Omar Romero Arenas

Evaluation of Substrates in the Elaboration of Secondary Inoculum for the Cultivation of Pleurotus ostreatus

The preparation of spawn or inoculum and its subsequent cultivation form the first step in the oyster mushroom supply chain, the preparation of the inoculum is related to quality parameters in the edible fungi production, where the use of grains of different cereals is essential to obtain the spawn The aim of this study was to determine the quality of different formulations of spawn using grains as wheat, corn, rice and sorghum furthermore, the growth of the strain of the CP-50 of Pleurotus ostreatus for oyster mushroom production on barley straw, under rustic conditions. In the spawn colonization and the percentage of contamination statistically significant differences were observed (P <0.05), being the treatments based on sorghum in combination with wheat, corn and rice the first to complete this process without presenting an incidence of competing organisms. Regarding yield and biological efficiency, no statistically significant differences (P <0.05) were found when using different formulations of spawn, values ranging from 84.17% were observed for fructification with the wheat + rice formulation, up to 71.45% when the formulation of spawn based on sorghum + corn was used. The production cycles had a variation of up to ten days between treatments, obtaining a more cut cycle when the sorghum + corn formulation was used. The results suggest the feasibility of using lower cost grains such as sorghum which impact in this process translates into a better cost benefit relation for small producers.

Diversidad de Vanilla spp. (Orchidaceae) y sus perfiles bioclimáticos en México

The genus Vanilla comprises around 110 species distributed throughout Earths tropical regions, with the largest number of reported species growing in the American continent. Vanilla farming is associated with many Mexican cultures such as the Totonac, Mayan, Chinantec, and Mazatec, among others. Currently, this crop is threatened by technical, social, ecological, and climatic conditioning factors, limiting its production and the preservation of wild and cultivated species. It is therefore necessary to ascertain the current diversity status of each of these species, as well as some of their main bioclimatic profile indicators, in order to help decision-making, aimed at preserving and genetically improve these species. During 2008, we gathered data from IPN, MEXU, and XAL herbaria, as well as from CONABIO’s World Information Network on Biodiversity (REMIB), the Global Biodiversity and Information Facility (GBIF), and we also used data from live access to BUAP’s vanilla germplasm bank, obtained between 2008 and 2014. Distribution maps were generated using a geographical information system. Bioclimatic profiles for each species were obtained considering 19 WorldClim variables and altitude at a spatial resolution of approximately 1 Km2. Variance, Mean, and standard deviation for each of the 19 variables were calculated at each of the registered points. Extreme environmental condition intervals (minimum, average, and maximum) were also obtained. In order to determine the most important distribution variables of the species, we performed a principal component analysis and carried out Kruskal-Wallis and Dunns tests on the variables identified as significant. Results indicated records for V. planifolia, V. pompona, V. insignis, V. inodora V. odorata, V. cribbiana, and V. sprucei in Mexico, distributed throughout nine states in the country. V. planifolia presented wide intervals of temperature and rain precipitation, while V. pompona, V. odorata, V. insignis and V. inodora presented intermediate intervals. The amplitudes of extreme data for each species can be considered in locating areas where ex situ regional preservation strategies could be put in place, as well as in establishing areas for cultivation. The bioclimatic profile we found, allows for an indirect inference of each species’ genetic condition, which could be used in genetic improvement programs; for instance, V. odorata grows at high altitudes and tolerates low temperatures, while V. inodora tolerates high temperatures, and V. odorata, V. pompona and V. planifolia tolerate low rain precipitation.