绿黄隆对后茬水稻安全性探讨

磺酰脲类超高效麦田除草剂绿黄隆,控制本省太湖、丘陵、里下河地区稻茬麦田的主要杂草,经济有效,为目前其它麦田除草剂所不及。但绿磺隆持效期较长,对后茬水稻的安全性值得重视,作者等曾于1988—1990年进行这方面试验,现将3年研究结果报道如下。 一.材料与方法 1987—1990年在太湖地区农科所采取水泥地、盆栽与田问定位试验相结合的方法进行。水尼池试验微区面积1米~2,重复3次,盆钵试验,用30×30(厘米)盆钵,重复4-5次。设不施药和无草对照。大田试验各用量     

2种除草剂与增效酮梨混用对小麦田阔叶杂草的防除效果

采用田间药效试验方法,研究了增效酮梨与22%氯吡·苯·唑草可湿性粉剂、20%氯氟吡氧乙酸乳油2种除草剂混用对小麦田阔叶杂草的防除效果.结果表明,2种除草剂与供试增效剂混用可有效防除小麦田常见阔叶杂草.药后30d,各药剂处理对杂草防除效果最高,其中22%氯吡·苯·唑草可湿性粉剂加增效酮梨防效可达90.99%,药后45d鲜质量防效最高可达95.25%.2种除草剂的使用可提高小麦产量.     

防除玉米田苗后杂草除草剂的选择

玉米田杂草发生种类较多，危害重，本地区常年使用土壤封闭型除草剂在玉米播种后至出苗前喷雾来防除杂草，但因气候、除草剂特性等因素影响，玉米出苗后仍有许多杂草发生，并造成一定的危害。如何在玉米出苗后应用除草剂防除杂草，是需要解决的问题。     

防除大豆田阔叶杂草除草剂筛选试验报告

近年来 ,山东省大豆田应用较多的芽前除草剂以乙草胺为主 ,芽后除草剂有盖草能、禾草克、拿捕净等 ,这些除草剂对禾本科杂草有较好的防除效果 ,但都不能有效地控制铁苋菜、马齿苋、反枝苋等阔叶杂草的危害。因此 ,筛选适宜防除大豆田阔叶杂草的除草剂显得非常必要。我们于 1 999年进行了克莠灵、豆必乐、克阔乐、Ｃａｄｒｅ及豆草灭等除草剂对比试验。1　材料与方法1 .1　供试药剂供试药剂有 44%克莠灵水剂 (德国巴斯夫公司产 )、38%豆必乐水剂 (德国巴斯夫公司产 )、2 4%克阔乐乳油 (德国艾格夫公司产 )、2 4%Ｃａｄｒｅ水剂 (Ｉｍａｚｅｔ…     

75%二氯吡啶酸可溶性粒剂防除冬油菜田阔叶杂草效果

近年来由于种种原因,太湖地区冬油菜田恶性杂草稻槎菜种群数量不断上升,而一般除草剂对稻槎菜效果不太理想,已经影响了油菜的生产。75%二氯吡啶酸可溶性粒剂(clopyralid,龙拳)是陶氏益农公司最新研制开发的油菜田除草剂,对稻槎菜效果较好。为明确75%二氯吡啶酸防治冬油菜田阔叶杂草,特别是恶性杂草稻槎菜的效果,以及对作物的安全性,确定该产品的使用剂量和使用技术,进行了防治冬油菜田杂草的田间药效试验。1材料与方法1.1供试材料供试作物冬油菜品种为苏油1号。油菜田阔叶杂草以稻槎菜(Lapsana apogonoidesMaxim.)为主,其他包括野老鹳(Ger…     

洋葱育苗田杂草发生特点与防除技术

随着种植业结构的调整,我场秋播洋葱面积逐年增加,至1999年秋播时已发展至育苗田800亩。由于洋葱秧苗小,育苗田杂草密度大,人工除草困难,化学除草已势在必行。我们于1998～1999年对洋葱育苗田化学除草技术进行了研究,基本摸清了我场秋洋葱育苗田杂草发生的种类与消长规律,并经小区试验筛选出适宜的施田补等除草剂品种与配方。现将试验研究结果报告如下。1　材料与方法11　田间杂草发生规律调查洋葱出苗后选不同茬口田,每3ｄ1次调查记载杂草发生种类和数量。1.2　化除药剂筛选试验1.2.1　供试药剂　40%阿特拉津悬浮剂(吉林省吉林市农药厂产),…     

