Fenología y potencial ornamental de Euphorbia fulgens Karw. ex Klotzsch en México

Euphorbia fulgens Karw. ex Klotzsch is a species cultivated as an ornamental plant in Europe. Despite being a native and microendemic species in Mexico, it is not cultivated in this country. The objectives were to evaluate its ornamental potential and describe its phenology under greenhouse conditions. Fifty seeds of three wild populations were sown randomly obtaining 30 individuals. The BBCH (Biologische Bundesanstalt, Bundessortenamt und Chemische Industrie) scale was used to record the phenological stages, and the thermal time was determined as well. Its potential was defined based on aesthetic values and its adaptation for cultivation. Seven main phenological stages were recorded, with the flowering and fruiting stages overlapping during the winter-spring period. The full flowering stage took place 239 days after sowing, accumulating 3,680 ° C day -1. The aesthetic values were arched branches with attractive orange to bright red inflorescences, and easy adaptation to cultivation. The species showed a quality flowering cycle and shelf life of more than fifteen days

Variedades de Coffea arabica L. con manejo orgánico en Oaxaca

Mexico is an important producer of organic coffee, mainly harvested by producers with small shade plots who use a diversity of varieties. Considering organic cultivation standards, we evaluated fruit production, cherry-parchment industrial yield, and the sensory cup quality of 20 coffee varieties (10 tall stature and 10 compact stature) during six production cycles in Oaxaca, Mexico. The varieties with the highest average fruit production in six years were three compact stature: Colombia Brote Café (30.2 kg / plant), Oro Azteca (29.0 kg / plant), and Yellow Catuai (27 kg / plant). These varieties produce large beans suitable for a European-style preparation. The Aztec Gold varieties presented good aroma, acidity and body attributes. Tall stature varieties with greater intermediate yield were Batie, Dessie, Pluma Hidalgo 177, and Typica 947, with around 24 kg / plant. Pacamara and Blue Mountain had low fruit production. Some varieties achieved a good taste irrespectively of their stature. Abnormalities in beans and agroindustrial yields were similar for all varieties

Algunas consideraciones sobre el manejo poscosecha de la zanahoria

Carrot has a high content of carbohydrates, fiber, antioxidants, and minerals, and it can be con- sumed fresh or processed. Good postharvest management allows maintaining its chemical charac- teristics and organoleptic properties suitable for consumption. This review compiles information on the postharvest management of this species, emphasizing the main factors that affect its shelf life. High respiration and perspiration rate, mechanical damage, and inadequate management of conservation atmospheres reduce its postharvest quality.

Impacto del cambio climático en la distribución potencial de tres cultivos agrícolas en México

Agricultural systems are highly susceptible to climate change; however, little is known about the vulnerability of native or exotic species. In this work, we evaluated the impact of climate change on the potential distribution of three species of agricultural interest native to Mexico (cotton, peanut, and cocoa), through ecological niche models looking at the year 2050. According to the 22 General Circulation Models (GCMs) under two Representative Concentration Pathways (RCP), 4.5 and 8.5, we found increases in the potential distribution of the three species. The species with the greatest increase is cotton, finding conditions in the future in states such as Tabasco or throughout the Yucatan Peninsula.

A review of nano and micro-encapsulated phytochemical compounds for disease management in agriculture

Plant extracts (PEs) and essential oils (EOs) contain phytochemical compounds (PCs). Nevertheless, PCs can be degraded when applied on field. The use of nano-encapsulates (NEs) and micro-encapsulates (MEs) arise as an alternative to the application of botanical products. However, NEs and MEs with PCs in plant disease control have not been explored enough. This review discusses the use of PCs for plant disease control and the benefits obtained from formulations with NEs and MEs; furthermore, it discusses methods to produce NEs and MEs.

Características bioquímicas de variedades de maíz

El maíz es importante como grano básico, por ser la principal fuente de alimento del pueblo mexicano. En el estado de Guerrero, existe una gran diversidad de regiones agroecológicas, y los agricultores siembran bajo condiciones de riego y temporal. La siembra de maíz en las comunidades rurales se lleva a cabo principalmente en forma manual y aplican nitrógeno como fertilizante en dos etapas fenológicas del cultivo. El objetivo de la presente investigación fue conocer el contenido de proteína y el porcentaje de dos aminoácidos esenciales presentes en el maíz, al aplicar diversas dosis de nitrógeno y fósforo en tres variedades utilizadas en la región. El experimento se estableció en las localidades de Iguala y Apaxtla, con un diseño experimental de bloques completos al azar y tres repeticiones en arreglo factorial. La unidad experimental fue de cuatro surcos de 5 m de longitud y 0.81 m entre surcos. Para la fertilización, se utilizaron el nitrógeno y el fósforo como factores . Para cada tratamiento, se estimó el rendimiento de grano, el porcentaje de proteína, triptófano y lisina. Los resultados indicaron que los tratamientos exhibieron un efecto significativo en las cuatro variables evaluadas en los genotipos de maíz.

