高效液相色谱串联质谱法测定小麦和土壤中的丁硫克百威及其代谢物

建立高效液相色谱-四级杆串联质谱快速测定小麦植株、土壤和麦粒中的丁硫克百威、克百威以及土壤中3-羟基克百威的检测方法。样品经提取、分散固相萃取净化后采用同位素内标法进行多反应监测模式测定。结果表明,该方法目标物在三种基质中的定量限为5μg/kg,回收率在73.7%~98.6%之间,变异系数在1.3%~3.3%之间,满足残留检测方法的要求。     

蚜虱净拌种防治单晚直播田稻蓟马试验初报

应用克百威防治水稻直播田苗期害虫,不仅成本高,而且对人、畜毒性大,对环境污染严重,不符合生产无公害稻米的发展方向。而目前市场上能替代克百威防治水稻直播田苗期害虫的药剂较少,且防效不够稳定。为了寻找替代克百威防治稻蓟马的理想药剂,我们对10%蚜虱净粉剂等几种杀虫剂进     

甲霜·种菌唑4.23%微乳剂对玉米苗期茎基腐病的防治效果

研究了甲霜·种菌唑4.23%微乳剂种子处理对玉米苗期病害茎基腐病的防治效果。结果表明:甲霜.种菌唑4.23%微乳剂3.375、4.5、5.4g a.i./100kg种子包衣不仅对玉米出苗和生长无不良影响,而且对玉米出苗和生长具有一定促进作用,出苗率和田间长势、株高较空白对照提高了1%以上,3种剂量包衣种子对玉米茎基腐病均具有良好的防治效果,平均防效在75%以上,其中以5.4g/100kg种子包衣的防治效果最高,防效达到82.98%。     

甲霜·种菌唑4.23%徽乳剂对玉米苗期茎基腐病的防治效果

研究了甲霜.种菌唑4.23%微乳剂种子处理对玉米苗期病害茎基腐病的防治效果.结果表明:甲霜·种菌唑4.23%微乳剂3.375、4.5、5.4g a.i./100kg种子包衣不仅对玉米出苗和生长无不良影响,而且对玉米出苗和生长具有一定促进作用,出苗率和田间长势、株高较空白对照提高了1%以上,3种剂量包衣种子对玉米茎基腐病均具有良好的防治效果,平均防效在75%以上,其中以5.4g/100kg种子包衣的防治效果最高,防效达到82.98%.     

三种内吸性杀虫剂对棉花多酚氧化酶 和羧酸酯酶活性的影响

用含不同浓度氧化乐果、吡虫啉和丁硫克百威的营养液分别处理棉花幼苗,研究不同处理时间其多酚氧化酶和羧酸酯酶活性的变化。结果表明,3种内吸性杀虫剂对两种酶活性的影响不仅与药剂种类有关,还具有一定的剂量效应和时间效应。400 mg/L 氧化乐果处理后24 h,棉花幼苗中多酚氧化酶活性比对照降低21.6%; 50 mg/L吡虫啉处理后120 h,多酚氧化酶活性比对照增 高47.3%; 200 mg/L丁硫克百威处理后72 h,多酚氧化酶活性增高75.7%。氧化乐果处理后120 h 内,各处理羧酸酯酶的活性均低于对照,且抑制率在70%以上; 50 mg/L吡虫啉处理后120 h,羧酸酯酶活性比对照增高30.7%;丁硫克百威处理后120 h内,羧酸酯酶活性与对照比较均无显著差异。     

烟草中安克力及其代谢物的残留分析

本文介绍了采用毛细管气相色谱法测定烟草中安克力(丙硫克百威)及其代谢物克百威、3-羟基克百威的残留分析方法。采用SP-502气相色谱仪 ,NPD检测器 ,OV-101毛细管柱(30m×0.53mm) ,测得在烟草中最低检出浓度为丙硫克百威0.003mg/kg、克百威0.001mg/kg、3-羟基克百威0.003mg/kg;最小检出量为丙硫克百威5×10-11g、克百威为3×10-11g、3-羟基克百威为5×10-11g。     

