葡萄拟尾孢菌培养特性的研究

经不同培养基培养比较 ,在葡萄叶煎汁培养基上葡萄拟尾孢菌生长最旺盛 ,在CA培养基上产孢量最多。菌丝生长和产孢适宜温度为 20～30℃ ,最适为 25℃ ,低于5℃或高于 40℃病菌停止生长和产孢。菌丝生长、产孢的适宜pH为 6～8,最适 pH 7。在室外自然光照射下菌落生长量最小 ,但产孢量最多 ,室内连续光照有利于菌丝生长。病菌对碳源的利用 ,以可溶性淀粉、乳糖对菌落发育最好 ,山梨糖最差 ;菌丝干重以葡萄糖和可溶性淀粉最好 ,山梨糖最差 ;产孢以菊糖最好。对氮源的利用 ,以硝酸钙为好 ,对尿素的利用能力最差 ,不能利用亚硝酸钠 ;产孢以白氨酸最好 ,菌丝干重以丙氨酸和天冬氨酸最好     

山茶花灰斑病菌生物学特性研究

 山茶花(Camellia japonica L.)灰斑病菌[Pestalotiopsis guepini (Desm.) Stey.]^[1,2,3,4]菌丝生长适温20-25℃,适宜pH值是5-7。在不同培养基里以PDA和燕麦培养基最佳。对碳源的利用以葡萄糖,蔗糖最佳,木糖最差,氮源以门冬酰胺、蛋白胨、酵母液最佳,尿素最差。
分生孢子萌发适温20-25℃,适宜pH值是4-5,在不同营养液里以酵母汁,茶花叶汁萌发最好。在不同光照条件下,自然光和连续黑光灯利于产孢,完全黑暗不产孢。不同培养基里以燕麦和PDA培养基最适宜病菌产孢,在山茶花叶汁与水洋菜培养基里不产孢。     

淡紫拟青霉NH-PL-03菌株在不同培养基上的生长特性

观察淡紫拟青霉菌在不同培养基上的生长状况,研究淡紫拟青霉菌在不同培养基上的生长特性及对茎线虫的毒力。结果表明:不同培养基对淡紫拟青霉NH-PL-03菌株的生长特性有明显影响。在孟加拉红、PDA和察氏培养基上,菌丝量增长最为显著,培养8d,菌丝量分别达到0.800、.73 g/50 mL和0.70g/50 mL;培养过程产孢量处于动态增长趋势,而且不同培养基产孢量大不相同;在察氏和燕麦培养基上产孢量最大,培养8d,产孢量分别达到36.90×10⁶/mL和35.51×10⁶/mL;培养液滤液的毒力随淡紫拟青霉培养时间延长而升高,在察氏培养基培养毒力较高,对茎线虫的最高校正死亡率达到43.44%。     

桃小食心虫病原菌—球孢白僵菌TST05菌株生物学特性研究

[目的]研究从自然染病的桃小食心虫幼虫上分离的球孢白僵菌TST05菌株的生物学特性.[方法]测定不同培养基、外界不同温度和湿度对该菌株菌丝营养生长及孢子萌发的影响.[结果]该菌株在PDA、PPDA、SDAY、SMAY 4种培养基上均生长良好,菌落厚而致密,产孢量均大于3.95×107孢子/mL;菌株适应的温度和湿度范围宽,15～30℃之间,RH 30 ％～100％之间孢子均可萌发、生长和产孢.随着温度接近25℃、湿度增大,孢子的萌发率、菌落的生长速率和产孢量都显著增加.15℃、RH 100％时产孢量为1.32× 107孢子/mL;25℃、RH 30％时,产孢量也能达到1.37×107孢子/mL;25℃、RH 100％时产孢量达到6.19×107孢子/mL.15℃、RH 100％孢子萌发率为52.28％;25℃、RH＞80％时,孢子萌发率都能达到90％以上.[结论]TST05菌株能适应北方干旱低温条件,可开发成为防治桃小食心虫的生物制剂.     

