The availability of water and nitrogen in the soil affect the metabolism of onion bulbs. The synthesis of metabolites and bioactive compounds are the most affected, along with the quality of the onion bulbs However, it is necessary to know the effects of different water levels and nitrogen fertilization to optimize the quality of the onion. The objective of this research was to study the effects of the different conditions of hydric stress and nitrogen fertilization during the development of onion (Allium cepa L.) crop, regarding its physicochemical and bioactive properties. Onions were grown using four available irrigation regimes (25, 50, 75 and 100%) and four doses of nitrogen fertilization (100, 150, 200 and 250 kg N ha⁻¹). Onion without any treatment was considered as a control. The treatments low in irrigation and nitrogen fertilization increased the pH level (5.7 to 5.9) and bulb coloration in bright white/yellowish tones. An increase was observed compared to control in titratable acidity (0.13%) just in the nitrogen content, ascorbic acid (46%) and antioxidant capacity with DPPH (12.3%) and ABTS (93.7%). A decrease was shown in soluble solids (14.6%), firmness (3.5 kg cm⁻²), dry matter (6.6%), total phenols (50%) and FRAP (33.2%) values. Pyruvic acid remained constant (1.5 µmol g⁻¹ FW). The onion bulb extracts showed an erythroprotective effect with a hemolysis inhibition percentage higher than 95%. Finally, the onions had low pungency, and were soft and extra sweet. The treatments with 25% usable humidity and nitrogen fertilization of 150 and 250 kg ha⁻¹, favored the physical, chemical and bioactive quality of the onion bulb.

Salinity of soil in arid and semiarid regions is a problem that affects the production and quality of fruit. That’s while we evaluated grafting on watermelon plants as an alternative to reduce the salinity effects. The experimental design was of randomized blocks, three treatments (cultivars Sangria, Summer Flavor 800 and Summer Flavor 840) with three repetitions. The cultivars were evaluated in grafted and ungrafted condition. The rootstock used for grafting was the interspecific hybrid Strong Tosa (C. maxima x C. moschata). In average terms for the three cultivars, grafting increased commercial production, weight, length and diameter of fruits in 160.5%, 36.5%, 12.0% and 7.5%, respectively. Sangria presented the best answer in production with 57.1 t ha-1, weight 5.8 kg, length 35.0 cm and diameter 17.8 cm of fruits. Also, grafting favored in 6.3% the luminosity and reduced 6.4% Hue angle. Summer Flavor 840 showed the best result in luminosity with 48.3 and hue angle 26.4°. Firmness, °Brix and lycopene content were not modified by grafting. Grafting represents an alternative for watermelon production in saline soils, improving yield and quality of the fruits.

Grafting cucurbitaceous crops is an alternative for protection of plants in production systems with biotic or abiotic stress. The grafting cucumber improves the plant growth and development under adverse conditions, such as drought, high salt concentration and soil-borne pathogens. Lagenaria siceraria is a species with potential rootstocks in cucumber. Mexican L. siceraria accessions are less susceptible to damage caused by Meloidogyne incognita. The aim of this study was to evaluate two Mexican L. siceraria accessions (Lag 48 and Lag 53) and Forticuke F1(Numhems®) as rootstocks on plant growth and fruit quality of cucumber in soil infested with root-knot nematodes.Plant ungrafted was used as control. The results show that rootstocks increased plant height, leaves number and leaf area. Forticuke F1 and Lag 53 had a greater response than ungrafted plant. Thegrafting increased fruit weight in 25.3%, 15.2% and 14.6% with Forticuke F1, Lag 53 and Lag 48,respectively. Internal firmness of the fruits increased by 56.4% in Forticuke F1, 12.6% in Lag 53 and 2.2% in Lag 48 with respect to ungrafted plants. Length, diameter, external firmness and Brix degrees of fruit were not modified by rootstock effect. The use of L. siceraria as rootstock is an alternative to improvement plant growth and fruit quality of cucumber in soil infested with root-knot nematodes.

The use of Lagenaria siceraria rootstocks in watermelon production has favored fruit yield and quality under conditions of environmental stress. However, it is necessary to know if the differential characteristics of fruit and seed L. siceraria are related to watermelon yield and fruit in grafted plant. The objective was to evaluate two dissimilar groups of Mexican L. siceraria as rootstock in Tri-X 33 watermelon variety to relationship the morphological characteristics of rootstock with productive variables and fruit quality. The treatments were Tri-X 313 variety ungrafted and grafted with accessions of group 1 (L46 and L56) and group 2 (L48, L50 and L54). Variables evaluated were fruit and yield and quality parameters. No differences were found between groups of L. siceraria in fruit yield and external quality parameters. With the exception of pulp firmness and luminosity, LG1 surpassed group LG2 by 30.7 and 5.0%, respectively. While, when comparing grafted and ungrafted plants, it was found that grafted plants were superior, with increases of 277.8% in number of fruits per m², 330.2% in commercial production, 54.6% in rind thickness, 85.2% in external firmness and 36.3% in chroma value of fruit pulp. Meanwhile, pulp percentage and hue were reduced by 13.8% and 15.5%, respectively, in grafted watermelons. Thus, the seed and fruit characteristics are not sufficient criteria to select L. siceraria rootstocks for watermelon production.

En la actualidad la producción de cultivos depende en gran medida de la implementación de tácticas tendientes al control de una gran diversidad de problemáticas que afectan de una forma importante a la producción y la calidad de cultivos. En este estudio, se aplicaron una serie de técnicas de laboratorio con el objetivo de generar información sobre las especies que, perteneciendo a diferentes grupos taxonómicos, dentro del padrón de cultivos del Valle de Mexicali, Baja California, constituyan una opción, para ser establecidos en suelos con problemas vasculares. El experimento se estableció bajo condiciones de laboratorio en las instalaciones del Instituto de Ciencias Agrícolas, ubicado en el Ejido Nuevo León, Mexicali, B.C. Se utilizó un diseño en bloques completos al azar (DBCA) con los siguientes tratamientos: A. Tratamiento Testigo, B. Lesión + Inóculo, C. Inóculo y D. Lesión. Después de emergidas las plántulas, aproximadamente a los 10 cm, se realizaron las inoculaciones correspondientes. Se efectuó un registro de las siguientes variables de estudio: 1. Peso de raíz (g), 2. Peso de tallo (g), 3. Longitud de raíz (cm) y Longitud de tallo (cm), en siete especies agrícolas, que se producen comúnmente en la zona agrícola. La información obtenida se procesó mediante el análisis de varianza (ANVA), aplicando la prueba de comparación de media de Duncan a = 0.05. Los resultados obtenidos indican comportamientos contrastantes relacionados con la respuesta de las plántulas analizadas hacia la influencia de la cepa de Fusarium oxysporum fsp. medicaginis , el fitopatógeno utilizado en la inoculación; donde destaca que en algunas especies agrícolas se obtuvieron resultados en función de la conducta esperada para las cuatro variables medidas, por ejemplo en el cultivo de frijol, el cual demostró un grado de susceptibilidad asociado al grupo familiar al que pertenece. De igual forma, se pudieron observar marcados contrastes en el resto de las especies evaluadas, un comportamiento muy diferente conforme a lo normalmente esperado. A grandes rasgos, se puede concluir que esta metodología de laboratorio es muy importante, ya que se puede probar la susceptibilidad de las especies cultivables hacia un fitopatógeno determinado, en un tiempo relativamente rápido; recomendándose tener especial cuidado sobre el grado de desarrollo del inóculo utilizado, haciendo énfasis en el número de repeticiones implementadas.