Background The fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith), is known to cause large agricultural production losses. Emamectin benzoate is one of the most effective insecticides to control this pest; however, its effective time is not sufficiently long to control FAW. Therefore, it is important that new controlled insecticide formulations with new application methods are developed. Results A series of emamectin benzoate polymer gel granules were prepared with sizes ranging from 0.95 to 1.5 mm. As the bentonite content increased, the release rate decreased. The cumulative release process of emamectin benzoate mainly depends on the cracks in the surface of the granules, and the release rate can be described by non-Fickian and Fickian diffusion, which are closely related to the water content. By spreading the developed polymer gel granules into maize leaf whorls, the control effect reached 83% after 21 days in field trials. Conclusion A novel polymer gel granule was developed that can effectively regulate emamectin benzoate release. By broadcasting polymer gel granules into maize leaf whorls, significant control efficacy against FAW can be obtained, and this could potentially be used for the effective control of FAW. (c) 2022 Society of Chemical Industry.

[Objective]The effects of glyphosate,acetochlor and their combination on soil nutrients and enzyme activities in cabbage field were studied,so as to provide scientific basis for their production and application.[Method]The effects of different treatments[equal amount of water(CK),glyphosate(T1),acetochlor(T2),glyphosate+acetochlor(T3)]on soil nutrients and enzyme activities in cabbage field were investigated by field experiments.[Result]Organic matter,total nitrogen,available nitrogen,total phosphorus,available phosphorus,total potassium and available potassium with different treatments ranged from 45.34 to 46.25 g/kg,2.43 to 2.54 g/kg,0.28 to 0.29 g/kg,0.69 to 0.71 g/kg,21.34 to 25.75 mg/kg,3.10 to 3.25 g/kg and 0.10 to 0.14 g/kg,with T1,T1/CK,T3,T2/T3,CK,T3 and CK being the highest,and T2,T2,T1/T2/CK,T1/CK,T1,T1 and T1 being the lowest,respectively.Among them,organic matter,total nitrogen,available nitrogen,total phosphorus,available phosphorus and total potassium did not differ significantly among treatments,and available potassium in CK was significantly higher than in T1.Catalase,acid phosphatase,urease and sucrase were 2.84-2.92 mL/(g·24h),4.08-4.87 μg/(g·24 h),14.37-15.92 mg/(g·24 h),and 8.00-9.43 mg/(g·24 h),respectively,as T3,CK,CK and T1 were the highest,and T1,T2,T1 and CK were the lowest.Catalase in T3 was highly significant higher than T1,and acid phosphatase,urease and sucrase did not differ significantly among treatments.[Conclusion]The effects of three treatments on soil available phosphorus and available potassium content were more obvious,and the effects on soil organic matter,total nitrogen,available nitrogen,total phosphorus and total potassium were relatively insignificant.The high-frequency use of herbicides should avoid during production,and the herbicides should be combined with agricultural,physical and chemical control measures to carry out integrated prevention and control.

[目的]明确赫章县半夏田杂草的种类组成和群落特征,为半夏田杂草防控及综合治理提供参考.[方法]采用倒置"W"9点取样法连续3年对赫章县半夏主要种植区域杂草进行跟踪调查,分析杂草种类.[结果]赫章县半夏主产区杂草有45种,隶属于17科41属,其中优势杂草有马唐、狗尾草、牛膝菊、野艾蒿、金荞麦、尼泊尔蓼和藜共7种,区域性优势杂草有繁缕、鸭跖草和婆婆纳共3种,常见杂草8种,一般杂草27种.[结论]不同区域杂草发生种类及群落结构有所差异,但主要优势杂草发生情况相对稳定.

通过开展田间施药试验调查并比较了 10种杀虫剂对草地贪夜蛾的防治效果.药后3d,除20％氟苯虫酰胺悬浮剂防效低于80％外,其余9种农药的防效均高于90％,表现出较好的速效性;药后14d,11％甲维·氟铃脲水分散粒剂、15％虫螨·茚虫威悬浮剂、8％阿维·茚虫威水分散粒剂、30％吡丙·虫螨腈悬浮剂防效仍能保持在85％以上,表现出较好的持效性.

为明确贵州甘蓝主产区甘蓝田间杂草发生情况,采用对角线五点取样法对贵州息烽县、修文县和开阳县的春甘蓝田杂草发生情况进行调查.结果表明:息烽、修文、开阳的春甘蓝田共有18种杂草发生,其中禾本科3种,菊科5种,玄参科2种,石竹科、毛茛科、茜草科、蓼科、豆科、十字花科、伞形科、车前科各1种.贵州春季甘蓝田间禾本科杂草主要为棒头草、早熟禾、看麦娘;阔叶类杂草主要为猪殃殃、毛茛、繁缕、泥胡菜、稻搓菜、皱叶酸模,其次为婆婆纳、碎米荠、小飞蓬、鼠麴草、野艾蒿、大巢菜、水芹菜、车前草等.不同区域和不同田块的杂草主要发生种类不同,与当地耕作制度、除草剂使用、施肥情况及气候因素等密切相关.

