Efficacy of Talaromyces flavus Alone or in Combination with other Antagonists in Controlling Verticillium dahliae in Growth Chamber Experiments

Abstract

Talaromyces flat-US reduced viability of microsclerotia of Verticitlium dahliae on senescent potato stems collected from the field when applied as ascospores in carboxymethylcellulose or in talcum powder. Incorporating an alginate wheat-bran preparation of T. fiavus in soil at a rate of 0.5% (w/w) was followed by a decrease of >90% of the population of V. dahliae in soil at both 15 and 25 C. Population densities of V. dahliae were negatively correlated (r = -0.50; P = 0.001) with those of T.flavus. However, the population of V. dahliae was also reduced in soil with alginate wheat-bran alone. When incorporated in soil in alginate wheat-bran and simultaneously coated on seeds in ti^lcum powder. T. flavus reduced colonization of roots and infection of eggplants by K. dahliae. Although to a lesser extent than with the antagonist, alginate wheat-bran without T. flavus also reduced infection by the pathogen. Treatment with combinations of T. flavus with other biocontrol agents, viz. Bacillus subtilis, Fusarium oxysporum or Gliocladium roseum, containing half of the inoculum of the single application of each antagonist, gave similar control of root colonization and stem infection by V. dahliae as application of the single antagonists. Population densities on the root of each antagonist were not or only slightly affected by the presence of the co-inoculated antagonist suggesting that the combinations were compatible. ZusammenfassungWirkung voo Talaromyces flavus allein oder in Kombination mit anderen Antagonisten bei der Bekampfung von VerticUUum dahliae in Klimakammerversuchen Talaromyces flavus verdngerte die Lebensfahigkeit von Microsclerotien des Pilzes Verticillium dahliae an seneszenten, auf dem Feld gesammelten Kartoffeltrieben, wenn Ascosporen des Antagonisten in Carboxymethylcellulose oder Talkumpuder angewendet wurden. Auf die Einarbeitung eines Alginat-Weizenkleie-Praparats von T. flavus in den Boden (0,5% (w w) folgte eine mehr als 90%-ige Abnahme der V. (/a/i/iOf-Population im Boden, sowohl bei 15 C als auch bei 25 C. Die Populationsdichten von V. dahliae waren mit denjenigen von T. flavus negativ korreliert (r = -0,50; P = 0,001). Die V. dah-

Desirable Traits of a Good Biocontrol Agent against Verticillium Wilt

“…Different formulations of T. flavus were tested (Nagtzaam et al, 1998; Zeise and Kersten, 2000), but up to date none of them have been registered in the European Union (http://ec.europa.eu/food/plant/pesticides). …”

Diversity, Pathogenicity, and Management of Verticillium Species

“…abound in the literature (54,55,100,144), but few have developed into products with field-level efficacy. Successful biocontrol agents at the field scale need to satisfy all of the following criteria: (a) reduce microsclerotia in the soil bank; (b) reduce incidence of Verticillium wilt on the crop; (c) improve yields of infected plants to levels comparable with healthy plants or crops grown in fumigated soils.…”

Verticillium wilt of olive: a case study to implement an integrated strategy to control a soil-borne pathogen

“…On the other hand, while studies on biological control of Verticillium wilts are available, they are again focused in herbaceous hosts and in just a small number of soil-borne fungi (i.e., Talaromyces, Trichoderma) or bacteria (i.e. Bacillus, Paenibacillus, Pseudomonas, Serratia, Streptomyces) species which have so far been demonstrated to be effective BCA against V. dahliae (Jordan and Tarr 1978;Leben et al 1987;Berg et al 1994;Madi et al 1997;Alström 2001;Nagtzaam et al 1998;Narisawa et al 2002;Tjamos et al 2004Tjamos et al , 2005Antonopoulos et al 2008;Uppal et al 2008;Erdogan and Benlioglu 2010;Meschke and Schrempf 2010). Finally, arbuscular mycorrhizal fungi (i.e.…”