毛葡萄穗轴溃疡病病原鉴定及其防治药剂初步筛选

马铃薯黑痣病立枯丝核菌(Rhizoctonia solani)菌丝存在遗传分化现象.从定西市马铃薯产区采集茎部和薯块病样80份进行融合群测定.结果表明,80株菌株中与标准菌株AG3融合的占总数的70.0％、与AG4-HG-Ⅱ融合的占15.0％、与AG2-1融合的占7.5％.为了有效控制马铃薯黑痣病,采用生长速率法在室内选取9种杀菌剂进行药效评价.结果表明:30％噻呋酰胺悬浮剂EC50最低,为0.015 2μg/mL;其次是40％氟胺·异菌脲悬浮剂、3％多抗霉素可湿性粉剂和250 g/L嘧菌酯悬浮剂,其EC50分别为0.064 1、0.129 3和0.176 7μg/mL;EC50最大的是25.75％多抗·福美双可湿性粉剂,为2.930 4μg/mL.田间拌种,30％噻呋酰胺悬浮剂和250 g/L嘧菌酯悬浮剂防效较好,达70％以上,值得在生产中推广.     

噻呋酰胺与嘧菌酯混配对马铃薯黑痣病菌增效作用及其田间防效

为明确噻呋酰胺与嘧菌酯混配对马铃薯黑痣病菌Rhizoctonia solani的增效作用及对马铃薯黑痣病的田间防效,采用菌丝生长速率法和田间药效试验测定二者混配组合对其的联合毒力,分别用Wadley法和Abbott法评价混配组合的增效作用,并比较拌种、沟施及苗期茎基部喷淋3种施药方式对黑痣病的田间防效。结果表明,噻呋酰胺与嘧菌酯以质量比3∶1、2∶1、1∶1和1∶2进行混配时抑制马铃薯黑痣病菌菌丝生长的增效系数分别为1.7、2.7、2.5和1.9,其中2∶1和1∶1的混配组合增效作用较为明显。240 g/L噻呋酰胺悬浮剂与250 g/L嘧菌酯悬浮剂1∶1桶混以240 g(a.i.)/hm~2沟施对马铃薯黑痣病的防效优于拌种和苗期茎基部喷淋的防效,沟施方式下对植株黑痣病的防效为65.3%,对薯块黑痣病的防效为71.6%,增效系数为1.1,表现增效作用。表明噻呋酰胺与嘧菌酯有效成分质量比1∶1的混配组合以240 g(a.i.)/hm~2为推荐剂量沟施可有效防治马铃薯黑痣病。     

马铃薯炭疽病发生情况及室内药剂筛选

近年来,在甘肃省定西市马铃薯产区发现一种新病害:马铃薯炭疽病。2009-2011年7-10月,对不同品种、不同栽培措施以及不同土壤类型的马铃薯种植地块炭疽病发生情况进行了调查,定西市马铃薯炭疽病平均发病率高达12.6%,‘黑美人’、‘克新1号’和‘新大坪’发病率都高于50%,其中,地膜栽培发病率高于露地,沙质土壤高于黏土。为了有效控制炭疽病,本研究在室内选取7种杀菌剂,采用生长速率法进行药效评价。结果表明:75%肟菌.戊唑醇可湿性粉剂、250g/L嘧菌酯悬浮剂、25%溴菌腈可湿性粉剂3种杀菌剂的EC50较低,分别为5.039 3、5.448 3g/mL和5.538 6g/mL;其次是23%络氨铜水剂、80%百菌清可湿性粉剂、10%苯醚甲环唑水分散粒剂,EC50分别为6.082 8、6.300 8、6.884 9g/mL;EC50最大的是70%丙森锌可湿性粉剂,其值为9.200 3g/mL。     

4种常用杀菌剂对江苏省番茄枯萎病菌的毒力

采用菌丝生长速率法测定了4种杀菌剂对36株番茄枯萎病菌(Fusarium oxysporum)的毒力。结果表明,不同杀菌剂对番茄枯萎病菌的毒力水平有显著差异,25%氰烯菌酯悬浮剂和50%多菌灵可湿性粉剂对菌落生长的抑制毒力最强,EC50分别为1.65μg/mL和2.91μg/mL;3%中生菌素可湿性粉剂的毒力次之,EC50为12.56μg/mL;75%百菌清可湿性粉剂的毒力最小。不同地区的番茄枯萎病菌对4种杀菌剂的敏感性存在明显的差异,铜山地区的菌株除了对多菌灵、氰烯菌酯有较高的敏感性外,对其他2种杀菌剂都呈不同程度耐药性;沭阳地区的菌株对4种杀菌剂的敏感性均很强;姜堰地区的菌株对百菌清有较弱的敏感性,对其他3种杀菌剂的敏感性均较强。本研究为化学防治番茄枯萎病、科学合理用药提供参考依据。     

