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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]

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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]

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]