淡紫拟青霉菌IPC菌株原生质体形成和再生条件

研究了菌龄、渗透压稳定剂、酶的种类及浓度、酶解时间和再生培养基等因素对淡紫拟青霉菌IPC菌株原生质体形成和再生的影响,结果表明,IPC菌株原生质体形成的最适宜条件为:菌龄20 h,用5 mg/mL蜗牛酶,0.8 mol/L NaCl的渗透压稳定剂,酶解2～3 h;原生质体涂布于含0.6 mol/L NaCl、0.5%琼脂的再生培养基上,再生率最高。     

淡紫拟青霉菌

理化性质：2亿孢子／克淡紫拟青霉菌粉剂的有效成分是淡紫拟青霉的活孢子．属活体微生物农药。淡紫拟青霉接种在PDA平板(或斜面)上，会长出扁平、淡紫色的特征菌落。在显微镜下观察拟青霉属的特征：分生孢子梗和分枝比青霉菌较分散，分孢子(梗孢子)成干燥的向基部的链，单胞、卵圆形到纺缍形、无色、腐生。2亿孢子／克淡紫拟青霉菌粉剂外观为可流动粉末，不应有结块。难溶于水，对光稳定，对水分、高温较敏感．活孢子在50℃情况下将失去活性。产品质量保证期为1年。     

淡紫拟青霉MCWA18菌株对南方根结线虫的寄生和防治作用

试用双温测定法,室内测定淡紫拟青霉ＭＣＷＡ１８菌株对南方根结线虫卵的寄生效果,测定结果表明,供试菌株对南方根结线虫卵的相对寄生率为９２．６％。在温室盆栽试验中,用剂量为５ｇ／ｍ２和１０ｇ／ｍ２固体菌剂处理,９３日后番茄根围土壤中南方根结线虫二龄幼虫的群体密度比对照分别降低６２．３％和６６．９％,番茄株高分别增加１７．２％和４９．６％,地上部鲜重分别增加１００％和１４５．９％,ＭＣＷＡ１８菌剂防病和促生效果均高于剂量为４．５ｇ／ｍ２益舒宝处理。     

淡紫拟青霉FZ-0289菌株对南方根结线虫卵寄生性的离体观测

 淡紫拟青霉(Paecilomyces lilacinus)FZ-0289菌株对南方根结线虫(Meloidogyne incognita)卵寄生性的体外测定表明,接种后7d,对胚胎发育期卵的寄生率为98.2%,对含幼虫卵寄生率为88.6%;卵囊接种14d后,卵囊内卵寄生率为94.5%。电镜观察可见菌丝在卵壳表面迅速匍匐蔓延生长,产生大量侵入结构,卵粒最终被菌丝包被,缢缩变形;菌株可在卵囊胶质物上蔓延生长并产生大量分生孢子梗及分生孢子。     

苹果蠹蛾不同防治方法的控害效应比较

为了及时地在苹果蠹蛾Cydia pomonella(L.)入侵地实施有效的防控策略,通过评价活雌蛾诱捕器诱捕雄蛾数量、在树干上化蛹或越冬的幼虫数量以及对苹果果实的为害程度,比较性信息素诱杀技术、迷向技术和化学防治技术对苹果蠹蛾的控害效应。结果显示,采用迷向法控制苹果蠹蛾的防治效果与化学防治相当,其中在第1代幼虫为害盛末期,蛀果率可控制在1%以下,在第2代幼虫为害盛末期,可控制在2%左右;而诱捕区与对照区(无处理)的蛀果率相当,几乎无控制效应。     

淡紫拟青霉次生代谢物质的抑菌效应

研究了淡紫拟青霉次生代谢物质不同浓度、不同培养时段、不同培养基培养对尖孢镰刀菌菌落生长与孢子萌发的抑制作用。结果表明：淡紫拟青霉次生代谢物质对尖孢镰刀菌的菌落生长与孢子萌发有显著的抑制作用；对菌丝生长的抑制率随浓度升高而升高，1％浓度处理，第7天的校正抑制率为42．78％，5％处理校正抑制率可达到80．56％；淡紫拟青霉的抑菌活性随培养时间的推延而上升，发酵后期（4～10天）抑菌活性较强，校正抑菌率均可达到70％以上。11天，菌液的活力又有所下降，校正抑菌率仅48．49％；不同培养基对淡紫拟青霉次生代谢物的抑菌活力有一定影响，察培克、PDA、盂加拉红的抑菌活力最高，对菌落的抑制率在72％左右，产孢抑制率达到90％以上。     

