Garcinia intermedia (Pittier) Hammel, también conocida como limoncillo o toronjil, pertenece a la familia de las Clusiaceae, y se distribuye en las regiones tropicales cálidas de México y Centroamérica a altitudes de 300 a 1,000 m. Es un árbol frutal subutilizado que alcanza hasta 20 m de altura y produce frutos amarillos con hasta cuatro semillas. La pulpa es agridulce y es muy apreciada por la población rural de las regiones donde crece, en donde los murciélagos y el mono araña también la consumen. La fruta tiene propiedades medicinales; es rica en benzofenonas, las cuales atacan a las células cancerosas del colon. El fruto de G. intermedia tiene mayor capacidad antioxidante que el fruto del mangostán (G. mangostana Linn.); sin embargo, poco se sabe sobre el manejo hortícola de esta especie, y no se han reportado conocimientos básicos, como la propagación asexual o su conservación en poscosecha. No hay información sobre la conservación ex situ de esta especie en México y Centroamérica, y no se ha realizado alguna selección de ejemplares destacados con frutos de alta calidad. La mayor parte de la información reportada hasta el momento para esta especie es sobre su ecología y propiedades medicinales.

Developing new varieties of anthurium (Anthurium andreanum L.) by hybridization can take 8-10 years; therefore, induced mutagenesis can be an alternative strategy to hybridization. The objective of this work was to induce mutations in anthurium by exposing explants obtained from vitroplants to colchicine. Explants of leaves, nodes and roots obtained from vitroplants were exposed to 0.1 % colchicine for 0, 2, 3 and 4 h. The mean lethal dose (LD₅₀), survival, number of explants that generated callus, number of explants that formed shoots and the number of shoots per explant were evaluated. The karyotype of the presumed mutated regenerated plants was determined by the root apex squash technique. The leaves showed the highest sensitivity to cochicine. The survival of the root explants treated with colchicine was 100 %; 4 % of roots exposed for 2 and 3 h formed adventitious shoots (120 shoots). For nodes, the LD₅₀ was found at 3.98 h; 76 and 56 % of the nodes cultivated for 2 and 3 h with colchicine formed adventitious shoots (4.4 and 3.6 shoots). The plants regenerated from the explants exposed to colchicine showed morphological changes. The chromosomal number of the regenerated vitroplants from the explants exposed for 2 and 3 h to colchicine was 2n = 29, while that of those obtained from the explants that remained on the colchicine for 4 h was 2n = 31. The sensitivity to colchicine was a function of the type of explant and the dose used. Colchicine caused the loss (monosomy) or gain of chromosomes (trisomy).

The objective was to propagate select Physalis ixocarpa plants in vitro, acclimatize them and describe their phenological cycle. The in vitro response of stem apices was evaluated in families from the Tecozautla 04, Manzano Tepetlixpa and Morado San Miguel varieties. The apices were cultured in a medium containing Murashige and Skoog inorganic salts (100 %), supplemented with 0.4 mg·L^-1 thiamine, 60 mg·L^-1 L-cysteine, 100 mg·L^-1 myo-inositol, 0.5 mg·L^-1 nicotinic acid, 0.5 mg·L^-1 pantothenic acid, 3 % sucrose and 7 g·L^-1 agar, without growth regulators and the pH adjusted to 5.7 ± 0.1. In vitro rooting was done for 30 days, with 16 h of light at 3,000 µmol∙m^-2∙s^-1. The variables evaluated in vitro were seedling height, vigor, callus presence, root length, and number of leaves, roots, stems and buds. Plants produced in vitro were acclimatized and transplanted in greenhouses to follow their phenological cycle. The variables evaluated in acclimatization and phenological cycle were plant height and number of leaves, buds, flowers and set fruits. A completely randomized design was used for the in vitro evaluation, and randomized complete blocks for the greenhouse. The families with the best morphogenic responses in vitro were Tecozautla 04 and Manzano, and in phenological development they presented greater plant height. In acclimatization, survival was 100 % in all clones. In vitro responses, acclimatization and phenology depended on the variety and families.

I n order to evaluate the physiological quality of tomatillo seeds over time and the effect of two environments, seeds of four varieties produced in 2013 were stored for three years under ambient conditions (23.43 ± 0.64 °C and 23 % RH) and at the Germplasm Bank (-20 °C and 13 % RH) of the Universidad Autónoma Chapingo, Mexico. They were sampled every year from October 2013 to November 2016. Germination and vigor tests were performed in each sampling under a completely randomized experimental design with six replications. Germination percentage was determined at 30 °C for 21 days in a germination chamber. Vigor was evaluated by means of the germination speed index (GSI), seedling length (SL), seedling dry weight (SDW) and percentage of normal seedlings (NS). After three years of storage, germination decreased 4.3 %, where the highest percentages were obtained with the Diamante and Tecozautla 04 varieties. However, the four varieties evaluated showed more than 90 % germination. No significant effect of storage environments on germination was observed, although the highest GSI and NS values were obtained under the storage conditions of the Germplasm Bank. The Diamante variety showed the highest germination percentage and GSI values. In the vigor variables (GSI, SL and SDW) a negative influence was observed due to the effect of storage time

I ntensive tomato (Solanum lycopersicum L.) production in coastal areas of Sinaloa is exposed to significant amounts of Cl and Na deposited by sea breezes and irrigation water, which affects the yield of this vegetable. The aim of this study was to evaluate three percentage ratios of Cl^- /anions (25/100, 50/100 and 75/100) and three percentage ratios of Na⁺ /cations (25/100, 50/100 and 75/100) in the nutrient solution on mineral composition, dry matter production and yield of tomato. The experimental design was completely randomized with a 32 factorial arrangement and four replications. Analysis of variance and mean comparisons were performed (Tukey, P ≤ 0.05). Cl and Na concentrations in tomato leaves, stems and fruits increased significantly with increasing ratios of Cl^- /anions and Na⁺ /cations in the nutrient solution. The 75/100 Cl^- /anions ratio reduced (P ≤ 0.05) the Ca concentration in leaves, while the 75/100 Na⁺ /cations ratio decreased (P ≤ 0.05) K concentrations in leaves and stems. Both ratios reduced aerial dry biomass (48 and 25.8 %, respectively) and tomato yield (50.8 and 45.7 %, respectively). The results indicate that tomato plants grown with the 75/100 percentage ratio of Cl^- /anions or the 75/100 percentage ratio of Na⁺ / cations absorb excessive amounts of Cl or Na, which causes ionic imbalance (especially of K⁺ and Ca²⁺) and affects dry matter production and yield.