陕西关中西部麦田禾本科杂草发生态势及控制技术

近几年,陕西省关中西部麦田禾本科杂草的分布区域和田间密度呈明显上升趋势。据在宝鸡市岐山县调查,20世纪80年代,野燕麦仅在渭河两岸麦田零星发生,到目前已蔓延到塬区和旱地,且基数逐年增加。2001年,恶性杂草节节麦也在塬灌区麦田首次发现。全县麦田杂草群落出现了由单一的阔叶类杂草到阔叶类与禾本科杂草混合发生的态势,成为小麦生产中的一大公害,已对粮食生产和农业生态安全构成了严重威胁。1发生现状及特点据在岐山县蔡家坡、雍川、益店、凤鸣、大营、蒲村等6个乡(镇)80块麦田调查,有野燕麦的29块,有节节麦的19块,二者混合发生的17块,草…     

河北省麦田节节麦等杂草发生特点及治理对策

河北省常年种植冬小麦250万hm2。长期以来,并未发现节节麦(A egilops squarrosa L.)、雀麦(B rom us japonicus Thunb.)等禾本科杂草在麦田造成危害。2001年,在盐山县麦田首次发现节节麦危害;2002年,在定州市麦田首次发现雀麦危害。从全省调查结果看,目前常发性杂草仍以播娘蒿、荠菜、麦瓶草为主,但节节麦、雀麦等恶性禾本科杂草在部分地块已成为优势种,并造成严重为害。2004年调查,节节麦、雀麦已经成为本省小麦稳产、高产的严重威胁。1麦田禾本科杂草的发生特点1郾1发生面积大节节麦和雀麦的发生面积在首次发现时,均不足600m2,而目前已…     

麦田恶性杂草节节麦和雀麦的发生特点及防治对策

冀州市常年小麦种植面积为2万hm^2,历年以来,并未发现节节麦、雀麦等禾本科杂草在麦田造成危害。2002年首次发现节节麦危害,之后逐年增多,到2008年发生面积达1,4万hm^2,其中重发生面积2666.7hm^2,发生范围已遍及全市11个乡镇,全市草田率38.5％,一般密度每m^2为2.3株,最高密度7.2株。从调查情况看,目前节节麦、雀麦恶性杂草虽然密度较低,但由于该草多发生在高水肥麦田,适应性强,繁殖快,发生面积不断扩大,危害逐年加重,部分麦田已成为优势杂草种群,对冀州市的小麦生产已构成严重威胁。     

警惕麦田恶性杂草节节麦蔓延危害

节节麦是一种进境危险性植物杂草,近年来在河北等省区麦田发生危害,面积迅速扩大,以目前节节麦传播蔓延的速度,节节麦将在各适生区域泛滥成灾,严重威胁我国小麦安全生产和粮食安全。在调查研究的基础上,全面分析了节节麦的来源和成灾原因,提出了应急措施和控制节节麦危害蔓延的建议。     

2021年麦田杂草科学防控技术方案

麦田杂草重点防控节节麦、看麦娘属、雀麦、菵草等禾本科杂草,播娘蒿、猪殃殃等阔叶杂草。要立足麦草秋防、综合防控,根据小麦种植区域、杂草种类与分布特点,开展分类指导。一是非化学控草技术。精选种子。通过对麦种调入和调出检疫,检查其中是否夹带杂草种子,特别是毒麦、节节麦、野燕麦等。农业措施。     

新疆核桃-小麦间作麦田杂草组成及群落特征

为明确新疆核桃与小麦间作对麦田杂草种类及群落结构的影响,于2012—2017年对新疆南疆核桃-小麦间作、单作麦田杂草发生情况进行了调查。结果表明,南疆麦区杂草有39种,隶属14科33属,其中以菊科、禾本科、藜科为主;优势杂草有9种,分别是灰绿藜Chenopodium glaucum L.、稗草Echinochloa crusgalli(L.)Beauv.、播娘蒿Descurainia sophia(L.)Schur.、扁蓄Polygonum aviculare L.、硬草Sclerochloa kengiana L.、田旋花Convolvulus arvensis L.、离蕊芥Malcolmia africana(L.)R. Br.、小蓟Cephalanoplos segetum(Bunge.)Kitam.、苣荬菜Sonchus brachyotus DC.;与小麦单作田相比,核桃-小麦间作麦田杂草物种丰富度及Shannon-Wiener指数较高,2017年物种丰富度最高达27种,代表杂草优势集中性的Simpson指数则是小麦单作田高于核桃-小麦间作麦田,2013年高达0.32;核桃-小麦间作有利于麦田播娘蒿、苣荬菜和离蕊芥发生,但不利于萹蓄发生,其它5种优势杂草在间作和单作麦田的发生密度无显著差异。     