影响棉田鳢肠化除效果的因素初探

鳢肠(Eclipta prostrata)原为沿海棉区的潜在性杂草,近年来随着棉田防除单子叶杂草除草剂的运用和稻改棉的面积扩大,对棉花的为害有加重趋势。发生量大的田块每平方米有鳢肠高达288株,严重地影响了棉花产量。1991～1993年我们进行了鳢肠生物学特性及环境因素对化除效果影响的试验,并筛选对鳢肠防效较好的除草剂。 一、材料与方法 (一)供试药剂 供试药剂有50％扑草净和20％敌草胺,均为如东农药厂产。 (二)试验方法 1.鳢肠种子萌发条件试验     

大惠利防除花生田杂草试验

花生是我区主要经济作物,每年种植面积约在13.33万hm~2,杂草种类多,为害重,常因除草不及时,不彻底而形成草荒,造成减产。为了减轻杂草为害,提高花生产量,寻求高效、省工、安全的除草剂,我们于1992年对大惠利防除花生田杂草进行了试验,现将结果报道如下。 1 材料与方法 供试药剂为50％大惠利可湿性粉剂,英国卜内     

胡萝卜田苗后杂草化学防除药剂筛选

为探究安全、高效的胡萝卜田苗后杂草化学防除技术,采用盆钵法研究了13种苗后茎叶处理除草剂对胡萝卜的室内安全性,并对筛选得到的苗后除草剂进行了初步的田间药效及安全性试验。结果表明：供试13种除草剂中扑草净对胡萝卜的安全性较好,在225 g（a.i.）/hm²剂量下,胡萝卜苗的鲜重为53.61 g,与对照无显著差异,未出现药害反应;在450、750 g（a.i.）/hm²剂量下分别出现了1级和2级的低级别药害反应;而噁草酮、氰草津、嘧啶肟草醚、双草醚、辛酰溴苯腈、乙氧氟草醚、乙羧氟草醚、咪唑乙烟酸、灭草松、噻吩磺隆、双氟磺草胺和氯吡嘧磺隆在推荐剂量下,对胡萝卜鲜重抑制率为19.30%~100.00%,出现了3~5级的药害反应。扑草净对胡萝卜田杂草有较好的防效,在剂量为450~600 g（a.i.）/hm²时对胡萝卜田杂草总体的株防效和鲜重防效均达到80.56%以上,且对胡萝卜安全,无药害反应。胡萝卜田苗后杂草化学防除建议使用450~600 g（a.i.）/hm²扑草净进行茎叶喷雾处理,可达到对禾本科和阔叶杂草的有效防除,且对胡萝卜安全。     

18种茎叶处理除草剂紫花苜蓿田应用效果测定

紫花苜蓿是我国主要的牧草之一,为明确适合于紫花苜蓿田应用的除草剂,于2016年进行18种除草剂防除紫花苜蓿田杂草的效果及对紫花苜蓿安全性的试验测定。结果表明,紫花苜蓿对除草剂敏感度较高,供试的18种除草剂中仅有9种对紫花苜蓿安全,其中甲咪唑烟酸可以用于紫花苜蓿田防除禾本科或者阔叶杂草,对紫花苜蓿安全性好且杂草防除效果好;高效氟吡甲禾灵乳油、精喹禾灵和烯草酮这3种药剂可以用在以禾本科杂草为主的紫花苜蓿田;灭草松、唑嘧磺草胺、嗪草酸甲酯和扑草净等4种药剂对紫花苜蓿安全,对阔叶杂草防除效果好,但对禾本科杂草防除效果差或无效,可以应用在以阔叶杂草为主的紫花苜蓿田;另外的乙氧氟草醚等10种药剂不可应用在紫花苜蓿田。     