6种杀菌剂对马铃薯黑痣病菌的毒力和拌种防效

为了探索马铃薯黑痣病高效防控技术,本研究选择240 g/L噻呋酰胺SC、20％嘧菌酯WG、10％苯醚甲环唑ME、0.3％四霉素AS、100万孢子/g寡雄腐霉WP、1％申嗪霉素SC等6种杀菌剂进行室内毒力测定和田间拌种防效试验.结果显示,6种杀菌剂对马铃薯黑痣病菌均有抑菌作用,其中1％申嗪霉素SC、20％嘧菌酯WG、0....     

水稻纹枯病防治药剂筛选试验研究

噻呋酰胺240k/L悬浮剂13mL/667m2、嘧茵酯250k/L悬浮剂40mL/667m2对水稻纹枯病病指防效分别为98.4％、97.0％,显著优于其它各药剂防效;丙环唑25％乳油45mL/667m2、己唑醇50％水分散粒剂l0g/667m2病指防效分别为88.1％、84.9％;井冈霉素5％水剂200mL/667m2、咪鲜胺25％乳油80mL/667m2防效最差,分别为44.4％、37.0％.因此,噻呋酰胺、嘧菌酯对水稻纹枯病具有良好的预防及治疗效果,且对水稻生长安全,水稻纹枯病重发年份首选使用;丙环唑、己唑醇是取代井冈霉素的优良药剂,生产上可加以推广.     

不同药剂对马铃薯晚疫病的防治效果

试验研究了68.75%氟菌.霜霉威悬浮剂、69%烯酰.锰锌可湿性粉剂、52.5%噁酮.霜脲氰水分散粒剂等8种药剂对马铃薯晚疫病的防治作用,通过差异显著性分析及灰色关联度分析得知:52.5%噁酮.霜脲氰水分散粒剂对马铃薯晚疫病的防治效果最佳,其他依次为69%烯酰.锰锌可湿性粉剂、72%霜脲.锰锌可湿性粉剂、68.75%氟菌.霜霉威悬浮剂、70%丙森锌可湿性粉剂、250g/L嘧菌酯悬浮剂、25%甲霜灵.霜脲氰可湿性粉剂、25%丁吡吗啉悬浮剂。     

引起山西省玉米纹枯病的主要丝核菌融合群对3种杀菌剂的敏感性

为明确引起山西省玉米纹枯病的主要丝核菌融合群对氟酰胺、噻呋酰胺和戊菌隆3种杀菌剂的敏感性,采用菌丝生长速率法测定了氟酰胺、噻呋酰胺和戊菌隆对268株丝核菌菌丝生长的EC50值,建立敏感基线并分析了噻呋酰胺和其他杀菌剂对病菌活性的相关性。结果表明：立枯丝核菌Rizoctonia solani融合群AG-5和玉蜀黍丝核菌R. zeae融合群WAG-Z对噻呋酰胺最为敏感,对氟酰胺敏感性次之,对戊菌隆敏感性最差;立枯丝核菌融合亚群AG-1-IA则对戊菌隆最为敏感,对噻呋酰胺次之,对氟酰胺最差。通过箱形图分析剔除异常的EC50值后,融合群AG-5和WAG-Z对氟酰胺、噻呋酰胺和戊菌隆的敏感性频率均呈连续的单峰曲线分布,符合正态分布。因此,将EC50均值0.165、0.048和2.500μg/mL分别作为融合群AG-5对氟酰胺、噻呋酰胺和戊菌隆的敏感基线;将0.518、0.106和1.616μg/mL分别作为融合群WAG-Z对氟酰胺、噻呋酰胺和戊菌隆的敏感基线。噻呋酰胺与氟酰胺、戊菌隆、己唑醇或咯菌腈对融合群AG-5和WAG-Z的抑制活性不存在相关性。研究结果可为山西省玉米纹枯病杀菌剂施用策略的制...     

