Objectives: To generate information about a new host of the Polyphagotarsonemuslatus (Banks) mite, and to understand the damages caused by the cultivation ofApatlexco chili pepper (Capsicum annuum L.) in the northern region of the state ofGuerrero.Design/Methodology/Approach: The identification of the mite was carried out throughtaxonomic keys and the damages caused in vegetative shoots, mature leaves andflower buds were described.Results: The P. latus mite was identified as causing important damage to the crops ofAplaxtleco chili pepper grown in greenhouses in the state of Guerrero, Mexico, and thisis the first report of this mite in the Aplaxtleco chili pepper crop grown in greenhouses inthe state of Guerrero, Mexico.Findings/Conclusions: Economic income is obtained from the cultivation of Aplaxtlecochili peppers, a characteristic crop of the municipality of Aplaxtla, in the northern zone of Guerrero; therefore, knowing the identity of the P. latus mite in the Aplaxtleco chili cropwill help to suggest effective control methods to obtain higher yields.

<p><strong>Background.</strong> The sweet biznaga (<em>Echinocactus platyacanthus</em>) is endemic to Mexico, whose seeds show low germination, viability, longevity, genetics, and latency; therefore, gamma irradiation is an alternative to stimulate the emergence and growth of seedlings, by causing variations in the chemical composition of DNA, which causes cytological, biochemical, physiological and morphological changes in plants. <strong>Objective.</strong> The objective of the present investigation was to evaluate the effect of different doses of gamma ⁶⁰Co radiation on seed germination and seedling vigor of <em>E. platyacanthus</em>. <strong>Methodology.</strong> <em>E. platyacanthus</em> seeds were irradiated at 0, 50, 100, 150, 200, 250, 300, 350, 400, 450, 500 and 550 Gy of ⁶⁰Co gamma rays, then they were sown in transparent plastic containers covered with filter paper and were distributed in a completely randomized design with four repetitions in a germination chamber, the percentage of germination and survival of seedlings in the container was recorded 30 days after sowing (das). The seedlings were transplanted at 30 das into black polyethylene bags with tezontle and established in a completely randomized design with 12 treatments and four replications, in a tunnel-type greenhouse. At 20 and 30 days after transplantation (dat) seedling vigor was measured based on height (cm), stem diameter (mm) and root length (mm) and at 20 dat survival was recorded (%) of seedling in the substrate. An analysis of variance and Tukey's test for comparison of means (p ≤ 0.05) were performed. <strong>Results.</strong> Gamma irradiation stimulated seed germination from 10 to 29%. In seedlings, root height and length were modified with intermediate doses of gamma rays (100 to 200 Gy); but higher doses negatively affected these indicators. Survival of containerized M₁ seedlings was up to 63% higher than the control, depending on the irradiation dose. <strong>Implications.</strong> Irradiation with ⁶⁰Co gamma rays improves seed germination, survival and vigor of <em>E. platyacanthus</em> seedlings. <strong>Conclusions.</strong> Irradiation with ⁶⁰Co gamma rays stimulated seed germination and improved some characteristics of vigor in <em>E. platyacanthus</em> seedlings, by modifying root height and length according to age. In addition, it increased the survival of containerized seedlings.</p>

Objetive: The objective of this study was to evaluate the yield, intercepted radiation and morphology of crotalaria (Crotalaria juncea L.) at different planting densities, in the dry tropics of the state of Guerrero, Mexico. Desing / Methodology / Approach: The treatments were: four planting densities at 400,000, 200,000, 100,000 plants ha-1 and a stream. A growth analysis was also evaluated at 30, 38, 45, 52, 60, 68 and 75 days of growth, understanding that the pod was fully developed. The variables evaluated were: dry matter yield, intercepted radiation and morphological composition. Results: The dry matter yield, regardless of the cutting age, was obtained in descending order at the planting densities of: 400,000 ˃ chorrillo ˃ 200,000 ˃ 100,000 plants ha-1 with 19,837, 17,918, 8,786 and 4,074 kg DM ha-1, Study Limitations / Implications: In the tropics it is necessary to broaden the panorama with the producers, in the use of forage legumes to improve the feeding of cattle. Findings / Conclusions: It is recommended to sow at a sowing density of 400,000 plants ha-1 and to cut after 45 days of growth in crotalaria since it is when the best structural characteristics of the meadow and 95% of intercepted radiation are found

La uchuva (Physalis peruviana L.) es un cultivo adaptable a climas adversos y prolongada producción de frutos con alto potencial económico. En México, la uchuva aún no se cultiva con fines comerciales, por desconocimiento de su consumo y rentabilidad. El objetivo fue analizar la rentabilidad del cultivo de la uchuva en invernadero e hidroponía y su consumo en la ciudad de México, para conocer su potencial comercial. Plantas de uchuva se cultivaron en un invernadero con medidas de 10 x 30 m, los insumos y actividades del proceso productivo y cosecha fueron registrados en una hoja de cálculo de Excel (2010), cuantificados y extrapolados a 1 ha. Se determinaron los costos de producción y la rentabilidad del cultivo con base en la tasa interna de retorno (TIR), el valor actual neto (VAN) y la relación beneficio/costo (B/C). El punto de equilibrio en ventas se estimó con los costos totales y la inversión inicial. La demanda se estimó con base en la información de 150 encuestas realizadas en los mercados nombrados. El 100 y Medellín, en la Ciudad de México. Se realizaron pruebas de degustación a los encuestados, considerando el sabor, olor y color de frutos comercialmente maduros. El rendimiento estimado fue de 52.65 Mg ha-1 de fruto fresco con cáliz, con una inversión de $3 664 551.00 a precio de venta de 30.00 $ kg-1, con VAN de $633 071.00, TIR de 17.24%, y relación B/C de 1.1. La demanda estuvo determinada por el precio del fruto, el ingreso y el nivel de estudios de los encuestados. La mayoría de los encuestados mostró disposición de compra de este fruto y recomendó su consumo.

Objective: Evaluate the effect of three types of substrate and different shoot lengths onthe rooting of Carica papaya L. shoots.Design/ methodology/ approach: This experiment followed a completely randomizeddesign with a 2×3 factorial arrangement. Shoots of 30 and 40 cm of length werecollected in March 2018 from the lateral branches of papaya plants (Carica papaya L.)native to various regions of Guerrero. Shoots were placed in different substrates: 1)sand, 2) Peat Moss®, and 3) sand and Peat Moss® mixture (70:30, v/v). Sixty days afterplanting, rooting percentage, root length, plant height, stem diameter, number of leaves,crown diameter, biomass fresh weight, biomass dry weight, root fresh weight, and rootdry weight were evaluated. Data were analyzed through an analysis of variance and amean difference test (Tukey, p?0.05).Results: The rooting of 40- and 30-cm shoots was 60 and 50%, respectively. Plantswith the highest height, number of leaves, root length, and crown diameter derived from 240-cm shoots. Sand was the best substrate for rooting, where plants with higher freshbiomass were significantly developed.Study limitations/ implications: Continue study during the flowering and fruitingstages.Findings/ conclusions: This protocol allows the rooting of papaya shoots.