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1.
Formulation matrices can play an important role in improving the storage survival and biocontrol efficacy of microorganisms used for the control of pest insects. In this study, liquid culture-produced blastospores of the entomopathogenic fungus Paecilomyces fumosoroseus were formulated with different inert and organic materials prior to air-drying. Paecilomyces fumosoroseus blastospores were produced in two different liquid media, a basal salts medium supplemented with Casamino acids and glucose (LM1) and a medium containing peptone of collagen and glucose (LM2). Blastospores produced in the two test media were formulated with various supports. The formulation supports were cornstarch, rice flour, talc powders, Mexican lime, calcined kaolin clay, and diatomaceous earth. Several of the supports were tested at different concentrations. The initial and long-term (after storage at 4 and 28 °C) survival of the formulated, air-dried blastospores were evaluated. Initial blastospore viabilities were affected by the formulation material and by the blastospore production medium. Medium composition, drying support and storage temperature had an impact on the long-term survival of the blastospores. Under the conditions of the study, LM1 produced higher concentrations of blastospores that not only survived drying better than blastospores produced in LM2 but also maintained viability longer during storage in the formulation supports tested. The nature of the drying supports was shown to have a significant impact on the storage stability of all blastospores, particularly those produced in LM1. Under the production, drying and storage conditions used in the study, calcined kaolin clay formulations stored at 4 °C had the best storage stability. In all formulations tested, spore survival over time was reduced for blastospore formulations stored at 28 °C rather than 4 °C.  相似文献   

2.
Gary J. Puterka 《BioControl》1999,44(2):183-209
This paper reviews the research on entomopathogenic fungi in orchard systems and presents research on a mycoinsecticidal approach to an important pest of pear, the pear psylla. The review identifies the host-pathogen relationships that have been examined to date, the microbial formulation and application strategies that have been used, and the results that were obtained. The mycoinsecticides used in the pear psylla research were based on conidia of Beauveria bassiana (ARSEF #2860) and Paecilomyces fumosoroseus (ARSEF #2658). These were formulated into sprayable solutions containing water, 0.1% or 0.5% Ultrafine Sunspray oil (paraffinic oil) in water, or 0.1% acrylic polymer (StressguardTM) in water. Final spray solutions that contained 6 × 106 conidiospores/ml were applied to psylla nymph infested trees at a rate of 5.39 × 1013 conidiospores/ha during the 1993--1995 seasons. In addition, two commercial formulations of B. bassiana, GHA from Mycotech and Naturalis L from Fermone Corp., were mixed in water at the same conidiospore application rates as the other fungal isolates. Single applications of the ARSEF fungal strain/formulation combinations produced psylla nymphal mortalities that ranged from 18.2--37.1%, but the results varied with formulation. Conidia formulated with acrylic polymers in water caused significantly higher mortalities several days earlier than either the water or water and oil combination in 1993. However, no significant differences among pathogen/formulation combinations occurred in 1994 or 1995. The performance of Naturalis L was comparable to the ARSEF fungal strain/formulation combinations with peak nymphal mortalities of 34.1%, while GHA produced a significantly lower peak mortality of only 10.8%. However, because of the low conidiospore concentrations in the Naturalis L formulation, final spray solutions contained nearly 25% of the oil-like carrier. Thus, psylla mortalities may not have been entirely attributed to mycosis. Based on the results from the ARSEF fungal formulations, a mycoinsecticidal approach to pear psylla management could be a useful component in an integrated pest management program for pear.  相似文献   

3.
The Organic Materials Review Institute (OMRI) is a non-profit organisation providing an independent review of products intended for use in organic production systems to certify compliance with US national organic standards. Since all adjuvants to be used in organic agriculture production are required to meet these standards, OMRI's certified list of products is a convenient starting point when developing organic pest control formulations. In the current study, six OMRI-certified surfactants are tested for their compatibility with three common entomopathogens: Beauveria bassiana, Metarhizium brunneum and Isaria fumosorosea. The fungi were evaluated in two common propagule forms, solid-state produced conidia and liquid-media produced blastospores. The results show that most of the surfactants are compatible with the fungi at a high surfactant concentration (2% w/v). In general, the conidia showed a higher susceptibility (greater reduction in spore germination) to the surfactants than the blastospores under these conditions. In addition, the surface tension and foaming properties of the surfactants were determined.  相似文献   

