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The production of fig (Ficus carica L.) in Mexico has become very important in recent years, due to the growing demand in the international market. The state of Morelos stands out as the main fig producer nationwide. The municipalities of Villa de Ayala, Tepalcingo and Axochiapan concentrate the highest productivity, however, serious affectations by some diseases such as rust caused by Cerotelium fici (Butler) Arthur have caused losses in crop yield. The objective of the work was to determine the incidence and severity of this disease, in two periods during the crop cycle. Representative samples with symptoms were taken in commercial plots of three municipalities in the state of Morelos. The incidence of the fungus and its severity were evaluated using a visual estimation scale, during February-March and August-October 2019. Six evaluations were made with weekly frequency during the cycle. The fungus was morphologically identified using taxonomic keys. The presence of C. fici uredospores was confirmed and it was determined that rust was present in both periods, with a higher incidence in the months of February and March (dry period). The municipalities of Villa de Ayala and Axochiapan, had the greatest affectations with 45 to 70 % severity. [ABSTRACT FROM AUTHOR]

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El cultivo de la papaya (Carica papaya L.), es uno de los principales frutales tropicales de mayor importancia socioeconómica, sin embargo, su rendimiento se ve afectado por plagas y enfermedades, siendo los áfidos vectores de virus los que causan el mayor daño. Se identificaron 17 especies de áfidos, de las cuales más de la mitad incluyen a especies con importancia en la transmisión de virus, correspondiendo en orden de abundancia a: Aphis spiraecola, Aphis nerii, Macrosiphum euphorbiae, Myzus persicae, y Aphis gossypii, los que tuvieron su mayor pico poblacional entre los meses de junio a agosto, coincidiendo con las mayores fluctuaciones poblacionales en los 5 primeros meses después del trasplante del cultivo. [ABSTRACT FROM AUTHOR]

Strawberry production has increased in Mexico, due to its taste, nutrition and high economic income. In Morelos, the production is affected by the strawberry dry wilt, a frequent disease in this crop that causes significant losses above 50% the production. The objective of this work was to identify the causal agent of the strawberry drier, perform pathogenicity tests from the isolate and compare against an isolated strain already identified, evaluate inoculation methods and observe the damage to the roots for this purpose they were analyzed plants with typical symptoms of the disease from a commercial plot were analyzed from June 2018. The identification of the fungus was made by cultural and morphological characteristics and compared with a strain of Fusarium oxysporum from Celaya, Guanajuato. The results show that the causal agent of the strawberry drier in Morelos is Fusarium oxysporum. The pathogenicity tests showed the damage caused by this fungus in the crop and its direct involvement in the fresh and dry weight of the roots in the plants. The comparison between means did not detect significant differences in the method of inoculation and the strains evaluated. [ABSTRACT FROM AUTHOR]

The distribution, incidence and severity damage caused by the dieback complex (Lasiodiplodia spp.) in Persian lime (Citrus latifolia) was determined in 46 orchards of six average years old, 25 trees per orchard in the municipalities of Amacuzac, Ayala, Coatlan del Rio, Cuautla, Jantetelco, Jonacatepec, Puente de Ixtla, Tepalcingo and Tlaltizapan of Zapata, Morelos State, Mexico. Incidence was evaluated according to the number of plants having symptoms of dieback. There were four levels of severity, where 0= healthy tree, 1= gum exudation, 2= cracking with exposure of internal tissue and 3= well-defined canker and branch dieback. Which were transformed to a percentage of means of a scale of three levels of severity, transforming to a percentage of infection using the Townsend and Heuberger equation. Data were analyzed trough the Kruskal Wallis test and Tukey (α=0.05) and p<0.0001 in incidence and severity. There was a high incidence of dieback on stems 78% of Persian lime trees. The incidence and severity of dieback of Persian trees on different orchards had a range of 31.8 to 100% and 30 to 100%, respectively. By the other hand, municipalities such as Amacuzac, Ayala, Coatlan del Rio and Tlaltizapan, had the lowest levels of incidence and severity of dieback. [ABSTRACT FROM AUTHOR]