[目的]草害是制约贵州半夏产业发展的重要因素之一.生产上主要依靠人工除草方式,其除草成本高;化学除草是降低半夏田除草成本的有效措施,但生产上供选择的除草剂品种单一;试验旨在提供更多除草剂品种供半夏田选择应用.[方法]选用5种土壤处理除草剂,按照随机区组设计进行田间药效试验,在半夏播后苗前进行土壤喷雾处理.[结果]50％硝磺草酮?乙草胺?莠去津SC 1500 g a.i./hm2处理、68.8％嗪草酮?乙草胺EC 1543.5 g a.i./hm2处理对半夏田杂草防除效果最好,药后30、45d对杂草群体总株防效、总鲜重防效均在92％以上,但50％硝磺草酮?乙草胺?莠去津SC易产生药害,不宜使用;其次为960 g/L精异丙甲草胺EC 864 g a.i./hm2处理、240 g/L乙氧氟草醚EC 180 g a.i./hm2处理,总株防效、总鲜重防效在69％以上;450 g/L二甲戊灵CS 742.5 g a.i./hm2处理虽药后30 d对杂草群体总防效较好,但45 d防效较差.[结论]除50％硝磺草酮?乙草胺?莠去津SC外,其余4种除草剂均可在半夏田应用.但各除草剂对不同杂草种类防效存在一定差异,应根据半夏田杂草发生情况合理选择,科学用药,保障半夏产品质量安全.

贵州所处地理环境致使幼龄茶园杂草发生频次快、周期长,防控难度大、投入成本高.为丰富及优化茶园覆盖控草技术,采用稻草、玉米秸秆、稻草草帘、黑色防草布4种覆盖控草模式开展幼龄茶园控草效果及对土壤含水量和pH的影响研究.结果 表明,不同覆盖控草模式对幼龄茶园杂草均有较好的控制效果,盖度防效均高于66％、鲜重抑制效果均高于58％;以黑色防草布覆盖处理控草效果最好,盖度防效和鲜重抑制效果均达100％;其次为稻草草帘覆盖,盖度防效93.08％、鲜重抑制效果74.74％.不同覆盖处理同清耕比较均可保持土壤含水量,对土壤pH值也存在一定影响.从控草效果和节约成本方面考虑,长期来看以黑色防草布覆盖处理较好;从改善土壤肥力和对茶树生长角度考虑,以秸秆覆盖处理较为理想,不同覆盖模式均可在茶园推广应用.生产上可根据实际需要,因地制宜,选择覆盖控草模式.

为揭示温度对烟草黑胫病菌Phytophthora nicotianae致病力及代谢表型的影响,采用菌丝生长速率法和离体叶片法分别测定不同温度下烟草黑胫病菌的生长速率和致病力,同时采用Biolog代谢表型技术测定其在20、27、30和35℃下的渗透压和pH代谢表型.结果表明,烟草黑胫病菌在21～35℃范围内生长良好且具致病力,30℃时生长速率最快,为17.72 mm/d,30℃和35℃时致病力较强,叶片接种烟草黑胫病菌后24 h内便出现病斑,随温度升高病害的潜伏期缩短.温度影响烟草黑胫病菌的渗透压和pH适应性;27℃和30℃时烟草黑胫病菌的渗透压适应范围最广,其次为21℃,35℃时烟草黑胫病菌渗透压适应范围最窄;在20、27和30℃时,烟草黑胫病菌在pH 5.0～10.0范围内可正常代谢,在35℃时pH代谢范围为5.5～10.0.

菜青虫是十字花科蔬菜上的重要害虫,严重影响蔬菜的产量和品质,每年都造成重大经济损失.利用喷雾法测试了一种高效氯氰菊酯微囊悬浮剂对菜青虫的药效.结果表明:该药在其有效成分22.50～33.75 g/hm2范围内,施药后2 d、5 d、10 d对甘蓝菜青虫的防效分别为86.37％ ～93.89％、90.80％ ～95.80％、86.03％ ～91.40％.说明其对甘蓝菜青虫具较好的防效,且持效期较长,具有良好的生产应用价值.故推荐采用其有效成分22.5～33.75 g/hm2在生产上防治甘蓝菜青虫的危害,且菜粉蝶卵孵化盛期至菜青虫1、2龄高峰期为最佳施药防治时期.