4.
Several classes of surfactants/foaming agents were screened for compatibility with blastospores of Paecilomyces fumosoroseus. The surfactants were assayed to determine their influence on the rate of germination, viability and conidia production by the blastospores. Surfactants compatible with blastospores were then assayed for their foam forming properties using a commercially available foam generator. These tests identified keratin hydrolysate as the only suitable surfactant in terms of biocompatibility and foam forming properties. Laboratory bioassays were conducted to determine the effect of keratin hydrolysate on the efficacy of blastospores against Formosan subterranean termites. The results showed keratin hydrolysate increased the efficacy of P. fumosoroseus and suggest that this foam formulation of P. fumosoroseus may be useful in controlling Formosan subterranean termites.  相似文献   

5.
防治西花蓟马的病原真菌-白僵菌微菌核的液体培养   总被引:1,自引:0,他引:1  
微菌核是许多植物病原真菌产生的越冬结构,目前还没有关于白僵菌微菌核的报道。用含不同氮源的介质培养出了2株白僵菌菌株,RSB和SZ21的微菌核。在液体培养条件下,2株菌株不仅能产生典型的芽孢和菌丝,还能产生微菌核。在以玉米粉(RSB和SZ21菌株分别为6.5×102和6.3×102mL-1)为氮源的介质中产生的微菌核浓度高于以大豆粉(RSB和SZ21菌株分别为2.5×102和2.2×102mL-1)为氮源的介质。菌株SZ21产生的芽孢浓度(在以大豆粉和玉米粉为氮源的介质中,分别为17.9×105和7.4×105L-1)高于RSB菌株的芽孢浓度(在以大豆粉和玉米粉为氮源的介质中,分别为14.8×105和6.2×105L-1)。含有硅藻土的微菌核制剂能在真空干燥(<5%湿度)后存活下来,并且对于活力没有显著影响。干燥后的微菌核颗粒在水洋菜培养基上复水和培养后,能够萌发菌丝和产生高浓度的分生孢子。将微菌核颗粒预混到土壤中能引起西花蓟马Frankliniella occidentalis(Pergande)土栖阶段的高死亡率。这是首次报道白僵菌的微菌核的培养,并为用虫生真菌防治土栖昆虫提供了一个新的方法。  相似文献   

6.
Blastospores of three strains of Metarhizium anisopliae were stored in 18 liquids at 4°C, 20°C and 35°C for 18 weeks, 12 weeks or 9 days respectively. Viability was quantified by determination of their germination. In bioassays the virulence of stored blastospores was studied using adults and third instars of Locusta migratoria migratorioides (R. & F.) and compared to those of freshly produced blastospores and conidia. Generally, there was great variability in the viability of blastospores, depending on the fungal strain and the liquids used. Blastospores survived best at 4°C in 10% hydroxyethyl starch; for example, germination of M. anisopliae strain 97 still amounted to more than 80% after storage for 18 weeks. Other suitable liquids were deionized water, 25% Ringer's solution and 1% sodium alginate. The viability of blastospores stored at 20°C was considerably shorter than at 4°C. During storage for 12 weeks at 20°C the best protective liquids for M. anisopliae strain 97 were 25% Ringer's solution (43% germination), deionized water (23%) and 10% hydroxyethyl starch (23%). At 35°C, 45% of M. anisopliae strain 97 blastospores still germinated after storage for 7 days in 25% glycerol. The bioassays revealed that the virulence of blastospores after storage was comparable to that of fresh ones and even better than that of fresh conidia. In general, the LT50 was about 4–6 days at an alternating day/night temperature of 28/20°C.  相似文献   

