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A study was conducted in the State of San Luis Potosí, Mexico, to evaluate the biological effectiveness of the insecticide Singular 350 SC (Imidacloprid) for control of sugarcane aphid (Melanaphis sacchari Zehntner) in the sorghum crop (Sorghum bicolor (L.) Moench) Variety: Nikel. A randomized complete block design was implemented, with five treatments and four repetitions; evaluating three doses of Singular 350 SC, a regional control consist in 300 mL ha-1 of Confidor 350 SC and an absolute witness, without insecticides. Two applications were made with a motorized sprayer backpack coupled with two full cone nozzles, being calibrated to apply a total volume of 391 L ha-1. The number of colonies, the yellow aphid infestation and the Abbott efficacy were evaluated at four times. The three doses of Singular 350 SC showed good efficiencies in the control of the number of live colonies and infestation of yellow aphid in sorghum, being greater than 85 % from the first and second evaluation date respectively. The treatments of Singular 350 SC at doses of 250 and 300 mL ha-1 were outstanding, with efficiency percentages higher than 85% from the first evaluation. [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]

A study was conducted in the State of San Luis Potosí, Mexico, to evaluate the biological effectiveness of the insecticide Singular 350 SC (Imidacloprid) for control of sugarcane aphid (Melanaphis sacchari Zehntner) in the sorghum crop (Sorghum bicolor (L.) Moench) Variety: Nikel. A randomized complete block design was implemented, with five treatments and four repetitions; evaluating three doses of Singular 350 SC, a regional control consist in 300 mL ha-1 of Confidor 350 SC and an absolute witness, without insecticides. Two applications were made with a motorized sprayer backpack coupled with two full cone nozzles, being calibrated to apply a total volume of 391 L ha-1. The number of colonies, the yellow aphid infestation and the Abbott efficacy were evaluated at four times. The three doses of Singular 350 SC showed good efficiencies in the control of the number of live colonies and infestation of yellow aphid in sorghum, being greater than 85 % from the first and second evaluation date respectively. The treatments of Singular 350 SC at doses of 250 and 300 mL ha-1 were outstanding, with efficiency percentages higher than 85% from the first evaluation. [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 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]