不同除草剂对高粱田除草效果比较试验

试验研究38%莠去津、二甲戊灵2种除草剂对高粱品种"凤杂4号"的影响。结果表明,药剂处理的杂草数明显少于清水对照,38%莠去津325m L/667m2处理产生了轻微药害,植株比对照矮且苗小,而二甲戊灵390g/667m2处理的防效较好,且相对较安全。     

不同除草剂对高粱地杂草防除效果研究

本试验研究9种化学除草剂对‘济粱1号'播后苗前和苗后田间杂草防效、产量等性状的影响,筛选出既能有效防除杂草又能保证‘济粱1号'正常生长的除草剂。即:苗前单一除草剂50%异甲·莠去津悬乳剂200 m L(666.7m2用量,下同)和33%二甲戊灵150 m L封闭喷雾,苗后5—6叶期喷施单一除草剂75%氯吡嘧磺隆8 g和复配除草剂(56%二甲四氯27 m L+50%二氯喹啉酸10 g+38%莠去津79 m L+75%氯吡嘧磺隆2 g)均可用于高粱杂交种‘济粱1号'的杂草防治。     

黑河地区高粱田封闭处理除草剂筛选

为筛选出安全、有效的高粱田播后苗前土壤处理除草剂,以绥杂7号高粱为试验材料,采用随机区组试验比较了960 g·L~(-1)异丙甲草胺EC和38%莠去津SC两种除草剂及其混配制剂的除草效果和对高粱的安全性。结果表明:960 g·L~(-1)异丙甲草胺EC+38%莠去津SC(45.6 mL·667m~(-2)+115.2 mL·667 m~(-2))和38%莠去津SC 355 mL·667 m~(-2)对高粱田杂草防除效果好。综合考虑除草剂的防除效果和对后茬作物的影响,推荐使用960 g·L~(-1)异丙甲草胺EC+38%莠去津SC(45.6 mL·667 m~(-2)+115.2 mL·667 m~(-2))。     

不同除草剂对高粱地杂草防除效果

为探索防治高粱田杂草的适宜除草剂类型及其对高粱的安全性,采用田间小区试验,分别进行了4种播后苗前封闭除草剂和9种苗后除草剂对高粱田杂草的防除效果、高粱生长的安全性评价以及对高粱产量的影响研究。结果表明:播后苗前封闭处理的药剂为38%莠去津和二甲戊灵混合组合,使用剂量为(1995 g+1950 m L)/hm2,苗后茎叶处理的有效药剂有50%二氯喹啉酸450 g/hm2+50%氯氟吡氧乙酸异辛酯900 m L/hm2、10%乙羧氟草醚450 m L/hm2+50%乙草胺1350 m L/hm2、50%氯氟吡氧乙酸异辛酯900 m L/hm2+50%乙草胺1350m L/hm2,或单施10%乙羧氟草醚450 m L/hm2。以上5种药剂对高粱田杂草有很好的防除效果且对高粱生长安全,高粱产量也有显著提高。     

除草剂复配对海南高粱田杂草防除效果及安全性评价

[目的]探究不同除草剂复配对高粱田杂草防控效果和对高粱幼苗的损伤程度进行综合评价。[方法]采用5种除草剂处理在海南地区进行了杂草防效及对高粱幼苗安全性评价试验。[结果]莠去津、二氯喹啉酸、氯吡嘧磺隆复配(H1+H2+H3)和莠去津、二氯喹啉酸、氯吡嘧磺隆、二甲四氯(H1+H2+H3+H4)复配可综合防除禾本科、莎草科和阔叶科杂草,株数防效可达87%以上,干物重总防效均可达88%以上。同时这2种除草剂处理对幼苗损伤相对较小,伤苗率均低于10%,减少幼苗叶绿素和干物重的下降幅度,缓解杂草对高粱产量的影响。[结论]此2种除草剂处理可有效解决海南地区高粱田杂草为害问题,而莠去津、二氯喹啉酸、氯吡嘧磺隆复配(H1+H2+H3)节药减污,可作为海南高粱田杂草防除的重要技术参考。     

莠去津+敌草快防治高粱田杂草的安全性及除草效果

将38%莠去津悬浮剂与25%敌草快水剂混配使用，在高粱播后苗前进行土壤喷雾处理，调查其对高粱的安全性及除草效果。结果表明：莠去津+敌草快各剂量处理的高粱幼苗生长指标和产量与空白对照相比均无显著差异；施药后40 d,莠去津+敌草快的3个剂量处理对杂草的株数综合防效分别为88.9%、92.2%和95.0%,鲜重综合防效分别为91.0%、94.1%和97.3%,而对照药剂38%莠去津悬浮剂350 ml/667m²处理对杂草的株数和鲜重综合防效分别为80.8%和83.4%,莠去津+敌草快的3个剂量处理对杂草的株数和鲜重综合防效均显著高于对照药剂处理。可见，38%莠去津悬浮剂与25%敌草快水剂混配使用，在试验的剂量范围内对高粱安全，而且可以达到理想的防效，比莠去津单独使用显著提高了防效。     

