氟环唑对广东水稻纹枯病的田间防治试验

连续2009-2010两年田间药效试验结果表明,试验药剂氟环唑125g/L悬浮剂对水稻纹枯病具有较好防效,施药用量为有效成分75g/hm2处理的末次防效达72%以上,保产率达12%以上,是防治水稻纹枯病较为理想的药剂,对水稻安全。     

24%咪鲜胺·噻呋酰胺SC防治水稻纹枯病试验

对24%咪鲜胺·噻呋酰胺SC防治水稻纹枯病的田间药效进行了试验。结果表明,24%咪鲜胺·噻呋酰胺SC 450g/hm2处理后对水稻纹枯病的防效达到87.44%,高于对照药剂240g/L噻呋酰胺SC 187.5g/hm2防效80.37%和对照药剂25%咪鲜胺EC 750g/hm2防效77.37%。说明24%咪鲜胺·噻呋酰胺是一种防治水稻纹枯病的优良制剂,可在生产上大面积推广和应用。     

3种药剂防治水稻纹枯病、稻曲病和稻瘟病田间药效试验

采用田间药效试验方法,比较3种药剂对水稻纹枯病、稻曲病、稻瘟病的防治效果。结果表明:3种药剂对水稻纹枯病、稻曲病、稻瘟病都有一定防效。其中75%肟菌戊唑醇水分散粒剂225 g/hm2对水稻纹枯病、稻瘟病防效最好,防效分别为85.74%、85.19%;43%戊唑醇悬浮剂225 mL/hm2对稻曲病的防治效果最好,防效为88.25%。综合防治效果表明,75%肟菌戊唑醇水分散粒剂150～225 g/hm2对水稻纹枯病、稻曲病、稻瘟病的防效最好,43%戊唑醇悬浮剂225 mL/hm2对稻曲病和纹枯病防治效果较好,在实际生产上可广泛应用。     

宝应县不同药剂对水稻纹枯病的防治效果研究

水稻纹枯病是江苏省宝应县水稻生产上的主要病害之一,给水稻生产带来巨大的损失,该研究对市场上防治纹枯病的主要药剂品种进行田间药效对比试验.结果表明,供试的7种药剂对水稻的长势没有产生不良影响,对生产安全,可有效防控水稻纹枯病.其中75%肟菌·戊唑醇可湿性粒剂10g/667m~2和75%戊唑·嘧菌酯可湿性粒剂10g/667m2防治效果最好,药后30d防效均可达80%以上,可作为防治水稻纹枯病的首选药剂.     

30%苯醚甲环唑·丙环唑防治水稻纹枯病田间试验

为了明确30%苯醚甲环唑·丙环唑(爱米)对水稻纹枯病的防治效果,进行了田间药效防治试验。结果表明,30%苯醚甲环唑·丙环唑乳油防治水稻纹枯病每667m2用量20g、15g和10g的3个处理防效分别为84.5%、75.4%和68.54%,对照药剂30%苯醚甲环唑·丙环唑(爱苗)乳油每667m2用量20g和43%戊唑醇(好力克)悬浮剂每667m2用量15g的防效分别为83.4%和69.1%。30%苯醚甲环唑·丙环唑可作为防治水稻纹枯病的药剂,在试验剂量下对水稻安全,可以大面积推广应用,生产上推荐每667m2用量为15～20g。     

高产栽培模式水稻纹枯病的防治效果试验

针对高产栽培水稻纹枯病发生发展快、常用药剂防效差的特点,于2009年6—7月在思南塘头667hm2高产示范区,采用30%爱苗乳油、55%生势可湿性粉剂等农药进行了水稻纹枯病的防效试验。结果表明,30%爱苗乳油、55%生势可湿性粉剂等对水稻纹枯病防效较好,第二次药后7d和15d的防效均与20%井冈霉素的防效差异极显著,且对水稻生长无不良影响,可作为高产栽培水稻纹枯病防治的有效药剂推广使用。     