7.
Two exotic fungal isolates, one of Beauveria bassiana (268–86) and another of Metarhizium anisopliae (100–82), three local isolates of B. bassiana (isolates I, II, III) and one of the entomogenous bacteria Serratia marcescens, were tested for pathogenicity against the banana weevil Cosmopolites sordidus. All four isolates of B. bassiana and the one of M. anisopliae were found to be pathogenic to third—instar larvae of C. sordidus, causing mortalities of 98–100% by 9 days post—exposure to dry fungal spores. M. anisopliae was the least pathogenic to larvae with LT50 of 4.2 days, compared to 3.5, 3.3, 3.6 and 4.0 respectively for isolates I, II, III and 268–86. B. bassiana was also pathogenic to adult C. sordidus, causing mortalities varying from 63–97% by 35 days post—exposure depending on isolate. As for larvae M. anisopliae exhibited low pathogenicity for the adult C. sordidus. In general, all the fungi tested were less pathogenic to adult weevils (LT50 = 17.5; 12.5; 8.0 and 22.0 days) for isolates I, II, III and 268–86 respectively, while isolate 100–82 failed to kill 50% of adults even by 35 days post—exposure. Incubation of dead weevils in a moist environment led to development of surface mycelia starting from intersegmental junctions. Histopathology revealed extensive destruction of internal organs by hyphae which invaded most of the organs. The LT50 for S. marcescens against C. sordidus larvae was 2.8 days. However, the bacterium did not kill adult C. sordidus even at 10 times the concentration applied on larvae.  相似文献   

8.
One of the major constraints for banana production in Uganda is the banana weevil, Cosmopolites sordidus (Germar), (Coleoptera: Curculionidae). Investigations were carried out to evaluate the efficacy of maize, soil-based and oil formulations of an indigenous isolate of Beauveria bassiana for the control of the banana weevil. Weekly trapping of weevils over a 9-month monitoring period showed significant reduction in unmarked and marked weevil population in B. bassiana treated plots. Application of maize formulation at 2 ×10 15 conidia ha -1 proved most effective, reducing the weevil populations by 63-72% within 8 weeks after a single application. The soil based formulation at 2 ×10 14 conidia ha -1 was intermediate while the oil formulation at 6 ×10 15 conidial ha -1 was least effective. Trapping efficiency declined in B. bassiana treated and untreated banana plots but was greatest in the latter.  相似文献   

9.
A conidial suspension of the entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin, was injected into corn plants at anthesis to suppress populations of the European corn borer Ostrinia nubilalis (Hübner) (Lepidoptera: Pyralidae). The fungus colonized the plants and moved, primarily upward, within the pith, possibly along with plant photosyn‐thates. Beauveria bassiana injected into the corn plants significantly reduced the amount of European corn borer tunneling. Colonization of corn plants by B. bassiana was independent of European corn borer infestation. The impact of environmental conditions on the movement and colonization of the plants by B. bassiana is discussed.  相似文献   

10.
Zusammenfassung Für Infektionsversuche und biologische Bek?mpfung k?nnen Massenkulturen vonBeauveria bassiana entweder Konidien oder Blastosporen liefern. Die qualitative Bewertung solcher Sporen und Sporenpr?parate und ebenso deren Standardisierung setzen voraus, dass auch das Keimverhalten der Sporen bekannt ist. Deshalb wurden die zeitabh?ngigen Keimungsprozente und Keimungskurven der Blastosporen und Konidien eines Stammes vonB. bassiana auf Malzextrakt-Pepton-Agar bei 24 und 18°C ermittelt und damit auch die Unterschiede, die durch Temperatur und Sporenart bedingt sind. Für die Bewertung und Standardisierung von Sporen und Sporenpr?paraten k?nnen die Keimprozente nach 24 und 36 Stunden oder die Zeit für 50% Keimung Kriterien sein und mit den hier wiedergegebenen Standardwerten verglichen werden.
Summary Mass cultures ofBeauveria bassiana provide either conidia or blastospores for laboratory experiments and biological control measures. For qualitative evaluation of spores and spore preparations it is of primary importance to know the germination behaviour of spores. Therefore, the percentage germination of blastospores and conidia in relation to time (0–36 hours) and temperature (24 and 18°C) have been determined on malt-extract peptone agar (Table 1) and demonstrated by graphs (Fig. 1). The periods of time necessary for 50% germination of blastospores and conidia show differences depending on temperature and type of spore (Table 2). Pronounced differences of percentage germination as caused by the two temperatures become obvious with blastospores after 6–10, with conidia after 15–20 hours; after 24 hours, such differences are relatively low (Table 3). For evaluation and standardization of spores and spore preparations ofB. bassiana the percentage germination at 24°C as obtained after 24 and 36 hours or the period of time for 50% germination can be used as criteria and compared with the corresponding standard values presented.
  相似文献   

