Vegetable production under greenhouse conditions in Mexico has increased notably during the last years; in this case, Bell Pepper occupies a surface of 171.4 ha with a yield of 70.8 t ha -1 . The objectives of this trial were to know the potential yield and fruit quality of Bell Pepper varieties and two INVESTIGACIÓN

Intrinsic soil fertility and the method of irrigation can affect the efficiency of nitrogen (N) fertilization, modify the yield goal, growth, and nutritional status of crops. A study was carried out with the objective of determining yield, growth, water use efficiency (WUE), agronomic efficiency of N (AEN), NO3- concentration in petiole cell extract (PCE) and chlorophyll index (SPAD) in a cotton crop by effect of N rates and two irrigation methods. The study consisted of two experiments established in soils of high fertility [˃13 g kg-1 organic matter (OM) and N-NO3- ˃ 30 mg kg], with varying N fertilization rates: a) flood irrigation (FRR, 11 and 220 kg N ha‑1), and b) drip irrigation (FRG, 11 to 440 kg N ha-1). Plant height and number of nodes were not affected by the applied treatments. SPAD values and NO3- concentrations in PCE were cubically related to crop yield. The highest yield and WUE was obtained in the experiment with drip irrigation. In the FRR experiment no response (P > 0.05) to N fertilization treatments was found. In the FRG experiment, application of 440 kg N ha‑1 reduced yield by 43% compared to the rest of the evaluated rates. AEN was statistically higher (P < 0.001) in treatments fertilized with 11 kg N ha‑1. The low yield response due to application of N in cotton was attributed to high concentrations of N-NO3- and OM that are present in the soils in which the experiments were conducted.

Para obtener altas producciones y calidad en chile jalapeño (Capsicum annuum L.) es necesario realizar una adecuada fertilización. El objetivo de esta investigación fue conocer la respuesta de la aplicación de gallinaza y estiércol de bovino en combinación con fertilizantes sobre la calidad y rendimiento del chile jalapeño. La investigación se realizó en Magdalena de Kino, Sonora, durante el ciclo primavera-verano 2009. Se trasplantó el 23 de marzo con la variedad Mitla. Los tratamientos que se evaluaron fueron: gallinaza (5 t ha-1), gallinaza (5 t ha-1) + 80N, estiércol de bovino (5 t ha-1), estiércol de bovino (5 t ha-1) + 80N, 150N-150P y un testigo sin fertilización. El primer corte se realizó 78 días después del trasplante, se cosechó del 16 de junio al 14 de octubre con un total de 6 cortes. Los resultados indicaron diferencias significativas entre tratamientos en rendimiento, peso, largo y ancho de fruto, así como en altura. La mayor producción y calidad se obtuvo con el tratamiento gallinaza + 80N, el cual presentó un rendimiento de 65,2 t ha-1 , contra 43,3, 17,2 y 16,2 t ha-1 a los tratamiento a base de fertilizante químico 150N-150P, estiércol (5 t ha-1) y al testigo, respectivamente.

A major obstacle to economic production of deciduous fruit tree under desert conditions is an insufficient period of chilling temperatures. Inadequate chilling on apricot may result in poor and uneven budbreak, reduced and delayed foliage development, sparse bloom, poor fruit set, and/or early grown cesation, with the objective of improve budbreak, applications of Hidrogen Cyanamide (H2 C N2) were made to mature apricot `Canino' trees on January 30. Two rates of H2 C N2 and a control were evalluated for that proposal. Amount of chilling accumulated was 360 chill hours according Da Motta model. Hidrogen Cyanamide advanced budbreak 7 days at the highest rate as compared to control. Cumulative percent budbreak on March 15 were 40, 64 and 72% for o, 0.75 and 1.5% respectively. In this year, bud abscission was similar for all the treatments.

Currently in Mexico there are few studies on agronomic management in olive production. The objective of this experiment was to evaluate three rejuvenation pruning intensities (25, 33, 50% and Control “traditional pruning”) in olive tree cv Manzanilla under hot and arid environment of Mexico. The experiment was carried out during four consecutive years from 2016 to 2019 at National Research Institute for Forestry, Agriculture and Livestock (INIFAP) in the Experimental Station Coast of Hermosillo, Sonora, Mexico. The experiment was carried out on 25-year-old olive orchard cultivar Manzanilla, planted at distance of 8 x 8 m (156 trees ha-1) and under surface irrigation. The variables evaluated were: vegetative parameters (wood weight, canopy diameter and plant height), olive yield and fruit characteristics (fruit weight and pulp-pit ratio). The experiment was organized as a randomized complete block design with five replications. Our results showed statistical differences (P<0.01) in all parameters evaluated with exception of fruit characteristics. During the rejuvenation process of the olive tree the treatment that obtained the higher yield was pruning with 25% intensity removing one trunk per year, which obtained an average yield in four years of 39.2 kg tree-1, while in the control treatment the yield was of 34.1 kg tree-1. Thus, it is possible to rejuvenate an olive orchard in four years without to affect olive yield.