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Alternaria tenuissima was isolated from tomato showing symptoms of leaf spot disease cultivated under greenhouse conditions from Asir region, Saudi Arabia. The ability of salicylic acid (SA) and the newly prepared bioactive matter "Agrileen" (AG) to suppress the leaf spot disease of tomato was evaluated. Exogenous application of SA (0.5 and 1.0 mM) or AG (2.5 and 5%) enhanced the growth and plant yield of tomato in addition to the reduction of infection with A. tenuissima. Photosynthetic pigments, total proteins, free proline and the relative water content of leaves were also enhanced when either SA or AG was applied. The protein pattern showed an increase in band intensity in plants treated with SA that express the increase in gene expression involved in resistance against stress conditions. The results confirmed that the application of SA or AG could protect tomato plants against A. tenuissima infection either through the direct strength of the defense system and a reduction of the severity of the pathogen. [ABSTRACT FROM AUTHOR]

Isolation and identification of the indigenous yeasts of the rotten date fruits for possible production of bioethanol and single-cell protein was the aim of this study. Results showed that a considerable amount of date fruits is subjected to unfavorable conditions of storage that induce their rot and spoilage. From the rotten date fruits, ten yeast isolates were obtained and genetically identified by the sequence of D1/D2 domain of the 26S rRNA gene and phylogenetic analysis. The identity of these yeasts was: Hanseniaspora guilliermondii, H. uvarum (2 strains), H. opuntiae, Pichia kudriavzevii (2 strains), Issatchenkia orientalis, Wickerhamomyces anomalus, Yarrowia lipolytica and Zygosaccharomyces rouxii. The ability of these strains to ferment 20% of the spoilage date fruit juice evaluated on laboratory scale. Results proved that P. kudriavzevii KKUY-0151 and H. uvarum KKUY-0153 yielded 67.48 and 67.37 g/L respectively, of bioethanol as the highest producers. However, H. uvarum KKUY-0078, H. guilliermondii KKUY-0009 and Z. Rouxii KKUY-0157 produced the highest fresh biomass weight 31.76, 30.96 and 30.69 g/L, respectively as a single cell protein production. The study is a pioneer to investigate the endemic yeasts of the rotten date fruits. It concludes that some of the indigenous yeasts of the rotten date fruits are promising organisms in recycling the substrate into valuable products such as bioethanol and single-cell protein. © 2014 Friends Science Publishers [ABSTRACT FROM AUTHOR]