XMG-35真空熏蒸库

XMG-35熏蒸库具有常压熏蒸、熏蒸气体重复利用等功能.熏蒸库有良好的密封效果,20Kpa的压力下,24th后压力增加5%~15%.泵系统功能强大,5min可减压30%,35min可减压75%,并可以使至少70%的熏蒸剂得到重复利用.在减压熏蒸过程中,可控制库内温度,循环系统可保持熏蒸库内熏蒸剂均匀分布,并具有独特的装置,能用普通的热导式卤素分析仪准确地检测熏蒸库内熏蒸剂的浓度.     

土壤真菌对威百亩熏蒸的响应特征

为探明土壤熏蒸后真菌群落的演变特征及其种间关系的变化规律,以揭示熏蒸剂对土壤生态系统的利害关系。选取威百亩作为典型熏蒸剂对连作3年黄瓜的土壤进行熏蒸处理,并采用高通量测序手段检测了各处理在不同时段的真菌群落。与未熏蒸对照处理(NM)相比,Chao1指数在低浓度(LM,50 mg·kg-1)和高浓度威百亩熏蒸处理(HM,100 mg·kg-1)中分别降低了14%(P=0.001)和16%(P=0.005),各处理真菌群落结构的差异也达显著水平。供试土壤中潜在典型病原真菌主要为Gibberella和Fusarium,且受到威百亩熏蒸的显著抑制,尤其在HM处理中,其丰度较NM处理分别降低了95%和53%(P0.05)。而潜在典型有益菌如Talaromyces和Arthrographis展现出与潜在病原菌相反的趋势,且这种趋势在HM处理中更明显。随着培养时间延长,虽然Gibberella和Fusarium在LM处理中展现出抑制-恢复的趋势,但在HM处理中其丰度随时间逐渐降低。Network关联分析结果显示,在NM处理中各功能菌丰度间均为正相关关系,而高浓度威百亩熏蒸后出现了优势菌对潜在病原菌的拮抗作用。综上所述,相比于低浓度威百亩熏蒸,高浓度威百亩不仅有效抑制了土壤中潜在病原真菌的活性,而且还通过调控真菌群落种间关系从而强化了优势菌对潜在病原真菌的拮抗作用,进而间接地增强了部分有益菌的活性。     

完全不渗透膜对熏蒸剂大气散发的控制效果

为明确完全不透性膜(totally impermeable film,TIF)对熏蒸剂在田间应用时散发和残留的影响,采用静态散发箱技术测定了TIF与聚乙烯膜(polythene film,PE)对氯化苦、1,3-二氯丙烯(1,3-dichloropropene,1,3-D)和棉隆施用后所产生的异硫氰酸甲酯(methyl isothiocyanate,MITC)大气散发的控制效果,并应用气相色谱法检测了揭膜后3种熏蒸剂在土壤中的残留情况。结果表明,在20 g/m~2(棉隆为15 g/m~2)剂量下,氯化苦、1,3-D及MITC透过PE的累积散发率为施用量的6.42%、7.37%和22.27%,透过TIF的累积散发率为施用量的0、0.65%和2.05%,表明TIF极大地降低了熏蒸剂向大气的散发量,可有效控制熏蒸剂向大气扩散。揭膜后氯化苦及1,3-D在各处理土壤中的残留量均低于0.30 mg/kg,说明TIF没有增加土壤中氯化苦和1,3-D的残留量;但MITC(15 g/m~2)在TIF下10~20 cm土壤中的残留量在3.28~3.41 mg/kg之间,高于在PE下的残留量(0.46~0.47 mg/kg),表明TIF能提高MITC在土壤中的持效浓度。     

Evaluation of chemical and integrated strategies as alternatives to methyl bromide for the control of root-knot nematodes in Greece

Current environmental awareness has led to a greater demand for alternative nematode control strategies. Three field experiments were established to compare management tactics on cucumber in commercial greenhouses naturally infested with root-knot nematodes (Meloidogyne spp). Cucumber rootstocks which have shown resistance to soil-borne diseases were tested to reveal any resistance/tolerance to root-knot nematodes, and integration of these rootstocks with nematicides was investigated. Metham-sodium and 1,3-dichloropropene (1,3-D) provided good control of nematode populations when their application was followed by the application of a non-fumigant nematicide such as cadusafos or oxamyl. Neither fumigant could provide season-long control of nematode populations, and a further application of cadusafos was required for satisfactory control. The efficacy of metham-sodium was significantly increased when injected into soil in comparison with its application through the drip irrigation system. The use of rootstocks resistant to soil-borne fungal pathogens used together with chemical means of nematode control provided promising results for their further use in integrated strategies as alternatives to methyl bromide. However, the latter was the superior treatment for the control of root-knot nematodes in soil infested with residues of galled roots. Dazomet, metham-sodium nor the non-fumigant nematicides oxamyl and fenamiphos could reduce nematode population as efficiently as methyl bromide. None of the chemicals tested except methyl bromide could enter galled roots and kill surviving nematodes.     

应用13％多·硫烟剂防治云杉落针病试验

通过采用13％多·硫烟剂对云杉落针病进行防治试验,结果表明：13％多·硫烟剂防治云杉落针病的适宜用药量为15kg/hm^2,5月下旬至6月中下旬为防治最佳时机,防治2次最为理想,防治效果可达65％以上,并对人畜无害和云杉生态安全,可在林区大面积推广应用。     

不同土壤熏蒸剂防除烤烟苗床杂草试验

[目的]筛选高效低毒低价位的土壤熏蒸剂。[方法]以烟草品种K326为供试材料,研究了斯美地水剂等4种药剂防除烟草苗床期杂草的效果。[结果]35%线克水剂、32.7%田土净水剂3、2.7%斯美地水剂、溴甲烷4种药剂对烟草苗床期杂草均有较好的防除效果,能有效地防除禾本科、蓼科、苋科、鸭跖草科、菊科等烟草苗期主要杂草;对苗床期次要杂草石竹科、茜草科、豆科等的防效高达100%。其中,35%线克水剂和32.7%斯美地水剂的防效最好。但参试药剂处理对次要杂草莎草科的香附子和禾本科的狗牙根的防除效果相对较差。[结论]各药剂处理对烟草苗床期的主要杂草均有较好的防除效果,且对烟苗的生长无不良影响。     

Physical, chemical and environmental properties of selected chemical alternatives for the pre-plant use of methyl bromide as soil fumigant

Production and use of methyl bromide, a soil fumigant, are being restricted because of this chemical's deleterious effects on stratospheric ozone concentrations. Several products, some of which are currently used as soil fumigants, are being considered as possible replacements for methyl bromide, alone and in various combinations. Among these, 1,3-dichloropropene, methyl isothiocyanate generators such as metam-sodium, and chloropicrin are currently registered, while others such as methyl iodide and sodium azide are at different stages of the registration process. This review examines physicochemical properties, environmental fate, and metabolism of the various potential methyl bromide replacement products.     

冬枣贮藏病害防治技术

对冬枣贮藏期间主要病害种类的防治技术研究结果表明,对冬枣贮藏期间危害最为严重的浆胞病、霉腐病等病害,最佳防治药剂为DZ熏杀剂,最佳熏蒸浓度为7倍,熏蒸次数为3次。