Pendimethalin 二甲戊乐灵

二甲戊灵

基本信息

二甲戊灵（也称为二甲戊乐灵）
英文名称：Pendimethalin

甲戊乐灵
一种优秀的旱田作物选择性除草剂，可以广泛应用于玉米、大豆、花生、棉花、直播旱稻、马铃薯、烟草、蔬菜等多种作物田除草。目前，二甲戊灵是世界第3大除草剂，销售额仅次于灭生性除草剂草甘膦、百草枯，也是世界上销售额最大的选择性除草剂。
其它名称：施田补、二甲戊乐灵。
CAS号：40487-42-1。
分子式：C13H19N3O4。
分子质量:281.31。
中文名称：N-(1-乙基丙基)-2,6-二硝基-3,4-二甲基苯胺；菜草灵；施田补；胺硝草；二甲戊乐灵；N-(1-乙基丙基)-3,4-二甲基-2,6-二硝基苯胺。

理化性质
纯品为桔黄色结晶固体，熔点54-58℃，溶解度25℃，水中0.275mg/L，易溶于丙酮、二甲苯等有机溶剂。

动物毒性
对人畜低毒。大鼠急性口服LD50为1050-1250毫克/公斤，兔经皮LD50>5000毫克/公斤，对鸟类、蜜蜂低毒。

常用剂型
33%二甲戊灵乳油。

适用作物
棉花、玉米、直播旱稻、大豆、花生、马铃薯、大蒜、甘蓝、白菜、韭菜、葱、姜等多种旱田及水稻旱育秧田。

防除对象
一年生禾本科杂草、部分阔叶杂草和莎草。如：稗草、马唐、狗尾草、千金子、牛筋草、马齿苋、苋、藜、苘麻、龙葵、碎米莎草、异型莎草等。对禾本科杂草的防除效果优于阔叶杂草，对多年生杂草效果差。

作用机理
二甲戊灵为选择性芽前、芽后旱田土壤处理除草剂。杂草通过正在萌发的幼芽吸收药剂，进入植物体内的药剂与微管蛋白结合，抑制植物细胞的有丝分裂，从而造成杂草死亡。

使用方法
旱稻，水稻旱育秧田：每亩用33%二甲戊灵乳油150-200毫升，兑水15-20千克，播种后出苗前表土喷雾。
直播棉花每亩用33%二甲戊灵乳油150-200毫升，兑水15-20千克，播种前或播种后出苗前表土喷雾。因北方棉区天气干旱，为了保证除草效果，施药后需混土3-5厘米。
玉米：（1）东北地区春玉米每亩用33%二甲戊灵乳油200-300毫升，兑水15-20千克，播种后出苗前表土喷雾。施药应在播种后5天内进行，施药过晚容易对玉米产生药害。（2）夏玉米每亩用33%二甲戊灵乳油150-200毫升，兑水15-20千克，播种后出苗前表土喷雾。华北地区免耕播种的夏玉米，播种后先浇蒙头水，浇水后2天内施药，施药过晚易产生药害。
大豆、花生：（1）春大豆、春花生，每亩用33%二甲戊灵乳油200-300毫升，兑水15-20千克，整地后施药混土，然后播种。（2）夏大豆、夏花生，每亩用33%二甲戊灵乳油150-200毫升，兑水15-20千克，播种后1-2天表土喷雾，施药过晚易产生药害。
马铃薯：亩用33%二甲戊灵乳油150-200毫升，兑水15-20千克，播种后出苗前表土喷雾。
直播蔬菜田：大蒜、姜、胡萝卜、辣椒、韭菜、小葱、洋葱、芹菜、芫荽等直播田，亩用33%二甲戊灵乳油100-150毫升，兑水15-20千克，播种覆土后，表土喷雾。
移栽蔬菜田：辣椒、西红柿、韭菜、大葱、洋葱、芹菜、菜花、白菜、甘蓝、茄子等移栽田，亩用33%二甲戊灵乳油100-150毫升，兑水15-20千克，移栽前1-2天表土喷雾。
油菜田：（1）直播油菜田，亩用33%二甲戊灵乳油100-150毫升，兑水15-20千克，播种覆土后，表土喷雾；（2）移栽油菜田，亩用33%二甲戊灵乳油150-200毫升，兑水15-20千克，移栽前1-2天表土喷雾。
韭菜：老韭菜在收割伤口愈合后，亩用33%二甲戊灵乳油100-150毫升，兑水15-20千克，均匀喷雾。

