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Los trips son una plaga de importancia económica en múltiples cultivos, entre ellos mango; altas densidades de trips causan pérdidas significativas. El manejo convencional se basa en el uso de insecticidas químicos sistémicos que acarrean inconvenientes como selección de resistencia, contaminación ambiental e intoxicaciones. El objetivo del estudio fue evaluar la efectividad insecticida de productos biorracionales, como alternativas de manejo de trips. Se utilizaron arboles de mango cv. manila en un diseño experimental completamente al azar; se aplicaron cinco tratamientos insecticidas, T1: Aceite parafínico, T2: extracto de ajo + extracto de chile picante + extracto de canela, T3: Extracto de neem + extracto de canela, T4: Extracto de aceite neem todos a 2.0 L/ha, T5: Spinetoram a 500 mL/ha y T6: testigo sin aplicación. Se realizó una evaluación previa y tres posteriores a la primera aplicación, se contabilizó y evaluó la cantidad de individuos por inflorescencia o brote vegetativo, con los datos de la fluctuación poblacional se realizó un análisis de varianza y comparación de medias (Tukey, p=0.05). Se destacó la presencia de Frankliniella invasor como especie dominante. En la primera evaluación, de manera consistente en todo el experimento Spinetoram (dosis 500 mL/ha) obtuvo las mejores eficacias de control; en la segunda y tercera fecha de evaluación T2: Extracto: ajo + chile + canela (dosis 2 L/ha) registro altos niveles de control. Aquellos tratamientos que con mezcla de extractos mantuvieron altos niveles de control. Dos aplicaciones semanales consecutivas, son suficientes para mantener bajas poblaciones de trips por 21 días.

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M. O. (2020) Effects of temperature and tomato variety on development stages of Bactericera cockerelli (Sulc) (Hemiptera: Triozidae). Acta Zoológica Mexicana (nueva serie), 36, 1-10.ABSTRACT. Tomato is one of the most consumed vegetables per capita in the world; it is grown both in the open and in greenhouses. Under these conditions, the pest is considered a severe problem, especially considering Bactericera cockerelli Sulc. Therefore, in this experiment, the life history of this pest insect in two tomato varieties: "Charanda F1" and "Rafaello" the differences in the development stages of the insect, the mean temperatures of two cycles, and the accumulated heat units determined. The work consisted of evaluating the development of the instars of B. cockerelli during two crop cycles in both varieties, as well as the accumulation of heat units to differentiate the distinct instars. The insect populations developed in the Rafaello variety had shorter lives and showed a higher death rate of eggs than did those that developed in Charanda F1. The temperature was another determining factor; when the temperature remained low, the insect biological cycle was longer. Likewise, heat units were different between the two varieties; in Rafaello, 598.13 heat units needed while in Charanda F1, only 464.98. The differences may be due to the morphological characteristics of each variety, as the presence of trichomes and oils. Thus, we suggest that these variables studied in future research works.

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Objective: To evaluate the effect of two concentrates and corn stover on the productive performance and economic impact of finished hair sheep lambs. Design/methodology/approach: Twenty hair lambs (Dorper × Katahdin) with initial live weight of 33.3 ± 2.9 kg, were grouped into ten blocks where each block had two lambs of similar live weight that were randomly assigned to two treatments: T1) commercial concentrate + corn stover and T2) experimental concentrate + corn stover, in proportion 80 - 20%. Total weight gain (GPT), daily weight gain (GDP), dry matter intake (DMI), feed conversion (FC), feeding costs, gross value of GPT, gross profit margin and economic efficiency (EE). An analysis of variance was performed under a completely randomized block design. The means were compared with the Tukey test at α = 0.05. Results: There were no differences in GPT, GDP, CA and CMS (P>0.05). The T1 has higher costs (US$41.91) per ton of feed. The production costs of diets and feeding costs were lower for T2, and it also showed the best economic efficiency (EE = 26.6 %). Limitations on study/implications: The advantage of using agro-industrial and agricultural by-products such as corn stover in integral diets for finishing sheep is their availability throughout the year. Findings/conclusions: The finishing of lambs is profitable when the producer formulates and elaborates his own diet, reducing production costs for feeding without affecting the productive variables.