几种药剂对水稻纹枯病的防治效果探究

使用250g/L嘧菌酯SC 30g/667m~2、240g/L噻呋酰胺SC 30ml/667m~2、5%己唑醇SC 80ml/667m~2、5%井冈霉素SP 100g/667m~2防治水稻纹枯病,于水稻纹枯病发病初期施第1次药,以后每隔7d施1次,共施3次,3次施药后10d各药剂的防治效果均达67.9%~88.9%。其中,嘧菌酯、噻呋酰胺和己唑醇这3种药剂的防效好且相当,为88.0%~88.9%,井冈霉素处理的防效差显著低于以上3种药剂处理的防效,为67.9%。     

30％苯醚·丙环唑悬浮剂防治水稻纹枯病田间药效对比试验

试验结果表明,30％苯醚甲环唑·丙环唑SC对水稻纹枯病有较好防效,施药用量为有效成分112.5g/ha处理的末次防效达78％以上,保产率达8.4％以上,是防治水稻纹枯病较为理想的药剂,对水稻安全.     

丙环·嘧菌酯防治水稻纹枯病效果初探

研究新型杀菌剂18.7%丙环·嘧菌酯悬乳剂对水稻纹枯病的防治效果和对水稻产量的影响。结果表明,该药剂对水稻纹枯病具有良好防效,30~50 m L/667m2的制剂用量防效可达70%以上,并有利于水稻生长,药剂处理较空白对照增产7.28%~14.56%。     

防治水稻纹枯病药剂田间筛选试验

为筛选生产上防治水稻纹枯病的高效、安全药剂,于2014年8月在田间进行了防治纹枯病10种药利筛选试验。结果表明,嘧菌酯类和噻呋酰胺类复配剂防效突出。24%密菌酯·己唑醇悬浮剂20 mL/667m~2、24%噻呋·咪鲜胺悬浮剂30 mL/667m~2处理对水稻纹枯病的株防效超过或接近85%,病指防效均达90%以上,值得进一步示范推广。     

日光温室不同水分条件下盆栽黄瓜产量和土壤微生物数量

在日光温室内盆栽条件下,研究土壤水分对黄瓜产量和土壤微生物数量的影响,结果表明(1)土壤水分含量初花期和初瓜期为田间持水量的80%～90%、盛瓜期90%～100%、生育后期70%～80%的处理黄瓜产量最高,为389.65g/株;其次为初花期土壤水分为田间持水量的90%～100%、初瓜期80%～90%、盛瓜期70%～80%、生育后期90%～100%的处理,产量为351.49g/株;初花期土壤水分为田间持水量的80%～90%、初瓜期90%～100%、盛瓜期70%～80%、生育后期80%～90%的处理产量最低,为257.54g/株。(2)不同水分处理土壤微生物的数量变化不同黄瓜初花期,土壤水分为田间持水量80%～90%的处理土壤细菌数量最多,土壤水分为田间持水量70%～80%的处理和90%～100%的处理土壤细菌数量少,且二者差异不大。黄瓜初瓜期和盛瓜期当土壤水分由低变高时细菌数量增加,相反细菌数量减少,黄瓜生育后期当土壤水分从高变低时细菌数量增加,水分稳定不变或从高变为中等水平或从低变为中等水平时细菌数量减少。土壤真菌数量在土壤水分含量低时和土壤水分相对稳定的情况下增加,否则减少。各处理土壤放线菌在黄瓜初花期和初瓜期数量差异不大,盛瓜期各处理土壤放线菌的数量增加,生育后期多数处理土壤放线菌的数量有所下降。     