25%嘧菌酯悬浮剂防治马铃薯早疫病田间药效试验

25%嘧菌酯悬浮剂对马铃薯早疫病具有较好的防治效果。使用25%嘧菌酯悬浮剂(阿米西达)商品量18～36g/667m2,2次药后防效可达81.11%～84.75%,显著优于80%代森锰锌可湿性粉剂100g/667m2的防效。     

几种杀菌剂对玉米顶腐病菌的抑制作用

用平板菌落法测定了杀菌剂对玉米顶腐病菌菌丝生长、产孢、孢子萌发及芽管伸长的抑制作用。结果表明:浓度为1000μg/mL的60%氟吗·锰锌可湿性粉剂、15%三唑酮可湿性粉剂、47%腈菌·锰锌可湿性粉剂3种杀菌剂对菌丝生长抑制率为100%。1000μg/mL和500μg/mL供试各杀菌剂能抑制分生孢子萌发,50%多菌灵可湿性粉剂和77%氢氧化铜可湿性粉剂抑制孢子萌发EC50分别为0.2719μg/mL和762.8854μg/mL。供试杀菌剂抑制芽管伸长的EC50差异显著,47%腈菌·锰锌可湿性粉剂EC50为0.1268μg/mL,70%甲基硫菌灵可湿性粉剂EC50为383.9653μg/mL。杀菌剂对分生孢子产生抑制作用显著,产孢量显著小于对照,60%氟吗·锰锌可湿性粉剂能完全抑制孢子形成。     

灰翅麦茎蜂对不同品种春小麦穗粒重的影响

在青海省湟水流域民和、西宁、大通３地田间播种１２个春小麦品种以测定灰翅麦茎蜂幼虫蛀茎危害对各品种单株穗粒重性状的影响。结果表明，各供试春小麦品种被害单株穗粒重显著下降，损失率为９．４％～３７．３％。辐阿１号损失率低，显示一定的耐虫性。     

2000—2010 年全国森林生物灾害发生、损失与趋势分析

导致我国森林资源受损的主要生物灾害为森林病害、虫害与鼠害等。基于2000-2010年全国森林病虫鼠害的发生面积、程度等数据,计算获得森林蓄积、直接经济与生态服务功能价值的灾害损失量,采用多元线性回归法等分析我国森林生物灾害发生、灾害损失的特点与趋势。结果表明：我国森林生物灾害发生范围（区域）2010年较2000年增加0.61%,发生面积从2000年的8.52×106公顷次增加到2010年的1.16×107公顷次,增长36.7%,上升趋势显著,对其贡献大小依次为：虫害（贡献率54.2%）＞鼠害（贡献率33.3%）＞病害（贡献率12.5%）。森林病害、虫害、鼠害发生面积均呈显著上升趋势,尤其是鼠害发生面积2010年较2000年增长105.18%。但是,从发生程度上看,森林生物灾害新增面积以轻度发生为主,其对病虫鼠害、病害、虫害、鼠害面积呈增加趋势的贡献率分别为75%、67.4%、72.8%、54.1%。伴随森林生物灾害面积增加,森林蓄积、生态服务价值损失呈显著上升趋势,如2010年蓄积损失2.48×107 m3、生态服务价值损失895.37亿元,分别较2000年增长5.2%与28.5%,而森林鼠害加重则是导致生态服务价值损失的重要因子。以上结果说明,近10多年来,我国森林生物灾害范围、发生面积显著扩增,尽管扩增面积多以轻度发生为主,但所导致的森林资源损失与发展趋势不容乐观。     

Population dynamics of Apodemus agrarius Pallas and its economic threshold in the paddy region

Abstract

Investigations were conducted in the double or middle season paddy regions from 1988 to 1990; main results showed that the population of Apodemus agrarius reached maximal reproductive rate between April and May, and between September and October each year. Their maximal population size occurred in July and between October and November each year. At different stages of the rice, mouse density (X) was significantly related to loss rate of the rice (Y). Studies on imitation mouse damage on rice indicated that the rice, damaged by the mice in tillering stage, possessed a certain capacity for compensation. When the mouse damage rate approached yield loss rate in the booting or spiked stage the rice plant lost this compensatory capacity. It will be seen from the above that early spring is the most available, feasible time for mice control. Under the current production level the economic thresholds of mouse density are 3% in spring, 5% for early and middle‐season rice and 7% for later rice.     