寄主植物对玫烟色拟青霉致病力的影响

通过比较茄子、黄瓜和节瓜三种寄主植物上烟粉虱的LC_(50)和LT_(50)值,评价了寄主植物对玫烟色拟青霉致病力的影响。烟粉虱的累计校正死亡率回归分析结果表明:在处理后的第8～14天,不同寄主植物上玫烟色拟青霉对烟粉虱的LC_(50)值差异显著;茄子、黄瓜和节瓜上烟粉虱的LC_(50)最小值出现的时间不同,分别在处理后的第14、10、12天。当玫烟色拟青霉的浓度为1．0×10~5和5．0×10~5分生孢子/mL时,黄瓜与茄子、节瓜上烟粉虱的LT_(50)值差异显著;当浓度为5．0×10~6～1．0×10~8分生孢子/mL时,三种寄主植物上烟粉虱的LT_(50)值差异不显著。     

蝉拟青霉固态培养条件筛选及优化

蝉拟青霉Paecilomyces cicadae是一种对鳞翅目Lepidoptera、膜翅目Hymenoptera等多种昆虫具有较强致病性的虫生真菌 [1-2].目前,对于蝉拟青霉固态发酵培养方法的报道较少 [3].为进一步开发利用该菌株,作者以一株分离自山蝉Cicada flammata若虫僵尸的蝉拟青霉LB菌株为对象,筛选并优化了固态培养基及培养条件.     

淡紫拟青霉对尖孢镰刀菌的拮抗作用与机制分析

研究表明淡紫拟青霉次生代谢物质对尖胞镰刀菌的孢子萌发与菌落生长有明显的抑制作用.淡紫拟青霉与镰刀菌活体间存在明显的营养竞争作用;淡紫拟青霉菌能产生细胞壁降解酶和蛋白或多糖性质的拮抗性物质;此活性物质存在于胞内和胞外,胞外物质和胞内提取液-1对尖胞镰刀菌孢子生成的抑制率在90%以上,粗蛋白提取液和粗多糖提取液的抑制率在73%左右,丙酮提取液抑制率最低,仅为25.42%;淡紫拟青霉抑菌活性物质主要存在于水相中;活性物质对温度耐受力较差,100℃或80℃处理30 min,基本失去活性.     

不同ET0计算方法在内蒙古东部地区适用性比较

内蒙古东部地区,土地资源丰富,但气象站点偏少,相关气象资料匮乏,应用FAO56 Penman-Monteith法计算ET0在多数地区相对困难。依据内蒙古东部地区典型气象站点(通辽气象站)1974—2013年40年气象资料,以FAO56 Penman-Monteith法作为标准,以FAO~(-1)7 Penman法、Hargreaves-Samani法、Priestley-Taylor法、Irmark-Allen拟合法分别对ET0进行计算,就其与FAO56 Penman-Monteith法的相关性进行分析。结果表明,Hargreaves-Samani法和Priestley-Taylor法的计算结果要明显高于FAO56 Penman-Monteith法计算所得的结果,不适合内蒙古东部地区应用;FAO~(-1)7 Penman法结果与FAO56 Penman-Monteith法相关性最好,但是4—9月份相对误差较大;Irmark-Allen拟合法结果最接近FAO56 Penman-Monteith法(相对误差19%,R20.92),计算简单且所需气象资料最少,更适宜内蒙古东部地区缺测气象条件下ET0的计算。     

蝉拟青霉不同来源菌株的生长特性及其对蚜虫的致病性

为了筛选到生防效果好的高效蝉拟青霉菌株,对其12个不同来源菌株的生长速率、产孢量、孢子萌发率、抗紫外线能力、耐热性以及对蚜虫的致病力等进行比较。结果表明,SL和3L菌株菌落生长最快,SL5和FY菌株产孢量最高,FY和3L菌株孢子萌发率最高,FY和FJS菌株抗紫外线能力最强,3L和3716菌株耐热性最强,LB、3L菌株和3716菌株对蚜虫的致病性高,孢子和代谢物对蚜虫的致死率都在80.00%以上。经综合比较,LB菌株在致病力、产孢量、抗紫外线、抗热性等方面表现优良。     

