Inoculation of arbuscular mycorrhizal fungi as a strategy to improve annatto (Bixa orellana L. ) growth

This study aimed to assess the occurrence of arbuscular mycorrhizal fungi (AMF) in annatto (Bixa orellana L.) cultivars and their response to AMF inoculation using biometric parameters. The occurrence surveys were conducted in annatto fields in three municipalities from Pernambuco Forest Zone: Lagoa de Itaenga, Gloria de Goitá, and Vitoria de Santo Antão, and in four cultivars (Red Piave, Green Piave, Red Peruvian Paulista, and Green Peruvian Paulista). In a greenhouse, biometric parameters of annatto seedlings of Red Piave, Red Peruvian Paulista, Embrapa-36, and Embrapa-37 cultivars inoculated with AMF isolated from annatto fields. The Red Piave cultivar exhibited greater root colonization than the Green Peruvian Paulista in the Lagoa de Itaenga and Vitoria de Santo Antão municipalities. The cultivar Red Piave showed a more beneficial association with AMF in plants and soil than cultivar Green Peruvian Paulista did, in both Lagoa de Itaenga and Vitoria de Santo Antão. AMF inoculation was effective in promoting the growth of annatto plants, particularly those inoculants with S. heterogama and C. etunicatum.

Identificação de bactérias diazotróficas isoladas em cultivares de palma (Opuntia e Nopalea) usando o gene recA / Identification of diazotrophs isolated from palm cultivars (Opuntia and Nopalea) using the recA gene

Este trabalho teve como objetivo caracterizar filogeneticamente os isolados bacterianos da cultura da palma forrageira usando o gene recA. Para o isolamento caldódios de palma foram maceradas e inoculadas em meios semissólido semi-seletivo NFb, JNFb, LGI e LG sem adição de nitrogênio. Foram obtidos doze micro-organismos cuja a analise parcial do gene recA possibilitou a identificação dos gêneros Azospirillum, Bacillus e Methylobacterium.. Bactérias diazotróficas encontrados na cultura da palma podem ter uma grande função como bactéria promotora de crescimento. O gene recA mostrou-se bastante consistente para uso em filogenia molecular de bactérias. Observou-se ainda a presença de bactérias destes gêneros podem ter de grande interesse para futuros estudos considerando seu alto poder biotecnológico.

This study aimed to characterize phylogenetically isolated bacterial culture of Cactus Pear using the parcial gene recA. For isolation cladodes were macerated and inoculated in semi-selective semisolid media NFB, JNFb, LGI and LG without added nitrogen. Twelve micro-organisms were obtained whose analysis of partial gene recA enabled the identification of the genera Azospirillum, Bacillus and Methylobacterium. Diazotrophic bacteria found in the culture of Cactus Pear may have a great function as growth-promoting bacteria. The partial gene recA was shown to be quite consistent for use in molecular phylogeny of bacteria. We also observed the presence of bacteria of these genera may be of great interest for future studies considering its high power biotechnology.

Triple inoculation with Bradyrhizobium, Glomus and Paenibacillus on cowpea (Vigna unguiculata) [L. ] walp. )development. (au)

The use of microorganisms to improve the availability of nutrients to plants is of great importance to agriculture. This study aimed to evaluate the effect of triple inoculation of cowpea with arbuscular mycorrhizal fungi (AMF), plant growth-promoting bacteria (PGPB) and rhizobia to maximize biological nitrogen fixation (BNF) and promote plant growth. The experiment was conducted in a greenhouse using cowpea plants (Vigna unguiculata L. Walp cv. IPA 206). The treatments included inoculation with strains of Bradyrhizobium sp. (BR 3267 and EI - 6) individually and as a mixture, an absolute control (AC) and mineral nitrogen control (NC), all combined with the presence or absence of native AMF (Glomus etunicatum) and PGPB (Paenibacillus brasilensis - 24) in a 5x2x2 factorial design. All treatments were replicated three times. Contrasts were performed to study the treatment of variables. Inoculation with Bradyrhizobium sp. (BR 3267 and EI - 6) and G. etunicatum favored nitrogen acquisition and phosphorus availability for the cowpea plants. Inoculation with P. brasilensis - 24 increased colonization by Bradyrhizobium sp. and G. etunicatum and promoted cowpea growth, while the nitrogen from symbiosis was sufficient to supply the plants nutritional needs.