南开除草活性测定方法

除草活性测定方法

南开方法：

汉语文献来源：

任康太,宋洪海,杨秀凤等.3-烷氧基-6-取代苯氧基哒嗪的合成及其除草活性的构效关系[J].高等学校化学学报.2000,21(12)：1840-1843.

P I50测定

根据所设定的药剂处理浓度, 称取各待测样品, 用DM F 溶解后再用蒸馏水定容, 配制成乳剂，在50 mL 小烧杯的底部放一张直径4 cm 的滤纸片, 吸取预先配制好的待测药液5 mL , 加入小杯内, 选取萌发稗草种子10 粒均匀播种在滤纸片上, 将其置于28 ℃恒温光室

中培养, 72 h 后测量稗草株高, 与用蒸馏水处理的对照相比较计算株高抑制百分数, 取3 次测试结果的平均值, 按线性回归方程y = a+ bx 计算化合物抑制50% 的摩尔浓度( IC50) 和p I50 (～lg IC50) 值。

盆栽除草活性测试

在装有过筛土壤的塑料盆中, 定量播种稗草、马唐、油菜、苋菜种子, 复土后在自然光照条件下, 温室培养. 按1. 5 kg.g.i/h a (有效成份) 的用药量分别称取各供试样品, 用溶剂溶解后加水配成乳剂, 于植物播种后出苗前进行土壤和茎叶处理. 每处理重复2次, 随机排列. 药剂处理后12 d 测量每种植物地上部分的鲜重, 与不施药对照比较, 以鲜重减少百分数作为评价药效指标。

英文文献来源：

W.Q M,S.K H,C.H Y,etal. Synthesis and Herbicidal Activity of

2-Cyano-3-substituted-pyridinemethylaminoacrylates[J].Journal of Agricultural and Food Chemistry.2003,51:5030-5035.

Plant Material. （原材料）

The three broadleaf species used to test the herbicidal activity of compounds were alfalfa (Medicago sativa L. 苜蓿), rape (B.napus 油菜), and amaranth pigweed (Amaranthus retroflexus反枝苋). Seeds of A.retroflexus were reproduced outdoors and stored at room temperature.Seeds of alfalfa and rape were bought from the Institute of Crop, Tianjin Agriculture Science Academy.

Culture Method. （培养方法）

Seeds were planted in 6 cm diameter plastic boxes containing artificial mixed soil. Before plant emergence, the boxes were covered with plastic film to keep moist. Plants were grown in the greenhouse. Fresh weight of the above ground tissues was measured 10 days after treatment. The inhibition percent was used to describe the control efficiency of the compounds.

Treatment. （处理）

The dosage (activity ingredient) for each compound was 1.5 kg/ha

（0.1kg/mu;150mg/m2）. Purified compounds were dissolved in 100 μL of N,N-dimethylformamide(DMF) with the addition of a little Tween 20 and were then sprayed using a laboratory belt sprayer delivering a 750

L/ha (50L/mu;75ml/m2)spray volume. The mixture of the same amount of water,N,N-dimethylformamide,and Tween 20 was sprayed as control. Preemergence Treatment.苗前处理

Compounds were sprayed immediately after seed plantings. There were two replicates for each treatment.

Postemergence Treatment.苗后处理

Compounds were sprayed after the first true leaf expanded.

西农方法：

徐冉、吴文君等的种子萌发法并略加改动。在直径9 cm 培养皿中加入提取1mL (对照加丙酮1 mL)和9mL蒸馏水, 混合均匀, 使提取物浓度达100mg/ mL- 1, 盖上2层滤纸。然后将10粒作物种子(高粱和油菜种子使用前催芽24 h)水平摆成1行。所有处理均重复3次, 于( 26 ±1) ℃恒温箱中黑暗培养, （4天）96 h后(高粱和油菜种子培养72 h （3天）)分别测量作物幼苗的根长(小麦测量最长根)和茎长, 按下式计算抑制率。抑制率= 〔(对照根或茎生长长度- 处理根或茎生长长度) /对照根或茎生长长度〕×100%

选取在100 mg/ mL- 1浓度下对4种作物种子具有突出抑制率的不同溶剂提取物, 用丙酮将其稀释至50、25、12. 5、6. 25和3. 125 mg/ mL- 1, 然后按照上述方法进一步研究不同浓度提取物对供试作物幼苗生长的抑制作用。

参考文献：

徐冉, 续荣治. 用荞麦秸秆粉防除杂草的初步研究[ J] . 植物保护,