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1.
对新疆阿勒泰地区27个主要菜地和果园的叶螨种类作了调查,共鉴定出6个种,分别隶属于3个属,其中土耳其斯坦叶螨(Tetranychusturkestani)是危害该区蔬菜和果树的优势种。另外,首次在新疆发现了绣球叶螨(Tetranychushydrangeae)。  相似文献   

2.
以玻片浸渍法检测河南和宁夏两地区朱砂叶螨(Tetranychus cinnabarinus)和截形叶螨T.truncatus对3种药剂的抗性。结果表明,河南的朱砂叶螨和截形叶螨对三氯杀螨醇、久效磷表现抗性;对氧化乐果仍处在敏感水平。宁夏的两种叶螨对3种药剂都表现敏感。同时,截形叶螨对3种药剂的LC50均高于朱砂叶螨。大田防治时应减少三氯杀螨醇的使用次数。截形叶螨为优势种时,禁止使用久效磷防治。提倡氧化乐果在防治棉花叶螨和兼治棉蚜时应用。  相似文献   

3.
研究了不同恒温条件下阿维菌素(Avermectin)对朱砂叶螨[Tetranychus cinnabarinus(Boisduval)]和二斑叶螨(T.urticae Koch)的致死作用,拟合了阿维菌素对两种叶螨的毒力与温度之间的关系。结果表明:阿维菌素分别在16、21、26、31℃和36℃的恒温条件下,对两种叶螨的毒力与温度呈正相关关系,即温度越高毒力越强;朱砂叶螨对阿维菌素的敏感性高于二斑叶螨。  相似文献   

4.
新乡棉花叶螨及优势种消长的初步调查   总被引:1,自引:0,他引:1       下载免费PDF全文
曹煜 《植物保护》1988,14(5):10-11
1986—1987年,用制作玻片标本和记录叶片上螨量的方法观察新乡棉区棉花叶螨优势种的消长。结果表明:一、新乡地区棉花叶螨为朱砂叶螨Tetranychus cinnabarinus和截形叶螨T.truncatus构成的复合种群。二、不同年份及同一年份不同时期优势种有变化。1986年朱砂叶螨是优势种,1987年棉花生长初期,朱砂叶螨为优势种,6月中旬后,该螨所占比例开始下降,7月上旬后,截形叶螨成为优势种,并维持优势到危害后期。  相似文献   

5.
加州新小绥螨对朱砂叶螨的控制作用   总被引:2,自引:2,他引:0  
为明确加州新小绥螨Neoseiulus californicus(McGregor)国内种群对朱砂叶螨Tetranychus cinnabarinus(Boisduval)的控制潜力,应用功能反应、数值反应及实验种群生命表参数评价了该捕食螨对朱砂叶螨的控制能力。加州新小绥螨对朱砂叶螨的功能反应能很好地拟合Holling Ⅱ方程。在25℃,加州新小绥螨雌成螨对朱砂叶螨卵、幼螨、若螨和成螨的功能反应参数a/Th值分别为42.4195、81.6275、54.3044和17.9399,对朱砂叶螨幼螨、若螨和卵的控制力高于成螨。在19~31℃,加州新小绥螨对朱砂叶螨雌成螨日均捕食量和对猎物的控制能力a/Th随温度升高而增大,在31℃时达最大值,分别为10.80头和29.5364。在28℃时,加州新小绥螨的净增殖率和内禀增长率分别为26.1522和0.2213。表明加州新小绥螨国内种群表现出重要的生物防治潜能。  相似文献   

6.
枣缩果病病原子实体的诱导和鉴定   总被引:9,自引:1,他引:9  
1992~1996年作者对枣缩果病病原研究认为该病由Coniothyriumsp.(.sp)、Alternariaalter-nataf.sp.tenuis和一种半知菌亚门有隔有色丝状菌等多病原引起。经室内外对上述病原菌的子实体诱导,以及越冬后自然病果上子实体的发现,病原菌C.sp.经再鉴定为C.olivaceumBon,另一病原菌半知菌亚门有隔有色丝状菌订名为群生小穴壳菌DothiorelagregariaSacc。至此明确引起枣缩果病的病原为C.olivaceum、Alternariaalternataf.sp.tenuis、Dothiorelagregaria和一种细菌(待鉴定)  相似文献   

