温度对贵州不同种植区域白术白绢病菌的影响

对贵州不同种植区域的白术白绢病菌(Sclerotium rolfsii Sacc.)菌株进行不同温度培养,比较菌丝生长、产核量、菌核萌发情况.结果表明,来源于不同种植区域的白术白绢病菌菌株在相同培养温度条件下菌丝生长速率、产核量、菌核萌发率存在较大差异;在适宜温度范围内,菌丝生长速率、产核量、菌核萌发率与培养温度相关;菌丝生长速率、产核产量和菌核萌发率相关关系不明显.     

6种培养基对不同来源白术白绢病菌培养的影响

6种培养基对不同来源白术白绢病菌培养的影响研究结果表明,6种培养基上,4个不同来源地菌株菌丝生长和菌核产量存在一定的差异,尤其是菌株LA20,在几种供试培养基上长势均较其他3个菌株差,产核量也最少。比较几种培养基上供试菌株生长状况和产核量的关系发现,供试4个菌株产菌核量与菌丝的生长状况呈一定的正相关关系,即在同一个培养基上菌株菌丝生长越好,产核量也越多。     

The use of Solacol® (validamycin) as a growth retardant in the isolation of soil fungi

Solacol^®, a formulation of the antibiotic validamycin, at 0.33% in 2% malt extract agar, reduced the spread of fungi on dilution plates drastically and allowed twice as much incubation time before subculturing; this resulted in an elevated number of species isolated. Using pure cultures of 62 common soil fungi, it was shown that all fast-growing species (exceptPythium ultimum) were efficiently inhibited but not completely suppressed. Inhibition was comparable to that by 0.5% oxgall, though, while this substance completely suppressed several species, Solacol very strongly inhibited onlyGaeumannomyces graminis, Gerlachia nivalis, Harzia acremonioides, Verticillium biguttatum andRhizoctonia solani. In a further experiment each separate constituent of Solacol was tested against 22 fungi at equivalent concentrations. Validamycin strongly inhibitedChaetomium globosum and two Basidiomycetes, though hardly more than the non-ionic detergent which mainly inhibited the other fungi. A few species were, however, more inhibited by Solacol than by the detergent alone. Solacol at 0.33% is a suitable aid in dilution plating of soil fungi, by increasing the number of colonies and species observed.Samenvatting Solacol^®, een formulering van het antibioticum validamycine, remde de groei van schimmels in verdunningsplaten met een concentratie van 0.33% in 2% moutagar en maakte het mogelijk de periode tot afenten met een factor 2 te verlengen; daardoor was het aantal geïsoleerde soorten duidelijk toegenomen. Met reincultures van 62 algemene grondschimmelsoorten werd aangetoond, dat alle snelgroeiende soorten (met uitzondering vanPythium ultimum) voldoende geremd, maar niet volkomen onderdrukt werden. Het remmingspercentage was vergelijkbaar met dat van 0.5% ossegal, hoewel dit laatste sommige soorten volkomen onderdrukte; Solacol remde alleenGaeumannomyces graminis, Gerlachia nivalis, Harzia acremonioides, Verticillium biguttatum enRhizoctonia solani zeer sterk. In een volgend experiment werden de componenten van Solacol t.o.v. 22 fungi apart getoetst in concentraties equivalent aan 0.33% Solacol. Validamycine remde alleenChaetomium globosum en twee basidiomyceten behoorlijk, maar nauwelijks meer dan de niet-ionische uitvloeier, die in hoofdzaak de overige remeffecten veroorzaakte. Enkele soorten werden echter door het complete Solacol veel sterker geremd dan door de uitvloeier alleen. Solacol in een verdunning van 0,33% wordt aanbevolen bij verdunningsplaten voor het isoleren van grondschimmels ten einde het aantal kolonies en soorten te verhogen.     

Effect of seed treatment of<Emphasis Type="Italic">Arachis hypogaea</Emphasis> with<Emphasis Type="Italic">Bacillus subtilis</Emphasis> on nodulation in biocontrol of southern blight (<Emphasis Type="Italic">Sclerotium rolfsii</Emphasis>) disease

The employment of formulatedBacillus subtilis for peanut seeds (Arachis hypogaea cv. ‘Shulamit’) counteracted the destructive effects of the seedborne pathogenSclerotium (Athelia)rolfsii on the nodulation, leghemoglobin and nitrogenase activity of peanuts. Moreover, the changes in crop vigor index, total nitrogen content and survivability of bothRhizobium spp. andB. subtilis have been related to compatibility and even an occasional synergism between them. http://www.phytoparasitica.org posting Nov. 12, 2006.     

