after elongation. Tissue nitrogen (N) concentrations were decreased in both competitors, but their phosphorus (P) and potassium (K) concentration were increased. The increase in tissue P concentration of rice was greater than that in barnyard grass. Furthermore, the absolute uptake of C, N, P, K by rice were increased while those of barnyard grass decreased. As a result, significant increase of the ratios of rice/barnyard grass of biomass and absolute nutrient uptake were observed under elevated CO₂. The results suggest that rising atmospheric CO₂ concentration could alter the competition between rice and barnyard grass in paddy fields in favor of rice. The ability of rice to compete more successfully for nitrogen and phosphorous under elevated CO₂ is likely an important factor underlying this response. More generally, the results suggest that elevated CO₂ may have varying implications on nutrient dynamics between different elements of overall plant biomass and the soil nutrients pool.     

Involvement of reactive oxygen species generated from melanin synthesis pathway in phytotoxicty of <Emphasis Type="SmallCaps">L</Emphasis>-Dopa

l-DOPA is an active allelochemical that inhibits plant growth. To determine whether the phytotoxicity is due to the reactive oxygen species generated during its oxidation to melanin, oxidative damage, melanin accumulation, and the effect of antioxidants on its phytotoxicity were examined in l-DOPA-tolerant (barnyard grass) and -susceptible (lettuce) plants, and in suspension-cultured carrot cells. l-DOPA suppressed root elongation in lettuce compared to barnyard grass. Levels of melanin and thiobarbituric acid reactive substances (TBARS) increased remarkably in l-DOPA-treated lettuce roots, but not in barnyard grass. l-DOPA also suppressed carrot cell growth to 60% of the control at 1 mM. Melanin content in 1 mM l-DOPA-treated carrot cells increased continuously; however, ascorbic acid and -tocopherol suppressed accumulation. When melanin formation was inhibited by ascorbic acid and -tocopherol, growth of l-DOPA-treated cells was restored. TBARS levels were higher in 1 mM l-DOPA-treated carrot cells than in untreated control cells 2 d after treatment, but not at 4 or 6 d. Ascorbic acid and -tocopherol suppressed the production of lipid peroxide during the initial 2 d. These results suggest that the phytotoxicity of l-DOPA is due to oxidative stress caused by reactive oxygen species from the melanin synthesis pathway.     

苯噻草胺的应用及合成工艺

苯噻草胺是一种低毒高效杀稗除草剂,在日本的应用面积达到110万公顷以上,近几年国内的许多研究单位和农药生产厂家也在对其进行开发。文中概述了苯噻草胺的性质、应用以及国内外的合成方法,重点介绍了淮阴电化厂开发的新工艺及其特点。该新工艺具有原料易得、成本低、产品质量优、工艺条件温和等优点,已经达到了国际先进水平。