不同药剂及施药技术对玉米南方锈病的防效研究

近年来, 由多堆柄锈菌Puccinia polysora Underw.引起的玉米南方锈病在黄淮海玉米产区发生频率高、危害重。为明确玉米南方锈病的最佳防治时期, 不同杀菌剂种类、施用剂量及防治次数对玉米南方锈病的防治效果, 在大田条件下, 以丙硫菌唑为供试杀菌剂, 探讨了在玉米不同生育期防治及防治次数对玉米南方锈病的防效及对玉米产量的影响, 同时研究了丙环唑、戊唑醇、氟环唑和丙硫菌唑4种杀菌剂不同使用剂量对玉米南方锈病的防效及对玉米产量的影响。结果表明, 分别在玉米大喇叭口期、抽雄初期、吐丝期和灌浆期防治, 以抽雄初期的防效最好(58.47%), 挽回产量损失率最高(108.05%)。施药两次对玉米南方锈病的防治效果显著优于施药一次的防治效果。丙环唑、戊唑醇、氟环唑和丙硫菌唑4种杀菌剂对玉米南方锈病均有一定的防控效果, 施药后14 d的防效均在85%以上, 施药后28 d的防效呈明显下降趋势。4种杀菌剂防治玉米南方锈病, 防效以氟环唑(1 350 mL/hm2)和丙硫菌唑(1 350 mL/hm2)最好, 施药后14 d的防效分别为95.68%和95.57%;施药后28 d的防效分别为55.39%和60.27%。4种杀菌剂不同使用剂量的挽回产量损失率均在70%以上。从防治效果及挽回产量损失率等方面综合考虑, 防治该病的最佳施药期为玉米抽雄初期, 4种供试药剂均可在大田防治中推广应用。     

闽南山区鲜食玉米叶斑病季节性流行动态及药剂防治

2018年和2019年,在田间条件下采用目测法系统调查研究了福建省南部山区鲜食玉米小斑病、大斑病和南方锈病3种重要叶斑病的季节性流行动态, 测定了不同玉米品种的病情严重度及几种杀菌剂对病害的防治效果。结果表明, 在试验调查的4个玉米种植季节, 3种叶斑病的病情指数随种植时间均呈“S”型曲线, 至乳熟期(R3)病情指数达到最大值, 大喇叭口期(V12)至籽粒建成期(R2)是病情快速发展的关键时期, 但不同年份、不同季节3种病害的时空流行趋势、植株不同叶位病级分布规律及其最终病情各不相同。当玉米生育期平均温度高于23.0 ℃时, 有利于小斑病和南方锈病的发生, 而平均温度低于23.0 ℃条件下则有利于大斑病的流行。供试的20个玉米品种对不同病害表现的抗性差异较大, 其中对小斑病、大斑病和南方锈病表现为中感和感病的品种合计分别占65.0%、55.0%和25.0%。此外, 从12种杀菌剂处理中, 筛选出430 g/L戊唑醇悬浮剂、400 g/L氟硅唑乳油、250 g/L吡唑醚菌酯乳油、30%肟菌·戊唑醇悬浮剂、吡唑醚菌酯+戊唑醇混剂(商品剂量5∶8)对小斑病、大斑病和南方锈病的防治效果较好, 防效分别达70.0%、82.0%和85.0%以上。上述研究结果可为福建省鲜食玉米叶斑病的预测预报及合理防控提供科学依据。     

6种药剂对玉米南方锈病田间防效评价

玉米南方锈病是豫南玉米生产上毁灭性的病害,近年来发生频繁,危害严重,缺乏药剂防治是该病害严重的主要原因之一。为明确表态杀菌剂对玉米南方锈病的防治效果,笔者选用戊唑醇,己唑醇,丙环唑,苯甲·丙环唑,醚菌酯,吡唑醚菌酯等6中不同杀菌剂对玉米南方锈病进行田间药效试验,结果表明6种杀菌剂对南方玉米锈病具有良好的控制作用,防治效果达到75%以上,增产效果显著,并对玉米生产安全,可以在大田生产中推广应用。     