Changes induced by Trichoderma harzianum in suppressive compost controlling Fusarium wilt

The addition of species of Trichoderma to compost is a widespread technique used to control different plant diseases. The biological control activity of these species is mainly attributable to a combination of several mechanisms of action, which may affect the microbiota involved in the suppressiveness of compost. This study was therefore performed to determine the effect of inoculation of Trichoderma harzianum (T. harzianum) on compost, focusing on bacterial community structure (16S rRNA) and chitinase gene diversity. In addition, the ability of vineyard pruning waste compost, amended (GCTh) or not (GC) with T. harzianum, to suppress Fusarium wilt was evaluated. The addition of T. harzianum resulted in a high relative abundance of certain chitinolytic bacteria as well as in remarkable protection against Fusarium oxysporum comparable to that induced by compost GC. Moreover, variations in the abiotic characteristics of the media, such as pH, C, N and iron levels, were observed. Despite the lower diversity of chitinolytic bacteria found in GCTh, the high relative abundance of Streptomyces spp. may be involved in the suppressiveness of this growing media. The higher degree of compost suppressiveness achieved after the addition of T. harzianum may be due not only to its biocontrol ability, but also to changes promoted in both abiotic and biotic characteristics of the growing media.     

The bleaching induced by the phenylpyridazinone herbicide Metflurazon in Chlorella is a metabolic and reversible process

The treatment of synchronized cells of the green alga Chlorella fusca under photoautotrophic conditions with metflurazon (SAN H 6706; 4-chloro-5-dimethylamino-2-(α,α,α-trifluoro-m-tolyl-3(2H)-pyridazinone)) induces a bleaching process and results in white-appearing cells. This process of bleaching was followed by quantitative analysis of cell growth and cell division, photosynthetic oxygen evolution, respiratory oxygen consumption, and of pigment pattern at 0, 6, 12, 18, 24, 48, and 72 hr after incubation with different concentrations of metflurazon. Increasing concentrations of metflurazon gradually affected cell growth of Chlorella measured as increase in cell diameter. Cell division was inhibited completely with 1, 10, and 100 μM metflurazon. Photosynthetic oxygen evolution and respiratory oxygen consumption were not inhibited by 1 μM metflurazon during the first 6 hr; after this time a gradually increased inhibition was observed. Both parameters were inhibited by 100 μM metflurazon immediately after herbicide addition. A detailed analysis of the pigment content during the bleaching process revealed that: (a) The bleaching of Chlorella cells by metflurazon is not a simple photochemical process like the photobleaching of boiled cells, but is directed by the active metabolism of Chlorella itself. (b) The bleaching process is characterized by two phases: an accumulation of pigments followed by their degradation. The accumulation phase extends to 6 hr after herbicide addition. (c) During the accumulation phase, chlorophyll is accumulated to 380 and 106% in cells treated with 1 and 100 μM metflurazon, respectively, compared to the initial pigment content. The breakdown of chlorophyll, however, during the degradation phase is 5 times faster in the 1 μM treatment than in the 100 μM treatment. This difference resulted in the faster appearance of white cells with the low metflurazon concentration. (d) During the accumulation phase in the 1 μM treatment, the biosynthesis of chlorophylls, xanthophylls, and carotenes is inhibited by 56, 74, and 78%, respectively, when compared to a nontreated control. When related to the initial amounts, chlorophylls, xanthophylls, and carotenes are accumulated to 380, 230, and 153%, respectively. However, the synthesis of violaxanthin is specifically inhibited, followed by α-carotene. During the degradation phase, violaxanthin and α-carotene again, are the most rapidly disappearing pigments. Continuous culturing of white Chlorella cells resulted in a regeneration to green cells after 96, 240, 384 hr for 1, 10, and 100 μM metflurazone, respectively. The bleaching of Chlorella by metflurazon is evidently dependent on a functioning metabolism and is itself a regulated disassembly of the photosynthetic apparatus, which is reversible and not lethal.