蓝莓是一种原产于北美洲及东亚、我国北部地区的多年生低灌木.蓝莓果渣是蓝莓果汁、果酒加工副产物.果渣中的功能性成分与果实相近,具有降血脂、抗肿瘤、调节免疫力等功效.文章综述了蓝莓果渣主要功能性成分、功效及综合利用的国内外研究进展,提出了目前研究存在的不足,并对未来研究方向进行了简要展望,可为蓝莓果渣综合开发利用提供参考.

采用气相色谱(μ-ECD)开发了高效氯氟氰菊酯在万寿菊上的残留分析方法,利用QuChERS前处理方法,经乙腈提取、PSA净化,氮气吹干后用正己烷定容,外标法定量.高效氯氟氰菊酯在万寿菊中的添加回收率为97％～99％,相对标准偏差在4.0％～8.5％.笔者建立了万寿菊中高效氯氟氰菊酯气相色谱残留分析方法,能够满足万寿菊样品中的高效氯氟氰菊酯的定量分析,并对万寿菊高效氯氟氰菊酯最终残留量进行了检测,样品中的高效氯氟氰菊酯均未检出.

为了解烟草种子附生真菌的群落结构和多样性.采用Illumina MiSeq高通量测序技术测定K326、云烟85、L8、301种子的附生真菌.结果表明K326种子的优势属为链格孢属(Alternaria)、赤霉菌属(Gibberella)、隐球菌属(Cryptococcus)、镰刀菌属(Fusarium)及红酵母属(Rhodotorula)等;云烟85的优势属为赤霉菌属、小画线壳属(Monographella)、链格孢属、红酵母属及镰刀菌属;301的优势属为链格孢属;L8的优势属为链格孢属、曲霉菌属、镰刀菌属、赤霉菌属及隐球菌属等.

为猕猴桃桑白蚧的防治提供参考,采用螺虫乙酯、呋虫胺、烯腚虫胺、吡蚜酮和吡虫啉5种农药原药制成贴膏,进行树干包裹,比较不同农药种类对桑白蚧的防治效果.结果表明:呋虫胺对桑白蚧的防治效果最好,15 d和30 d防治效果分别达到97.56％和95.97％,呋虫胺贴膏的防治效果与螺虫乙酯、吡蚜酮和吡虫啉药剂相比存在极显著差异.

为修文猕猴桃桑白蚧的防治提供参考,试验设置0 g/100mL、1.25 g/100mL、2.5 g/100mL和5 g/100mL的呋虫胺农药贴膏贴在猕猴桃主干上,间隔15 d和30 d用手持放大镜调查活虫数和死虫数.结果表明:2.5 g/100mL和5 g/100mL农药贴膏对桑白蚧30 d的综合防效分别达96.78％和97.58％.综合成本问题,建议生产上推广应用2.5 g/100mL农药贴膏.

[目的]测定贵州省不区域空心莲子草种群对草甘膦的敏感性.[方法]通过室内整株盆栽法测定10个未使用和20个使用过草甘膦的空心莲子草对草甘膦的ED50值.[结果]未使用过草甘膦的空心莲子草对草甘膦的敏感基线为104.41 g a.i./hm2,惠水县好花红镇满定村种群敏感性最低,ED50值为43.02 g a.i./hm2,其他种群的相对抗性倍数在1～6.2之间,56.7％种群处于低水平抗性,33.3％种群处于敏感阶段.[结论]贵州空心莲子草种群尚未超过草甘膦田间推荐剂量,对草甘膦的抗性程度不高.

采用倒置"W"9点取样法对贵州省不同区域茶园杂草进行调查,以明确贵州省茶园杂草发生危害特点,为贵州省茶园杂草防控提供依据.结果表明,贵州省茶园杂草有152种(含变种),隶属于42科122属,其中优势杂草11种,区域性优势杂草10种,常见杂草20种,一般杂草111种,以马唐、繁缕、野茼蒿、姬蕨、小蓬草、白茅、野艾蒿、胜红蓟、鬼针草、牛膝菊、马兰等为优势杂草;不同区域茶园杂草群落存在一定差异,对于成年茶园,其杂草发生种类,多年生杂草发生比例较幼龄茶园高,但二者均以一年生杂草发生为主.

为了降低农药使用量,提高防治效果,在省水、省药、省时方面,评价了低容量连杆多喷头喷雾组件电动喷雾器对草地贪夜蛾的防治效果.结果 表明:和常规喷雾器械相比,低容量连杆多喷头喷雾组件能够节省用水64.9％,平均节省用药64.9％,缩短施药时间32.2％.低容量连杆多喷头喷雾组件具有高效、省药的特点,对防治草地贪夜蛾具有良好的防治效果.