苯醚甲环唑和丙环唑对黄淮海夏玉米区主要叶斑病的防治效果

为有效控制玉米后期叶斑病,本研究通过人工接种和自然发病两种方式,针对玉米小斑病、南方锈病和弯孢叶斑病进行了叶斑病防治技术的研究。结果表明,选用10%苯醚甲环唑WG和45%丙环唑ME,在玉米大喇叭口期采用机械喷雾的方式施药1次,对玉米小斑病、南方锈病和弯孢叶斑病都具有一定的防治作用,其中10%苯醚甲环唑WG对小斑病的最高防效为63.83%,挽回产量14.52%。两种药剂对弯孢叶斑病的最高防效都在60%以上,挽回产量最高达11%,但对南方锈病的防治效果并不理想,最高为29.91%。     

氯虫苯甲酰胺200g/L悬浮剂防治玉米螟药效试验研究

为了解决当前玉米螟危害严重的问题,笔者以常用药剂甲维盐2%乳油为对照药剂,在田间玉米上进行了氯虫苯甲酰胺200g/L悬浮剂不同使用剂量对玉米螟的防治效果和玉米增产效果的测试研究。结果表明:较对照药剂甲维盐2%乳油50mL/667m2高5.21%~24.37%;氯虫苯甲酰胺200g/L悬浮剂25mL/667m2和氯虫苯甲酰胺200g/L悬浮剂10mL+10mL/667m22次用药对玉米螟的防效最好、增产最明显。     

2021年黄淮地区夏玉米南方锈病流行因素分析及防控对策

黄淮地区是我国夏玉米重要产区, 近年来由多堆柄锈菌Puccinia polysora Underw.引起的玉米南方锈病的发生与流行已成为黄淮地区玉米产量的主要限制因素, 2021年玉米南方锈病在我国黄淮玉米产区大面积暴发流行, 危害损失之严重历年罕见?本文介绍了2021年度黄淮地区玉米南方锈病的发生危害情况, 分析了暴发流行的主要因素, 并提出了今后的防控对策?     

不同植物秸秆对番茄及南方根结线虫的影响

为有效防治南方根结线虫,本试验研究了添加不同剂量的玉米秸秆(8.32、4.16、2.08g/kg)、辣椒秸秆(4.16、2.08、1.04g/kg)和茵陈蒿秸秆(4.16、2.08、1.04g/kg)对温室大棚番茄及根结线虫的影响。结果显示,在根结线虫侵染的土壤中添加植物秸秆后30d,玉米秸秆(4.16、2.08g/kg)对番茄株高有显著影响,辣椒(4.16、1.04g/kg)和茵陈蒿(4.16、2.08g/kg)秸秆对番茄茎粗影响显著;60d时经茵陈蒿处理的番茄植株比对照生长发育良好,对形态指标的影响程度依次为茎粗开花分枝;120d时番茄的茎粗、分枝和果实重量均显著高于对照。末次接种后20d调查,每种作物秸秆处理以高剂量对根结线虫的防治效果最好,防治效果依次为:茵陈蒿秸秆辣椒秸秆玉米秸秆,分别为79.60%、71.32%、68.89%,表明茵陈蒿秸秆处理既可降低根结线虫危害程度,又可提高番茄产量。本研究为温室大棚有效防治根结线虫提供了依据。     

武汉市2014年秋玉米锈病发生特点与防治措施

<正>我国玉米种植面积3 200万hm2,产量16926.3万t,占全国粮食总产的30%以上,是仅次于水稻和小麦的第三大粮食作物,在农业生产中占有重要位置。近几年武汉市玉米播种面积保持在2万km2左右,其中汉南区种植面积占三分之一,鲜食玉米占三分之一。锈病是玉米的常规性病害之一,往年危害不重,常年主要危害的病害为纹枯病和大、小斑病,但2014年秋玉米锈病发生非常重。据2014年10月上旬普查,玉米锈病发     

甘蓝夜蛾核型多角体病毒对黑龙江省玉米螟防治效果初探

黑龙江省是我国玉米主产区,玉米螟是发生在玉米上的常见害虫,近年来,玉米螟对黑龙江省玉米的危害呈逐年加重趋势。本文在黑龙江省玉米螟重发区对甘蓝夜蛾核型多角体病毒对玉米螟防治效果进行研究,研究结果表明:20亿PIB/mL甘蓝夜蛾核型多角体病毒悬浮剂50mL/667m~2在玉米心叶末期(见雄穗率5%)1次施药防治效果与50 000IU/mg苏云金杆菌(BT)粉剂25g/667m~2在玉米心叶末期(见雄穗率5%)1次施药对玉米螟的防治效果相当,挽回产量损失率最高达10.1%,是较好的玉米螟防治微生物杀虫剂。     