11.
The production of fungal spores using on-site, non-sterile, portable fermentation equipment is technically constrained. Very little information is available on the production requirements, such as medium concentration, inoculum stabilization, required fermentation times, and maintenance of axenic growth. In this study, we developed a two-part, liquid concentrate of the production medium that remains stable and soluble at room temperature. We also examined inoculum stability and showed that freeze- or air-dried blastospore preparations were stable for 7 days after rehydration when stored at 4 °C. The use of a low-pH (pH 4), relatively rich complex medium provided a growth environment deleterious to bacterial growth yet conducive to rapid sporulation by Paecilomyces fumosoroseus. High concentrations of blastospores (7.9×108/ml) of P. fumosoroseus were produced in a 40-h fermentation with very low levels of bacterial contamination when the fermentor was charged with a blastospore production medium with a starting pH of 4 and inoculated with blastospore concentrations greater than 1×106 spores/ml. These studies demonstrate that the use of disinfected, portable fermentation equipment has potential for on-site production of high concentrations of blastospores of the bioinsecticidal fungus P. fumosoroseus.  相似文献   

12.
The present work aims at tracing the essential‐oil diversity of wild growing Origanum majorana plants in Cyprus. The study of six populations scattered over the western part of the island has shown that the essential oils were rich either in trans‐sabinene hydrate/terpinen‐4‐ol or in α‐terpineol/trans‐sabinene hydrate. The former oil type is more common and responsible for the typical marjoram odor of the plants. The comparison of our results with published data concerning wild and cultivated O. majorana showed that the oil composition of the Cypriot populations had not been reported from wild plants from other parts of the Mediterranean region, while it is very common among the cultivated plants. Thus, it seems probable that the nowadays cultivated marjoram may originate from Cypriot wild populations.  相似文献   

13.
The entomopathogenic fungus Beauveria bassiana produces at least three distinct single-cell propagules, aerial conidia, vegetative cells termed blastospores, and submerged conidia, which can be isolated from agar plates, from rich broth liquid cultures, and under nutrient limitation conditions in submerged cultures, respectively. Fluorescently labeled fungal cells were used to quantify the kinetics of adhesion of these cell types to surfaces having various hydrophobic or hydrophilic properties. Aerial conidia adhered poorly to weakly polar surfaces and rapidly to both hydrophobic and hydrophilic surfaces but could be readily washed off the latter surfaces. In contrast, blastospores bound poorly to hydrophobic surfaces, forming small aggregates, bound rapidly to hydrophilic surfaces, and required a longer incubation time to bind to weakly polar surfaces than to hydrophilic surfaces. Submerged conidia displayed the broadest binding specificity, adhering to hydrophobic, weakly polar, and hydrophilic surfaces. The adhesion of the B. bassiana cell types also differed in sensitivity to glycosidase and protease treatments, pH, and addition of various carbohydrate competitors and detergents. The outer cell wall layer of aerial conidia contained sodium dodecyl sulfate-insoluble, trifluoroacetic acid-soluble proteins (presumably hydrophobins) that were not present on either blastospores or submerged conidia. The variations in the cell surface properties leading to the different adhesion qualities of B. bassiana aerial conidia, blastospores, and submerged conidia could lead to rational design decisions for improving the efficacy and possibly the specificity of entomopathogenic fungi for host targets.  相似文献   