重视有害蚜虫研究,确保作物安全

<正>蚜虫隶属半翅目蚜虫总科,是世界上分布最广的微小昆虫之一。世界已知4 700余种,中国分布约1 100种[1-2]。蚜虫种类多、繁殖快、世代重叠,还存在孤雌生殖与两性生殖世代交替等独特生物学现象。许多蚜虫种类是非常重要的农作物害虫,其刺吸式口器可吸食植物汁液,造成植物生长不良,其唾液也对植物有毒害作用[3-4]。受蚜虫为害的植物具有多种不同症状,如生长率降低、产生叶斑、泛黄、发     

高原人体生理适应学理论在进藏旅游中的应用

青藏铁路的贯通运行,带来了国内外进藏旅游热.然而,青藏高原毕竟是世界屋脊,高海拔带来的低氧及其引发的高原疾病依然威胁着游客的身体健康.健康高原旅行是当前游客进藏旅游的基本前提,通过综合国内外高原医学工作者对高原医学生理学的研究成果,提出阶梯进藏旅游的方法.旨在对越来越多的短期赴西藏高原旅行的人群以正确的健康指导,从而减...     

稻瘟病菌对三环唑抗药性测定方法的建立

研究了稻瘟病菌对三环唑抗药性的测定方法,确定了保绿培养基的成分,建立了抗药性测定的标准化模型。4叶I心期将稻苗在三环唑系列浓度药液中浸根处理36 h,剪取稻苗叶段插于100 μg/mL苯并咪唑+0.5％水琼脂保绿培养基上,用孢子含量为10⁵个/mL的稻瘟病菌孢子悬浮液喷雾接种,保湿培养8 d后调查结果,计算EC₅₀值。该测定方法与小苗测定相比较结果更加稳定且灵敏度高,重复性好。     

白刺花(Sophoraviciifolia)适应土壤干旱的生理学机制

用盆栽的方法人工控制土壤干旱条件,研究白刺花天然实生幼苗适应土壤干旱的生理学机制。结果表明:随土壤含水量的减少,白刺花叶水势在胁迫前期下降缓慢,随胁迫时间的延长,水势大幅度下降。白刺花通过在叶片内积累大量渗透保护性物质可溶性糖和K ,增加细胞的保水力,维持细胞生长所需膨压。白刺花游离脯氨酸含量变化与水分关系不大,可溶性蛋白质含量随土壤含水量减少而下降,可能是水分胁迫下受伤害的表现。随土壤水分含量的减少,白刺花SOD的活性明显升高,POD活性不高但随胁迫时间延长其活性较稳定,CAT活性下降但幅度不大,且CAT活性变化趋势与POD活性相反,说明三个保护酶能够相互配合协同作用,降低膜脂过氧化程度,减少水分胁迫造成的伤害,提高质膜稳定性,维持细胞膜的完整性,表现出很强的抗旱适应性。     

Heritability of Ulmus minor resistance to Dutch elm disease and its relationship to vessel size,but not to xylem vulnerability to drought

Dutch elm disease (DED) is a vascular wilt disease that causes the occlusion and cavitation of xylem vessels. Therefore, it is hypothesized that those elms that are less vulnerable to cavitation by drought might be more resistant to DED. To test this hypothesis, the relationship between xylem vulnerability to cavitation and susceptibility to DED was examined in progenies of crosses between susceptible and resistant individuals of Ulmus minor. Hydraulic conductivity and xylem vulnerability curves were evaluated and anatomical features such as vessel size, length and grouping were measured. Next, elms were inoculated with Ophiostoma novo‐ulmi, the cause of DED, and pre‐dawn and midday water potentials, stomatal conductance and wilting percentages were assessed. Progenies of R × R crosses showed significantly lower mean wilting percentages (30–50%) than the progeny of S × S crosses (75%). Fifty percent conductivity loss was reached at c. ?1 MPa, pointing out a high vulnerability of this species to drought‐induced cavitation. Crown wilting percentage as a result of inoculation and xylem vulnerability to cavitation by water stress did not show any significant correlation. Nevertheless, significant differences in theoretical hydraulic conductivity and vessel size parameters (diameter, length and size distributions) were found among the tested progenies. Susceptible trees had significantly wider and longer vessels. Xylem structure of resistant elms seems to restrict pathogen spread rather than prevent cavitation.     