烟草疫霉的产孢和接种方法研究

烟草疫霉是重要的病原真菌,但在人工培养条件下难以培养、产孢以及释放游动孢子.作者对烟草疫霉培养、产孢、接种方法进行了研究.芝麻培养基、黑麦培养基、燕麦培养基可用来培养烟草疫霉,烟草疫霉在三种培养基上平均每天生长量为1.10、0.78、0.86cm;芝麻培养基、黑麦培养基为烟草疫霉产孢子囊较好的培养基,产孢能力强,分别为2.52×104、2.07×104个孢子囊/cm2.而且孢子囊释放率高,分别为43.0%、32.1%.游动孢子囊悬浮液灌根接种和注射接种都能使烟草发病,但不同的接种方法和接种浓度下,病情指数不同.     

云南省马铃薯晚疫病菌交配型及生物学特性研究

 作者对1998~2000年间采自云南省13个县、23个地点的马铃薯晚疫病菌的交配型、菌落形态、燕麦培养基上生长情况、生长速度和产孢量进行了测定。结果显示,采自云南13个县、23个地点的共157个菌株全部为A1交配型,表明云南马铃薯主产区的晚疫病菌以A1交配型为主,同时,被测的代表菌株在生长速度和产孢量上存在显著差异,表明这一地区的晚疫病菌种群内存在丰富的遗传多样性。此外,结果还显示,晚疫病菌菌株在燕麦培养基上的生长情况与其菌落形态和交配型不相关。     

绿僵菌R8-4菌株大量培养固相阶段的条件

研究了昆虫病原真菌绿僵菌R8—4菌株液固两相法培养过程中固相培养阶段的条件，包括培养基载体、接种量、接种后基质含水量、培养过程中的温度、光照、通气量等因素对产孢量的影响。结果表明：蛭石和稻壳均可作为固相培养的优良载体，以蛭石为载体的产孢量稍高于稻壳。玉米粉和麦麸组合是该菌的良好营养源，与不同载体配合均可使产孢量达到20×100孢子／g以上；以小米提供营养的不如麦麸加玉米粉，当小米与载体的质量比大于3：1可获得15×100孢子／g的产孢量。液固接种比以8：10最佳；接种后适宜的基质含水量约为55％，产孢量达28．9×10^8孢子／g；在培养过程中，恒温培养时以25℃为宜；最佳温度调节方式是先在25℃下培养16d后转移到21℃下再培养5d，可获得最高产孢量；光照调节对菌株生长和产孢有重要影响，培养前期在暗环境培养14d，再于光照培养7d的产孢量最高；高通气量利于菌株生长和产孢，应保持容器通气口通畅，培养基厚度以〈4cm为宜。     

梅花炭疽病菌生物学特性研究

梅炭疽病菌（Ｃｏｌｌｅｔｏｔｒｉｃｈｕｍ ｍｕｍｅ）在２０％梅叶汁培养基上菌丝生长最好,而且产孢速度快,其次为ＰＳＡ培养基,病菌分生孢子在５种营养液中均可萌发,以梅叶汁中萌发率最高,葡萄糖液次之,清水对照最差。适合菌丝生长的最适温度为２５℃,适合分生孢子萌发的最适ｐＨ值为５．４,分生孢子在相对湿度８８．５％以上才能萌发,以相对温度１００％中萌发率率最高,在水滴中萌发率较低,持续光照有利于菌丝生长和     

布氏白僵菌MM-1菌株培养条件优化

通过对布氏白僵菌生长和生殖的主要影响因子:培养温度、PPDA培养基中蛋白胨的含量、pH值以及空气相对湿度(RH)进行L9(34)正交试验,以菌落直径日均增长量、开始产孢所需时间、产孢量和孢子萌发率为指标,研究该菌株的最佳组合培养条件,并记录不同处理对菌落的形态、颜色、质地的影响。结果表明:RH=55%时,培养基中蛋白胨8g/L、pH为4,15℃恒温培养,菌株的产孢量最大,产孢最早,菌落生长速度较快,所培养真菌的孢子萌发率较高。不同处理不同培养阶段菌落的培养性状无明显差异。     