紫茎泽兰对棉花生长的影响及经济阈值

为明确紫茎泽兰Eupatorium adenophorum Spreng在棉田中的经济危害允许水平和经济阈值,采用添加系列试验和模型拟合的方法,在田间条件下研究紫茎泽兰不同密度对棉花的生长性状及产量的影响.在紫茎泽兰的竞争干扰下,棉花果枝数和单株铃数均随着紫茎泽兰密度的增加而逐渐降低.当紫茎泽兰密度达到60株/m2时,棉花果枝数和单株铃数较无紫茎泽兰对照分别减少了22.1％和57.2％,同时棉花皮棉产量损失率也达到57.2％.棉田田间透光率也随紫茎泽兰密度的增加而降低,当紫茎泽兰密度为60株/m2时,其透光率仅为3.5％.幂函数模型y=3.049x1.031能较好地拟合紫茎泽兰密度(x)与棉花产量损失率(y)间的关系.棉田采用人工除草和41％草甘膦异丙胺盐水剂对紫茎泽兰进行防除时,紫茎泽兰的经济危害允许水平分别为8.42％、1.06％,经济阈值则分别为2.68、0.36株/m2.     

南方水稻黑条矮缩病对水稻产量损失及测报因子的初步研究

南方水稻黑条矮缩病是近年来在我国南方稻区新发生的一种重要病毒性病害.本文通过测定水稻品种‘T优272'上该病不同发病程度所对应的产量损失,分别建立了以病丛率、病株率与产量损失率之间的线性回归方程y=1.0270x1-1.363 4(R=0.999 6)、y=1.050 9x2-0.450 8(R=0.999 2).依据回归方程及南方稻区水稻生产实际情况,南方水稻黑条矮缩病在中稻上经济允许水平与成灾水平因子是病丛率4.79％与30.54％或病株率3.81％与28.98％,晚稻上经济允许水平与成灾水平因子分别是病丛率5.06％与30.54％或病株率4.08％与28.98％,中晚稻的绝收水平因子是病丛率79.22％或病株率76.55％.     

山东发现草地贪夜蛾为害马铃薯

重大迁飞性害虫草地贪夜蛾Spodoptera frugiperda(J.E.Smith)侵入我国后,截至2019年9月17日,已经在全国25个省份查见。2019年9月,山东省滕州市姜屯镇秋马铃薯地块发现疑似该虫为害,经鉴定,确认为草地贪夜蛾,对被害地块情况、马铃薯被害状、被害率进行了调查及描述,为该虫在马铃薯上的防治提供参考。     

叶螨为害苹果树的产量损失估测

1987—1989年研究苹果全爪螨(Panonychus ulmi)与山楂叶螨(Tetranychus viennenses)为害对苹果产量的影响。结果表明:①叶螨为害后,叶片的各项生理指标皆有反应,其中以光合作用强度最敏感;②叶螨为害对果实质量无显著影响,但不同螨量的果实体积之间存在明显差异;③平均累积雌成螨螨日(MDi)与平均减产率(Qi)之间有正相关关系,为害当年表现出果实变小单果重减轻,次年表现出花量减少,果实数下降。1987与1989年以苹果全爪螨为主,减产率分别为3.31%—11.25%与2.89%—10.75%。1988年以山楂叶螨为主,减产率为2.36%—13.48%;④上年受害树次年继续测产,看出叶螨的持续影响更为严重。以苹果全爪螨为主的持续减产率第二年达2.0%—86.2%;第三年的影响又相对减轻。以山楂叶螨为主的减产率第二年为-14.4%—69.4%。     

Comparative seed predation of woolly cupgrass (Eriochloa villosa) and yellow foxtail (Setaria pumila) along a field border in Canada