7.
为揭示寒地水稻叶片SPAD值及其衍生值与稻米蛋白质含量的关系,于2020—2021年在水稻拔节期(T1)、孕穗期(T2)、齐穗期(T3)测定顶部3片叶的SPAD值,依据盆栽试验(试验1和试验2)的数据资料建立SPAD值衍生指标与稻米蛋白质含量之间的关系模型,利用大田试验(试验3)数据资料对建立的模型进行验证。结果表明,2020年氮肥试验中A8水平(氮素施用量362.07 kg·hm-2)稻米蛋白质含量较A1~A7水平(A1~A7氮素施用量分别为0、51.72、103.45、155.17、206.90、258.62、310.35 kg·hm-2)分别极显著增加34.55%、27.44%、26.39%、22.19%、18.07%、14.39%、12.23%,而A8水平食味值较A1~A7水平分别极显著降低8.10%、5.06%、4.99%、4.10%、3.45%、2.96%、2.28%,2021年蛋白质含量、食味值变化趋势与前者相同。两年品种试验6个品种稻米蛋白质含量比较中,C6品种(三江6号)蛋白质含量较C5(龙粳21)、C4(垦粳8号)、C3(龙稻203)、C2(松粳16)、C1(松粳22)分别极显著提高2.99%、12.23%、10.43%、5.04%、15.63%,C6食味值较C5、C4、C3、C2、C1分别极显著降低1.17%、12.09%、3.54%、2.89%、7.93%。品种差异及施氮量对不同生育时期水稻顶部3 片叶的SPAD值分布规律有较大影响,但水稻冠层叶片出现的两次“黑黄交替”现象不受品种的影响,其中单片叶的SPAD值受品种差异的影响,与蛋白质含量不存在相关性,借助指标SPAD(L1+L2+L3)/3、SPADL2×L3/mean可有效降低品种及环境差异对蛋白质含量预测结果的影响,指标SPAD(L1+L2+L3)/3与蛋白质含量在T1~T3期(拔节期、孕穗期、齐穗期)的拟合方程分别为:Y=0.24X-1.94 ,R2为0.75**Y=0.25X-1.69,R2为0.74**Y=0.27X-2.45 ,R2为0.72**;SPADL2×L3/mean拟合方程分别为:Y=0.22X-1.05 ,R2为0.75**Y=0.27X-2.43, R2为0.72**Y=0.26X-2.24,R2为0.72**Y为蛋白质含量,X为SPAD衍生值),拟合方程均达到极显著水平。稻米蛋白质含量和食味值评分变现为线性负相关,回归方程为Y=-4.21X+113.32(Y为食味值,X为蛋白质含量),拟合优度R2=0.93**,达到极显著水平。综上,借助指标SPAD(L1+L2+L3)/3和SPADL2×L3/mean能够实现快捷、无损和实时预测稻米蛋白质含量,在一定程度上判定出稻米蒸煮食味品质的优劣,达到按质收获以及对品质实时监测的要求,促进优质寒地水稻的可持续发展。  相似文献   

8.
地肤提取物杀螨活性的研究   总被引:19,自引:0,他引:19  
采用多种溶剂和方法对地肤全株进行了提取,测定了其中杀螨活性最高的氯仿提取物的多种溶剂萃取物对二斑叶螨(Tetranychus urticae Koch)和朱砂叶螨[Tetranychus cinnabarinus(Boisduval)]的生物活性。结果表明,氯仿提取物的生物活性显著高于石油醚和甲醇提取物,提取物的氯仿萃取物对2种螨的生物活性最强。本试验还对该种植物的杀螨活性有效成分进行了初步研究。氯仿萃取物经柱层分离得到流分112个,经薄层层析(TLC)检验后,相同成分者合并,最终得流分11个。生物活性测定结果表明,F9活性最高,其对二斑叶螨、朱砂叶螨和山楂叶螨的致死中浓度分别达到了0.390 3、0.298 1、0.256 8 mg /mL。  相似文献   