冠菌素对玉米苗期植株形态建成的调控效应

以玉米品种金海5号为材料,采用不同浓度植物生长调节剂冠菌素(COR)拌种和三叶期(V3)叶面喷施的方法,研究了COR对玉米苗期植株地上部和根系形态建成的影响,分析了其对叶面积、叶绿素含量和可溶性蛋白的调控效应。结果表明:不同浓度冠菌素对玉米幼苗形态建成的调控呈单峰曲线,即低浓度下促进幼苗生长,高浓度下抑制生长。用0.1 mg/L的COR拌种或叶面喷施处理,可促进玉米苗期植株株高和茎粗生长,增加单株叶面积,提高叶片叶绿素和可溶性蛋白含量,促进植株干物质积累。同时,COR可促进玉米苗期根系生长,增加根长和根表面积,进而可有效增加根系吸收能力。研究结果表明,适宜浓度的COR处理可以提高玉米幼苗光合性能,增强根系吸收能力,促进植株地上部和地下部的生长,有利于培育壮苗。     

克百威丙硫克百威和丁硫克百威的残留与降解研究进展

本文综述了近几年国内外对克百威、丙硫克百威、丁硫克百威的降解残留的重要进展，阐述了它们的降解和残留与其施用量、土壤类型、温湿度、降雨量等有关，它们的降解方式主要有水解、光解、微生物分解3种方式，指出了当前用于检测其残留量一些常用方法。     

加速溶剂萃取-液相色谱-串联质谱法同步检测白菜中的丁硫克百威及其代谢物残留

建立了白菜中丁硫克百威及其代谢物克百威、3-羟基克百威和3-酮基克百威的同步检测方法。白菜样品匀浆后用硅藻土混合分散,经加速溶剂萃取仪(ASE)用二氯甲烷萃取,固相萃取柱净化,在液相色谱-串联质谱(LC-MS/MS)仪上采用正电离方式以多反应监测模式(MRM)检测,内标法定量。丁硫克百威及其3种代谢物在白菜中的平均回收率在85%～122%之间,相对标准偏差为2.3%～12.5%,检出限为0.002～0.01 mg/kg,定量限为0.005～0.02 mg/kg。采用该方法测定的消解动态结果表明:丁硫克百威在白菜中的消解半衰期为0.9 d,代谢物克百威在施药当天即达到最大值,并在1 d内消解70%以上,而3-羟基克百威与3-酮基克百威的浓度则在1 d时达到最大值,然后呈现快速降低的趋势。     

丁硫克百威在桃果实上残留的消解动态

每公顷桃园施用氨基甲酸酯杀虫剂了硫克百威（carbosulfan）乳油2kg（有效成分）进行其消解动态研究，结果表明：丁硫克百威的降解主要发生在两个连续的阶段（0～28天和28～57天），半衰期分别为7．4天和17．5天；施药后57天的残留量低于0．2ma／kg；果实成熟采收期前30、21、14天进行两种用药量（商品量1:0和2.0g／L）和两种喷洒量（750和1500L／ha）施药处理，测定其残留量介于0．122mg／ks（采收前30天）和0．4mg／kg（采收前14天）之间；整个试验中，丁硫克百威的主要代谢物克百威（carbofuran）的含量低于其检测极限值0.004mg／kg．     

己酸二乙氨基乙醇酯缓解氯磺隆对玉米药害的研究

采用室内土培法分别测定了不同浓度己酸二乙氨基乙醇酯（简称DA-6）和不同浓度氯磺隆对玉米生长的影响,不同浓度氯磺隆处理土壤DA-6浸种对玉米根生长的影响。结果表明DA-6浓度在0.5～20mg/L范围内,玉米根长、根鲜重和株高、株鲜重高于对照,其中以5mg/L最好;氯磺隆处理浓度自0.25μg/kg起,明显抑制玉米幼苗的生长,且对主根长和根鲜重的抑制作用较株高和株鲜重更为严重;当用5 mg/L的DA-6浸种可不同程度地缓解0.25～8μg/kg的氯磺隆对玉米的伤害。     

Induction of phenylalanine ammonia-lyase (PAL) in insect damaged and neighboring undamaged cotton and maize seedlings

There has been scepticism about plants responding to information from their damaged neighbor plants since it was first reported, although a growing body of evidence indicates that interplant communication may play a key role in the resistance of plants. Cotton aphids and corn borer are important insects in cotton and maize, respectively. The resistance of healthy cotton and maize plants induced by their neighbor damaged plants was investigated in this study. Phenylalanine ammonia-lyase (PAL) is a chemical marker of induced resistance in many plants. The enzymatic activity and gene expression of PAL were determined in cotton and maize seedlings damaged by wounding, aphid and corn borer attack and in intact undamaged maize and cotton seedlings growing nearby. The enzymatic activity and gene expression of PAL were significantly increased in the cotton and corn seedlings damaged by wounding or by aphid and corn borer. Furthermore, undamaged neighboring cotton and maize seedlings also showed elevated enzymatic activity and gene expression of PAL. These inductions of PAL enzymatic activity and gene expression in the damaged and undamaged seedlings suggest inter-species communication between cotton and maize.     

