4种生物药剂对藜麦田甜菜龟叶甲幼虫的防效

选用4种生物药剂,开展施药防治山西朔州藜麦田间甜菜龟叶甲幼虫的试验。试验结果表明,0.5%苦参碱水剂115 mL/667m~2处理防效最高,药后1、3、7 d对甜菜龟叶甲幼虫的防效分别为66.3%、91.4%、99.5%,均显著高于其他供试药剂处理的同期防效。6%鱼藤酮微乳剂50 mL/667m~2、0.5%苦参碱水剂95 mL/667m~2、1.5%除虫菊素水乳剂120 mL/667m~2和160 mL/667m~2处理的防效较高,药后3 d防效均在78%以上,药后7 d均在90%以上。0.3%印楝素乳油两个用量处理的速效性较差,药后7 d防效升至79.3%～82.4%,具有一定持效性。     

湖南省水稻二化螟防治药剂筛选研究初报

近年来二化螟在湖南省水稻上为害严重,对常用杀虫剂的抗性上升,需筛选高效替代药剂。通过田间施药试验,比较不同类型药剂的防治效果。第2次药后16 d,混剂或复配剂防效较高的有5%环虫酰肼悬浮剂50 mL/667m~2+20%三唑磷乳油150 mL/667m~2,残虫防效达92.00%,10%阿维·甲氧虫酰肼悬浮剂100 mL/667m~2防效达90.67%,35%水胺硫磷乳油100 mL/667m~2+90%杀虫单可湿性粉剂60 mL/667m~2防效达89.33%;单剂防效较高的有5%环虫酰肼悬浮剂100 mL/667m~2,防效达89.33%,5%丁虫腈乳油200 mL/667m~2防效为88.00%,40%毒死蜱乳油100 mL/667m~2防效为85.33%。     

2.5%甲氨基阿维菌素苯甲酸盐水分散粒剂对小菜蛾的防治效果

田间药效试验表明,2.5%甲氨基阿维菌素苯甲酸盐水分散粒剂对蔬菜小菜蛾具有良好的防治效果,在生产上,适宜用量为每667m2剂量4～6g,药后3～7d,防效达90%以上,显著或极显著高于对照药剂1.8%阿维菌素乳油每667m2剂量30mL的防效。     

毒死蜱·噻虫嗪30%水乳剂防治稻飞虱药效试验

试验表明,毒死蜱·噻虫嗪30%水乳剂对水稻稻飞虱有很好的防治效果,用药量80mL/667m2药后7、14d的总校正防效分别达90.4%和86.1%,与对照药剂噻虫嗪25%水分散粒剂3g/667m2的防效相当,明显优于对照药剂毒死蜱40%乳油100mL/667m2的防效。该药剂不但防效理想、持效期较长,且安全性良好。     

苏云金杆菌G033A防治萝卜黄曲条跳甲的探索试验

田间药效试验表明32 000IU/mg苏云金杆菌G033A可湿性粉剂对萝卜黄曲条跳甲防治效果较好,每667m2用100g、150g、200g施药后2d防治效果分别为68.2%、78.0%、81.4%,药后5d防效为76.2%、84.1%、89.2%,药后10d防效为73.3%、80.8%、85.1%;每667m2用100g的防效极显著低于对照药剂5%啶虫脒EC的防效,每667m2用150g～200g的防效与对照药剂5%啶虫脒EC无显著差异。根据试验结果认为,推荐用药量为150g～200g/667m2,施药时间选择阴天或晴天傍晚时进行,间隔10d左右视虫情发生情况再进行第2次防治。     

三环·嘧菌酯防控稻瘟病效果初探

以生产中常用的稻瘟病防治药剂为对照,开展稻田施药试验,调查新型复配杀菌剂三环·嘧菌酯防控稻瘟病的效果。结果表明,45%三环·嘧菌酯悬浮剂3个用量处理对水稻穗瘟均具较高防效。其制剂用量40 mL/667m2处理在第2次药后24 d的病指防效为74%,与对照药剂40%氰菌胺悬浮剂处理的防效相当,显著高于另两种对照药剂40%稻瘟灵乳油和6%春雷霉素水剂处理;其50、60 mL/667m2处理的防效更高,第2次药后24 d均达80%以上,显著高于其他施药处理。     

阿维·高效氯氟氰菊酯3.5%微乳剂田间药效试验

田间药效试验结果表明阿维·高效氯氟氰菊酯3.5%微乳剂在15～25mL/667m2的剂量下对甘蓝甜菜夜蛾具有良好的防效.药后10d 20～25mL/667m2剂量杀虫效果达97%以上.     