两种除草剂混用对玉米田杂草的防治试验

田间小区试验表明,单用90%莠去津水分散粒剂对玉米田禾本科和阔叶草杂草的防效在92%以上,但对莎草科杂草香附子没有防效;而75%氯吡嘧磺隆水分散粒剂对香附子的防效为96%以上;两种除草剂混用对总草的防效在95%以上。在甜玉米苗后5々6叶期,667m2用75%氯吡嘧磺隆水分散粒剂2g~3g/667m2+90%莠去津水分散粒剂90g~100g/667m2兑水45L对香附子,马唐、牛筋草等禾本科杂草和繁穗苋、马齿苋等阔叶草等杂草的防效在95%以上;且供试药剂对作物安全无药害,对使用者安全无不适感和无不良反应。     

保护性耕作条件下苗后除草剂防除玉米田杂草试验

田间试验结果表明,保护性耕作条件下苗后除草剂在玉米3～5叶期、杂草2～4叶期施用4%烟嘧磺隆悬浮剂75和100 mL/667m 2,药后45 d总株防效分别为86.31%和93.50%,总鲜重防效为87.87%和94.72%,除草活性高于莠去津,尤其对禾本科杂草的鲜重防效均在91.38%以上。4%烟嘧磺隆50mL/667m 2+38%莠去津80 mL/667m 2混用后,对双子叶杂草除草效果有增效作用,株防效为92.47%,鲜种防效为94.02%。4%烟嘧磺隆50 mL/667m 2+72%2,4-D丁酯30 mL/667m 2混用后对双子叶杂草除草效果有增效作用,株防效为91.10%,鲜重防效为93.02%。40%福分悬浮剂350 mL/667m 2、400 mL/667m 2药后45 d的总株防效分别为89.80%和91.92%,总鲜重防效为90.54%和92.57%,除草剂活性高于莠去津,尤其对双子叶杂草鲜重的防效均在92.68%以上。     

复配除草剂对青海省玉米田杂草防除效果

选用5种复配除草剂进行玉米田杂草防除效果及安全性研究,筛选对玉米田杂草防效及安全性较好的除草剂。结果表明,20%烟嘧·莠去津OD 540 g/hm~2+288 g/L氯氟吡氧乙酸EC 129.6 g/hm~2+56%二甲四氯SP 252 g/hm~2复配组合,施药20 d对总阔叶草株防效为86.9%;施药40 d对总阔叶草株防效为90.6%;施药40 d对总阔叶草鲜重防效为95.6%。使用20%烟嘧·莠去津OD 540 g/hm~2+288 g/L氯氟吡氧乙酸EC+56%二甲四氯SP于玉米田苗后杂草2～4叶期进行茎叶喷雾处理,对玉米安全,除草效果良好,可以作为玉米田的主要除草剂进行使用。     

高粱除草药剂的筛选

针对高粱苗前苗后除草剂难以选择,缺少有效化学除草手段的现状,2010年在黑龙江省农业科学院绥化分院的管家科技园、郎家寨两处的试验地分别进行了高粱播后苗前封闭及苗后茎叶处理化学除草剂的筛选。结果表明:苗前使用异丙甲草胺+二甲戊灵封闭,对杂草的防效最高可达89.50%,对高粱出苗及生长无明显副作用;苗前使用异丙甲草胺+莠去津封闭,苗后使用莠去津对高粱无副作用,对杂草具有较好的抑制作用;苗后使用二氯喹啉酸或二甲.灭草松茎叶处理,对杂草的防效分别达86.40%和81.37%,对高粱生长无明显副作用。     

薏仁播后苗前和苗后除草剂的筛选

[目的]筛选适宜防治薏仁田杂草且对薏仁安全的除草剂。[方法]采用田间小区试验,研究了5种播后苗前封闭除草剂、4种苗后茎叶除草剂对薏仁田杂草防除效果和薏仁生长的安全性。[结果]播后苗前封闭防治杂草使用40%丁草胺·噁草酮乳油,使用剂量为2 000 m L/hm~2;苗后茎叶处理使用2.5%五氟磺草胺油悬浮剂,使用剂量为4 000 m L/hm~2。采用这2种药剂防治薏仁杂草效果明显且能保证薏仁安全生长。[结论]该试验结果为薏仁田杂草防控提供了参考。     

春玉米苗后如何防治鸭跖草

鸭跖草属寒温带发生危害严重杂草,2009年春玉米苗前施药期遇干旱天气,大多错过苗前防治机会,大家议论春玉米苗后化学防治鸭跖草困难,是否产生抗性？鸭跖草为一年生杂草,其种子可在深层土壤中存活多年,只要坚持轮作和深翻,很难产生抗药性。     

高粱田苗后除草剂安全性初步评估

为筛选出高效、安全的高粱苗后除草剂,本研究对用于高粱田的12种苗后除草剂在田间进行安全性评估,结果表明:硝磺草酮、炔草酸等7种除草剂对高粱药害较大,莠去津、二氯喹啉酸等5种除草剂对高粱生长没有影响或影响较小,初步明确这5种除草剂在高粱田的安全施药剂量。     