楚雄腮扁叶蜂虫生真菌粉红粘帚霉的鉴定及其生物学特性

为明确楚雄腮扁叶蜂Cephalcia chuxiongica病原真菌的种类,以组织分离法对自然罹病死亡的楚雄腮扁叶蜂进行虫生真菌的分离培养,根据形态学特征和rDNA ITS序列分析对所得虫生真菌进行鉴定,并对其中的高毒力菌株进行生物学特性测定。结果表明:共分离得到4属25株菌株,其中以粉红粘帚霉Clonostachys rosea出现频率最高,共分离到15株,均与GenBank中粉红粘帚霉相关菌株亲缘关系最近,ITS序列同源性达100%,属优势种。按照柯赫法则证实4个属的虫生真菌对楚雄腮扁叶蜂均有致病力,其中粉红粘帚霉致病力最强,其高毒力菌株SWFUYHL 02-01对楚雄腮扁叶蜂幼虫致死中时为10 h;蛋白胨马铃薯葡萄糖琼脂培养基最适宜该菌株生长和产孢,其次是马铃薯葡萄糖琼脂培养基;该菌的最适生长温度为25℃,光照对其菌丝生长无显著影响;在以不同种类糖为碳源的培养基上该菌株均能生长,以蔗糖为碳源的培养基上产孢量最高,显著高于以其它糖为碳源时;适宜其生长的氮源是酵母浸出粉,适宜产孢的氮源是硝酸铵和尿素,以硫酸铵和酵母浸出粉为氮源时不产孢;适宜菌丝生长和产孢的无机盐分别是MnSO_4和MgSO_4,添加CaCl_2的培养基上未见产孢;光照对粉红粘帚霉孢子萌发无显著影响。粉红粘帚霉菌株在采样点的出现频率与其生物学特性完全吻合。     

Environmental and Genetic Factors Influencing Self-Fertility in Phytophthora infestans

ABSTRACT Phytophthora infestans is generally regarded as heterothallic-requiring physical proximity of two individuals of different mating type (A1 and A2) for oosporogenesis. Recent reports of limited selfing in young cultures of this oomycete stimulated us to investigate factors contributing to the phenomenon. The ability to produce oospores rapidly (within 2 weeks) in pure, single individual cultures (self-fertility) was tested in 116 individual isolates. The 116 isolates were from geographically diverse locations (16 countries) and were genetically diverse. Mating type and growth medium were the most prominent factors in determining if an isolate would be self-fertile. The majority of A2 isolates (45 of 47 tested) produced oospores when grown on a 50:50 mixture of V8 and rye B medium. In contrast, the majority of A1 isolates (65 of 69 tested) did not produce oospores on this medium. None of the 116 isolates produced oospores when grown on rye B medium (with no V8 juice). Further tests on representative A1 and A2 isolates revealed that oatmeal agar, tomato juice agar, and V8-juice agar all induced the A2 mating type isolate to produce oospores but did not induce the A1 mating type isolate to produce oospores. Calcium carbonate and pH did not alter the self-fertile oospore production in either A1 or A2 mating type isolates. For in vivo tests, the application of fungicide to potato or tomato leaf tissue either before or after inoculation did not stimulate any individual isolate (one A2 and one A1 isolate) to produce oospores in infected tissue. However, in all of the controls for all experiments (in vivo and in vitro), many oospores were produced rapidly if both strains grew in physical proximity.     

Failure to detect highly resistant strains in dicarboximide resistant field populations of Botrytis cinerea1

Field isolates of Botrytis cinerea with moderate levels of resistance to dicarboximide fungicides (ED50 1.0–4.9 μg ml^?1) and to dicloran were obtained from glasshouses where vinclozolin and iprodione failed to control grey mould. From sensitive and moderatcly-resistant cultures, laboratory isolates were selected on dicarboximide-amended medium, which were highly resistant to these fungicides (ED50 125->3000 μg ml^?1). Conidia of all the resistant isolates germinated well on media amended with 100 μg ml^?1 of the dicarboximides vinclozolin, iprodione, procymidone and myclozolin and with 5 μg ml^?1 of metomeclan. However, the spores of the moderately resistant isolates did not germinate on 100 μg ml^?1 metomeclan while the spores of the highly resistant isolates germinated well. Using media with 100 μg ml^?1 of metomeclan to distinguish between the two phenotypes, no highly resistant strain was detected among 312 resistant samples from five cucumber glasshouses with a high frequency of moderately resistant strains. From air-borne inoculum of five glasshouses with 100% resistant populations, 1604 colonies were recovered on vinclozolin-amended (100 μg ml^?1) medium and none on metomeclan-amended (100 μg ml^?1) medium. It is concluded that strains of B. cinerea highly resistant to dicarboximides are absent from field populations.     