节节麦在我国的分布及其研究概况

节节麦(Aegilops tauschii Coss.)为北方麦田恶性杂草之一,由于其为小麦D染色体组的供体,选择性化学防治难度较大,发生严重的地块影响小麦产量和品质。综述节节麦在我国的分布及危害,并从节节麦生物学特性、与小麦的竞争、遗传多样性、防除与利用现状等方面阐述其研究概况,展望节节麦在杂草防控方面的研究方向,以期为节节麦化学防治及综合防控研究奠定基础。     

36%甲基碘磺隆钠盐·甲基二磺隆可分散粒剂防除麦田禾本科恶性杂草节节麦推广应用

本文记述了临汾市植保部门秋末和初春应用新型除草剂3.6%甲基碘磺隆钠盐·甲基二磺隆可分散粒剂防治麦田节节麦、雀麦等禾本科恶性杂草的防效情况,以及不同用量、不同时间的药效情况.并提出了宜秋末冬前推广使用的建议.     

鲁西南地区麦田杂草发生现状调查及防除措施

近年来,鲁西南地区麦田杂草发生严重,为摸清麦田杂草发生现状并提出针对性防控建议,运用倒置"W"9点取样法对邹城市麦田杂草发生情况进行调查。结果表明,危害麦田的杂草涵盖14科31种,其中以禾本科、茜草科杂草的危害性较大,优势种为节节麦、雀麦、播娘蒿、猪殃殃。针对邹城市麦田杂草发生现状,笔者提出了鲁西南地区麦田杂草的针对性防控建议。     

陕西省小麦主产区麦田杂草发生及危害情况调查

采取倒置W 9点取样法对陕西省小麦主产区的麦田杂草进行了调查,明确了主产区麦田杂草的发生种类及优势杂草的危害趋势。调查到麦田杂草共49种,隶属于21科。其中,禾本科杂草占30%,阔叶杂草占70%。优势杂草有节节麦、多花黑麦草、野燕麦、看麦娘、鬼蜡烛、播娘蒿、猪殃殃、婆婆纳、蓟、荠等10种。禾本科杂草占生长优势,阔叶类杂草占数量优势。节节麦近年来危害迅速加大,成为麦田恶性禾本科杂草。阔叶杂草对常年使用的苯磺隆等药剂已经产生抗药性,防控效果降低。     

Roles of flavoproteins in degradation of mexacarbate in rats

The nature of a reductive system which actively degrades mexacarbate in the rat intestine and liver was investigated. The system is characterized by its stability against heat and protease treatments and its requirements for a flavin cofactor and an acidic pH for a maximum activity. As a result of purification and spectroscopic identification attempts the system responsible for the above reductive activity was identified to be flavoprotein. Under anerobic conditions such flavoproteinflavin cofactor systems degrade mexacarbate first to 4-N-desmethylmexacarbate and then to polar water-soluble metabolites.     

祁连山老虎沟地区高寒草甸蒸散发估算

利用祁连山老虎沟地区海拔4200m气象观测站2010年的观测资料,采用FAO Penman-Monteith公式,再利用作物系数法,对高寒草甸生长季(5月22-9月22)的蒸散发量进行估算和分析。结果发现:研究期共有124天,蒸散发总量为238.3mm,日均为1.87mm·d-1。生长初期、生长中期、生长末期的蒸散发总量依次为22.6mm,179.1mm,36.6mm,依次占研究期总量的8.4%,75.2%,15.3%。5月下旬至6月中旬,日均蒸散发量以较低水平缓慢上升;6月下旬迅速增加;6月末至7月中旬猛然回落;7月中旬至8月末,日均蒸散发量迅速上升且维持在较高水平;此后直到9月22日,缓慢减少。5-9月月蒸散发总量依次为6.6mm,46.4mm,74.5mm,77.6mm,33.1mm。     

