Evaluation of biological control agents for managing cucurbit powdery mildew on greenhouse‐grown melon

Abstract

An evaluation was made of the ability of two mycoparasite-based products AQ10® ( Ampelomyces quisqualis ) and Mycotal® ( Lecanicillium lecanii ), as well as three strains of Bacillus subtilis , to manage powdery mildew disease, caused by Podosphaera fusca on melon seedlings maintained under different regimes of relative humidity and on plants grown under greenhouse conditions in Spain. In every case fungal and bacterial biocontrol agents (BCAs) performed better under conditions of high relative humidity (90-95% RH). In greenhouse experiments, the effectiveness of the mycoparasites to manage powdery mildew was absolutely dependent on mineral oil. The strains of B. subtilis provided disease control similar to that achieved with the mycoparasites or the fungicide azoxystrobin. Microscopic analysis showed the ability of these bacterial strains to efficiently colonize leaf surfaces and revealed the occurrence of antagonistic interactions between biological agents and P. fusca structures. These results confirmed the usefulness of these BCAs for managing powdery mildew on greenhouse-grown cucurbits either as single products or as a component of integrated control programmes.

Screening of alternative products for integrated pest management of cucurbit powdery mildew in Sweden

“…AQ10, formulated from the hyperparasitic fungus Ampelomyces quiscalis and applied with the paraffin based additive Bioglans was included in the short-term experiment 1 (Table 4) and had a suppressive effect significantly different from the controls but was less efficient than Fungazil. A. quiscalis, which is a well-known mycoparasite of CPM, is often found to co-occur at the same site as CPM fungi, and has previously been shown to be an effective treatment against some CPM fungi (Elad et al 1998;Sedlakova and Lebeda 2010;Romero et al 2007;Kristkova et al 2009). Our results are in line with previous reports on the highly variable effect of P. oligandrum and A. quiscalis, often explained by their demands for high humidity or commercial formulation issues (Giotis et al 2012;Benhamou et al 1999).…”

Bacillus-Based Biological Control of Plant Diseases

“…(Sivakumar et al, 2007) Mango Oidium mangiferae (Nofal & Haggag, 2006) Mellon Podosphaera fusca (Romero et al, 2007b) Mustard Alternaria brassicae (Sharma & Sharma, 2008) Nectarine Monilinia laxa (Casals et al, 2010) Oilseed rape Sclerotinia sclerotiorum (Hu et (Salerno & Sagardoy, 2003) Tobacco R. solanacearum (Maketon et al, 2008) Tomato Xanthomonas euvesicatoria Xanthomonas perforans (Roberts et al, 2008) Nematodes Tomato Meloidogyne (Araújo & Marchesi, 2009) (Siddiqui & Futai, 2009) …”

Preventative and Curative Effects of Several Plant Derived Agents Against Powdery Mildew Disease of Okra

“…There are public attitudes and environmental concerns towards the use of fungicides (Belanger and Benyagoub, 1997;Whipps and Lumsden, 2001), as well as occurrence of new strains resistant to different fungicides (Moustafa et al, 1990;ƠBrien, 1994). Use resistant or tolerant cultivars have been developed in many crops, but it is also limited especially in vegetable crops (Kiss, 2003;Romero et al, 2007). For instance, in other important crops such as tomato and cucumber most cultivars available to growers worldwide are susceptible (Kiss et al, 2001;Kiss, 2003;Konstantindou-Doltisinis et al, 2006).…”