水分胁迫对大豆结荚期光合生理及生物量的影响

以秦豆8号为材料进行盆栽试验,研究了大豆苗期、花期及结荚期不同土壤控水处理对大豆结荚期光合生理和生物量的影响。结果表明:当苗期-花期前土壤相对含水量控制为65%~75%情况下,在花期分别进行轻度(土壤相对含水量控制为55%~65%)、中度(土壤相对含水量控制为45%~55%)水分胁迫,结荚期复水至正常供水后,与对照(大豆不同生长阶段土壤相对含水量均保持为65%~75%)相比,随胁迫程度的加剧光合速率(Pn)、蒸腾速率(Tr)、胞间CO2浓度(Ci)、气孔导度(Gs)降幅加大,中度胁迫下分别降低13.16%(P<0.05)、28.60%(P<0.01)、7.64%、49.51%(P<0.01),而气孔限制值(Ls)、叶片温度(T1)较对照有所提高,中度胁迫下分别提高48.07%(P<0.01)、0.36%;当苗期-花期正常供水结荚期分别进行轻度、中度胁迫时,Pn、Tr、Ci、Gs较对照均降低,而Ls及T1较对照提高。当苗期-花期前土壤相对含水量控制为55%~65%情况下,在花期或结荚期进行中度胁迫均使Pn、Tr、Ci、Gs降低,Ls及T1升高,复水后则反之。当苗期-花期前土壤相对含水量为45%~55%时,不论花期或结荚期进行正常供水或轻度胁迫,各处理Pn、Tr、Ci、Gs均高于对照(大豆不同生长阶段土壤相对含水量均保持为45%~55%),而Ls及T1低于对照。当苗期-结荚末期土壤相对含水量连续控制在3个水平条件下,随土壤含水量的降低,Pn、Tr、Ci、Gs呈下降趋势,而Ls及T1升高。当苗期-花期前分别进行正常供水、轻度胁迫、中度胁迫控水处理时,不同处理结荚期单株生物量呈显著差异,中度胁迫与轻度胁迫各处理的单株生物量差值小于正常供水与轻度胁迫各处理单株生物量差值。     

8%辛硫磷微乳剂对蚜虫和斜纹夜蛾的防治效果

采用盆栽法,测定8%辛硫磷微乳剂不同浓度对蚜虫和斜纹夜蛾药后1~3 d虫口减退率和防治效果.结果表明,8%辛硫磷微乳剂375 g ai./hm2处理对蚜虫防效显著优于对照药剂40%辛硫磷乳油375 g ai./hm2处理,93.75~187.5 g ai./hm2处理与对照药剂40%辛硫磷乳油375 g ai./hm2处理无显著差异;8%辛硫磷微乳剂400 g ai./hm2处理对斜纹夜蛾防效与对照药剂40%辛硫磷乳油400 g ai./hm2处理相当.8%辛硫磷微乳剂对蚜虫和斜纹夜蛾具有良好的防治效果,可用于防治十字花科蔬菜蚜虫和斜纹夜蛾.     

戊唑醇防治小麦赤霉病施药时期及安全性评价

为了明确戊唑醇防治小麦赤霉病的关键施药时期及其安全性,进行了戊唑醇防治小麦赤霉病施用浓度和时期的田间试验。结果表明,25%戊唑醇EC在有效成分150g/hm2和75g/hm2两个施用剂量下对小麦赤霉病的防治效果没有显著差异,对病穗率和病情指数的防治效果分别为83.7%、86.0%和85.1%、88.5%;25%戊唑醇EC在有效成分150g/hm2施用剂量下在齐穗期到灌浆初期喷施对小麦安全,以盛花期施药对小麦赤霉病的防治效果最好,对病穗率和病情指数的防治效果分别为80.6%和84.1%,其次为齐穗期和初花期施药,对病穗率和病情指数的防治效果分别为53.9%、53.3%和54.6%、56.8%,灌浆初期施药的防治效果最差。     

Effect of some benzoylphenyl ureas onearias insulana eggs of different age

Diflubenzuron, PH 60–43, PH 60–45, penfluron(PH 60–44) and triflumuron were assayed by a dipping technique for their toxicity toEarias insulana (Boisd ) eggs of different age Testing at a screening concentration of 0 1% a 1 showed that diflubenzuron, triflumuron and PH 60–43 were highly active, whereas PH 60–44 and PH 60–45 were nearly inactive With triflumuron the mortality of 0-1-day-old eggs was >90% even at 0 005%, at 0 001% it was 50% In 1-2-day-old eggs, a >90% kill was obtained even at 0 0005%, whereas at 0 00025% it was 86% PH 60–43 was also highly active, at 0 01% the kill of 0-1-day-old eggs was >90% Again, this rate of kill was obtained with 1-2-day-old eggs at a still lower concentration, 0 005% Both compounds were inactive against 2-3-day-old eggs, even at 0 1%     