In order to clarify relationship between development, host choice of the oriental aryworm, Mythimna separata and content of biochemical substances in different maize varieties, the development duration, feeding and reproduction choice of this pest on 22 maize varieties was observed under the libaratory conditions of 25±1 ℃, 70％-80％ RH and a photoperiod of 14 L∶10 D, and content of four biochemical substances in 22 maize varieties were also investigated.The results showed that the M.separata exhibited significant difference in the development andpupa mass among tested corn varieties, but the eclosion rate had no difference.The development duration of larval+pupa was the shotest on Qiandan 16 variety (26.14 d), and the longest on 8017 variety (29.36 d).The heaviest pupa mass was observed on Andan 3 variety (346.84 mg) and the lightest was observed on 7079 variety (298.71 mg).The highest surval rate was found on Qiandan 16 variety (93.33％), while the lowest was found on 8021 variety (66.87％).The M.separata had obvious feeding and reproduction choice on different corn varieties, and this pest profered to reproduction (5.67 mass per plant) and feeding (9.00 pest per plant) on Qiandan 16 variety.Content of total phenols, flavonoids and total protein were significantly different among maize varieties, but the content of total sμgar was not different.Correlation analysis showed that content of these substances were not associated with development of M.separata.Development, survial and host choice of M.separata are obviously different among 22 maize varieties, which are not associated with the content of 4 tested biochemical substances.

Superoxide dismutase (SOD) is an antioxidant metalloenzyme that catalyzes the dismutation of the superoxide anion O-2(-) to O-2 and H2O2. Many studies have focused on the role of SOD in response to abiotic stress, but its role during biotic stress, such as changes in organismal population density, has rarely been investigated. The oriental armyworm, Mythimna separata, is an economically important pest that exhibits phenotypic changes in response to population density. Solitary and gregarious phases occur at low and high population density, respectively. To examine the role of SODs in response to population density stress, we cloned two genes encoding SOD, MsCuZnSOD and MsMnSOD, and compared their expression in solitary and gregarious phases of M. separata. The MsCuZnSOD and MsMnSOD ORFs were 480 and 651 bp and encoded predicted protein products of 159 and 216 amino acids, respectively. The two SODs contained motifs that are typical of orthologous proteins. Real-time PCR indicated that the two SOD genes were expressed throughout developmental stages and were significantly upregulated in more mature stages of gregarious M. separata. Expression of the two SOD genes in various tissues of sixth-instar larvae was higher in gregarious versus solitary insects. Furthermore, expression of the SOD genes was significantly upregulated in response to crowding in solitary individuals, but suppressed in gregarious insects subjected to isolation. Collectively, these results suggest that population density may be key factor in the induction of SOD genes in M. separata.

为评价烟草赤星病致病菌链格孢Alternaria alternata对嘧菌酯的抗性风险,以敏感菌株J6为试材,通过菌丝药剂驯化和分生孢子紫外诱变诱导抗性突变体,并对抗性突变体的生物学特性进行了研究,同时对抗性突变体与敏感菌株线粒体的细胞色素b基因(cyt b)cDNA序列全长进行了测序分析.结果表明:经药剂驯化未获得抗性突变体,而紫外诱变共获得7株抗性突变体,突变频率约为0.007％,抗性水平分别为5.27、8.28、25.28、12.82、6.14、9.28和52.91倍.适合度研究表明,抗性突变体与敏感菌株的分生孢子萌发能力及致病力相当,但分生孢子产生量均高于敏感菌株,菌丝生长速率除突变体6-1外均快于敏感菌株.cyt b基因cDNA序列分析表明:有4株抗性突变体在不同位点上发生了核苷酸突变,其中突变体6-7 cyt b的249位和871位碱基由T突变为C,但其编码的氨基酸未发生突变;突变体6-8 cyt b的734位碱基由T突变为C,引起所编码的245位丙氨酸突变为缬氨酸(V245A);突变体6-9 cyt b的510位碱基由T突变为A,所编码的170位由精氨酸替代了丝氨酸(S170R);突变体6-11 cyt b的732位碱基由T突变为A,所编码的244位由苯丙氨酸替代了亮氨酸(L244F),其776位碱基由T突变为C,所编码的259位由丙氨酸替代了缬氨酸(V259A),其1156位碱基由A突变为G,所编码的氨基酸未发生变化.研究结果初步表明,烟草赤星病菌对嘧菌酯存在潜在的抗药性风险,其cyt b基因的点突变与其对嘧菌酯的抗药性有关.