Contribution of Fimbrial and Afimbrial Adhesins of Xylella fastidiosa to Attachment to Surfaces and Virulence to Grape

ABSTRACT The role of fimbrial and afimbrial adhesins of Xylella fastidiosa in biofilm formation was assessed by visualization of cell aggregates of mutant strains after incubation on glass surfaces. FimA- or FimF- fimbrial mutants adhered as solitary cells at a slightly lesser frequency to glass surfaces than the parental strain; however, cell aggregates were not formed, unlike the wild-type strain. Conversely, whereas the XadA- and HxfB- nonfimbrial mutants also exhibited a much lower frequency of adherence to glass surfaces than the wild-type strain, most of the cells retained on the surfaces were in cell aggregates of different sizes, much like that of the parental strain. Neither fimbrial or afimbrial mutants formed a mature biofilm on the sides of flasks of broth cultures, unlike the dense biofilm formed by the wild-type strain. Although FimA- and FimF- mutants did not form cell aggregates on glass surfaces when incubated as individual strains, aggregates of a FimA- or FimF- mutant were observed when co-incubated with either a XadA- mutant or HxfB- mutant, respectively. These results are consistent with a model in which the fimbrial adhesins FimA and FimF are involved preferentially in cell-to-cell aggregate formation whereas the afimbrial adhesions XadA and HxfB preferentially contribute to initial cell binding to surfaces, whereupon further cell aggregation can occur. In each of five separate experiments, FimA, FimF, XadA, and HxfB mutants of X. fastidiosa all were less virulent to grape than the corresponding wild-type strain. Fimbrial and afimbrial mutants might produce a reduced biofilm within vessels of grape and, hence, be deficient in various cell-density-dependent traits required for movement through the plant and, thus, virulence.     

Note to chew on: insect damage to musical instruments

Insects have a diverse range of ecologies that leaves many pre‐adapted to exploiting manufactured products as food sources, including musical instruments. To review what is known and to make recommendations for preventing and managing insect damage to musical instruments, we conducted a systematic search and a narrative review of the area. Of 339 papers, only eight peer‐reviewed publications met the inclusion criteria, and all were on xylophagous insects causing damage to wooden instruments. To supplement this material, we report a case of damage to the key pads (composed of felt enclosed in fish buoyancy bladder skin) of a clarinet by carpet beetles (Anthrenus verbasci (Dermestidae)), the first reported case of non‐woody damage and the first instance of insect damage rendering an instrument unplayable. To avoid such damage, regular inspection of instruments is recommended, and rapid treatment of any insect infestations in the immediate environment that could extend to affecting stored instruments. Instruments themselves can be extremely expensive, and if insects are still present these should only be treated by an expert; instrument cases can be more easily dealt with by heat treatment (black plastic bag in the sun) or application of a residual insecticide. © 2020 Society of Chemical Industry     

A grower-friendly method to transfer predacious mites to commercial orchards

The establishment of predacious mites in commercial orchards may be accelerated by the transfer of pruned wood in winter and summer from donor orchards to release orchards. Following winter pruning, 3-year-old and older wood is collected and transported as soon as possible in bundles to a release orchard for distribution. If the release orchard is composed of dwarf trees, then one or two bundles of 5 kg each are placed vertically at the base of the trunk of every tree in the block (0.5 to 1 ha); if the trees are of standard size, then four or five bundles used. Following summer pruning, annual shoots and suckers are distributed immediately in a release orchard composed of dwarf trees by placing 12–15 branches on the foliage of fruit-bearing branches; if the release orchard is composed of standard trees, then 50 branches are used. The pruned wood should have 20–25 leaves and not less than one predator per leaf. The release orchard should have a light infestation (two or three mites per leaf) of pest tetranychids. These phytophagous mites would serve as food and help establish the predators. The release orchard grower should develop a pest management program based on the same groups of pesticides used in the donor orchard. http://www.phytoparasitica.org posting Aug. 31, 2005.     

Acknowledgment to Reviewers

Journal of General Plant Pathology -