Shelf life of pitaya [ Stenocereus pruinosus Otto ex Pfeiff.) Buxb.] fruit affected by temperature and guar gum, beeswax, oleic acid, and thyme essential oil coatings

Pitaya [Stenocereus pruinosus Otto ex Pfeiff.) Buxb.] produces fruit with high commercialization potential, but its shelf life is limited to few days. The objective of this study was to apply biopolymeric coatings to extend the shelf life of pitaya fruits at 25 °C and under refrigeration at 12 °C. The following variables were handled at each temperature: fruits without any treatment (Control), fruits coated with 1,000 ppm emulsion of thyme essential oil, and fruits coated with 1% emulsion of guar gum, 7.5% beeswax, and 7.5% oleic acid, without essential oil, and with 1,000 ppm of thyme essential oil. Shelf life was 6 d at 25 °C, without the beneficial effect of coatings, but increased to 15 d with refrigeration and coatings based on guar gum, beeswax, and oleic acid, since fungal growth was delayed, and weight loss was reduced. This allowed fresh appearance without significant modification of color, firmness, pH, total soluble solids, titratable acidity, contents of soluble phenols and betalains, and antioxidant capacity.

Assessing hydrothermal treatment and antagonistic yeasts combination for mango anthracnose control

Anthracnose caused by Colletotrichum gloeosporioides is the main post-harvest disease in mango in almost all production areas in the world. Hydrothermal treatment (HT: 46.1 °C for 70 min) and antagonism of yeasts Pichia guilliermondii, Candida oleophila and Candida quercitrusa were evaluated in vitro and in vivo to determine the most appropriate post-harvest management of anthracnose in "Ataulfo" mango. The pathogen C. gloeosporioides and the yeasts were evaluated at concentrations of 105 conidia ml-1 and 108 cells ml-1, respectively. The growth areas of the pathogen subjected to HT and in interaction with the yeasts were evaluated with ImageJ software. Subsequently, the most effective strains and the HT were evaluated in "Ataulfo" mango inoculated with C. gloeosporioides and the severity of the anthracnose was determined. In the in vitro assays, P. guilliermondii strain CDBB-932 was the most effective (18.6%) in controlling pathogen growth, presenting an inhibition halo that the rest of the yeasts did not show. In the in vivo assays, the combination of HT and C. quercitrusa (strain 42) was the most effective (96.8%) in the control of anthracnose. The hydrothermal treatment in combination with yeasts could be implemented preventative control of the postharvest diseases.

Fosfitos de potasio en el manejo de Peronospora sparsa Berkeley y calidad floral del cultivo de rosa cv. Samouraï ®

Peronospora sparsa Berkeley limits the production of rose as a cut flower up to 100%. In some crops, potassium phosphites are used as a sustainable alternative for the control of oomycetes. The objectives were to evaluate the biological effectivity of commercial formulations of potassium phosphite for the management of P. sparsa, and to calculate their effect on the quality of rosa cv. Samouraï® stems and flower buds. A randomized complete block design with five treatments and an absolute control with six repetitions were used for two consecutive years. The following aspects were evaluated: incidence, disease severity, biological effectiveness, and floral quality through the length and diameter of flower stems and buds. The potassium phosphites evaluated reduced incidence to 81.7% and severity from 71.7 to 97.0%, which led to a biological effectiveness of 96.9% with FosfiMax 40-20®. The Defense Ax ® treatment increased the length and diameter of the button compared to the other treatments.

Processing effect on the bioactive compounds content of Mexican jalapeño peppers for chipotle ( Capsicum annum L.)

The objective of this work was to evaluate the antioxidant capacity and bioactive compounds content in two Jalapeño pepper varieties, both fresh and smoked-dehydrated (chipotle) and in commercial chipotle pepper sauces. The antioxidant capacity, capsaicin content, carotenoids and total phenols were evaluated. The smoked-dehydrated process had an effect on all the variables analysed (P?0.05). The chipotle pepper presented higher antioxidant activity (112.33 µmol ET/g) and content of bioactive compounds than fresh pepper and commercial sauces. In fresh pepper, the 100-Grande variety had higher antioxidant capacity (71.92 µmol ET/g) than Apache (48.31 µmol ET/g), while no effect on any of the analysed variables was reported in chipotle peppers. It is concluded that the smoked-dehydrated process of jalapeño pepper affects quality in a positive way, significantly increasing the nutritional and functional value derived from an increase in the bioactive compounds content and the antioxidant activity of chipotle peppers due to this process.