四种杀菌剂对金银花白粉病的防治效果及对金银花品质的影响

采用随机区组试验比较四种杀菌剂对金银花白粉病的防治效果，用高效液相色谱法测定各处理样品的绿原酸含量，以筛选出符合金银花规范化种植需要的药剂。结果表明，施药后14天以15％三唑酮600倍液防治效果最好，达77．8％，其次是15％三唑酮1200倍、50％多菌灵500倍液处理，防治效果分别为75．7％和70．8％，极显著地高于3％中生菌素500和1000倍及2％农抗1201000倍液处理的防效。2％农抗120500倍液的防治效果达60．3％，与前三种处理差异不显著，显著好于后三种处理，但未达极显著水平。15％三唑酮1200倍防治处理的绿原酸含量最高，达1．683％，其次是50％多菌灵500倍处理，绿原酸含量达1．539％，符合《中华人民共和国药典》要求，可作为金银花规范化管理中白粉病防治优先采用的药剂。     

樟巢螟滞育诱导特性的研究

为探求诱导樟巢螟(Orthaga achatina Butler)滞育的临界光周期及敏感虫态(期),在室内25℃和28℃下观察不同光周期对樟巢螟滞育的影响,并利用不同长光照和短光照组合对樟巢螟幼虫的不同龄期进行处理,掌握樟巢螟的敏感虫态(期)。结果表明光周期为L∥D=12.0h∥12.0h,L∥D=12.5h∥11.5h,L∥D=13.0h∥11.0h时,在25℃下,樟巢螟的滞育率分别为100%,94.80%和97.60%;在28℃下,滞育率分别为98.55%,99.05%和83.50%。当光周期为L∥D=13.5h∥10.5h,在25℃和28℃下,樟巢螟的滞育率分别为42.38%和34.05%。樟巢螟属长日照发育型昆虫,在25℃时诱导滞育的临界光周期是13.565h,在28℃时是13.364h。25℃时樟巢螟对光照反应最敏感的时期是4～5龄期,1～3龄次之,卵期最不敏感。     

Effectiveness of cyfluthrin dust treatment for control and protection of shelled maize against infestation by the larger grain borer,Prostephanus truncatus (Horn) (Coleoptera: Bostrichidae) in Tanzania

Abstract

Knockdown, mortality and residual activity of pyrethrins and cyfluthrin were studied on the larger grain borer (LGB), Prostephanus truncatus (Horn). Pyrethrum marc with 0.4% pyrethrins and cyfluthrin dust (0.1% a.i.) when applied on filter paper at 0.72 mg/cm² gave 98.6% and 100% knockdown (KD) respectively after 6 h. Cyfluthrin dust had a faster KD effect with 100% KD compared to 93.1% for pyrethrum marc, ½1/2>h after treatment. After 24 h there was no recovery from KD in both treatments. After 72 h, 23.2% of the LGB had recovered from KD while mortality was 76.8% in the pyrethrum marc treatment. After the same period, cyfluthrin resulted in 100% mortality. Mortality of P. truncatus exposed to different dosages of cyfluthrin dust in shelled maize was less than 100% at dosages lower than 1 part per million (ppm) but was 100% at 1 ppm and higher dosages 3 days after treatment. Progeny emergence was suppressed at all dosage levels above 0.25 ppm compared to a mean progeny of 68.8 in the check after 45 days. Cyfluthrin dust was more residually toxic at 0.5 ppm and higher dosages, with mortality of >90% at 5 months after treatment. This suggests that cyfluthrin dust at 0.1% a.i. mixed with shelled maize at 1 ppm will give protection and control of LGB infestation.     

