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Growers have adopted monoculture to maintain the high melon (Cucumis melo L.) production demand in the Northeastern region of Brazil. This cultivating practice culminates in up to three crop cycles per year being used in the same growing area. The main objective of this study was to evaluate if the incorporation of plant material used with polyethylene mulch and or in association with commercial soil amendment products can help to condition an environment that is beneficial to soil microbial communities. Two identical greenhouse experiments were conducted using a completely randomized design with seven treatments and seven replications. The treatments were: (C) – Control, (M) - polyethylene mulch, (C+M) - incorporation of Crotalaria juncea L. + polyethylene mulch, (P+M) - incorporation of Pennisetum glaucum L. + polyethylene mulch, (M+CS) - polyethylene mulch + (Compost-Aid® + Soil-Set®, trade names of products produced by Alltech Crop Science), (C+M+CS) - incorporation of C. juncea L. + polyethylene mulch + (Compost-Aid® + Soil-Set®), and (P+M+CS) - incorporation of P. glaucum L. + polyethylene mulch + (Compost-Aid® + Soil-Set®). To quantify the target soil microbiota (fungi, bacteria, sporulating bacteria, and actinomycetes), isolations were attempted on selective culture media specific for each group of microorganisms. The incorporation of P. glaucum together with the use of polyethylene mulch and commercial products (Compost-Aid® and Soil-Set®), (P+M+CS), increased the total fungal population by 183%, total bacteria by 55%, sporulating bacteria by 21%, and actinomycetes by 146% in relation to the control treatment. RESUMO Os produtores há anos adotam a monocultura para manter a demanda de produção de melão alto (Cucumis melo L.) na região Nordeste do Brasil. Esta estratégia de cultivo é usada em até três ciclos por ano. O objetivo principal deste estudo foi avaliar se a incorporação de material vegetal utilizado com mulch de polietileno e/ou em associação com produtos corretivos de solo pode condicionar um ambiente benéfico para as comunidades microbianas do solo. Dois experimentos idênticos em casa de vegetação foram conduzidos em um delineamento inteiramente casualizado com sete tratamentos e sete repetições. Os tratamentos foram: (C) – Controle, (M) - cobertura de polietileno, (C+M) - incorporação de Crotalaria juncea L. + cobertura de polietileno, (P+M) - incorporação de Pennisetum glaucum L. + cobertura de polietileno, (M+CS) - cobertura de polietileno + (Compost-Aid® + Soil-Set®, nomes comerciais dos produtos produzidos pela Alltech Crop Science), (C+M+CS) - incorporação de C. juncea L. + cobertura de polietileno + (Compost-Aid® + Soil-Set®) e (P+M+CS) - incorporação de P. glaucum L. + cobertura de polietileno + (Compost-Aid® + Soil-Set®). Para quantificar a microbiota do solo (fungos, bactérias, bactérias esporulantes e actinomicetos), foram realizados isolamentos em meios de cultura seletivos para cada grupo de microrganismos. Conclui-se que, coletivamente, a incorporação de P. glaucum juntamente com o uso de mulch de polietileno e os produtos comerciais (Compost-Aid® e Soil-Set®), aumentou a população total de fungos em 183%, bactérias totais em 55%, bactérias esporulantes em 21% e actinomicetos em 146% em relação ao tratamento controle.

Flooding of sweetpotatoes in the field leads to development of soft rot on the storage roots while they remain submerged or on subsequent harvest and storage. Incidences of flooding after periods of intense rainy weather are on the rise in the southeastern United States, which is home to the majority of sweetpotato production in the nation. In an effort to characterize the causative agent(s) of this devastating disease, here we describe two distinct bacterial strains isolated from soft-rotted sweetpotato storage roots retrieved from an intentionally flooded field. Both of these anaerobic spore-forming isolates were identified as members of the genus