【作者】 徐丹；

【导师】 董立尧；

【作者基本信息】 南京农业大学 ， 农业硕士（专业学位）， 2019， 硕士

【摘要】 野老鹳草(Geranium carolinianum)目前在我国小麦及油菜田发生十分普遍,在局部地区已经上升为恶性杂草,严重影响小麦和油菜的生长。因此,本文以野老鹳草为研究对象,对其种子生物学特性及在小麦田和油菜田的化学防除技术进行了初步研究。采用培养皿法和盆钵法研究了其种子的休眠特性及解除休眠方法、萌发及出苗特性;通过整株生物测定法测定了采自江苏省、河南省不同地区的7个野老鹳草种群对小麦田及油菜田常见除草剂的敏感性,初步检测野老鹳草是否已经产生抗药性;通过整株生物测定法测定了 54种可用于防除阔叶类杂草的除草剂对野老鹳草的室内毒力,并进行小麦和油菜的安全性测定,旨在筛选出对野老鹳草毒力高并且对作物安全的除草剂。对于小麦田以野老鹳草为优势种杂草群落的化学防除研究,本文根据除草剂单剂的室内筛选结果,选取两种新型复配剂嗪草酮·氟噻草胺及绿麦隆·环吡氟草酮,对小麦田5种优势杂草进行室内毒力测定,确定其田间适合的用药量。最后,为了响应国家“药肥双减”的号召,同时提高野老鹳草的化学防除效率,本文研究了3种表面活性剂类助剂对除草剂防除小麦田野老鹳草的增效减量作用,旨在找出可防除小麦田野老鹳草的除草剂助剂减量组合,为田间防治野老鹳草提供科学的理论依据。具体结果如下:本试验采用培养皿法和盆钵法研究了野老鹳草种子萌发和出苗适宜的条件,每天记录种子萌发数,计并以此计算种子萌发率、平均萌发时间(MGT)及萌发指数(GI)等来测定种子萌发情况。通过研究发现,野老鹳草具有较长的休眠期,新采集的野老鹳草种子在室温干储210 d后可以解除休眠,并且发现低温条件不利于野老鹳草种子休眠的解除。种子在10℃～25℃的恒温条件下萌发良好;有无光照及光周期的长短对种子的萌发无影响;对酸碱度不敏感,在pH值4～10范围内均能够萌发良好;对水势具有一定耐受力,抑制50%萌发率所需的水势为-0.42 MPa;盐分对野老鹳草种子的萌发具有一定抑制作用,当盐浓度达到160 mmol.L-1时,基本不能萌发;另外,种子在土壤垂直深度5 cm以内时仍然可以出苗,对播种深度适应性较强。采用整株生物测定法,通过测定七个地区野老鹳草种群对小麦田及油菜田常见除草剂的敏感性,来初步检测野老鹳草田间抗药性的发生情况;测定了 54种可用于防除阔叶类杂草的除草剂对野老鹳草的室内毒力;选取两种新型复配剂嗪草酮·氟噻草胺及绿麦隆·环吡氟草酮进行小麦田防除以野老鹳草为优势种杂草的杀草谱研究,结果如下:七个野老鹳草种群对5种供试药剂未产生抗药性;在此基础上,选取了 1个敏感的野老鹳草种群,采用整株生物测定的方法,对54种相关除草剂进行室内毒力的测定。同时研究了筛选出的对野老鹳草毒力强的其他作物田除草剂对小麦及油菜的安全性。结果表明:可以在小麦田用于防除野老鹳草的除草剂有:2甲4氯钠、噻吩磺隆、异丙隆、绿麦隆、灭草松、2,4-滴异辛酯6种茎叶处理剂和精异丙甲草胺、嘧苯胺磺隆(相对安全)、异丙隆3种土壤处理剂;可以在油菜田用于防除野老鹳草的除草剂有:精异丙甲草胺1种土壤处理剂;根据除草剂筛选结果,本研究选取两种新型复配剂进行小麦田以野老鹳草为优势种杂草的杀草谱研究,结果表明,嗪草酮·氟噻草胺复配剂按2:1的配比在300-360 g a.i./ha的剂量下、绿麦隆·环吡氟草酮按9:1的配比在675-900 ga.i./ha的剂量下,对小麦田野老鹳、猪殃殃、繁缕、菵草、日本看麦娘均有较好的鲜重防效。采用整株生物测定法测定了 Silwet 806等三种助剂对异丙隆等3种除草剂的增效作用及对小麦的安全性。结果发现:添加0.1%Silwet 806对除草剂异丙隆、2甲4氯钠增效作用较显著,可减量50%左右,对双草醚也有一定增效减量作用;添加150 mL/hm2安融乐对2甲4氯钠增效减量作用明显,GR90值降低至1182.51 ga.i/ha。对异丙隆及双草醚也有较好的增效减量作用,可以减少推荐剂量的50%以上;添加900 mL/hm2红太阳A8对异丙隆有明显的增效减量作用,GR90值降低至137.23 g a.i/ha,对2甲4氯钠及双草醚也有较好的增效减量作用,可以减少推荐剂量的50%以上。同时测定了除草剂与助剂混用对小麦安全性的影响结果发现:在异丙隆、2甲4氯钠及双草醚的推荐剂量及2倍推荐剂量下,与各助剂混用对小麦的鲜重均无显著性影响,对小麦安全。更多还原