注意事项
1．土壤有机质含量低、沙质土、低洼地等用低剂量，土壤有机质含量高、粘质土、气候干旱、土壤含水量低等用高剂量。
2．土壤墒情不足或干旱气候条件下，用药后需混土3-5厘米。
3．甜瓜、甜菜、西瓜、菠菜等作物对本品敏感，容易产生药害，不得在这些作物上使用本品。
4．本品在土壤中的吸附性强，不会被淋溶到土壤深层，施药后遇雨不仅不会影响除草效果，而且可以提高除草效果，不必重喷。
5．本品在土壤中的持效期为45-60天。

pendimethalin
Herbicide
HRAC K1 WSSA 3; dinitroaniline

NOMENCLATURE
Common name pendimethalin (BSI, E-ISO, ANSI, WSSA); pendiméthaline ((f) F-ISO); penoxalin* (former WSSA name)
IUPAC name N-(1-ethylpropyl)-2,6-dinitro-3,4-xylidine
Chemical Abstracts name N-(1-ethylpropyl)-3,4-dimethyl-2,6-dinitrobenzenamine
CAS RN [40487-42-1] EEC no. 254-938-2 Development codes AC 92 553 (Cyanamid)

PHYSICAL CHEMISTRY
Composition Tech. grade is 90% pure. Mol. wt. 281.3 M.f. C13H19N3O4 Form Orange-yellow crystals. M.p. 54-58 ºC B.p. Decomposes on distillation. V.p. 1.94 mPa (25 ºC) KOW logP = 5.2 S.g./density 1.19 at 25 ºC Solubility In water 0.33 mg/l (20 ºC). In acetone 800, xylene >800, hexane 48.98, dichloromethane >800, (all in g/l, 20 ºC). Readily soluble in benzene, toluene, and chloroform. Slightly soluble in petroleum ether and petrol. Stability Very stable in storage; store above 5 ºC and below 130 ºC. Stable to acids and alkalis. Slowly decomposed by light. DT50 in water <21 d.

COMMERCIALISATION
History Herbicide reported by P. L. Sprankle (Proc. Br. Weed Control Conf., 12th, 1974, 2, 825). Introduced by American Cyanamid Co. (now BASF AG). Patents BE 816837; US 4199669 Manufacturers BASF; Feinchemie Schwebda; Rallis; Sundat

APPLICATIONS
Biochemistry Microtubule assembly inhibition. Mode of action Selective herbicide, absorbed by the roots and leaves. Affected plants die shortly after germination or following emergence from the soil. Uses Control of most annual grasses and many annual broad-leaved weeds, at 0.6-2.4 kg/ha, in cereals, onions, leeks, garlic, fennel, maize, sorghum, rice, soya beans, peanuts, brassicas, carrots, celery, black salsify, peas, field beans, lupins, evening primrose, tulips, potatoes, cotton, hops, pome fruit, stone fruit, berry fruit (including strawberries), citrus fruit, lettuce, aubergines, capsicums, established turf, and in transplanted tomatoes, sunflowers, and tobacco. Applied pre-plant incorporated, pre-emergence, pre-transplanting, or early post-emergence. Also used for control of suckers in tobacco. Phytotoxicity Injury to maize may occur if used as a pre-plant, soil-incorporated treatment. Formulation types EC; GR; SC; WG. Selected products: 'Herbadox' (BASF); 'Prowl' (BASF); 'Stomp' (BASF); 'Mopup' (Crop Health); 'Pressto' (Cequisa); 'Tremor' (Barclay)