14.
Abstract The eucalypt plantation industry in Western Australia provides a unique opportunity to study the movement of pathogens between closely related host taxa. Eucalyptus globulus, a native to Tasmania and south‐eastern Australia, is the predominant species in Western Australian plantations, often being planted adjacent to native forest containing Eucalyptus marginata and Eucalyptus diversicolor. Since the commencement of the plantation industry 20 years ago, several fungal species, previously known only to eastern Australia or overseas, have been reported on E. globulus in Western Australia. Botryosphaeria australis is a newly described species, recently found causing cankers on Acacia spp. in eastern Australia. However, during a routine survey, B. australis was found to be the predominant species associated with E. globulus plantations and native Eucalyptus spp. in Western Australia. In this study, six short simple repeat markers were used to evaluate genetic diversity and gene flow between collections of B. australis from native eucalypt forest and E. globulus plantations at two locations in south‐western Australia. In both cases, there was no restriction to gene flow between the plantations and the adjacent native forest. Botryosphaeria australis has now been isolated from a wide range of hosts across south‐western Australia and was not isolated from E. globulus in Tasmania or South Australia. This extensive distribution and host range suggests B. australis is native to Western Australia. This study demonstrates the ability of a pathogen to move between plantation and forests.  相似文献   

15.
The antimicrobial activity of five samples of Taxandria fragrans essential oil was evaluated against a range of Gram‐positive (n= 26) and Gram‐negative bacteria (n= 39) and yeasts (n= 10). The majority of organisms were inhibited and/or killed at concentrations ranging from 0.06–4.0% v/v. Geometric means of MIC were lowest for oil Z (0.77% v/v), followed by oils X (0.86%), C (1.12%), A (1.23%) and B (1.24%). Despite differences in susceptibility data between oils, oils A and X did not differ when tested at 2% v/v in a time kill assay against Staphylococcus aureus. Cytotoxicity assays using peripheral blood mononuclear cells demonstrated that T. fragrans oil was cytotoxic at 0.004% v/v but not at 0.002%. Exposure to one or more of the oils at concentrations of ≤0.002% v/v resulted in a dose responsive reduction in the production of proinflammatory cytokines IL‐6 and TNF‐α, regulatory cytokine IL‐10, Th1 cytokine IFN‐γ and Th2 cytokines IL‐5 and IL‐13 by PHA stimulated mononuclear cells. Oil B inhibited the production of all cytokines except IL‐10, oil X inhibited TNF‐α, IL‐6 and IL‐10, oil A inhibited TNF‐α and IL‐6, oil C inhibited IL‐5 and IL‐6 and oil Z inhibited IL‐13 only. IL‐6 production was significantly inhibited by the most oils (A, B, C and X), followed by TNF‐α (oils A, B and X). In conclusion, T. fragrans oil showed both antimicrobial and anti‐inflammatory activity in vitro, however, the clinical relevance of this remains to be determined.  相似文献   

16.
Beauveria bassiana is an important entomopathogenic fungus widely commercialized in the world. Recent progress and achievements on conidia production have focused on a yield goal of 109 to 1010 conidia per gram of dry substrate. Due to cost-competitive perspectives, these yields should be associated with better production rates or productivities. This study presents a review of relevant studies of B. bassiana conidia production on solid-state cultures and the parameters that should be taken into account to maintain constant quality in the product to be commercialized. Conditions for maximizing production and infectivity of B. bassiana conidia are also analysed.  相似文献   

17.
Aims: Strains of Trichoderma spp. produce numerous bioactive secondary metabolites. The in vitro production and antibiotic activities of the major compounds synthesized by Trichoderma harzianum strains T22 and T39 against Leptosphaeria maculans, Phytophthora cinnamomi and Botrytis cinerea were evaluated. Moreover, the eliciting effect of viable or nonviable biomasses of Rhizoctonia solani, Pythium ultimum or B. cinerea on the in vitro production of these metabolites was also investigated. Methods and Results: T22azaphilone, 1‐hydroxy‐3‐methyl‐anthraquinone, 1,8‐dihydroxy‐3‐methyl‐anthraquinone, T39butenolide, harzianolide, harzianopyridone were purified, characterized and used as standards. In antifungal assays, T22azaphilone and harzianopyridone inhibited the growth of the pathogens tested even at low doses (1–10 μg per plug), while high concentrations of T39butenolide and harzianolide were needed (>100 μg per plug) for inhibition. The in vitro accumulation of these metabolites was quantified by LC/MS. T22azaphilone production was not enhanced by the presence of the tested pathogens, despite its antibiotic activity. On the other hand, the anthraquinones, which showed no pathogen inhibition, were stimulated by the presence of P. ultimum. The production of T39butenolide was significantly enhanced by co‐cultivation with R. solani or B. cinerea. Similarly, viable and nonviable biomasses of R. solani or B. cinerea increased the accumulation of harzianopyridone. Finally, harzianolide was not detected in any of the interactions examined. Conclusions: The secondary metabolites analysed in this study showed different levels of antibiotic activity. Their production in vitro varied in relation to: (i) the specific compound; (ii) the phytopathogen used for the elicitation; (iii) the viability of the elicitor; and (iv) the balance between elicited biosynthesis and biotransformation rates. Significance and Impact of the Study: The use of cultures of phytopathogens to enhance yields of Trichoderma metabolites could improve the production and application of novel biopesticides and biofertilizers based on the active compounds instead of the living microbe. This could have a significant beneficial impact on the management of diseases in crop plants.  相似文献   

