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Brassinosteroids are steroidal phytohormones that have been widely used in agriculture, few studies on the effect they can have in inducing root formation in blueberry (Vaccinium corymbosum) cuttings have been conducted. The objective of this research was to evaluate the effect of 24-epibrasinolide (24-EBL) at different concentrations (0, 20, 40 and 60 μg L -1) and of the substrate on the rooting of cuttings, a mixture of river sand and tezontle (ST), peat (Peat Moss®) and perlite (PMP), a mixture of coconut fiber and perlite (CFP), peat (Peat Moss®) (PM) and coconut fiber (CF). The variables evaluated 30 days after the establishment of the experiment were percentage of survival (%SC), percentage of rooted cuttings (%RC), number of roots per cutting (NR), main root length (MRL) and total length of the root system (TLR). The data obtained were subjected to analysis of variance and comparison of means with the Tukey test. The results showed that blueberry cuttings with 24-EBL at a concentration of 60 μg L -1 in ST substrate have 84.7% of survival and 67.76% of rooted cuttings. Cuttings exposed to 24-EBL at a concentration of 40 and 60 μg L -1 inserted in substrate of ST mixture had a longer root length and more roots per cutting compared to other substrates. It is concluded that 24-EBL induces root formation in cuttings of blueberry plants in ST substrate. [ABSTRACT FROM AUTHOR]

Pachycrepoideus vindemiae (Rondani) (Hymenoptera Pteromalidae), a pupal ectoparasitoid, is considered a potential candidate for the biological control of Drosophila suzukii (Matsumura). To get a cost-effectively mass rearing under lab conditions, in this study, several life parameters of this parasitoid were assessed using D. suzukii pupae as host. In addition, the influence of D. suzukii pupal age on parasitism and sex ratio of P. vindemiae offspring was evaluated. Females started laying eggs when they were 0.12-d-old (= 3-h-old) and the number of eggs increased significantly when they were 0.5-d-old (= 12-h-old), with a pre-oviposition period less than 4 d after adult emergence. The maximum oviposition activity and parasitoid emergence were observed when females were very young (between 3-11-d-old for fecundity and 3-d-old for parasitoid emergence). The P. vindemiae survival rate and longevity were significantly higher in females than in males. Pupae of 48-h- and 96-h-old were significantly more parasitized than those of 24-h- and 72-h-old. The sex ratio of P. vindemiae adults was not affected by host age. We discuss the importance of the different life traits of P. vindemiae studied, especially its successful development in pupae of different ages of D. suzukii, to design a biological control strategy against this pest. [ABSTRACT FROM AUTHOR]

En agosto de 2018 en recorridos de campo realizados en lotes comerciales de fresa en la localidad de La Sauceda, Zamora, Michoacán se observaron hojas con daños por alimentación y enrollamientos, así como la presencia de larvas. Se recolectaron larvas, que se mantuvieron en condiciones de laboratorio y los adultos emergidos se identificaron como Argyrotaenia montezumae (Lepidoptera: Tortricidae). Este es el primer reporte de esta especie en México en el cultivo de fresa. [ABSTRACT FROM AUTHOR]

BACKGROUND Control of the Asian citrus psyllid Diaphorina citri Kuwayama, the most important pest of citrus worldwide, is based on the use of insecticides, though unsatisfactory results have recently been reported. In this study, insecticide resistance of D. citri to three insecticides (bifenthrin, malathion, and chlorpyrifos) was examined. RESULTS Three populations (designated Dci-CParácuaro, Dci-El Junco, and Dci-Antúnez) of both adults and fourth-instar D. citri individuals were collected in 2014 at two different times and on one occasion, respectively, from three locations (Crucero de Parácuaro, El Junco, and Antúnez). These locations represent the major commercial Mexican lemon production areas in the Apatzingán Valley in the state of Michoacán, Mexico. The three populations of D. citri adults and fourth-instar nymphs at the different collection times showed low levels of resistance (≤7-fold) to bifenthrin, but were very resistant to malathion (≤345- and ≤432-fold for adults and fourth instars, respectively) and chlorpyrifos (≤2435- and ≤1424-fold for adults and fourth instars, respectively). CONCLUSION Resistance levels to the tested insecticides were highly variable but homogeneous among seasons and localities. Resistance management programmes that include crop sanitation, use of biological and cultural control practices, and rotation of insecticide classes should be established, particularly in areas where D. citri has developed resistance to malathion and chlorpyrifos. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

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The leafrollers Argyrotaenia montezumae Walsingham and Amorbia sp. are tortricids associated with blackberry plants, in Michoacan, Mexico. In this study we analyzed and compared the abundance and diversity of parasitoids associated with these leafroller species in two commercial plantings in Los Reyes, Michoacan. A total of 1682 young leaves infested with leafroller larvae were collected, of these 994 specimens of four parasitoid species were obtained. The parasitoids were Chelonus sp. (41.6%), Apanteles n. sp. (34.2%), Colpoclypeus michoacanensis Sánchez & Figueroa (23.1%), and Bracon sp. (1%). Apanteles n. sp. recorded the highest percent of parasitism (26.9%) and it was also the species that appeared more frequently. [ABSTRACT FROM AUTHOR]