Aetiology of Rhizoctonia in sheath blight of maize in Sichuan

Rhizoctonia isolates obtained from maize grown in commercial fields in 33 representative counties (or cities) in Sichuan province in China were characterized according to colony morphology, hyphal anastomosis and pathogenicity. Of 141 isolates, 116 were identified as R. solani , 23 as R. zeae and two as binucleate Rhizoctonia . The isolates of R. solani were assigned to four anastomosis groups (AG): AG-1-IA (101 isolates, accounting for 71.6% of the total), AG-1-IB (2, 1.4%), AG-4 (9, 6.4%) and AG-5 (4, 2.8%). The two isolates of binucleate Rhizoctonia belonged to AG-K. On maize, isolates of AG-1-IA caused typical sheath blight symptoms. Lesions produced by isolates of AG-4, AG-5, AG-1-IB and AG-K were darker than those of AG-1-IA. Rhizoctonia zeae usually caused discontinuous lesions with a dark brown margin and a brown centre on the leaf sheaths, as well as ear rot. Isolates of AG-1-IA were the most virulent to maize, with an average lesion length of approximately 15 cm. Isolates of R. zeae produced lesions approximately 12 cm long, while those of AG-4, AG-5, AG-1-IB and AG-K were progressively shorter. On potato dextrose agar (PDA; pH 6.4), the minimum temperature for mycelial growth of R. zeae isolates was 14–18°C, the maximum 38–40°C and optimum 30°C. Isolates of R. zeae did not grow on PDA (28°C) at pH 2.0, the optimum for growth being pH 6.4.     

西北地区冬季室内三种常绿植物的光合特性比较

使用Li-6400XT便携式气体交换系统的红蓝光源和液化CO_2钢瓶注入系统,模拟冬季室内较密闭环境下存在较高CO_2浓度且为弱光环境,设置CO_2浓度为600μmol·mol~(-1),并以400μmol·mol~(-1)作为对照组(CK),对绿萝(Scindapsus aureus)、鹅掌柴(Scheffera octophlla(Lour).Harins)和燕子掌(Crassula agenten Thunb.)进行光响应(Pn-PAR)曲线的测定。结果显示:在CO_2浓度600μmol·mol~(-1)下,三种植物的光饱和点(LSP)均比(CK)更早出现,绿萝和鹅掌柴总体的净光合速率(Pn)比(CK)高,燕子掌比(CK)低;绿萝的最大光合速率(Pmax)、光饱和点(LSP)和表观量子效率(YAQ)均最高,分别为5.62±0.145μmol·m~(-2)·s~(-1)、373.51±24.15μmol·m~(-2)·s~(-1)和0.041±0.003μmol·μmol~(-1),但暗呼吸速率(Rd)较低(-0.51±0.14μmol·m~(-2)·s~(-1));鹅掌柴和绿萝的水分利用率(WUE)和蒸腾速率(Tr),极显著高于燕子掌(P<0.01);绿萝的叶绿素SPAD值最高(70.03±4.18),极显著高于其余两种(P<0.01)。研究表明,绿萝对光照具有最强的利用能力,且能在高CO_2浓度且干旱的环境里健康生长,并能对室内环境起到较强的增湿效应,是西北地区冬季较为理想的室内植物。     

山西省2012年蔬菜农药残留监测结果分析

本文通过对2012年山西省蔬菜农药残留监测结果的分析,找出造成山西蔬菜农药残留问题原因,并针对性的提出了解决问题的对策,为蔬菜生产提供依据。     

环流特征量指数在新疆汛期降水趋势预测中的应用

利用中国气象局气候中心下发的74类环流特征量值,通过相关分析,建立了新疆10个区域的汛期降水预测模型。结果表明:预测模型对新疆汛期降水趋势有一定的预报能力,尤其是在新疆洪涝灾害多发的伊犁及博尔塔拉蒙古自治州、北疆沿天山一带、天山山区,建立的3个区域预测模型可以作为汛期降水预测的主要工具。     

