Combination of hot water, Bacillus subtilis CPA-8 and sodium bicarbonate treatments to control postharvest brown rot on peaches and nectarines

Abstract

The aim of this study was to evaluate the effect of hot water (HW), antagonists and sodium bicarbonate (SBC) treatments applied separately or in combination to control Monilinia spp. during the postharvest storage of stone fruit. Firstly, we investigated the effect of HW temperatures (55-70°C) and exposure times (20-60 s), seven antagonists at two concentrations (10 7 or 10 8 cfu ml −1 ) and four SBC concentrations (1-4%). The selected treatments for brown rot control without affecting fruit quality were HW at 60°C for 40 s, SBC at 2% for 40 s and the antagonist CPA-8 (Bacillus subtilis species complex) at 10 7 cfu ml −1 . The combinations of these treatments were evaluated in three varieties of peaches and nectarines artificially inoculated with M. laxa. When fruit were incubated for 5 d at 20°C, a significant additional effect to control M. laxa was detected with the combination of HW followed by antagonist CPA-8. Only 8% of the fruit treated with this combination were infected, compared to 84%, 52% or 24% among the control, CPA-8, and HW treatments, respectively. However, the other combinations tested did not show a significant improvement in effectiveness to control brown rot in comparison with applying the treatments separately. When fruit were incubated for 21 d at 0°C plus 5 d at 20°C, the significant differences between separated or combined treatments were reduced and generally the incidence of brown rot was higher than when fruit were incubated for 5 d at 20°C. Similar results were observed testing fruit with natural inoculum.

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) …”

Storage behavior of mango as affected by post harvest application of plant extracts and storage conditions

“…For the last few years the post harvest application of various fungicides, growth regulators and waxing materials have gained popularity among growers, to enhance the shelf life of fruits. However, owing to increased resistance of some post harvest fungal pathogens against authorized fungicides (Reimann and Deising 2000;Dianz et al 2002), their residual toxicity, environmental pollution and their side effects on human health (Lingk 1991;Unnikrishnan and Nath 2002) there has been increased efforts to develop alternative control measures (Smilanick et al 2008;Droby et al 2009;Casals et al 2010). Extracts obtained from plants have recently gained popularity and scientific interest for their antibacterial and antifungal activity (Lee et al 2007;Santas et al 2010).…”

Controle em pós-colheita de Penicillium digitatum EM laranja-pera com microrganismos e tratamento térmico

“…Obagwu e Korsten (2003) verificaram que a redução da incidência dos bolores verde e azul foi obtida com a adoção do tratamento térmico (45 ºC por 2 minutos), seguido do tratamento com B. subtilis (F1, L2 ou L2-5). A associação de tratamento térmico (60 ºC por 40 segundos) com B. subtilis (CPA-8) apresentou sinergismo no controle de Monilinia laxa em pêssegos incubados por cinco dias a 20 ºC (CASALS et al, 2010).…”