9.
选取关中平原冬小麦越冬后2002—2009年每年3—5月共9旬的条件植被温度指数(VTCI)遥感干旱监测结果,将冬小麦越冬后分为四个主要生育时期,分别运用因子权重排序法、熵值法及组合赋权法确定各生育时期干旱对产量的影 响权重,计算关中平原各市冬小麦每年的加权VTCI,并建立加权VTCI与冬小麦单产间的一元线性回归模型。结果表明,关中平原大部分地区的加权VTCI与小麦单产密切相关。其中,熵值法确定的加权VTCI与小麦单产的线性相关性不显著,渭南、咸阳及铜川的决定系数R2值均低于0.5;因子权重排序法和组合赋权法确定的加权VTCI与小麦单产的线性相关性显著,咸阳、宝鸡及西安的R2值接近或高于0.6,渭南接近 0.5,铜川较差。且组合赋权法的结果中宝鸡和西安的R2值接近0.7,优于因子权重排序法和熵值法的结果。  相似文献   

10.
临夏地区春蚕豆根腐病发生与为害调查   总被引:3,自引:1,他引:3  
对甘肃临夏地区的340块春蚕豆田根腐病的调查,明确了该区蚕豆根腐病死亡率为1%~90%,平均为15.33%;死亡率小于10%的地块占调查地块总数59.7%,大于30%地块占17.35%,随着海拔梯度的增高,蚕豆死亡率逐渐下降。病原真菌主要有腐皮镰刀菌(Fusariumsolani)、燕麦镰刀菌(F.ave-naceum)、粘帚霉(Gliocladiumroseum)和尖孢镰刀菌(F.oxysporum)  相似文献   

11.
以民勤不同年限(1、2、4、8、13 a)退耕地为研究对象,以当年耕地作为对照,采用时空替代法及通径分析法研究不同年限退耕地土壤理化性质、土壤酶活性变化特征及二者的相关关系.结果表明:(1)随着退耕年限的增加土壤速效钾含量表现为缓慢上升趋势,在退耕13 a达到峰值(411 mg·kg-1);其余理化指标均在退耕13 a...  相似文献   

12.
采用“轮作、休闲、连作、间作、休闲1年-种植”5种耕作模式,结合通径分析,研究不同耕作制度对胡麻土壤酶活性变化特征的影响,以及土壤养分对土壤酶的影响效应。结果表明:(1)胡麻枞形期,研究区表土层4种土壤酶活性各处理间无显著差异(P<0.05),说明不同耕作制度在胡麻生长前期对土壤酶影响不明显;盛花期,蔗糖酶活性T1、T2、T3和T4分别较T5提高44.6%、53.3%、61.9%和34.9%,脲酶活性T5、T1和T2分别较T4提高266.0%、157.0%和140.0%,碱性磷酸酶活性T3较T2提高54.0%;硕果期,过氧化氢酶活性T2 和T3分别为1.41 mL·g-1·h-1和1.51 mL·g-4·h-1,显著高于T1、T4和T5;(2)胡麻盛花期,亚土层土壤脲酶活性T2和T5分别为1.74 mg·g-1·d-1和1.70 mg·g-1·d-1,显著高于T1、T3和T4;过氧化氢酶活性T1较T5提高212.0%,碱性磷酸酶活性T5较T4提高了21.6%;(3)蔗糖酶与碱性磷酸酶间显著负相关,与脲酶间正相关,其余酶为负相关;(4)耕层不同土壤酶活性受土壤养分因子影响的多重效应不同,pH、全磷含量能够促进蔗糖酶、过氧化氢酶活性提高,有机质、pH含量促进碱性磷酸酶活性提高;亚土层不同土壤酶活性受土壤因子影响的多重效应增加,主要为限制因子,且限制因子数要远大于表土层。  相似文献   