Ceraeochrysa claveri Navás (Neuroptera: Chrysopidae) is a predator found in several agricultural ecosystems and feeds on insects and phytophagous mites. Its high reproductive potential and forage capacity makes it a candidate for biological control of agricultural pests. Raoiella indica Hirst (Acari: Tenuipalpidae) is an important pest that can damage several species of palms, in particular, Cocos nucifera L. Given the scarcity of available knowledge about the biological aspects of Chrysopidae fed with phytophagous mites, the present work aimed to study the larval development of C. claveri fed mainly with R. indica, in order to obtain information that would be of help in the integrated management of this pest. The evaluation was performed in the F0 generation. Larva 3 is the instar that consumes the most mites (F value = 32.99; P > 0.0001) (L3: 46.80 ± 10.12 a; L2: 9.80 ± 1.23 b; L1: 9.40 ± 1.58 b). C. claveri did not complete larval development when fed only with R. indica. Larval instars L1, L2 and L3 lived 7.4 ± 2.2, 7.6 ± 1.9 and 9.0 ± 3.9 days, respectively. The larvae that reached the pupal stage failed to grow further. When adding Sitotroga cerealella Olivier (Lepidoptera: Gelechidae) eggs to the diet, the development lasted 7.9 ± 0.2, 7.4 ± 0.8, 6.5 ± 0.9 and 13.6 ± 0.9 days for L1, L2, L3 and pupae, respectively. The adults lived on average 6.7 ± 4.9 days. The sexual ratio was rt = 0.42. According to the conditions under which the experiment was carried out, it can be inferred is that C. claveri cannot complete its development by feeding only on R. indica, and that it thus consumes this mite as an occasional prey. Highlights: Ceraeochrysa claveri is a predator found in various agricultural ecosystems and feeds on insects and phytophagous mites. Raoiella indica is an important mite that can damage several species of palms, in particular Cocos nucifera Ceraeochrysa claveri does not complete its biological cycle by feeding only on indica. By adding another protein source to L3, it can reach the adult stage in 35.4±2.8 days. Ceraeochrysa claveri does not complete its cycle by feeding only on R. indica and consequently takes this mite as occasional prey.

<p><strong>Background. </strong><em>Heterorhabditis</em> and <em>Steinernema</em> are two genera of entomopathogen nematodes used as effective biocontrollers in pest insect control. <strong>Target. </strong>To describe the morphometry, morphology and thus the molecular description of a new <em>Heterorhabditis</em> indica isolate, for the cultivation of sugarcane and its possible contamination against insect pests in Mexico. <strong>Methodology</strong>. This was obtained from soil samples through the technique of the insect bait <em>(Galleria mellonella</em>). Morphometric and morphological studies, in addition to molecular techniques (ITS1+5.8S+ITS2), were performed to correctly identify <em>H.</em><em> indica</em> CP13JA strain. This new strain of <em>H. indica</em> for the state of Veracruz was compared to <em>H. indica</em> originally described in India. <strong>Results.</strong> The presence of <em>H. indica</em> isolated from the sugar cane crop is reported in the state of Veracruz, Mexico. Likewise, the results obtained in this investigation identified as the characteristics of infectious juveniles, as well as amphitic males and females do not present differences in relation to the morphometry, morphometry and morphology of the original description; as well as in the molecular studies of the SU rDNA. <strong>Implications. </strong>Therefore, the presence of <em>H. indica</em> strain CP13JA is considered important within the sugarcane crop and for the state of Veracruz where it was isolated, as well as the potential that this isolation may have for the insect pest insects belonging that attack this crop<strong>. Conclusion.</strong> <em>H. indica</em> strain CP13JA does not present morphometric and molecular differences with the species recently described in India, in addition the presence <em>of H. indica</em> is considered new within the cultivation of sugar cane in Mexico</p>