内蒙古半干旱地区沙质过牧草地的沙漠化过程

为了掌握我国北方半干旱地区沙质放牧草地的沙漠化过程，在内蒙古东部的科尔沁沙地进行了为期5年的放牧试验。结果表明，在牧草利用率为70％的过牧条件下，草地植被盖度、高度、个体大小和根量急剧降低，第5年分别只有10.1％、1.0cm、2.5cm^3／株和18.7g/m^2（0－30cm土层内），是禁牧区的12.0％．3.02％．0.86％和22.1％。同时，家畜觅食活动增加，对草地践踏作用增强，如第5年其单位面积的蹄印6数和每只羊单位面积的蹄印数达到36.4n/m^2和8.5n/m^2，分别是轻牧区的9.6倍和8.25倍，土壤紧实度是禁牧区的3.75倍。植被盖度、高度、根量和植物个体普遍降低，家畜喜食植物首先从草地中退出后，草地开始出现小块裸斑，随着过牧的继续，这种裸斑迅速增加和扩大，使之相互连接成为大片裸地，如试验当年过牧区裸斑数仅为19个，而且73.7％≤2.5m的裸斑，到第3年裸斑数迅速增至358个，＞2.5m的裸斑比例从26.3％增加到31.3％，裸地率由1.8％增加到35.8％，第5年裸斑平均长度由2.4m增加到4.1m，＞2.6m的裸斑比例增至45.7％，裸地率达到了51.6％。当地面出现裸斑后，即使冬季不进行放牧，在风力的作用下草地中的裸地面积也会自然扩大，如第5年秋季过牧区的裸地率为51.6％，到第6年春季自然扩展到71.6％。裸地出现以后，冬春季在风力作用下地面迅速出现风蚀，过牧区第3年70％的测点发生风蚀，平均风蚀深度8.5cm，第5年90％的测点发生风蚀，平均风蚀深度25cm，最大风蚀深度90cm，地面呈现出凹凸不平的风沙地貌。研究结果表明，试验期间夏季放牧啃食对地表裸露的贡献率为41.3％，而冬春季节土壤风蚀对地表裸露的贡献率高达58.7％，这说明在内蒙古半干旱风沙区地表一旦裸露，马上就会因风蚀而迅速扩大。     

Influence of incubation-period humidity on the development of brown rot blossom blight of sour cherry

ABSTRACT When detached sour cherry (Prunus cerasus) blossoms were inoculated with conidia of Monilinia fructicola and subjected to a standard 8-h wetting treatment at 20 degrees C, blossom blight incidence was proportional to relative humidity (RH) when RH was held constant during the subsequent 6-day incubation period (frequency = 1.0 at the maximum RH of 92%; frequency = 0.38 at the minimum RH of 57%). Similarly, when a primary incubation period at 87% RH was followed by a secondary incubation period at 54% RH, blossom blight incidence was proportional to the number of hours at the higher level (frequencies of 0.94, 0.80, and 0.38 with primary incubation periods of 6 days, 36 h, and 12 h, respectively). When intact blossoms on potted trees were exposed to common inoculation and wetting treatments, disease incidence was consistently high on trees that subsequently were incubated in a controlled environment chamber (20 degrees C, 90 to 95% RH) but was extremely variable when trees were incubated under variable ambient conditions. Ambient incubation temperature had little effect on disease incidence 9 days after inoculation, whereas ambient RH had a pronounced effect: the frequency of blighted blossoms was 0.53 to 0.61 when the number of hours at RH >90% was approximately two to six times that at RH <60%, whereas this frequency was only 0.02 to 0.07 when the number of hours at RH >90% was approximately one-third the number at RH <60%. After 48 h at a constant RH of 89 or 57%, the water potential of excised uninoculated blossoms was -1.15 and -1.93 MPa, respectively; however, growth of M. fructicola on osmotically adjusted potato dextrose agar was unaffected by changes in water potential within this range. Thus, although RH during incubation has an important influence on blossom blight development, the causal mechanism remains uncertain.