Charcoal rot is an emerging disease for peanut crops caused by the fungus Macrophomina phaseolina. In Mexico, peanut crop represents an important productive activity for various rural areas; however, charcoal rot affects producers economically. The objectives of this research were: (a) to identify and morphologically characterize the strain “PUE 4.0” associated with charcoal rot of peanut crops from Buenavista de Benito Juárez, belonging to the municipality of Chietla in Puebla, Mexico; (b) determine the in vitro and in vivo antagonist activity of five Trichoderma species on M. phaseolina, and (c) determine the effect of the incidence of the disease on peanut production in the field. Vegetable tissue samples were collected from peanut crops in Puebla, Mexico with the presence of symptoms of charcoal rot at the stem and root level. The “PUE 4.0” strain presented 100% identity with M. phaseolina, the cause of charcoal rot in peanut crops from Buenavista de Benito Juárez. T. koningiopsis (T-K11) showed the highest development rate, the best growth speed, and the highest percentage of radial growth inhibition (PIRG) over M. phaseolina (71.11%) under in vitro conditions, in addition, T. koningiopsis (T-K11) showed higher production (1.60 ± 0.01 t/ha⁻¹) and lower incidence of charcoal rot under field conditions. The lowest production with the highest incidence of the disease occurred in plants inoculated only with M. phaseolina (0.67 ± 0.01 t/ha⁻¹) where elongated reddish-brown lesions were observed that covered 40% of the total surface of the main root.

Strawberry wilt is a disease caused by Fusarium solani, which it provokes the death of the plant. Farmers mainly use chemical methods for its control, which has a negative impact on the environment and human health. Given the growing demand for organic agricultural products, compatible alternatives must be sought for disease management that can reduce the doses of fungicides. A combination of pesticides and biological control agents could be an alternative for the management of F. solani. Consequently, investigations on fungicide compatibility and synergistic effects are recommended in relation to the biological control of strawberry wilt. In this study, potential antagonism was calculated according to the class of mycoparasitism and the percentage inhibition of radial growth in order to later design a compatibility model of the different species of Trichoderma with three protective fungicides at different concentrations. The potential antagonism showed that Trichoderma asperellum presented high compatibility with the fungicides Captan and Mancozeb added in concentrations of 450, 900, and 1350 mg L⁻¹. The use of antagonistic strains together with the fungicide Chlorothalonil in its three concentrations showed a negative effect on the growth of Trichoderma species, which caused low and null compatibility against the MA-FC120 strain of F. solani in vitro.

Diversity of the different types of chilies in Mexico has been scarcely studied, and a large variety have been found to be, such as Manzano chili. Root rot caused by oomycete Phytophthora capsici is a severe disease that affects Manzano chili production in Mexico, detracted from its production and quality. The use of biological control agents such as Trichodermanative’s species, represents an efficient alternative to reduce losses and control the disease. For this reason, the objective of the present investigation was to evaluate the antagonistic effect in vitro and in vivo of four native strains of Trichoderma spp., on Phytophthora capsici in seedlings of Manzano chili from Puebla-Mexico was evaluated. Dual culture technique was used to determine the percentage of inhibition of radial growth (PICR) of the PC-A strain of P. capsici. Analysis of the percentage of germination was also carried out, as well as the incidence of root rot at 20 days after inoculation with the pathogen (dai) in the nursery. T. harzianum strain presented the highest PICR (42.86%) of antagonistic level in vitro and class I in the Bell scale, in addition, it obtained 88% germination in the nursery and 10% mortality at 20 dai, higher than the other native strains of Trichoderma. The bio-controlling effect of strains of Trichoderma spp., offers an effective alternative for root necrosis caused by P. capsici in the cultivation of Manzano chili in Puebla-Mexico.

Birth weight (BW) and weaning weight (WW) data from Pelibuey and Blackbelly lambs belonging to the Asociación Mexicana de Criadores de Ovinos (AMCO) were used with the objective of estimating genetic parameters (heritability and genetic correlations) and analyzing the growth characteristics of ewes born and weaned at different times of the same year from different herds with pedigree registration. In the case of Pelibuey lambs, the animal model included the weaning weight at 75 days of age, considering the direct additive genetic effect, maternal additive genetic effect, covariance between direct and maternal effects, as well as the permanent environmental effect of the mother. The direct estimators of heritability for Pelibuey were BW = 0.01 ± 0.021 and WW = 0.31 ± 0.074 and for Blackbelly they were BW = 0.05 ± 0.042 and WW = 0.41 ± 0.146. In the case of the maternal heritability estimators in Pelibuey they were BW = 0.02 ± 0.040 and WW = 0.21 ± 0.121 and for Blackbelly they were BW = 0.12 ± 0.054 and WW = 0.28 ± 0.121. The magnitude of the estimates of genetic correlations between direct and maternal effects for adjusted weaning weight at 75 days of age indicate that genetic progress may be slow in a breeding program. However, these selection results could be included in the short term in the breeding programs for the Pelibuey and Blackbelly breeds in Mexico, for livestock development in low-income rural areas.

The problems and limitations of the control of diseases caused by phytopathogens through the use of fungicides, make the biological control present as an alternative method in the production of tomato plants in greenhouse, which is limited by the incidence of Fusarium oxysporum Schlechtend.:Fr., being the most worldwide destructive disease. The objective of the present investigation was to evaluate the effect of three Mexican strains of the genus Trichoderma against F. oxysporum on the production of tomato seedlings under greenhouse conditions, as well as to determine the antagonistic effect of the strains used. The Trichoderma harzianum strain had the highest antagonistic activity (81.50%) and the highest growth rate (1.25 cm/day), proving to be the most aggressive strain to control F. oxysporum. in addition the results of the interaction of the dual cultures paired, presented a visible overgrowth zone with hyphae of Trichoderma spp. Seeds inoculated with T. harzianum showed a survival of 84% and a mortality of 16%, lower than the control group, which present a mortality of 58%; however, the treatment inoculated with F. oxysporum had the highest incidence of “disease” with 83%, the lowest survival (17%) and a decrease of the green biomass with respect to the control.

Strawberry wilt is an established disease of strawberry crops caused by fungus Fusarium solani. In Mexico, strawberry cultivation represents an important productive activity for several rural areas; however, wilt disease affects producers economically. The objectives of this research were: (a) to identify and morphologically characterize strain “MA-FC120” associated with root rot and wilting of strawberry crops in Santa Cruz Analco, municipality of San Salvador el Verde, Puebla-Mexico; (b) to evaluate the potential of single and multiple applications of four broad-spectrum fungicides used against F. solani in vitro. Plant tissue samples were collected from strawberry crops in Puebla-Mexico with presence of symptoms of desiccation and root rot. Strain “MA-FC120” was identified as F. solani, being the causal agent of wilt and root rot in strawberry plants from Santa Cruz Analco. Fungicide Benomyl 50^® showed the highest percentage of inhibition on F. solani (100%) under in vitro conditions. The fungicide Mancosol 80^® and Talonil 75^® at low concentration (600 and 450 mg L⁻¹) showed no toxicity, being harmless to strain MA-FC120. However, fungicide Talonil 75^® showed slight toxicity at the dose recommended by the manufacturer and moderate toxicity in high concentration (1350 mg L⁻¹). Likewise, Captan 50^® in its three concentrations evaluated showed slight toxicity, obtaining around 50% on the classification scale established by International Organization for Biological Control (IOBC).