Identification of W-type and R-type isolates of Pseudocercosporella herpotrichoides

W-type isolates of Pseudocercosporella herpotrichoides grown on a maize-based agar and exposed to near- ultra-violet radiation at c . 13°C produced a greenish black colour, whilst R-type isolates produced a pink or pale brown colour in the agar medium. More colonies from directly plated lesions or from spore suspensions could be recognized as P. herpotrichoides and could be more easily differentiated as W-type or R-type or as mixtures of both by colour production on maize agar (MA) than by colony morphology on potato dextrose agar (PDA), despite the presence of other fungi. Isolates with intermediate morphology on PDA were positively identified as W-type or R-type on MA; their pathogenicities to wheat and rye seedlings were usually similar to those of W-type or R-type isolates with typical colony morphology, confirming their identification on MA. Drops of mixed suspensions of W-type and R-type spores on PDA formed fast-growing colonies with smooth margins which sometimes had slow-growing sectors with feathery margins. Drops of the same mixtures on MA formed greenish black colonies which sometimes had pink or pale brown sectors. However, when these mixtures were spread onto MA, W-type and R-type colonies could easily be differentiated by colour.     

不同条件下韭菜汁对香蕉枯萎病菌4号小种活性抑制的研究

研究了不同温度、pH值、杀虫剂和杀菌剂的影响下,韭菜汁对香蕉枯萎病菌4号小种的抑制作用,以确定韭菜汁在不同条件影响下对病菌的活力。结果表明,在试验的各温度处理后,55℃以上的温度对韭菜汁的成分有破坏作用,菌落的生长受到显著影响。韭菜根汁对病菌孢子的抑制作用不受pH值的影响。酸性至弱碱性情况下,韭菜茎汁对病菌孢子萌发的抑制率为100%;在强碱性条件下,韭菜茎汁中物质的活性促进了孢子的萌发。供试杀虫剂和杀菌剂对韭菜汁的成分无明显破坏作用。     

适合 Pilidium lythri 菌丝生长和产孢的培养基

由Pilidium lythri引起的草莓褐色叶斑病是在草莓Fragaria×ananassa上发现的一种新病害。病原菌在PDA(马铃薯葡萄糖琼脂)培养基上生长速度慢,产孢量低。为了探讨不同培养基对P.lythri菌丝生长和产孢的影响,筛选适合该病原菌菌丝生长和大量产孢的培养基,本文比较了10种培养基对P.lythri生长和产孢的影响,结果表明,SPDA(添加1.2%草莓果汁的马铃薯葡萄糖琼脂)培养基可以促进P.lythri菌丝生长;CA(胡萝卜琼脂)培养基、V8培养基和TPDA(胰蛋白胨马铃薯葡萄糖琼脂)培养基则可以促进P.lythri大量产生分生孢子。     

Characteristics of Pestalotiopsis Associated with Hardy Ornamental Plants in the UK

Pestalotiopsis isolates obtained from the foliage, stem-base and roots of hardy ornamentals grown on commercial nurseries in the UK were identified and characterised according to pathogenicity and colony morphology. All 18 isolates were identified as Pestalotiopsis sydowiana on the basis of conidia morphology, and confirmation of identification was made by experts at CABI Bioscience. Isolates were pathogenic on the host from which originally isolated. Typical symptoms included foliar browning of foliage and stems, and the presence of black or greenish-black acervuli on diseased tissue. Isolates were not host specific and infected other species of hardy ornamentals. Three colony types on potato dextrose agar were distinguished according to colour and production of acervuli by individual isolates.Three selected isolates of P. sydowiana were characterised by examining the effects of growth media, temperature, pH, and water potential on hyphal extension. Isolates grew well on commonly used growth media, including PDA, Sabouraud dextrose agar (SDA), V8 juice agar (V8), malt extract agar (MEA) and Czapek Dox agar (CDA). The optimum temperature for growth on PDA was in the range 20–25°C, with little or no growth occurring below 5°C or above 30°C. Hyphal extension occurred over a pH range between 2.6–8.6, with optimum values occurring at pH 5.5. In general, decreases in osmotic and matric potential caused a reduction in growth. Hyphal extension on media adjusted osmotically as NaCl ceased between –9.9 and –10.5MPa. Isolates were more tolerant of osmotic than matric potential, with no growth occurring at –6.5MPa on media adjusted with polyethylene glycol.     