13.
The action of deltamethrin on the calcium/calmodulin-dependent protein kinase (CaM-Kinase II) and phosphatase system in the rat brain synapse was studied under various experimental conditions to optimize these enzyme activities and to facilitate the studies of the mechanism of interaction of this pesticide with several components of this enzyme system. To obtain a clear-cut inhibition of this enzyme by deltamethrin the following conditions must be met: (a) the enzyme system should be purified by precipitation with ammonium sulfate (450 g litre?1) prior to the addition of deltamethrin, (b) both Ca2+ and calmodulin (CaM) should be added to the incubated media before the addition of [y-32P]ATP, (c) deltamethrin should be incubated at least 10 min (but less than 30 min) with the enzyme system before [y-32P]ATP addition, (d) the incubation temperature should be above 20°C (optimum 30°C), (e) [y-32P]ATP concentration should be in the order of 10? M (concentration adjusted using cold ATP), and (f) the incubation time with [y?P]ATP for incorporation of 32P into the protein should be in the neighborhood of 60 s. Under these conditions, the inhibitory potency of various active and inactive isomers or analogs of pyrethroids and DDT was tested. The order of the inhibitory power of these active forms of pesticides was 1 R-deltamethrin > (S)(RS) fenvalerate ≥ p,p′-DDT. Other compounds were not active at the concentration tested, indicating the differential sensitivity of this enzyme and the existence of a correlation of inhibitory power to insecticidal activity.  相似文献   

14.
Previously, we cloned a putative osmosensing histidine kinase gene (BcOS1) and revealed that a single amino acid substitution, isoleucine to serine at codon 365, conferred dicarboximide resistance in field isolates of Botrytis cinerea. This point mutation (type I) occurred within the restriction enzyme TaqI site of the wild-type BcOS1 gene. Thus, a procedure was developed for detecting the type I mutation of the BcOS1 gene using a polymerase chain reaction (PCR) in combination with restriction fragment-length polymorphism (RFLP). Diagnosis by PCR-RFLP was conducted on the 105 isolates isolated from 26 fields in Japan. All dicarboximide-sensitive isolates (49 isolates) had the wild-type BcOS1 gene, and the 43 isolates with the type I mutation were resistant to dicarboximides without exception. These data indicate that dicarboximide-resistant isolates with type I mutation are widespread throughout Japan. However, other types of dicarboximide resistance were detected among isolates from Osaka; among the 24 resistant isolates from Osaka, 12 had the BcOS1 gene without the type I mutation. BcOS1 gene sequencing of these resistant isolates classified them into two groups, type II and type III. The type II isolates have three amino acid substitutions within BcOS1p (368Val to Phe, 369Gln to His, and 447Thr to Ser). The type III isolates have two amino acid substitutions within BcOS1p (369Gln to Pro and 373Asn to Ser). These amino acid changes are located on the amino acid repeat domain in BcOS1p. The three types of resistant isolates were all moderately resistant to dicarboximides without significant osmotic sensitivity, and their pathogenicity on cucumber leaves was also very similar to that of the wild-type isolate.  相似文献   

15.
为进一步完善全膜双垄沟播玉米栽培技术体系,采用大田随机区组试验法,研究了不同施肥水平下全膜双垄沟播玉米土壤酶活性及氮磷养分含量的动态变化情况。结果表明:在玉米生长前期,土壤脲酶、碱性磷酸酶、蔗糖酶活性以及碱解氮、速效磷含量均呈现快速增长趋势。脲酶、蔗糖酶、过氧化氢酶活性和碱解氮含量均在拔节期达到最大值,碱性磷酸酶活性和速效磷含量在抽雄期达到最大值。在玉米生长后期,各种土壤酶活性和氮磷养分含量又呈降低趋势。土壤脲酶活性与氮磷养分含量,土壤碱性磷酸酶活性与速效磷含量均存在显著或极显著正相关关系,土壤蔗糖酶活性与氮磷养分含量也存在显著的正相关关系,而土壤过氧化氢酶活性与氮磷养分含量之间,土壤碱性磷酸酶活性与碱解氮之间无显著相关关系。西北干旱半干旱地区全膜双垄沟播玉米种植密度确定为6.75×104株·hm-2时,最佳施肥量为纯N 210 kg·hm-2、P2O5168 kg·hm-2。  相似文献   