植保无人机防治稻飞虱的应用示范

本文进行了植保无人机防治水稻稻飞虱的药效试验。结果表明,20%噻虫胺EC 50 ml/667m2、30%噻虫嗪SC 4g/667m2、50%丙威·噻虫胺WP 24 g/667m2、25%吡蚜酮WP 24 g/667m2、11.5%吡·噻EC 100 ml/667m2施药后1 d,5种药的防效均在84%以上,速效性都较好;药后3～10 d,防效都在94%以上,7 d达到高峰,防效在97%以上;药后15 d,几种药剂的防效均保持在85%以上。     

甲氧虫酰肼·乙基多杀菌素360g/L悬浮剂对大葱甜菜夜蛾和蓟马的田间防效

甜菜夜蛾和葱蓟马是为害大葱的重要害虫,为了寻找高效、环境友好且能兼治的药剂,特进行了本研究。结果表明:甲氧虫酰肼·乙基多杀菌素360g/L悬浮剂对甜菜夜蛾的防效在施药后第1、3、7d逐渐提高,药后第10d在24.4g/667m2的剂量下,防效可达98.40%;对葱蓟马防效药后第3d最好,在24.4g/667m2的剂量下,平均防效为74.56%,药后第7、10d防效略有降低。因此,甲氧虫酰肼·乙基多杀菌素360g/L悬浮剂可作为大葱田防治甜菜夜蛾和蓟马的优良药剂。     

春雷霉素·噻唑锌40%悬浮剂防治水稻稻瘟病试验初报

田间药效试验结果表明,春雷霉素.噻唑锌40%悬浮剂对水稻稻瘟病有较好的防治效果,其药效随用药量加大而显著上升,其中第2次药后14d 40mL/667m2的校正防效达80.91%,极显著优于对照药剂噻唑锌20%悬浮剂120mL/667㎡的校正防效,与对照药剂春雷霉素2%液剂80mL/667m2的校正防效相当,且安全性好,因此可以在生产上加以推广应用。     

百菌清在甘蓝叶片上的光化学降解

为研究百菌清在甘蓝叶片中的光化学降解，利用高效液相色谱外标法探究了甘蓝叶片的水提取液在氙灯、紫外灯2种光源下对百菌清的光化学降解作用效应；研究了百菌清在花青素含量差异较大的绿甘蓝和紫甘蓝叶片表面的降解行为。结果表明:在氙灯光照下，百菌清在绿、紫甘蓝叶片水提取液中的光降解半衰期分别为80.58 min和70.71 min，降解速率分别是未添加甘蓝叶片水提取液百菌清水溶液的7.17倍和8.71倍；除光催化氧化和光催化还原作用外，百菌清在甘蓝叶片水提取液作用下还可产生光催化水解反应。在紫外灯光照下，百菌清在绿、紫甘蓝叶片表面的降解符合一级动力学规律，光降解半衰期分别为12.68 h和11.25 h；将甘蓝叶片进行创伤处理后，百菌清的光降解速率明显加大。该研究结果可为百菌清在不同蔬菜上的科学使用及其食用安全性风险评价提供参考。     

防治白菜根肿病的药剂筛选

分别采用拌药法和灌药法,比较了10种供试药剂对白菜根肿病的温室防治效果,并对盆栽试验防效较好的3种药剂进行了田间药效试验。结果表明,在温室条件下,50%氟啶胺悬浮剂(1 g/m3)、50%甲基硫菌灵可湿性粉剂(25 g/m3)、70%代森锰锌可湿性粉剂(35 g/m3)和40%五氯硝基苯粉剂(20 g/m3)的拌药处理,对白菜根肿病的防效均在50%以上,显著优于灌药处理的防效。田间药效试验结果表明,50%氟啶胺悬浮剂(2 g/m3)拌药处理的防效在80%以上,与盆栽药效试验结果一致,并显著优于其他药剂处理。     

甘蓝枯萎病病原菌的鉴定

 采用温室接种致病性测定、形态学观察和分子鉴定方法对甘蓝枯萎病病原进行了研究。从北京市延庆县9个甘蓝生产基地采集甘蓝枯萎病病样96份,分离获得来自甘蓝病株根、短缩茎、叶片等器官的30个真菌分离物。经过致病性试验证实,分离物GLW3和GLW8为甘蓝枯萎病病原菌。经形态学鉴定,GLW3为尖孢镰刀菌(Fusarium oxysporum),GLW8为轮枝样镰刀菌(Fusarium verticillioides)。利用镰刀菌的核糖体DNA(rDNA)内转录间隔区(internal transcribed spacer,ITS)的保守性和变异性,分别采用真菌通用引物和镰刀菌属及轮枝样镰刀菌特异性引物对GLW3和GLW8进行PCR扩增,并将测序结果在GenBank中进行同源性比对分析,分子鉴定与形态学鉴定结果一致。轮枝样镰刀菌作为甘蓝枯萎病的病原菌系首次报道。     