河南北部稻蛀茎夜蛾为害夏玉米苗初报

在河南省新乡市发现夏玉米苗受稻蛀茎夜蛾为害,本文首次报道了该虫在中国黄淮海夏玉米区发生及对夏玉米苗的为害,并简要描述其为害特点以及生活习性。为进一步研究其在夏玉米区耕作制度下的生物学特性及防治技术提供重要基础。     

The basis for the safening of clomazone by phorate insecticide in cotton and inhibitors of cytochrome P450s

Clomazone may be safely used in cotton to manage weeds when applied following treatments of the organophosphate insecticides phorate or disulfoton. The loss of chlorophyll and carotenoids with 6 days of 100 nM clomazone treatment of cotton seedlings was partially prevented with phorate in hydroponic solution in a rate-dependent manner. In a study to examine the timing of safening from a one-day clomazone (100 nM) treatment, maximum safening was achieved when phorate (50 μM) was applied the same day as clomazone. Phorate decreased metabolism of ¹⁴C-clomazone to polar metabolites in excised cotton shoots and shoots of intact cotton plants. Microsomal studies of corn shoots showed an NADPH-dependent/cytochrome P450 reaction was inhibited by phorate. Additional studies with corn microsomes, corn seedlings and cotton seedlings supported the basis of clomazone safening is the inhibition of toxic clomazone metabolism by P450 inhibitors.     

玉米矮化病株及其根际土壤内线虫的分离与分子鉴定

为探究玉米矮化病的病原,采用Ludox TM悬浮法对从吉林和辽宁采集的玉米矮化病株及其根际土壤和健康株根际土壤分离的线虫进行了鉴定和种群比较,并对矮化病株茎基组织PCR产物进行测序分析。结果表明:玉米健康株根际土壤分离出29属线虫,特有线虫是角咽线虫属Actinolaimus和木盾移线虫属Peltamigratus,矮化玉米病株根际土壤分离出28属线虫,特有线虫为锥线虫属Dolichorus,二者相同的线虫属有27个。矮化玉米病株根际土壤中植物线虫种类和数量明显比健康株根际土壤中高,线虫种群数量差异明显的主要是矮化线虫属Tylenchorhynchus、短体线虫属Pratylenchus和刺线虫属Belonolaimus,病株根际土壤中这3个属线虫总数约占病株土壤分离线虫总数的20.23%、11.27%和10.40%。玉米矮化病株茎基组织中短体线虫属和矮化线虫属数量占优势,2个属的线虫数量分别占测序总数的22%、14%(吉林长岭)和16%、20%(辽宁黑山)。表明玉米矮化病的发生与植物线虫相关,很可能是多种线虫共同引起的病害。     

Effects of aqueous extracts and decomposition of Mikania micrantha H.B.K. debris on selected agronomic crops

Laboratory and greenhouse experiments were conducted to determine the effects of aqueous extract and the debris of Mile-a-Minute ( Mikania micrantha H.B.K.) on the germination and growth of four test species, viz. tomato ( Lycopersicon esculentum Mill.), Chinese cabbage ( Brassica chinensis L.), corn ( Zea mays L.) and long bean ( Vigna sesquipedalis L.). Germination percentage, radicle length and fresh weight of two crops, Chinese cabbage and tomato, decreased progressively when plants were exposed to increasing concentrations (12.5, 25, 37.5 and 50 g L⁻¹) of aqueous extract of Mikania , but did not affect those of corn and long bean seedlings. The emergence of tomato and Chinese cabbage was greatly reduced when Mikania debris was incorporated into the soil, irrespective of the amount of debris and the decomposition period. In contrast, the emergence of corn and long bean seedlings was not affected. The application of fertilizer (NPK 15 : 15 : 15) enhanced the fresh weight of all seedlings tested as compared with those not supplied with the fertilizer. Four compounds were identified in the leaf extract of Mikania , viz. caffeic acid, p -hydroxybenzaldehyde, resorcinol and vanillic acid.     