16.
连作对谷子土壤酶活性及养分的影响   总被引:6,自引:0,他引:6  
为探明谷子连作对土壤环境的影响,分析不同连作年限对谷子土壤养分和酶活性的影响,本研究在4a不施肥定位试验的基础上,设置连作2 a(T1)、连作3 a(T2)、连作4 a(T3)和轮作(CK)4个处理,分别测定了土壤养分、土壤脲酶、碱性磷酸酶、蔗糖酶和过氧化氢酶活性及其变化。试验结果表明,与轮作(CK)相比,连作2 a(T1)、连作3 a(T2)和连作4 a(T3)分别减产6.9%、12.7%和35.6%,随着连作年限增加,减产幅度加大;连作土壤氮、磷含量降低,其中速效氮含量降低最为显著(P0.05),速效钾含量变化不显著(P0.05),土壤p H升高。连作条件下,土壤脲酶、碱性磷酸酶、蔗糖酶和过氧化氢酶活性均呈现逐年降低的趋势,且随着连作年限增加,降低越显著,连作4 a(T3)显著低于其它处理(P0.05)。  相似文献   

17.
生物菌肥和钾肥配施对苹果钾素吸收及果实品质的影响   总被引:1,自引:0,他引:1  
为了研究生物菌肥和钾肥对苹果果实品质及生长发育的协同作用,以7 a生‘瓦里短枝’(Vallee spur Del)为研究对象,设置T1(K_2O 420 kg·hm~(-2))、T2(生物菌肥2 520 kg·hm~(-2))、T3(生物菌肥2 520 kg·hm~(-2)+K_2O 294 kg·hm~(-2))、T4(生物菌肥2 520 kg·hm~(-2)+K_2O 420 kg·hm~(-2))、T5(生物菌肥2 520 kg·hm~(-2)+K_2O 546 kg·hm~(-2))和CK(不施肥)6个处理,研究了不同施肥处理对苹果钾素吸收、土壤酶活性、根际微生物数量及果实品质的影响。结果表明:(1)与T1相比,T3、T4及T5显著提高了果园钾肥农学效率、钾肥贡献率和钾肥偏生产力(P0.05),但T4和T5差异不显著。(2)各处理不同器官中钾素累积量大小顺序依次为T5T4T3T1T2CK,T4和T5差异不显著,但均显著高于其它处理(P0.05)。(3)生物菌肥和钾肥配施后显著提高了土壤蔗糖酶、多酚氧化酶、碱性磷酸酶、脲酶活性和根际土壤细菌、放线菌及真菌的数量(P0.05),但T3、T4及T5之间差异不显著(P0.05)。(4)配施后显著提高了0~120 cm土层内根系活力(P0.05),显著提高了果实的平均单果重、可溶性固形物含量、Vc含量及果实硬度(P0.05),但T4和T5差异不显著(P0.05)。(5)果实单果重、可溶性固形物含量及Vc含量均与土壤微生物数量和土壤酶活性呈显著正相关。综上,生物菌肥2 520 kg·hm~(-2)+K_2O 420 kg·hm~(-2)是试验区合理的施肥量,能有效提高钾肥利用效率,提高土壤肥力和改善果实品质。  相似文献   