Incidence of benomyl and iprodione resistance in isolates of Botrytis cinerea in tomato crops in England and Wales in 1986

In 1986, mass-mycelial isolates of Botrytis cinerea from 67 tomato crops in England and Wales were examined for benomyl and iprodione resistance. Of the 706 isolates obtained, 62.7% were resistant to benomyl at 2μg/ml and 43.2% were resistant to iprodione at 2 μg/ml. Iprodione resistance persisted in the absence of a dicarboximide spray programme. The incidence of benomyl resistance has not decreased since the last survey in 1984 in spite of a considerable reduction in the use of benzimidazole fungicides. There were no clear indications that the use of dichlofluanid influenced the incidence of benomyl or iprodione resistance. Disease control was poorer in crops with a higher incidence of iprodione resistance.     

Viruses of pepper in plastic houses in Crete

During a survey of virus diseases affecting pepper grown in plastic houses in Crete, during 1984–1986, tomato mosaic virus (ToMV) and tobacco mosaic virus (TMV) were detected. The most common virus was TMV, being present in samples of alle pepper cultivars carrying the L₁ resistance gene, while ToMV was isolated only from susceptible pepper cultivars. According to responses ofCapsicum spp. the isolates from 640 samples checked were classified into three pathotypes: P₀, P_1.2 and P_1.2.3. Results of this study show that P_1.2 represents at present the major threat to the Cretan pepper industry.Samenvatting Bij een in de jaren 1984–1986 gehouden inventarisatie van virusziekten in paprika in plastic-foliekassen op Kreta werd zowel het tabaksmozaïekvirus (TMV) als het tomatemozaïekvirus (ToMV) aangetoond. TMV kwam zeer algemeen voor: het werd aangetroffen in alle monsters van de paprikarassen met het resistentiegen L₁. ToMV werd alleen geïsoleerd uit planten van vatbare paprikarassen. Volgens de waargenomen symptomen die de isolaten van 640 monsters opCapsicum spp. vertoonden, konden de isolaten in drie pathotypen, nl. P₁, P_1,2 en P_1,2,3, worden geklassificeerd. Uit het onderzoek is gebleken dat P_1,2 de belangrijkste bedreiging vormt voor de teelt van paprika op Kreta.     

Viruses of tomato in plastic houses in Crete

Tomatoes grown in plastic houses in Crete have been inspected since 1980 for virus diseases. Plants with virus-like symptoms were checked by sap inoculation to test plants and the isolated viruses were identified by host reaction and serology. The most common viruses were, in order of frequency, tomato mosaic virus (ToMV), potato virus X, tomato bushy stunt virus (TBSV), potato virus Y and cucumber mosaic virus. The large use of ToMV-resistant cultivars reduces gradually the importance of ToMV while TBSV tends to become a serious problem of tomato in Crete.Samenvatting Van 1980–1984 werden op Kreta de in plasticfolie-kassen geteelde tomaten geïnventariseerd op de aanwezigheid van virussen. Verdachte plante werden door sapinoculatie op toetsplanten onderzocht. De daarbij geïsoleerde virussen werden daarna via de symptomen op de waardplanten en serologisch geïdentificeerd. In volgorde van belangrijkheid werden de volgende virussen het meest aangetroffen: tomatemozaïekvirus, aardappelvirus X, tomatedwerggroeivirus, aardappel Y virus en komkommermozaïekvirus, De laatste jaren is door de toenemende teelt van tomaterassen met resistentie tegen tomatemozaïekvirus het belang van dit virus sterk verminderd, terwijl het tomatedwerggroeivirus een steeds ernstiger probleem lijkt te worden.     

2013年我国黏虫发生特点分析

2013年黏虫维持了2012年以来的重发态势。二代黏虫在东北、华北、黄淮局部、江南局部、西南地区普遍发生,多种作物受害严重,总体发生程度重于2012年同期,山西、河北等局部地区大发生。三代黏虫在东北、华北和黄淮局部等地偏重发生,虽然发生面积、发生程度整体上不如2012年严重,但是仍显著重于常年,并且在辽宁、山西、山东的局部地区造成严重危害。分析提出,监测防控及时到位、关键时期气象条件不利,是2013年三代黏虫发生程度轻于2012年的主要原因。