不同钾肥对虎奶菇菌核产量与氨基酸含量的影响

运用灰色系统理论,探讨了不同K肥相同含K量添加培养料栽培虎奶菇菌对产量与不同种类氨基酸总量的影响。结果表明,以硝酸钾为K肥对虎奶菇菌核产量与氨基酸含量影响的关联度最大,其次为氯化钾处理,硫酸钾处理关联度最小,这与栽培试验结果相一致。     

蝴蝶兰白绢病防治药剂筛选及防治适期研究

采用灌根和叶片喷雾的处理方法,对蝴蝶兰白绢病灌根和叶面喷施防治药剂进行了筛选,并对防治适期进行了研究。结果表明：在灌根防治中以“根好”1000倍液效果最好,其平均发病率为2．8％,防治效果为89．8％;效果最佳的叶面喷施防治药剂为“恶霉灵”1500倍液,其平均发病率为5．6％,防治效果为80．1％;最佳防治时期为2．5寸杯苗换杯前5d。     

防治茉莉白绢病的药剂筛选研究

[目的]筛选防治茉莉白绢病菌的化学药剂和生防菌。[方法]采用生长速率法和抑菌圈法测定化学药剂和生防菌对茉莉白绢病菌的抑制作用,采用盆栽试验测试化学药剂和生防菌以及化学药剂和生防菌复配对茉莉白绢病的防治作用。[结果]测试的9种化学农药和6种生防菌中,25%戊唑醇可湿性粉剂和芽孢杆菌Bv22菌株对茉莉白绢病菌生长的抑制作用最强,其LC50分别为2690.96cfu/ml和200.05μg/L,且25%戊唑醇可湿性粉剂对芽孢杆菌Bv22菌株的生长无抑制作用。室内防治试验结果表明,25%戊唑醇可湿性粉剂100mg/L和芽孢杆菌Bv22菌株108cfu/ml以及25%戊唑醇可湿性粉剂200mg/L＋芽孢杆菌Bv22菌株107cfu/ml和25%戊唑醇可湿性粉剂400mg/L＋芽孢杆菌Bv22菌株106cfu/ml对茉莉白绢病的防治效果分别为84.44%、60.00%、96.67%和96.67%。[结论]化学药剂和生防菌复配对茉莉白绢病的有较好的防治作用。     

椒草白绢病菌生物学特性及其防治药剂的初步研究

[目的]了解椒草白绢病菌的生物学特性和筛选有效的杀菌剂。[方法]采集具有典型症状的病害标本,根据柯赫氏法则分离病原物,并分别测定不同的温度、湿度、pH值以及碳氮源和光照对该病菌菌丝生长和菌核萌发的影响,同时,测试5种杀菌剂在3种不同浓度下对病原菌的抑菌作用。[结果]结果表明,白绢病菌菌丝生长最适温度为30℃,最适pH值为6,最适合的碳源、氮源为蔗糖和硝酸钾;黑暗条件有利于菌丝的生长,而光照条件有利于菌核的产生。当pH值为4～6时,培养2 d后菌核的萌发率达100%;菌核的萌发需要足够的水分。供试药剂中以3%水剂井冈霉素和50%使百功防效最为明显,分别在400和200μg/m l时的防效高达98%以上。[结论]温暖潮湿、偏酸性的环境适合白绢病菌的生长和繁殖,井冈霉素可作为防治白绢病的有效药剂用于田间该病害的控制。     

Comparison of Physical, Chemical and Biological Methods of Controlling Garlic White Rot

Treatment of garlic cloves with tebuconazole (at 1ml of Folicur 25% l^–1) achieved a significant reduction in the rate of disease progress and the final incidence of plant death by Sclerotium cepivorum: garlic yields were improved. Although soil solarization provided the best control of garlic white rot, bringing soil populations of S. cepivorum to negligible levels, similar levels of disease control and garlic yields were achieved when tebuconazole was sprayed to stem bases of plants grown from cloves also treated with tebuconazole. This double treatment almost doubled the yield compared with untreated plants and significantly increased bulb quality under high disease pressure conditions. Soil solarization was also highly effective in a second consecutive crop of garlic, with significant improvements in yield and garlic quality. In contrast, lower levels of disease control were obtained when selected isolates of Trichoderma harzianum and Bacillus subtilis were applied to the soil and cloves respectively.     

Effect of formulation on the rhizosphere competence and biocontrol ability of Trichoderma atroviride C52

The rhizosphere competence of the biological control agent Trichoderma atroviride isolate C52 was studied on onion roots both in the glasshouse and in the field when introduced into soil in a range of formulations. Proliferation of T. atroviride in the rhizosphere was formulation-dependent. A pellet formulation maintained the fungal concentration at 10⁵ cfu per g soil, whereas solid-substrate and seed-coating formulations gave concentrations of 10⁴ and 10¹ cfu per g soil, respectively. To facilitate rhizosphere-competence studies, a UP-PCR band profile generated with primer L45 for isolate C52 was used to enable conclusive identification of T. atroviride C52 when recovered from soil. When isolate C52 was introduced into Sclerotium cepivorum -infested soil as both pellet and solid-substrate formulations, there was no statistically significant difference in the disease control between these treatments, but the pellet treatment doubled the percentage of healthy plants compared with the control treatment.