Activity of glutathione S-transferase toward some herbicides and its regulation by benoxacor in non-embryogenic callus and in vitro regenerated tissues of Zea mays

A procedure was developed to obtain non-embryogenic callus and regenerated lines from root segments of Zea mays grown in aseptic conditions. The activity of glutathione-S-transferases (GSTs), for non-embryogenic callus, was determined toward 1-chloro-2,4-dinitrobenzene (CDNB) and it was compared with that obtained for corn seedlings grown without hormones. For the callus masses, increases of specific activity toward CDNB and the kinetic parameter V_max were observed with respect to corn seedlings. The procedure permitted the regenerating of tissues from callus explants, therefore the GST(CDNB) activity and the effect of the safener benoxacor on its expression were investigated for the regenerated tissues grown in agarized substrate and in liquid medium. These explants showed a constitutive GST(CDNB) activity higher than corn seedlings and this activity was increased, for both tissues, in response to the presence of the safener benoxacor in the growing medium. The GST activity for the above tissues was also assayed toward benoxacor and terbuthylazine, metolachlor and fluorodifen herbicides. Measurable GST activity was found toward some of the above chemicals and it was found to be significantly enhanced in response to benoxacor treatment.     

安徽省玉米主要害虫种类与发生为害初探

系统调查了安徽省不同地区、玉米不同生育期害虫种类及发生为害情况。调查发现:安徽省全境玉米适生期长,玉米种植结构复杂,北部地区以连片种植夏玉米为主,南部地区以插花式播种春玉米为主。与为害夏玉米的害虫相比,南部春玉米害虫种类更为多样。亚洲玉米螟Ostrinia furnacalis(Guenée)是全省玉米的主要害虫,其中铜陵地区春玉米苗期受亚洲玉米螟为害最重,被害株率达25.6%。蜗牛在夏玉米穗期和春玉米苗期为害严重,部分田块被害株率达100%。桃蛀螟Conogethes punctiferalis(Guenée)是春、夏玉米穗期的另一主要害虫,常与亚洲玉米螟、棉铃虫Helicoverpa armigera(Hübner)和黏虫Mythimna separata(Walker)混合发生,但在淮北地区玉米秸秆中未发现冬后存活的桃蛀螟幼虫。     

鲜食玉米品种心叶期对草地贪夜蛾抗性评价及不同品种受害后的产量损失

为初步探究鲜食玉米对草地贪夜蛾 Spodoptera frugiperda的抗性水平, 在田间草地贪夜蛾自然发生条件下对28个不同类型(甜玉米10个、甜糯玉米8个、糯玉米10个)的鲜食玉米品种进行了心叶期抗虫性鉴定, 研究了不同抗性水平及不同类型鲜食玉米的产量损失; 在室内研究了取食不同品种玉米苗对草地贪夜蛾幼虫发育历期的影响。经鉴定, 28个品种中无高抗及抗虫品种, 中抗品种12个, 感虫品种15个, 高感品种1个, 分别占鉴定资源总数的42.86%、53.57%和3.57%。28个品种的产量损失为8.30%~40.93%, 室内喂饲后幼虫的发育历期为11.29～15.31 d。不同类型鲜食玉米的叶部受害级别、产量损失和草地贪夜蛾幼虫发育历期无显著差异。甜玉米、糯玉米的叶部受害级别与产量损失呈正相关, 相关系数分别为0.61和0.79, 甜糯玉米的叶部受害级别与产量损失不相关。     

转Bt基因玉米对粘虫的室内杀虫效果评价

在室内用生测法研究了表达Cry1Ab杀虫蛋白的Bt玉米MON810和Bt11小苗和心叶对粘虫Mythimna separata (Walker)初孵幼虫以及玉米叶片对暴食期4龄和5龄幼虫的杀虫效果.结果表明,2种Bt玉米小苗及心叶对粘虫初孵幼虫都具有很好的控制效果,取食MON810和Bt11小苗的粘虫初孵幼虫第1 天的存活率分别为69.44%和86.11%,到第3 天时,取食Bt11小苗的幼虫全部死亡,此时取食MON810小苗的幼虫存活率仅为4.17%,到第7 天全部死亡,而此时在各自相对应的对照玉米DK647和NX4906小苗上幼虫存活率分别为91.66%和88.89%.取食MON810和Bt11心叶的粘虫初孵幼虫第2 天时幼虫存活率急剧下降,分别为13.89%和19.45%,到第7 天时,取食两种Bt玉米心叶的初孵幼虫全部死亡,而取食对照玉米心叶幼虫存活率分别为94.45%和97.22%,差异极显著.两种Bt玉米对粘虫4龄幼虫有很好的杀虫效果,取食的第11天 4龄幼虫全部死亡,对照幼虫存活率均为100%;在Bt11和MON810叶片上取食的粘虫5龄幼虫也不能存活,分别在取食的第11天和12天全部死亡,对照存活率分别为96.00%和98.00%,差异极显著.表明Bt玉米对粘虫初孵幼虫和暴食期的4龄和5龄粘虫都具有显著的致死作用.