18.
分别以4株苦豆子内生真菌菌液浓缩物为诱导子,研究不同诱导时间下,各诱导子对苦豆子组培苗中氧化苦参碱(OMA)含量以及防御酶苯丙氨酸解氨酶(PAL)、过氧化物酶(POD)、抗坏血酸过氧化物酶(APX)和过氧化氢酶(CAT)活性的影响。结果显示:4种苦豆子内生真菌的菌液浓缩物均可提高宿主中OMA的积累,其中诱导效果最佳的是内生真菌诱导子XKYKDF40,在0~15 d诱导期间宿主中OMA含量持续增长且始终高于对照,在诱导第15 d达到最高,为3.616 mg·g-1,是同时期对照组的2.09倍。4种内生真菌诱导子还可诱发宿主中生物碱合成关键酶PAL和3种抗氧化酶(POD、APX和CAT)活性升高。诱导子XKYKDF40激发PAL活性的作用最佳,在诱导第6 d PAL活性达最大值,为61.92 U·g-1,是同时期对照组的1.42倍;与其他诱导子相比,诱导子XKZKDF27能够明显诱发POD的活性,在诱导第12 d达到最大值,为62.30 U·mg-1,是同时期对照组的2.70倍;诱导子XKZKDF11可诱导宿主中的APX和CAT活性大幅度提高,在诱导第12 d酶活性达到最高,分别为0.5538 U·mg-1和19.82 U·mg-1,是同时期对照组的4.97倍和3.00倍。结果表明,苦豆子内生真菌诱导子的加入不仅激活了宿主组培苗的防御性应答反应,还促进了OMA的合成。  相似文献   

19.
Summary. The metabolism of monuron in excised leaves of bean (Phaseolus vulgaris L., var. Black Valentine) and corn (Zea mays L., var. Batam Cross) were studied with carbonyl-14C-labelled monuron. The metabolic conversions of monuron in both plant species were exponential and followed first order reaction kinetics. The metabolism of monuron can be divided into two major pathways: demethylation and hydroxylation. At a monuron concentration of 16 ppm the hydroxylation was dominant in the bean leaves. As the concentration of monuron was increased the participation of the hydroxylation pathway became less probably due to the inhibition of enzymes involved by monuron. The demethylation pathway was not affected by higher monuron concentration. In the corn leaf, however, sequential demethylation was always the major pathway of monuron transformation and there was no inhibitory effect observed on either pathways as the concentration of monuron increased. The following radioactive metabolites were found in the alcohol extract of bean and com leaves receiving carbonyl-14C-labelled monuron: N′-(4-chlorophenyl)-N-methylurea, p-chlorophenylurea, two polypeptide complexes of monuron, one polypeptide complex of N′-(4-chlorophenyl)-N-methylurea and β-D-glucosides of N-(2-hydroxy-4-chlorophenyl) urea, N′-(2-hydroxy-4-chlorophenyl) N-methylurea, and N′-(2-hydroxy-4-chlorophenyl)-N,N-dimethylurea. In addition, one minor radioactive peak was found only in the alcohol extract of corn leaves, which yielded four unidentified radioactive metabolites after acid or enzyme hydrolysis with β-glucosidase. Métabolisme du monuron dans des feuilles excisés de maïs et de haricot  相似文献   

20.
A single dose (4 mg kg?1) of 14 C-labelled (R)-flamprop-methyl to rat was rapidly metabolised and 90% of the dose was eliminated in urine and faeces within 48 h. Four days after dosing, tissue residues were 0–1 μg equivalents g?1 tissue or much less, with the exception of kidney (0–22 μg g?1). There was a statistically significant sex difference in the routes of elimination; this may be attributed to differences in the biliary elimination of the major metabolite, flamprop acid, or its glucuronide conjugate. The fate of racemic flamprop-methyl was very similar to that of the (R)-isomer. The major metabolic routes were hydrolysis of the esters to the corresponding acids, hydroxylation of the benzoyl aromatic rings and conjugation. The flamprop acid derived from the (R)-flamprop-methyl was found to be partially converted to the (S)-form (R:S ratio, 87:13). This reaction is discussed in the context of other such biological racemisations recently reported.  相似文献   

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