我国玉米南方锈病研究进展

玉米南方锈病是我国玉米的重要病害之一。近年来已成为玉米生产上的严重生物灾害,全国常年发生面积在667万hm2左右,造成了严重的产量和经济损失,如何有效防控已成为亟待解决的生产问题。该文综述了我国玉米南方锈病的发生危害情况、分布、发生流行和传播规律、研究热点及存在的问题等,以期为该病害的研究和有效防控提供参考。     

5种杀菌剂对青贮玉米3种病害的田间防治效果

为有效防治青贮玉米Zea mays Linn.锈病、小斑病和大斑病, 筛选出低毒、无公害的高效防治杀菌剂, 选用哈茨木霉水分散粒剂(1亿cfu/g)、枯草芽孢杆菌可湿性粉剂(1 000亿孢子/g)、37%苯醚甲环唑水分散粒剂、15%三唑酮可湿性粉剂和80%代森锰锌可湿性粉剂5种杀菌剂进行田间药效试验。结果表明, 1亿cfu/g哈茨木霉WG对青贮玉米3种病害的田间防效最优, 37%苯醚甲环唑WG对小斑病的防效最好, 15%三唑酮WP对锈病的防效最理想, 80%代森锰锌WP对大斑病的防效最优。     

Evaluation of fungicide application rates,spray schedules and alternative management options for rust and angular leaf spot of snap beans in Uganda

Yield losses due to rust and angular leaf spot (ALS) of snap beans may reach 100% in Eastern Africa. Where susceptible varieties are grown, farmers control these diseases with routine fungicide applications. To determine an optimum application rate and spray schedule for Orius® (tebuconazole 250 g/L), we sprayed 10 mL and 20 mL Orius® per 15 L spray water twice at two trifoliate leaf stage and 50% flowering, and three times at the same stages, with an additional application at pod initiation. In farmers’ fields, we tested the effect of fungicide sprays, use of resistant variety, intercropping, increased plant spacing and farmyard manure on rust and ALS diseases. Application three times of 20 mL Orius® per 15 L spray water reduced rust severity scores by 5.7 and 2.4 in 2010 and 2011, respectively. Lowest rust and ALS severities were observed when a resistant variety, fungicide or farmyard manure was used. Pod yield increments due to disease management ranged between 13% and 242%. Prophylactic fungicide application, use of resistant varieties and farmyard manure can be used to reduce disease severity and improve snap bean quality on smallholder farms.     

Disease severity and yield of pure-line wheat cultivars and mixtures in the presence of eyespot, yellow rust, and their combination

Five winter wheat cultivars, six two-component cultivar mixtures, and one four-way mixture were grown in the presence of yellow rust, eyespot, both diseases, and neither disease for three seasons. On average, mixtures reduced the severity of yellow rust relative to their component pure stands by 53%. The four-component mixture provided better yellow rust control than did the two-way mixtures. Eyespot severity was reduced through mixing only in the absence of yellow rust and by only three of the seven mixtures (mean reduction = 13%). Yellow rust was 13% less severe in the presence of eyespot, and eyespot was 10% more severe in the presence of yellow rust. Averaged over all years, the mixtures increased yield relative to the pure stands by 6·2, 1·7, 7·1, and 1·3% in the presence of yellow rust, eyespot, both diseases, and neither disease, respectively. Two mixtures provided significant yield increases over the means of their component pure stands (7% and 9%) in the presence of eyespot even though one of them did not significantly reduce eyespot severity. Accounting for all disease treatments and years, four mixtures provided distinctly higher yield increases than the other three. In mixtures containing a resistant cultivar and a cultivar susceptible to eyespot, yield loss by the susceptible cultivar was not compensated for by increased yield of the resistant cultivar. The mixtures showed improved yield stability relative to the pure stands, with the four-component mixture being particularly stable.     