OTHER PRODUCTS
'Claymore' (BASF); 'Go-Go-San' (BASF, Kumiai); 'Pendulum' (BASF); 'Pentagon' (BASF); 'Ipimethalin-L' (Dintec); 'Pendimax' (Dow AgroSciences); 'Repose' (Cedar); 'Tata Panida' (Rallis); 'Valeran' (IQV) mixtures: 'Celtic' (+ picolinafen) (BASF); 'Chacal' (+ imazamethabenz-methyl) (BASF); 'Chekway' (+ imazaquin-ammonium) (BASF); 'Crystal' (+ flufenacet) (BASF); 'Elite' (+ imazethapyr) (BASF); 'Encore' (+ isoproturon) (BASF); 'Impuls' (+ bentazone) (BASF); 'Indiana' (+ metolachlor) (BASF); 'Jolt' (+ isoproturon) (BASF); 'Malibu Pack' (+ flufenacet) (BASF); 'Megaplus' (+ imazamethabenz-methyl) (BASF); 'Merit' (+ simazine) (BASF); 'Nirvana' (+ imazamox) (France) (BASF); 'PicoPro' (+ picolinafen) (BASF); 'Pursuit Plus' (+ imazethapyr) (BASF); 'Squadron' (+ imazaquin-ammonium) (BASF); 'Steel' (+ imazaquin+ imazethapyr) (BASF); 'Treplik Duo' (+ neburon) (BASF); 'Trump' (+ isoproturon) (BASF); 'Bullet' (+ cyanazine) (Feinchemie Schwebda); 'Comboral' (+ trifluralin) (Dow AgroSciences); 'Galaxy' (+ clomazone) (FMC); 'Pendanil' (+ propanil) (Crystal); 'Preclaim' (+ fenoxaprop-P-ethyl) (Bayer CropScience) Discontinued products: 'Sovereign' * (Novartis) mixtures: 'Activus' * (+ cyanazine) (Cyanamid); 'Monarch' * (+ prometryn) (Cyanamid); 'Oklahoma' * (+ imazamox) (BASF); 'Structure' * (+ imazaquin+ imazethapyr) (BASF); 'Totem' * (+ chlorotoluron) (Cyanamid); 'Primafit' * (+ terbuthylazine) (Novartis)

ANALYSIS
Product analysis by glc with FID (J. C. Wyckoff, Anal. Methods Pestic. Plant Growth Regul., 1978, 10, 461). Residues of the 4-hydroxymethyl analogue (after formation of a derivative) and of pendimethalin determined by glc with ECD (idem, ibid.).

MAMMALIAN TOXICOLOGY
Oral Acute oral LD50 for rats >5000, male mice 1620, female mice 1340, rabbits >5000, beagle dogs >5000 mg/kg. Skin and eye Acute percutaneous LD50 for rabbits >2000 mg/kg. Non-irritating to skin and eyes (rabbits). Inhalation LC50 for rats >320 mg/l. NOEL In 2 y feeding trials, rats receiving 100 mg/kg diet showed no ill-effects. Water GV 20 mg/l (TDI 5 mg/kg b.w.). Toxicity class WHO (a.i.) III; EPA (formulation) III EC classification R43| N; R50, R53

ECOTOXICOLOGY
Birds Acute LD50 for mallard ducks 1421 mg/kg b.w. Dietary LC50 (8 d) for bobwhite quail 4187 mg/kg. Fish LC50 (96 h) for rainbow trout 0.14, bluegill sunfish 0.2, channel catfish 0.42 mg/l. Daphnia EC50 (48 h) 0.28 mg/l. Bees LD50 (topical) >101.2 mg/bee.

ENVIRONMENTAL FATE
Animals In rats, the major metabolic routes for pendimethalin involve hydroxylation of the 4-methyl and N-1-ethyl groups, oxidation of these alkyl groups to carboxylic acids, nitro-reduction, cyclisation and conjugation (J. Zulian, J. Agric. Food Chem., 1990, 38, 1743). Plants In plants, the 4-methyl group on the benzene ring is oxidised to the carboxylic acid via the alcohol. The amino nitrogen is also oxidised. At harvest time, residues in crops are below the validated sensitivity of the analytical method (0.05 ppm). Soil/Environment In soil, the 4-methyl group on the benzene ring is oxidised to the carboxylic acid via the alcohol; the amino nitrogen is also oxidised. DT50 in soil is 3-4 mo (A. Walker & W. Bond, Pestic. Sci., 1977, 8, 359). Kd ranges from 2.23 (0.01% o.m., pH 6.6) to 1638 (16.9% o.m., pH 6.8) (H. J. Pedersen et al., Pestic. Sci., 1995, 44, 131).