The chemical factors that regulate the synthesis of resveratrol (RV) in filamentous fungi are still unknown. This work reports on the RV production by Arcopilus aureus MaC7A under controlled conditions and the effect of amino acid precursors (PHE and TYR), monoterpenes (limonone, camphor, citral, thymol, menthol), and mixtures of hydrolytic enzymes (Glucanex) as elicitors for boosting fungal RV. Batch cultures with variable concentrations of PHE and TYR (50–500 mg L−1) stimulated RV production from 127.9 ± 4.6 to 221.8 ± 5.2 mg L−1 in basic cultures developed in PDB (pH 7) added with 10 g L−1 peptone at 30 °C. Maximum levels of RV and biomass were maintained during days 6–8 under these conditions, whereas a dramatic RV decrease was observed from days 10–12 without any loss of biomass. Among the tested volatiles, citral (50 mg L−1) enhanced RV production until 187.8 ± 2.2 mg L−1 in basic cultures, but better results were obtained with Glucanex (100 mg L−1; 198.3 ± 7.6 mg L−1 RV). Optimized batch cultures containing TYR (200 mg L−1), citral (50 mg L−1), thymol (50 mg L−1), and Glucanex (100 mg L−1) produced up to 237.6 ± 4.7 mg L−1 of RV. Our results suggest that low concentrations of volatiles and mixtures of isoenzymes with β-1, 3 glucanase activity increase the biosynthesis of fungal RV produced by A. aureus MaC7A in batch cultures.

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.

Beans are the most cultivated legume in the world. In Mexico, it is the second most important crop after corn (FAO 2020; SIAP 2020). Bean plants “Flor de Mayo M38” variety were affected by a foliar disease during the agricultural cycle 2019 in Puebla-Mexico (19°02'46.6" LN and 98°05'15.6" LO). Necrotic V- shaped lesions were observed on the margins of the leaves surrounded by yellow halos followed by foliar necrosis, affecting 40% of the crop. In Mexico this variety of cultivars is in great demand for local consumption and generates income in foreign currency (Castellanos et al. 1997). Sampling was carried out on 50 plants “Flor de Mayo M38” variety, with necrotic leaf symptoms from ten plots of one hectare. Samples were cut into pieces (5 mm), disinfested with 1% hypochlorite 3 min, and washed with sterile distilled water. Subsequently, samples were dried on sterile paper and placed on Petri plates containing yeast extract calcium carbonate dextrose agar (YDC) medium and kept at 36°C for 3 days. Colonies of ten typical bacteria isolated from all symptomatic plants were Gram (-), small and uniform in size with rounded edges, yellow, convex with entire borders and mucoid appearance on YDC. Bacteria did not grow on 0.1% triphenyl tetrazolium chloride amended casamino acid, peptone, and glucose medium (CPG). Biochemical tests showed that isolates did not reduce nitrate to nitrites, had positive catalase and starch hydrolysis, while the Kovac oxidase test was negative (Schaad and White 1974). Genus identity of the representative isolate Xcf1-APJR, was confirmed by 16S rRNA encoding gene partial sequencing, using universal primers 518F (5'-CCAGCAGCCGCGGTAATACG-3') and 800R (5′-TACCAGGGTATCTAATCC-3′) (Halim et al. 2020). BLASTn alignments against the nucleotide collection were 100% identical to Xanthomonas sequences including Xanthomonas campestris pv. campestris strains NZ_AP019684.1, CP025750.1, and MN108237.1. The 1,418 bp sequence was deposited in the GenBank database under accession number MT645246. The identification of species/pathovar was accomplished by serological methods using a polyclonal antiserum specific for X. campestris pv. campestris (Popovic ́ et al. 2013) with the DAS-ELISA commercial kit (catalog number 07122C/096, LOEWE Biochemica GmbH, Germany). The pathogenicity test was carried out on 50 healthy bean plants from the "Flor de Mayo M38" variety. Bacterial culture incubated at 28°C for 48 h in YDC medium was used to prepare the bacterial suspension (108 CFU mL-1). The first two lower leaves of 30-day-old plants were inoculated by sprinkling. Ten plants sprayed with sterile distilled water were used as negative control. All plants were kept for 20 days in greenhouse at 18-26°C and relative humidity of 60%. After seven days, chlorotic lesions developed on all inoculated plants that became necrotic from 14 days after inoculation (dai). Necrotic leaf spots merged at 14 dai to form necrotic areas of more than 20 mm in diameter, reaching total necrosis of the leaf tissue at 20 dai and were similar to the symptoms observed in the field. Koch's postulates were confirmed by the reisolation of Xcf1-APJR strain, which presented the same colony morphology, partial sequence, and polyclonal specific detection. This is the first report of this pathogen causing necrotic leaf spot in beans from the "Flor de Mayo M38" variety in Puebla-Mexico. The author(s) declare no conflict of interest. References: FAO. 2020. FAOSTAT. Food and Agriculture Data. http://www.fao.org/faostat/en/#home/. SIAP. 2020. Atlas Agroalimentario. https://www.gob.mx/siap/. Castellanos, J. Z., et al. 1997. Arch. Latinoam. Nutr. 47:163. Schaad, N. W., and White, W. C. 1974. Phytopathology. 64:876. https://doi.org/10.1094/Phyto-64-876 Halim, R. A., et al. 2020. HAYATI J. Biosciences. 27:215. https://doi.org/10.4308/hjb.27.3.215 Popovic ́, T., et al. 2013. Plant Dis. 97:418. https://doi.org/10.1094/PDIS-05-12-0506-PDN

The infection caused by Ustilago maydis, commonly called huitlacoche, appears in regions of Mexico that produce corn (Zea mays) during seasonal conditions. The infection leads to form galls with high levels of proteins, amino acids, and minerals, providing important benefits to nutrition, and it is also becoming relevant due to its high commercial value, becoming a potential crop for Mexico, Central America, and the United States. The objectives of the present investigation are to evaluate the potential yield per hectare (Kg ha−1) based on the incidence percentage (PI), and severity index (ISE) in eight genotypes of corn, as well as performing proximal chemical analysis and mineral element analysis with the galls obtained via inoculation of the MA-Um1 strain of U. maydis. The experimental unit is made up of eight subgroups of 250 plants here, considering four hybrid and four Creole genotypes of corn used by producers in open fields in Nopalucan, Puebla, Mexico. The Creole creamy-white corn achieved the highest production of huitlacoche (12,759.21 Kg ha−1) here, obtaining an incidence percentage of 73.90%; the highest caloric content (39.90 Kcal per 100 g of fresh mushroom) was recorded in the galls produced from the Asgrow Hawk hybrid, while the highest concentration of zinc (2.33 mg per 100 g) was presented by the AS-722 hybrid.

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.