大白菜根肿病化学防治技术

在大白菜的不同生育期,采用多种杀菌剂和不同的防治方法防治大白菜根肿病,试验结果表明: 50%氟啶胺和10%氰霜唑能有效防治大白菜根肿病,其防治效果优于其他化学药剂。在播种前用10%氰霜唑悬浮剂2 000倍液浸种,再用50%氟啶胺悬浮剂300倍液对苗床土壤和大田土壤进行消毒处理,对大白菜根肿病的防治效果可达85.70%,比清水对照增产42.32%。     

白菜根肿病的接种方法

根肿病是由芸薹根肿菌Plasmodiophora brassicae Woronin引起的土传性病害.根肿菌属于专性寄生菌,不能直接培养,所以对带菌植株活体的研究尤为重要,而建立稳定的接种方法是带菌植株活体研究的基础.Asano等曾提出过浸醮法、插入法和菌土法等接种技术,但至今国内外对十字花科根肿病还没有统一且稳定的接种方法.为此,本试验对白菜根肿病的接种方法进行了研究.     

Field efficacy of three insecticides against cabbage stink bugs (Heteroptera: Pentatomidae) on two cultivars of white cabbage

Abstract

In 2002 – 2003, three insecticidal substances were tested for their ability to reduce the damage inflicted on plants of white cabbage by cabbage stink bugs, Eurydema ventrale and E. oleracea (Heteroptera: Pentatomidae). The two cultivars of cabbage tested were: the early cultivar, ‘Tucana F₁’, which requires about 60 days from transplanting to harvest, and the mid-early cultivar ‘Hinova F₁’, which requires about 120 days. In a field experiment, the growth and damage on cabbage plants sprayed with malathion (two sprays), potassium soap [potassium salts of fatty acids] (five sprays), and refined rape oil (five sprays) were compared to the growth and damage on unsprayed plants. Potassium soap and refined rape oil are considered to be environmentally friendly insecticides. In 2002, plants of the cultivar ‘Tucana’, that were treated with malathion had the highest plant weights [PW], head weights [HW], HW/PW ratio, and the lowest number of frame leaves. In the drier year of 2003, there were no significant differences in damage between the three treatments for either cultivar, except during the last assessment done on 13 August. In 2003, plants of ‘Tucana’, treated with potassium soap, had the highest PW and HW. The significantly lowest PW and HW values were recorded from the untreated plants. For the cultivar ‘Hinova’, the PW and HW were heaviest from the plants treated with malathion. In both years, the HW/PW ratio of Hinova (mid-early cultivar) did not differ between treatments, while the plants of ‘Tucana’ (early cultivar) treated with malathion had the highest ratio. Of the three substances tested, malathion was the most effective at reducing the damage on white cabbage plants caused by cabbage stink bugs. However, in an attempt to reduce the use of synthetic insecticides, instead of malathion, we recommend the use of refined rape oil (49 EUR/ha), as it is as effective as potassium soap (81 EUR/ha), but much cheaper.     

Root rot of cabbage caused by Phytophthora drechsleri

A root rot of cabbage is reported from South Africa. The causal pathogen was identified as Phytophthora drechsleri , based on morphological characters and electrophoretic patterns of soluble proteins.     

Induced resistance to Peronospora parasitica in red cabbage

A culture filtrate ofCalcarisporium arbuscula, ether extract prepared from it, yeast extract and 2,6-dichloroisonicotinic acid (INA) were tested for their disease-reducing effects onPeronospora parasitica on red cabbage. Yeast extract and culture filtrate or ether extract fromC. arbuscula were only moderately effective. INA gave good results, the EC₅₀ was about 1 mg 1^?1.     

草地贪夜蛾在浙江为害甘蓝

草地贪夜蛾于2019年1月入侵我国云南省江城县,随后在多个省份发现其为害玉米,4月份以来在部分地区陆续发现其为害甘蔗、高粱等作物。作者于2019年10月5日在浙江省杭州市甘蓝上发现草地贪夜蛾高龄幼虫造成局部为害,平均每株幼虫0.62头,有虫株率达25%。建议今后加强蔬菜作物上该虫的监测和综合防控。     

Clonal populations of Leptosphaeria maculans contaminating cabbage in Mexico

The race structure and genotypic diversity of four Leptosphaeria maculans populations isolated from Brassica oleracea (broccoli, cauliflower, cabbage, etc.) in central Mexico (Aguascalientes, Guanajuato and Zacatecas states) were analysed. Race structure was characterized by an unusually low diversity at three locations out of four. Fourteen minisatellite markers revealed a high proportion of repeated multilocus genotypes in these populations, combined with a significant linkage disequilibrium and strong clonal fraction (65–87%). The occurrence of the mating‐type idiomorphs always significantly departed from the 1:1 proportion expected in the case of random mating. Each population thus consists of a few (four to nine) multilocus genotypes which are specific to each location. These data strongly support the hypothesis of exclusive, or a high rate of, clonal multiplication. Comparison of cropping practices between B. oleracea and B. napus indicate that the shift in reproductive behaviour of the fungus is chiefly man‐mediated.