鞘腐病发生程度与玉米倒伏及产量损失间的相关性分析

为深入探讨鞘腐病的发生对玉米倒伏及产量的影响,通过温室接种法测定了玉米不同发育阶段鞘腐病的发病程度及相关防御酶活性,以确定玉米鞘腐病的易感时期;并通过田间接种不同浓度的层出镰孢菌获得不同发病级别的玉米鞘腐病病株,于乳熟期调查病害发生程度,利用YYD-1B数显植物茎秆强度检测仪测定每株玉米茎秆的抗倒伏能力,收获后测定其产量。结果显示,玉米鞘腐病的易感时期为开花期,郑单958和浚单20在此时期鞘腐病的发病率分别为64.36%和40.22%;病情指数分别达42.73和19.58,均高于其它时期;玉米自交系OH43Ht1、郑58和杂交品种郑单958的茎秆抗倒伏能力均随着玉米鞘腐病发病级别的升高而降低;郑58和郑单958的产量随玉米鞘腐病发病级别的升高而降低,每公顷产量损失郑58从13.84%增加到29.53%、郑单958从3.99%增加到16.72%。表明玉米鞘腐病严重发生时能够降低玉米的抗倒伏能力和产量,且对自交系的影响大于杂交品种,生产中应引起高度重视。     

Effect of rust (Uromyces viciae-fabae) on yield components of faba bean

Epidemics of faba bean rust (Uromyces viciae-fabae) differing in duration and final severity were induced by a point inoculation. Relationships between disease severity observed on three canopy layers (top, middle and bottom) at different assessment dates and yield components (grain weight per stem, average grain weight, number of grains per pod and number of pods per stem) were established. Epidemics occurring after the initiation of pod setting had no effect on yield components. Earlier epidemics significantly decreased the grain weight per stem, the average grain weight, and the number of pods per stem, but only marginally affected the number of grains per pod. The yield components generally decreased with increasing severity level, but a few parabolic relationships were observed at a late stage in crop development. The effect of rust on yield components could be predicted by a critical point model using disease severity assessed on the middle or bottom canopy layer in the mid-flowering stage. Rust severity greater than 5% during that critical stage would substantially decrease final yield, and fungicide spraying against rust would be advised.     

4种杀菌剂对紫皮石斛锈病的田间药效评价

针对紫皮石斛锈病。试验选用10%苯醚甲环唑WG,250 g/L嘧菌酯SC,29%吡萘·嘧菌酯SC,75%肟菌·戊唑醇WG 4种杀菌剂进行田间药效试验。结果表明:复配剂29%吡萘·嘧菌酯SC 600 mL/hm~2与75%肟菌·戊唑醇WG 300 g/hm~2,防效相当且显著高于其余两个施药处理,在第3次施药后7 d时达最高防效分别为87.70%和88.56%,鲜重折合产量比空白对照分别增产13.48%、13.22%,可在实际生产中交替使用。     

玉米纹枯病产量损失测定和发生规律

不同地区玉米纹枯病产量损失测定结果表明,产量损失与病情严重度级别之间存在着显著的直线相关,严重度每提高一级,产量损失增加约10％左右,在产量损失的构成中,千粒重下降处于主导地位,粒数的减少其次;始病愈早,发病愈重,相应的产量损失也愈大。不同地区,播期不同,发病期亦不同。从生育期来看,却是基本一致的,玉米抽雄期为发病始盛期,乳熟期为发病高峰期。品种间发病差异明显,但未发现高抗品种,目前生产上广泛应用的掖单系统杂交组合,中抗至中感,其丰产性较好。增施钾肥112.5～262.5kg能显著地减轻病害和增加产量,可作为防病措施推广应用。另外,大田调查还发现,轮作、间作和控制种植密度能减轻病害发生。     

Effect of foliar diseases of wheat on the physiological processes affecting yield under semi-arid conditions

The effects of Septoria leaf blotch (caused by Mycosphaerella graminicola) and leaf rust (caused by Puccinia recondita ) on the physiological processes affecting yield were studied under semi-arid conditions in Israel. In the absence of water stress, photosynthetic activity decreased as the rate of disease development increased. Transpirational activity was reduced in leaves infected by Septoria leaf blotch, but intensified in leaves with slight leaf rust infections (0.5-5% severity). When leaf rust seventy exceeded 5%, the transpirational water loss declined. Both diseases were associated with a decrease in the maximum rate of grain-weight accumulation, but did not affect the duration of weight accumulation. An inverse linear relationship between disease and final grain weight was observed. Under conditions of water stress, photosynthetic activity of leaves slightly infected by Septoria leaf blotch (1-5"., severity) was greater than that of uninfected leaves. Severely infected leaves (" 25% severity) photosynthesized the least. Both diseases were associated with a decrease in the maximum rate of grain weight accumulation, but the duration of accumulation was longer in tillers with a slow rate of disease development than in uninfected tillers. The relationship between disease and final grain weight in these cases was parabolic; yield was increased at low levels of infection. Theoretical explanations and practical implications of these phenomena are presented and discussed.