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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]

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]

The aim of the research was to evaluate the in vitro sensitivity of Colletotrichum acutatum antracnosis to seven fungicides. It began with an isolate preserved in the ceparium of the Phytopathology Laboratory of the High School Studies of Xalostoc, Morelos. A completely randomized design was used to evaluate the fungicides benomyl, diphenoconazole, azoxystrobin, trifloxystrobin, copper oxychloride, fluoxastrobin and captan at high, medium and low doses, for a total of 22 treatments with six repetitions. Sterile distilled water was applied to the control. The treatments were applied at a rate of 5 mL per plate, which contained PDA medium and a mycelial disc (ᴓ 5 mm). The inoculated plates were incubated at 24 °C; in 12 hour photoperiod. The colony diameter was measured every 24 hours and the percent inhibition was calculated. A bifactorial variance analysis was performed, according to Fungicide and Dose; and the differences between treatments were detected by the LSD test with 95 % confidence. The diameter of the colony and the percentage of inhibition did not show differences for dose levels, without significant effects for the interaction of both factors, fungicides, and dose. However, all doses of the different fungicides inhibited colony growth compared to the control. The benomyl, difenoconazol and captan fungicides were able to totally reduce the growth of the C. acutatum colony; followed by copper oxychloride, azoxystrobin, fluoxastrobin and trifloxystrobin in decreasing order. Only benomyl, difenoconazol, captan and copper oxychloride achieved more than 50 % inhibition. [ABSTRACT FROM AUTHOR]

Some studies have reported the low genetic differentiation of Melanaphis sacchari/sorghi and its great phenotypic plasticity to quickly undergo adaptive changes that include change of host and rapid dispersion. In this experiment, damage and behavior of six commercial Sorghum bicolor (L.) Moench hybrids , against attack by the aphid were evaluated at Xalostoc, Morelos. The incidence of the sugarcane aphid from 21 after days sowing (ADS) was observed in all genotypes, despite insecticides coating the seed. The intensity of attack was light (25%) to 35 ADS. The intensity increased at the 49 ADS to (grade 2), with least severity in the Ambar hybrid (50.6%) and the greatest for Milenia (65%). The aphid was most abundant at 56 ADS, with P20 (85%) and Milena (83.7%) the most affected hybrids. At the end of the crop cycle, two groups were formed, the least infested (85 P15, Ambar, and DKS-46) and the most damaged one (Milenia, Cobalt, and 85 P20). Agronomic variables such as fresh weight of the plant, plant height, tang weight, and dry weight of the plant were not different. There were differences only in the brix degrees, with low values for Ambar (3.5°Bx) and P15 (4.2°Bx) hybrids, significantly different from 85 P20 (6.9) and Milena (6.5°Bx). Algunos estudios han informado la baja diferenciación genética de Melanaphis sacchari/sorghi y su gran plasticidad fenotípica, para someterse rápidamente a cambios adaptativos que incluyen el cambio de huésped y provocan la rápida dispersión de este insecto. En el ensayo se evaluó el nivel de daños y comportamiento de seis híbridos comerciales de Sorghum bicolor (L.) Moench, frente al ataque de este pulgón en Xalostoc, Morelos. Como resultado, se observó una incidencia del pulgón amarillo desde los 21 días de la siembra (DDS) en todos los genotipos, pese a los insecticidas presentes en la semilla. La intensidad del ataque fue ligera (25%) hasta los 35 DDS. Con un aumento de la intensidad a los 49 DDS (grado 2), con la menor severidad en el hibrido Ambar (50.6%) y el más elevado en Milenia (65%). A los 56 DDS se produjo el pico más elevado del ataque del pulgón, siendo los más afectados, 85P20 (85%) y Milena (83.7%). Al final del ciclo se formaron dos grupos, los menos infestados (P15, Ambar y DKS-46) y los más dañados (Milenia, Cobalto y 85 P20). Las variables agronómicas como: peso fresco de la planta, altura de la planta, peso de la panoja y peso seco de la planta no tuvieron diferencias. Solo hubo diferencias en los grados brix, con valores bajos para los híbridos Ambar (3.5°Bx) y 85 P15 (4.2°Bx), mismos que difieren de los que tuvieron valores más elevados, 85 P20 (6.9) y Milena (6.5°Bx), mientras éstos no se diferenciaron de DKS-46 y Cobalto con 4.7 y 5.2°Bx, respectivamente. [ABSTRACT FROM AUTHOR]

The efficacy of six fungicides for the control greasy spot (Mycosphaerella citri Whiteside) in orange (Citrus sinensis (L.) Osbeck) cv. 'Valencia' was evaluated in plots with a randomized block design and six treatments: (Azoxystrobin + Difenoconazole), Flutriafol, Difenoconazole, Benomyl, Copper Oxychloride, Trifloxyistrobin and a control. Three spraying, were made, every fifteen days. During the assay, the incidence, severity and efficacy of the diseases were evaluated. In addition, area under the disease-progress curve (AUDPC) and disease-progress curve relative in percent (AUDPCr) were calculated. The data were processed through a simple ANOVA. As results, the incidence remained unchanged up to 21 days after treatment (DAT), with low values between 1,3 and 5 %, which increased from 28 (DAT) (58-96 %). The initially severity was low (0,1-3 %) and was increased up to 32 %. The efficacy 7 (DAT) had the highest percentages with Benomyl and Trifloxyistrobin (87,5 %) and Difenoconazole (75 %). While at 14 (DAT) Difenoconazole and Azoxydifem reached 87,5 %. All fungicides reduced the area under the disease-progress curve (AUDPC) in relation to the control and in correspondence the lowest cumulative relative percentages of disease-progress curve relative in percent (AUDPCr) were obtained by Flutriafol, Benomyl and Trifloxystrobin (8.4, 8.6 and 8.7 %), although without statistical differences with another fungicide, only with the control (11.2 %). [ABSTRACT FROM AUTHOR]