18.
Developing a dual agent biopesticide formulation made with blastospores of Beauveria bassiana (Balsamo) Vuillemin strain GHA (Bb) at the ratio of 1:1 mixed with traditional fermentation production of Bacillus thuringiensis kurstaki (Btk) spores and crystals were studied. Twelve potential formulation ingredients were screened for their impact on insecticidal activity, microbe viability, UV protection and product suspensibility of a spray dried Bt/Bb (1:1) mixture applications to cabbage plants against cabbage looper, Trichoplusia ni. Based on the results, Spray-dried mixtures of Bt/Bb made with biochar, chitosan and skim milk powder formulations gave the greatest efficacy and higher solar stability when exposed to simulated sunlight. They therefore can be used as a formulation that combines Bt with Bb in one product. However, the formulation made with aitkin component had significantly more colony forming units (CFUs) of Bt, whereas, formulations made with albumin, sodium carbonate and pharmamedia had more Bb CFUs than other formulations. Albumin, pharmamedia, skim milk powder and biochar had significantly better suspension in water (less settling) than others. These results support the concept of formulating the two biocontrol agents, B. thuringiensis and B. bassiana blastospores for greater efficacy, more viability and longer field persistence as an environmentally friendly sustainable pest control tool.

LSID:urn:lsid:zoobank.org:pub:568D6FE6-E876-417B-BE39-C51F7CBAD6AB  相似文献   


19.
The present study aimed to evaluate the in vitro pathogenicity of the Metarhizium anisopliae s.l. CG 112, CG 347, CG 32, CG 148 and CG 629 isolates formulated in vegetable or mineral oil against Rhipicephalus microplus. The bioassays were performed with R. microplus engorged females. The ticks were immersed for three minutes in oil-based formulations containing 10% oil (mineral or vegetable). The effects of the different fungal isolates were evaluated analyzing the females’ reproductive parameters (the total weight of the egg mass, hatching percentage, egg production index and nutritional index). The present study showed that all of the tested isolates and both oil formulations (vegetable or mineral oil) changed the biological parameters of the R. microplus females. However, the mineral oil formulation was more effective than the vegetable oil formulation, as the former showed a higher tick control percentage. It was concluded that there was variation in the virulence among the different M. anisopliae s.l. isolates and between the different types of oil. Moreover, that either of the isolates GC 148 and GC 629 formulated in oil confers the good potential for controlling R. microplus engorged females.  相似文献   

20.
The oil rose, Rosa damascena Mill. (Rosaceae) is an agricultural crop cultivated in various countries of the northern hemisphere, such as Turkey, Bulgaria, Morocco, Iran, Egypt, France, China and India. Iran, presently, is the largest producer of rose water in world. The major production areas in Iran are Kashan, Fars, Kerman and Azerbaijan. Kerman province with 2297 hectares ha of rose gardens and 6198 tons of flower production is one of the important rose production regions. The productions of this region are organic and do not use anychemical compounds such as pesticides and fertilisers. The major fungal pathogens were studied during 2008–2010 in oil rose production areas in Kerman province, Iran. Verticillium dahlias, Rosellinia necatrix, Alternaria alternata, Seimatosporium fusisporum and Podosphaera pannosa have been detected in the oil rose from different regions in Kerman province. A. alternata has the most isolates and infected plants per cent in the oil rose. This is the first report fromVerticillium dahliae, R. necatrix, A. alternata, S. fusisporum on oil roses (R.damascena) in the world.  相似文献   

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