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Copyright of Revista Mexicana de Ciencias Agrícolas is the property of Instituto Nacional de Investigaciones Forestales, Agricolas y Pecuarias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fungal diseases represent one of the causes of annual crop losses. Rhizoctonia solani is a pathogenic fungus with worldwide distribution associated with root and tuber diseases of different crops; it causes important economic losses in perennial and annual plants, including almost all horticultural crops. To mitigate losses due to fungus, fungicides of synthetic origin have been used; however, many of these substances are associated with carcinogenicity and are toxic to the environment. Edible macromycete mushrooms are a source of antifungal compounds to control diseases in agricultural crops. This work evaluated the antifungal activity of extracts of edible mushrooms (Lactarius deliciosus, Ustilago maydis, Amanita jacksonii and Amanita rubescens) against the phytopathogen R. solani by means of three techniques: diffusion of wells, discs and plate dilution. The results show that with the diffusion of wells, no effect was observed on the growth of R. solani with the alcoholic extracts and their dilutions. While with disc diffusion, a qualitatively slower growth was observed compared to the controls of R. solani with the ethanolic extract of A. jacksonii and in its 1:1 dilution of methanol-water. In the plate dilution, it was found that the 1:1 ethanol water dilution of L. deliciosus had 88% inhibition on the growth of R. solani, followed by the ethanol extract of L. deliciosus (65%), methanol extract from U. maydis (63%) and methanol extract from L. deliciosus (57%). Therefore, the extracts and the dilution must be studied in greater depth, by being tested in an in vivo system and identifying the secondary metabolites present. [ABSTRACT FROM AUTHOR]

Copyright of Informacion Tecnica Economica Agraria is the property of Asociacion Interprofesional para el Desarrollo Agrario (AIDA) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Poblano chili (Capsicum annuum L.) is a widely consumed variety in our country, but there are several problems that affect its cultivation and production. Considering the above, the objective of this research was to elaborate and compare the effect of two biofertilizers with rhizobacteria on the growth of Poblano chili seedlings. The research was conducted at the Postgraduate College, Montecillo Campus in the years 2015-2016. The work was carried out in three stages: 1) selection of culture media and growth dynamics of four strains of rhizobacteria; 2) elaboration of two bioformulations using alginate and peat pearls as carriers; also, the viability of the rhizobacteria was evaluated for five months; and 3) evaluation of the effect of bioformulations in promoting the growth of Poblano chili seedlings. Serratia strains showed the highest growth in the TBS culture medium, while Pseudomonas strains had high growth in Luria-Bertani broth. The stationary phase of the Pseudomonas strains was reached between 24-48 h and that of the Serratia strains between 12-44 h. The shelf life of the two formulations was maintained from 1 x 1012 to 1 x 109 CFU for five months. The application of alginate beads in the seedlings stimulated seedling growth up to 35% with respect to the control. The application of biofertilizers based on alginate and peat pearls is a good option to promote the growth of chili seedlings. [ABSTRACT FROM AUTHOR]

This work assessed the ability of Lolium perenne and Medicago sativa for extracting lead (Pb) from particulate printed circuit computer boards (PCB) mixed in sand with the following concentrations: 0.5, 1.0 and 1.5 g of PCB, and including a control treatment without PCB. The PCB were obtained from computers, and grinded in two particle sizes: 0.0594 mm (PCB1) and 0.0706 mm (PCB2). The PCB particle sizes at their corresponding concentrations were applied to L. perenne and M. sativa by using three experimental assays. In assay II, PCB2 affected the biomass production for both plants. For assay III, the PCB1 increased the biomass of M. sativa (236.5%) and L. perenne (142.2%) when applying either 0.5 or 1.0 g, respectively. In regards to phytoextraction, assay I showed the highest Pb-extraction by roots of L. perenne (4.7%) when exposed to 1.5 g of PCB1. At assay I, L. perenne showed a Pb-bioconcentration factor higher than 1.0 when growing at 0.5 g of PCB1, and when HNO3 was used as digestion solution; moreover, in assay III both plants showed a Pb-translocation factor higher than 1.0. Therefore, Lolium perenne and Medicago sativa are able to recover Pb from electronic wastes (PCB). [ABSTRACT FROM AUTHOR]

Oleaginous microorganisms such as microalgae, yeasts, bacteria and filamentous fungi are alternative sources of vegetal or animal fats for biodiesel production. This research evaluated the lipid production by the biomass Trichoderma koningiopsis MX1 with a non-stirring culture at room temperature, and fungal lipids were extracted through three techniques for biodiesel generation purposes. The three modified lipid extraction techniques yielded 18.4, 10.3 and 17.1 % of fungal lipids. The trans-esterification of lipids indicated that the controlling components for biodiesel were palmitic (40.8 %) and linoleic acids (ranging from 37.6 % to 41.2 %). Results show that fungal cultural conditions and the lipid extraction technique are determinants for producing biodiesel from fungal lipids. Therefore, the modification of some of these conditions could increase their efficiency and viability. [ABSTRACT FROM AUTHOR]

RNA isolation is essential to study gene expression at the molecular level. However, RNA isolation is especially difficult in organisms such as filamentous fungi which contain compounds that bind and/or co-precipitate with RNA. No commercial kit is yet available for the isolation of high-quality RNA from these organisms. Furthermore, because of the large amounts of polysaccharides, the common protocols for RNA isolation usually result in poor yields when applied to Trichoderma. A simple and fast protocol for the isolation of RNA with high yields that effectively remove contaminating substances is introduced here. The protocol is based on the SDS/phenol cellular sample treatment method, with the following modifications: a phenol/chloroform extraction step for removal of proteins, DNA, and polysaccharides by precipitation without β-mercaptoethanol and liquid nitrogen. This procedure may be useful for the isolation of RNA from other filamentous fungi and may serve as an important tool for the molecular analysis of these organisms. [ABSTRACT FROM AUTHOR]

Oleaginous microorganisms such as microalgae, yeasts, bacteria and filamentous fungi are alternative sources of vegetal or animal fats for biodiesel production. This research evaluated the lipid production by the biomass Trichoderma koningiopsis MX1 with a non-stirring culture at room temperature, and fungal lipids were extracted through three techniques for biodiesel generation purposes. The three modified lipid extraction techniques yielded 18.4, 10.3 and 17.1 % of fungal lipids. The trans-esterification of lipids indicated that the controlling components for biodiesel were palmitic (40.8 %) and linoleic acids (ranging from 37.6 % to 41.2 %). Results show that fungal cultural conditions and the lipid extraction technique are determinants for producing biodiesel from fungal lipids. Therefore, the modification of some of these conditions could increase their efficiency and viability.