The effect of the Poncho®, Cruiser® 5 FS and Tools® TS insecticides applied in sorghum seed treatment (Sorghum bicolor L. Moench) on the germination, infestation of M. sacchari/sorghi and agronomic variables was evaluated. The hybrid genotype sorghum used was Ambar 752E443K (Asgrow®). The treatments consisted in the application of Poncho® at doses 4, 5, 6 and 8 mL kg-1 of seed; Cruiser® 5 FS at a dose of 2.5, 3.5, 5 and 7 mL kg-1 of seed; Tools® TS at doses 5, 6, 7 and 9 g kg-1 of seeds and an absolute control treatment. No negative effects of the treatments were observed on the germination, with germination exceeding 96% in all treatments. Doses of insecticides not exhibit a controlling effect on the populations of M. sacchari/sorghi. The effect of the insecticide treatments was not positive in the agronomic variables plant height, fresh leaf weight, fresh stem prisoner, fresh panicle weight, fresh grain weight, chlorophyll content and Brix degrees. [ABSTRACT FROM AUTHOR]

Vanadium (V) can be absorbed by plants and regulate their growth and development, although contrasting effects have been reported among species and handling conditions. The objective of this work was to evaluate the beneficial effect of V on pepper plants (Capsicum annuum L.). The plants were grown in a hydroponic system with the application of four V concentrations (0, 5, 10, and 15 μM NH₄VO₃). Four weeks after the beginning of the treatments, growth, flowering, biomass, chlorophyll concentration, total amino acids, total soluble sugars, and nutrients were determined in leaves, stems, and roots. The application of 5 μM V increased plant growth, induced floral bud development, and accelerated flowering. The chlorophyll concentration varied according to the type of plant part analyzed. The concentrations of amino acids and sugars in leaves and roots were higher with 5 μM. With 10 and 15 μM V, the plants were smaller and showed toxicity symptoms. The K concentration in leaves decreased as the V dose increased (0 to 15 μM). However, 5 μM V increased the concentrations of N, P, K, Ca, Mg, Cu, Mn, and B, exclusively in stems. The application of 15 μM V decreased the concentrations of Mg and Mn in leaves, but increased those of P, Ca, Mg, Cu, and B in roots. We conclude that V has positive effects on pepper growth and development, as well as on the concentrations of amino acids and total sugars. V was antagonistic with K, Mg, and Mn in leaves, while in stems and roots, there was synergism with macro and micronutrients. Vanadium is a beneficial element with the potential to be used in biostimulation approaches of crops like pepper. [ABSTRACT FROM AUTHOR]

The presence of well-defined and depressed circular leaf spots, dark in their core and surrounded by a light brown dim halo, was observed on Dendrobium nobile plants in the municipality of Ixtaczoquitlán, state of Veracruz, Mexico, in 2019. Colletotrichum isolates were consistently obtained from symptomatic plants of D. nobile. The morphological characteristics of these isolates resembled each other, and their pathogenicity could be confirmed based on the necrotic lesions caused by three of these isolates on D. nobile plants 10 days after inoculation. The causal agent of this disease was identified as Colletotrichum karstii, based on morphological characteristics and the partial sequences of the ITS1-5.8S-ITS2, calmodulin and β-tubulin genes of the DNA of three representative isolates(CKFG004, CKFG005 and CKFG006). To our knowledge, this is the first report which identifies C. karstii as the causal agent of anthracnose of D. nobile leaves in Mexico. [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]

There are several postharvest fungi that cause diseases and that greatly reduce the storage life of the papaya fruit. The objective of the study was to evaluate the antifungal effect of films formulated with chitosan, and other natural products. Chitosan films combined with beeswax, oleic acid and essential oils of thyme, cinnamon and clove were first evaluated as inhibitors of the in vitro mycelial growth of Rhizopus stolonifer, Colletotrichum gloeosporioides, Alternaria alternata, Fusarium oxysporum and Penicillium digitatum. The formulations that responded best in vitro were evaluated by immersion of the papaya fruits, determined their effect on the control of anthracnose (C. gloeosporioides) compared with Sportak (prochloraz) at 3 mL L-1 as commercial control. Films based on chitosan, beeswax/oleic acid and essential oils of cinnamon and clove 1 % (Treatments 9, 3, 21 and 25), completely inhibited the mycelial growth of the five fungi. The treatments applied by immersion of papaya fruits did not present a significant effect on the incidence and severity of the anthracnose, only the treatment with Sportak and Chitosan had effect after 17 days of storage at 14 ± 2 ºC. Regarding quality, the biodegradable films did not affect the content of total soluble solids in the fruits and weight loss. [ABSTRACT FROM AUTHOR]

The Mexican rice borer, Eoreuma loftini (Dyar) (Lepidoptera: Crambidae), is one of the most important pests of sugarcane, Saccharum officinarum L., in Mexico, but the population dynamics of the adult are not known for conditions in the state of Morelos. During the 2013 season, 11,282 adult males were caught, with the largest number of adults trapped on the eastern and western sides of the state. Two population peaks were observed, the first during the dry season (February-June) and the second during the rainy season (October- December). Implementing monitoring of this stalk borer as part of an integrated pest management program is discussed. [ABSTRACT FROM AUTHOR]