百合疫病病原菌的鉴定及培养基的筛选

从具典型症状的新鲜百合疫病植株茎基部病组织中分离到百合疫霉菌,根据其病原菌菌丝的形态、菌落特征,厚垣孢子、游动孢子囊和卵孢子的形态和大小,以及病原菌致病性测定,该病原菌鉴定为烟草疫霉Phytophthora nicotianae van Brede de Haan.供试的16种培养基中,病原菌在胡萝卜琼脂培养基(CaA)和辣椒琼脂培养基(PeA)上生长最好,生长速率分别为1.771和1.770mm/h.在常规培养条件下,病原菌不易产生厚垣孢子、游动孢子囊和卵孢子,在低温、皮氏溶液和土壤浸出液中分别诱导产生出大量厚垣孢子、游动孢子囊和卵孢子.     

Characterization of fenarimol-resistant mutants of Aspergillus nidulans

The fitness of twelve fenarimol-resistant mutants of Aspergillus nidulans was tested with respect to spore germination, germ tube elongation, hyphal growth and sporulation. Half of the strains tested were isolated on triarimolcontaining media. The other strains were selected on imazalil-or cycloheximide-containing media (Van Tuyl, 1977).A number of mutant strains produced spores with unimpaired viability on synthetic medium. In other strains a reduction in spore viability was noticed. The rate of germ tube elongation of all resistant mutants was significantly lower than that of the wild-type strain. Mutant strains with a low degree of resistance always had an almost normal mycelial growth rate, whereas growth of some of the strains with a relatively high degree of resistance was significantly slower. Spore production on malt agar was highest in the wild-type strain and was found to be lower in fenarimol-resistant mutants. In most of the mutant strains tested a high degree of cross-resistance between fenarimol, imazalil and triadimefon was established; in some of them cross-resistance to these chemicals was low or even absent.Possible implications of the results described for the chance of development of resistance in phytopathogenic fungi to sterol biosynthesis-inhibiting fungicides are discussed.     

A new medium for the detection of fluorescent pigment production by pseudomonads

Two media (King’s B [KB] and CSGA) commonly used for the detection of fluorescent pigment by Pseudomonas spp. were compared to a new medium proposed in this study, PGS agar. Thirty‐nine strains of 10 different species of Pseudomonas from several geographic regions were screened. The efficacies of these media were examined under several conditions, including the addition of iron‐binding substances or supplementation with extra iron. The medium developed, which included an iron‐binding agent, was the most permissive for production of fluorescent pigments when compared to KB and CSGA. Thirty‐seven of the 39 pseudomonad strains screened were highly fluorescent on this new medium compared to 15 and 16 strains, respectively, on KB or CSGA. The optimal composition of the medium per litre was Bacto peptone 10 g, gelatin 20 g, sucrose 20 g, agar 15 g, dipotassium hydrogen phosphate 1 g, magnesium sulphate heptahydrate 1 g and conalbumin 2 g. Protocol validation tests performed through an intra‐laboratory study in comparison to KB demonstrated the effectiveness of the new PGS medium.     

Diversity of Virulence in Phytophthora parasitica on Tobacco, as Reflected by Nuclear RFLPs

ABSTRACT A worldwide collection of P. parasitica isolates was investigated for the ability to infect tobacco and tomato, as related to elicitin production. Elicitin was produced by all nontobacco isolates, and nonproducing strains all were isolated from tobacco. In addition, producing strains were isolated from tobacco and coexisted with nonproducing (TE ) strains. Elicitin production generally was associated with low virulence on tobacco and frequent pathogenicity on tomato, whereas TE isolates generally were highly virulent and specialized to tobacco. Analysis of both mitochondrial and nuclear DNA restriction fragment length polymorphisms indicated, for the first time, that black shank isolates can be distinguished from other P. parasitica isolates on the basis of genetic criteria. Our results suggest that severe black shank is caused by a limited number of TE strains that have been disseminated by clonal evolution. Mutations in the TE phenotype seem to have arisen independently in several genetic backgrounds and distinct geographic areas. The fortuitous absence of elicitin production has precluded population replacements in areas of intensive tobacco cultivation. Thus, monitoring the loss of elicitin production in developing tobacco areas should be considered in disease management.