La inoculación con hongos micorrízicos arbusculares ha permitido un desarrollo y crecimiento controlado en especies hortícolas; sin embargo, no se ha evaluado su efecto en algunos cultivos ornamentales tropicales como las heliconias. El objetivo fue evaluar la aplicación de hongos micorrízicos arbusculares (HMA) en el desarrollo de Heliconia stricta, teniendo como hipótesis general que el uso de HMA incrementa la absorción de nutrientes como nitrógeno, fósforo, potasio y favorecer su aclimatación y crecimiento. Se evaluó el desarrollo fisiológico de las plantas de H. stricta como respuesta a su inoculación con cuatro HMA: Rhizophagus intraradices, Zac-19, mezcla de cepas e inóculo nativo en México. Se determinó la altura de las plantas, número de brotes, tasa fotosintética con un analizador de fotosíntesis IRGA, LI-COR 6400XT y colonización micorrízica por el método de Phillips y Hayman. Los resultados evidenciaron incrementos estadísticamente significativos por efecto del inóculo no nativo, en la altura de la planta, el número de brotes por planta, la tasa fotosintética y la colonización micorrízica (p≤ 0.05). El inóculo nativo produjo efectos estadísticamente significativos en la colonización de las raíces (p≤ 0.05). Se concluye que existe un efecto benéfico estadísticamente significativo (p≤ 0.05) de la inoculación micorrízica sobre el crecimiento de las plantas debido a su mayor altura, número de brotes por planta y tasa fotosintética.

Livestock systems can contribute to food security by making use of available resources not suitable for human consumption such as Cucurbita argyrosperma Huber residue (CR). The aim of this pilot study was to evaluate preference and physicochemical characteristics of CR silages and their effect on milk production and milk composition from cows in a dual-purpose system in Campeche, Mexico. Three completely randomized experiments were performed. In experiment 1, physicochemical characteristics of four CR plus hay grass silages were evaluated: CR-77, CR-71, CR-65 and CR-59, containing 77%, 71%, 65% and 59% of CR, with 25%, 30%, 35% and 40% of estimated dry matter (DM), respectively. In experiment 2, silages intake preferences were determined in cattle. In experiment 3, the effect of CR silage or corn silage on milk production and milk composition of grazing cows in a dual-purpose system was evaluated. The results in experiment 1 showed that DM content differed between treatments (p < 0.05), ranging from 27.35% (CR-77) to 41.81% (CR-59) and estimated DM was similar to the actual values. pH and temperature were also different (p < 0.05). pH was different between CR-71 (4.01) and CR-59 (4.43), and temperature between CR-77 (28.87 °C) and CR-65 (29.5 °C). Crude protein (CP) was very low in all silages (<4%), particularly in CR-59 (2.8%) (p < 0.05), and neutral detergent fiber (NDF) was significantly (p < 0.05) higher with CR-65 and CR-59 (average: 79.6%) than CR-77 and CR-71 (average 75.1%). There were no differences in intake preference (experiment 2), milk production (average 3.7 L) or milk composition (average protein: 3.27%, fat: 2.26%, lactose: 5.23%, solids non-fat: 9.17%) (experiment 3) (p > 0.05), but differences in DM intake of silages in experiment 3 were observed (p < 0.05). Even with the limitations of this pilot study, it is feasible to produce silages with CR with a good fermentation process as a feeding alternative for cows in a dual-purpose system in Campeche, Mexico.

No abstract

Estudio preliminar sobre la inhibición in vitro de nematodos gastrointestinales de ovinos con extractos acuosos de plantas forrajeras