The seed predation of woolly cupgrass (Eriochloa villosa), an invasive weed of East‐Asian origin, was compared to that of yellow foxtail (Setaria pumila), an established and widespread weed, along a field border in Canada. The seeds of both species were glued to sandpaper cards and their removal in field conditions was recorded from July to September during the 3 years of 2009, 2010 and 2011. Predator exclusion cages allowed the evaluation of seed loss to be attributed to invertebrates, vertebrates and total seed loss due to predation for both species. Pitfall traps were installed and collected once in 2010 and during all the seed sampling dates in 2011 in order to evaluate predatory pressure from ground beetles and crickets. The average amount of seed loss that could be attributed to invertebrates was higher for S. pumila than for E. villosa, while the amount of seed loss that could be attributed to vertebrates was higher for E. villosa than for S. pumila in 2009 and 2010. The level of S. pumila seed loss to invertebrates was correlated with the sum of crickets (Gryllus pennsylvanicus) and beetles (Harpalus spp. and Ophonus rufibarbis) trapped during the 2011 season. During the same period, correlations between E. villosa seed loss to invertebrates and trapped insects were not observed. Reduced postdispersal seed predation by invertebrates could increase the local fall survival of the unburied seeds of invasive E. villosa populations, compared to other naturalized, smaller‐seeded weedy grasses.     

赣北二化螟卵寄生蜂寄生率动态及其对景观结构的响应

为探索南方稻区二化螟卵寄生蜂生防功能、评估卵寄生蜂在田间寄生动态并探讨对不同景观结构的响应,本文采用对比盆栽稻株叶片载卵、离体新鲜稻叶载卵和滤纸卵卡比对二化螟卵寄生蜂寄生率差异;利用盆栽稻株叶片载卵调查卵寄生蜂在稻田中的寄生率季节动态变化;在5月初、7月初和9月初分别调查了在不同景观样点二化螟卵寄生蜂寄生率,对不同空间尺度下（0.2,0.5,1.0,1.5,2.0 km）景观变量与卵寄生率进行模型分析,评估不同景观变量对卵寄生率的影响。结果表明,三种诱集方法差异显著,盆栽稻株叶片载二化螟卵被寄生的比率最高,其次为离体新鲜稻叶,滤纸卵卡效果最差。田间寄生动态调查表明,早稻卵被寄生比率偏低,中稻寄生率较高,在7月中旬二化螟卵被寄生率达到高峰（66.7%）,8月下旬以后,晚稻寄生率逐步下降。对不同空间尺度下景观结构变量与卵寄生率分析表明,1.5 km尺度下的林地与二化螟卵寄生蜂有着密切关系。低于40%林地面积比例时,二化螟卵寄生蜂寄生率随林地面积增加而降低;而在高于40%林地面积比例时,二化螟卵寄生率随林地面积增加而增加。综上所述,对于中国南方的小规模稻田景观,林地比例与二化螟卵寄生率有关,但相关效应并非单一地增加或减少的线性响应。研究结果可为南方稻区二化螟卵寄生蜂提供简便、有效的评估方法,并为综合利用二化螟卵寄生蜂控害功能,发展二化螟生防策略提供参考依据。     

Weed control in irrigated corn by hairy vetch interseeded at different rates and times

In order to study the potential of interseeded hairy vetch as a living mulch to control weeds in corn, a field study was conducted at the Agricultural Research Farm, Razi University, Kermanshah, Iran. The experiment was carried out in a split-split plot arrangement with four replications. The main plots were two weed treatments (weedy and weed-free for all of the growing season), the subplots were two hairy vetch planting dates (simultaneous with corn planting and 10 days after corn emergence), and the sub-subplots were three hairy vetch planting rates (0, 25, and 50 kg ha⁻¹). The results indicated that the weedy condition for all of the growing season reduced corn plant traits, including the seed yield, number of ears per plant, number of seeds per ear, 100-seed weight, height, Leaf Area Index, and leaf chlorophyll content, as compared to the weed-free condition for the entire growing season. The hairy vetch dry weight also was reduced by the full-season weedy condition. The traits under study were not significantly influenced by the hairy vetch planting times, but increasing the hairy vetch planting rate from 0 to 50 kg ha⁻¹ improved the corn yield, number of seeds per ear, 100-seed weight, height, Leaf Area Index, and leaf chlorophyll content. However, the number of ears per plant was not significantly influenced and the weed dry weight was reduced by half. Overall, from the standpoint of corn seed production, an interseeding amount of 25 kg ha⁻¹ of hairy vetch is recommended; taking into consideration the legume forage yield, an interseeding amount of 50 kg ha⁻¹ of hairy vetch is more beneficial.