【Abstract】 Geranium carolinianum is currently widespread in wheat and rape fields in China,and has risen to malignant weeds in some areas,seriously affecting the growth of wheat and rapeseed.In this paper we studied the seed biological characteristics including the dormancy characteristics,methods for releasing sleep,and germination characteristics of G.carolinianum seeds by petri dish method.the technique of chemical control using the in wheat and rape fields.The sensitivity of seven wild gGeranium populations from Jiangsu and Henan provinces to common herbicides in wheat fields and rape fields was determined by whole-plant bioassay.Clarified the resistance problem of wild gGeranium.And we determined the indoor virulence of 54 herbicides that can be used to control broadleaf weeds against E.carolinianum.Screening for the safety of wheat and rapeseed by herbicides with high toxicity to E.carolinianum.In order to prevent wild Geranium more effectively,according to the indoor screening results of herbicides,two new complex formulation,metribuzint flufenacet and chlortoluron huanbifucaotong were used to weed the wheat field weeds.Bioassay to determine the appropriate amount of medication that field.Finally,we studied three kinds of surfactant adjuvants synergistic reduction of herbicides on controlling the E.carolinianum in the wheat field.The aim is to find out the combination of herbicide and adjuvant that can control the E.carolinianum in the wheat field,and provide a scientific theoretical basis for the field control of E.carolinianum.The specific results are as follows:Seed germination and emergence experiments were carried out by using the petri dish method and the pot method.The germination rate was determined and the average seed germination time and germination index were calculated.Through research,it is found that the newly collected E.carolinianum seeds can be released from dormancy after being stored for 210 days at room temperature,and there is a long dormancy period,and low temperature can inhibit dormancy release.The optimum temperature for seed germination was 10℃～25℃;the germination process was not affected by light,and the effect of different photoperiod on seed germination was not significant;it was not sensitive to pH,and it germinated well in the range of pH 4～10;The water potential has some tolerance,and the water potential required to inhibit 50%germination rate is-0.42 MPa;the salt has a certain inhibitory effect on the germination of wild gGeranium seeds.When the salt concentration is 160 mmol·L-1,it can not germinate;It can be emerged when the vertical depth of the soil is less than 5 cm.Whole plant bioassay was used to detect the sensitivity of different 7 E.carolinianum populations to common herbicides in wheat fields and rape fields.The indoor virulence of 54 herbicides for controlling broadleaf weeds against wild Geranium was determined.Study on the herbicidal spectrum of two kinds of new complex formulation,metribuzint flufenacet and chlortoluron huanbifucaotong,and the control of weeds with E.carolinianum as the dominant species in wheat field.The specific results are as follows:7 E.carolinianum populations did not develop resistance to the 5 test herbicides.On this basis,a sensitive E.carolinianum population was selected,and the indoor virulence of 54 related herbicides was determined by whole bioassay.At the same time,the safety of other crop field herbicides with strong toxicity to E.carolinianum on wheat and rape was studied.The results showed that the herbicides that can be used to control wild gGeranium in wheat fields are:MCPA-sodium、thifensulfuron-methyl、isoproturon、bentazone、2,4-D-ethylhexyl 6 kinds of foliar-applied herbicides,and 3 soil-applied herbicides:s-metolachlor、orthosulfamuron(Relatively safe)、isoproturon.A soil-applied herbicide named S-metolachlor can be used in rapeseed fields to control herbicides of E.carolinianum.According to the results of herbicide screening,this study selected two new types of compounding agents to study the herbicidal spectrum of weeds with E.carolinianum as the dominant species in wheat field.The results showed that the metribuzint flufenacet compounding agent was in a ratio of 2:1 at a dose of 300-360 g a.i./ha,and the chlortoluron huanbifucaotong compounding agent in a ratio of 2:1 at a dose of 300-360g a.i/ha has good fresh weight control effect on wheat filed,E.carolinianum,Galium aparine var.tenerum,Stellaria media,Beckmannia syzigachne and Alopecurus japonicus.The Synergistic reduction of three adjuvants such as Silwet 806 on three herbicides such as isoproturon and the safety of wheat were determined by whole-plant bioassay.The results showed that the Synergistic reduction of adding 0.1%Silwet 806 on herbicide isoproturon and MCPA-sodium was significant.Can reduce the herbicide by about 50%.There are also some effects on bispyribac-sodiumc.The addition of 150mL/hm2 anngro has a significant effect on the synergistic reduction of MCPA-sodium,and the GR90 value is reduced to 1182.51 g a.i/ha.It also has a good synergistic effect on isoproturon and bispyribac,which can reduce the recommended dose by more than 50%.Adding 900mL/hm2 A8 has obvious synergistic effect on isoproturon,and the GR90 value is reduced to 137.23 g ai/ha.It also has good synergistic effect on MCPA-sodium and bispyribyl ether.Can reduce the recommended dose by more than 50%.At the same time,the effects of herbicides and adjuvants mixed on the safety of wheat were determined.The results showed that:the isoproturon MCPA-sodium and bispyribac at the recommended dose and 2 times the dose mixed with adjuvants has no significant effect on the safety to wheat.更多还原