Activity of Corn Silk at Different Days after Silk Emergence

This study was carried out to evaluate the changes in silk activity of two corn cultivars Xundan 518 and Yongyou 618 after silk emergence. Artificial pollination was conducted at different days after silk emergence, and the ear length, ear diameter,barren tip length, 100-grain weight, grain number per ear and grain weight per ear were measured at harvest. The results showed that with the delay of pollination, the number and weight of grains per ear increased at first, peaked at D2 to D4, and decreased subsequently; ear diameter and 100-grain weight showed a downward trend. Correlation analysis revealed that grain number per ear and grain weight per ear were most closely correlated. Rapid silk extrusion and long-lasting silk activity proved that the two corn cultivars Xundan 518 and Yongyou 618 are tolerant to high temperature.     

洪涝淹水条件下杂交稻制种节瘟的发生与防治

1990-2002年，安仁县洪水淹过的杂交稻制种田发生三次节瘟灾害。调查发现，如果前期叶瘟未防治好，杂交稻制种时施用“九二0”后茎节伸长，遇洪涝淹水则叶鞘松动，容易发生节瘟，严重时间可减产70％以上。杂交稻制种节瘟防治的主要措施是：选地，择时，防洪防淹，防治好叶瘟。     

剑叶抽出后高温对杂交稻产量及其性状的影响

[目的]探究剑叶抽出后杂交水稻对高温的响应及耐热性。[方法]采用玻璃温室增温法,以感热指数为指标,研究了剑叶抽出后高温对8个杂交稻新组合产量及其性状的影响并评价耐热性。[结果]剑叶抽出后高温导致所有杂交稻品种实粒数、结实率、千粒重和单株产量明显减少,空粒数明显增加,而有效穗、成穗率、穗长、穗茎粗、一次枝梗、二次枝梗、总枝梗数、总粒数和着粒密度的增减因组合而异。千粒重的感热指数与抗热系数呈显著相关,可作为剑叶抽出后水稻抗热性评价的可靠指标在生产实践中应用。性状感热指数的聚类分析显示,茶优99082、03A／999046、振优99082和跃丰6A／R225具有强抗热性,Ⅱ优551、天丰优551和Ⅱ优225具有中抗热性,Ⅱ优50329具有感热性。[结论]该研究可为参试各品种的推广应用提供理论依据。     

几种除草剂对纤维高粱苗后杂草防治效果研究

为探讨纤维高粱出苗后杂草化学防除的有效方法。通过田间试验,研究了5种化学除草药剂的田间防治效果。结果表明:防除纤维高粱田一年生阔叶杂草的苗后茎叶处理除草剂选用72%2,4-滴丁酯乳油、48%灭草松水剂或56%2甲4氯钠可溶粉剂较适宜;防除纤维高粱田一年生禾本科杂草选用50%二氯喹啉酸可湿性粉剂较适宜;同时防除一年生禾本科及阔叶杂草可选用38%莠去津悬浮剂或48%灭草松水剂+50%二氯喹啉酸可湿性粉剂。     

Spore Germination and Emergence of Bacillus megaterium

Bacillus megaterium spores have a characteristic polar knob and equatorial ridge, or groove. During germination, the spore case appears to split along this ridge, and thus allows the new cell to emerge. Mechanically ground spores also split along this ridge, one part of the spore case being hinged to the other, the ridge being evident along a free edge. The equatorial ridge appears to be an area of suspectibility to mechanical pressures and, perhaps, in normal germination, to enzymic action as well.     

Spectral Detection of Emergence in Corn and Cotton

Multispectral reflectance of emerging cotton (Gossypium hirsutum) and corn (Zeamays) seedlings was measured during the 2000 and 2001 growing seasons. Reflectance in blue, green, red, and near infrared (NIR) wave lengths was used to detect seedling emergence, to monitor leaf area growth, and to measure the effect of bare soil reflectance on scene (bare soil and seedlings) reflectance. Cotton and corn seedlings were detected 1 day after initial emergence (1 DAE) in 2000 by the red band. The red band detected seedlings in 2001 at 9 and 8 DAE in early and late planted corn, respectively, and on 0 DAE for cotton. The normalized difference vegetative index (NDVI) detected seedlings at 1 DAE or 2 DAE in both years. Seedling ground cover in 2000 on the initial detection date in the target areas averaged 1.3% and 0.9%, respectively, for cotton and corn; comparable values in 2001 for cotton, early planted corn, and late planted corn, were 1.4%, 0.4%, and 0.8%, respectively. The red wave band was the most sensitive single band for detecting the presence of seedlings, but NDVI was the most sensitive spectral indicator, which was apparently due to the red band since the NIR band did not always detect seedlings. Seedling leaf area was linearly correlated with NDVI values beginning at 1 or 2 DAE. Bare soil was the major component of the scene during stand establishment and dominated single band reflectance and NDVI values. A dry soil surface that was smoothed and sealed by rain usually caused single band reflectance to increase. The high variability in spectral characteristics of bare soil restricted the interpretation of the spectral data to concluding whether or not seedlings were emerging, but without estimating numbers and seedling size.