El pulgón Aphis nerii Boyer de Fonscolombe (Hemiptera: Aphididae) es una plaga importante de la papaya, Carica papaya L. en México debido a su papel como vector del Virus de la Mancha Anular del Papayo (PRSV-p). El monitoreo de poblaciones de pulgones se realiza en campo con trampas pegajosas amarillas, sin embargo se desconoce el color de preferencia de A. nerii. Por lo que se evaluó bajo condiciones de laboratorio, el tiempo de arribo y la permanencia de adultos alados a la combinación de dos colores (amarillo, rojo, blanco, o verde) dispuestos de manera contínua o alterna. Aphis nerii arribó en menor tiempo a colores claros cuando éstos fueron mostrados de forma continua, excepto en la combinación rojoverde, donde arribó más rápido al rojo. El arribo a colores claros también se mantuvo cuando fueron mostrados de manera alterna, aunque sin diferencias significativas. No se observaron diferencias en cuanto tiempo de permanencia en algún color en particular, aparentemente la preferencia es por colores claros. Cuando se contrastan amarillo-blanco y rojo-blanco, A. nerii reposa por mayor tiempo en blanco. En el campo se sugiere emplear trampas de color claro para el monitoreo de A. nerii. The sweet pepper aphid or oleander aphid, Aphis nerii Boyer de Fonscolombe (Hemiptera: Aphididae), is a major pest of papaya ( Carica papaya L.) in Mexico, because is a vector of Papaya Ringspot virus-P (PRSV-p). Yellow sticky traps are used to monitor adults, but color preferences by A. nerii still unknown. Here, we evaluated the arrival, and permanence time for alate aphids to four colors (yellow, red, white, or green) arranged by pair, in continuous or alternate pattern. Aphis nerii arrived quickly to lighter colors when they were presented continuously, except in the red-green combination, arriving faster to red. Arrival time response to light color was maintained when shown alternately. No differences were found on the permanence time in any particular color, but apparently A. nerii chooses light colors. When yellow-white, and red-white colors were constrasted, A. nerii rests longer on white than yellow or red. Under field conditions light color traps are suggested for monitoring A. nerii. [ABSTRACT FROM AUTHOR]

En México no existe un programa de fitomejoramiento específico que use progenitores con fuentes marcadas con genes dominantes que confieran resistencia o tolerancia del sorgo a Melanaphis sacchari/sorghi. Resultados preliminares indicaron que M. sacchari tiene una menor preferencia (antixesosis) por los híbridos Ámbar, P15, y Milenia. La menor tasa intrínseca de incremento poblacional (rm) se obtuvo en los genotipos Ámbar y 85 P 20, y se comprobó la tolerancia en Ámbar, Cobalto, y 85 P 20, manifestada con las variables, área foliar, peso seco y el índice clorofílico. Estos resultados, deben ser considerados como un avance importante en las futuras estrategias de manejo y programas de mejoramiento vegetal que se ejecuten para el combate de M. sacchari/sorghi en sorgo. To date, there is limited information on sources of resistance to Melanaphis sacchari/sorghi , in Sorghum bicolor (L.) Moench hybrids. These cultivars are sold by different seed companies in Mexico, basing their recommendations fundamentally on the potential yield of each genotype. So, there are no specific breeding programs that use sources marked from progenitors with dominant genes that confer resistance or tolerance to the insect. The objective of this study was to evaluate resistance mechanisms such as antixenosis, antibiosis, and tolerance in six commercial sorghum hybrids against M. sacchari at Morelos. Preliminary results indicated the aphid had less preference (antixenosis) for Ambar, P15, and Milenia hybrids. The antibiosis shown through the Lower Intrinsic Rate of Population Increment (rm), occurred in genotypes Ambar and 85 P 20, and there is evidence of tolerance based on the variables leaf area (AF), dry weight (PS), and chlorophyll index (Cl), with Ambar, Cobalt, and 85 P 20. These results should be considered an important advance in future management strategies and programs for the control of M. sacchari/sorghi in sorghum. [ABSTRACT FROM AUTHOR]

Prickly pear cactus pads of Opuntia ficus-indica (L.) (Cactaceae) are cultivated in Mexico for fresh consumption. We report that Loxomorpha flavidissimalis (Grote) (Lepidoptera: Crambidae), the cactus webworm, was observed recently in farms in Morelos and has expanded its distribution south from its previously known distribution of northern to central Mexico. Female and male genitalia are fully illustrated to facilitate identification. The cactus webworm represents an additional potential pest to cultivated prickly pear cactus in central Mexico. [ABSTRACT FROM AUTHOR]

The dissipation of three field-applied pesticides (chlorothalonil, chlorpyrifos, and malathion), on cultivated prickly pear ( Opuntia ficus-indica (L.) Mill.) pads was studied. The extraction of pesticides was carried out using the European quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction technique and detection was carried out using tandem liquid chromatography with mass spectrometry. At harvest, 15 days after application, pesticide dissipation was below the level of detectability. Dissipation curves for prickly pear pads fit to a first-order kinetic equation. Two initial concentration levels were used for each pesticide. The approximate dissipation time for all pesticides studied was similar (10 days) and the half-life time was around six days. Final concentrations for the three pesticides were below the reference maximum residue level (MRL) (0.01 mg/kg), which suggests that these products can be applied safely in the commercial production of prickly pear pads at the established concentrations.