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The safflower Carthamus tinctorius L. it is a crop that has been adopted by a large number of producers, particularly in the Northwest of the country, due to its great adaptability and its little water requirement, due to the great demands presented by the oilseed industry in the country. Since the 1970s it has been worked to generate materials that are highly productive, with good percentage and qualityof oil and with characteristics of resistance to the main diseases present in the region (false mildew and leaf rust). For this reason, the objective of this work was to evaluate the behavior of the elite safflower lines generated by the genetic improvement program in the region (23 oleic and 1 linoleic). These lines were established during cycles 2017-2018 and 2018-2019. Its agronomic behavior was evaluated under the present conditions of the Yaqui Valley. Oleic lines were found that surpassed witnesses Ciano ol and Chey ol, varieties that are widely sown in the region. In addition, it was found that the linoleic type line had better agronomic characteristics, production and oil content than witness RC-1002 which leads to the conclusion that within the evaluated lines there are potential materials to be released as a variety. [ABSTRACT FROM AUTHOR]

Ten tomato varieties were examined for resistance to Tetranychus urticae by bioassays on leaf discs. A colony of T. urticae from different ornamental crops of Saltillo, Coahuila, Mexico, was established in bean seedlings (Phaseolus vulgaris L.) in a Biotronette chamber. At 25 ±2 °C, 60- 70 HR and 12:12 h L: D. According to the design of the experiment, the females were placed in leaf discs of the 10 tomato varieties under study in a proportion of 10 disc with 90 repetitions, the behavior was evaluated based on survival, repellency and mortality. Subsequently, 100 freshly mated and fertilized one-day-old females were transferred to discs of tomato leaves (Solanum lycopersicum L.) of 1.3 cm in diameter of cultivars ‛Tsan-101', ‛Toro', ‛Saladette' and ‛Cereza' in such a way that each experimental unit included 1 female per disk. The demographic parameters in this experiment showed a lower growth potential of this pest in the cultivars ‛Tsan-101' and ‛Toro' than in ‛Saladette' and ‛Cereza'. [ABSTRACT FROM AUTHOR]

The effect of the insecticide endosulfan on the predatory efficiency of the green lacewing, Chrysoperla carnea Stephens (Neuroptera: Chrysopidae) on the eggs of tobacco budworm, Heliothis virescens (Fabricius) (Lepidoptera: Noctuidae) and fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae) was measured with Holling’s disc equation. Though the type II functional response was maintained in C. carnea exposed to endosulfan, the functional response parameters: attack rate (a′), handling time (Th), total handling time (Tht), searching time (Ts), and search efficiency (E) were affected for both prey offered. The predator took more time to identify, pursue, capture, consume, and digest the prey, and in general, the efficiency of the predator as a biological control agent was adversely affected. [ABSTRACT FROM PUBLISHER]

The objective of this research was to compare the toxicity of reduced doses and enzymatic activity associated with insecticide tolerance to abamectin and profenofos on Chrysoperla carnea Stephens and its prey Bactericera cockerelli Sulc. Residual toxicity was measured at 0.1, 0.5, and 1.0% of the recommended dose of abamectin and profenofos for controlling B. cockerelli. Measured were α-esterases, β-esterases, glutathione S-transferases (GSTs), and oxidase content of larvae and nymphs of C. carnea and B. cockerelli exposed to the insecticides. The three abamectin concentrations killed more nymphs of the pest than did larvae of green lacewing. Profenofos at 1.0% concentration was very toxic to the pest and its predator. At concentrations of 0.5 and 1.0, fewer died and was similar for both species. Abamectin killed fewer C. carnea than did profenofos at the three doses. Enzymatic activity of α and β-esterase was greater for C. carnea compared with B. cockerelli exposed to abamectin and profenofos. Activity of the enzyme glutathione S-transferases (GSTs) and oxidase content where greater for B. cockerelli than C. carnea. The study demonstrated that abamectin was less toxic to C. carnea and more to B. cockerelli, suggesting the insecticide was very selective, which could be related to greater esterase enzymatic activity. [ABSTRACT FROM AUTHOR]

Tomato (Solanum lycopersicum L.) plants have developed or adapted over time efficient defense mechanisms against insect attack. Because the mechanisms often fail to be effective enough, alternatives are needed to help counteract attacks by pests. Sodium menadione bisulfite (MBS), a compound derived from vitamin K3, possesses insecticidal properties. In this work, bioassays were done to verify insecticidal effect of MBS on Bactericera cockerelli (Sulc) and Bemisia tabaci (Gennadius). MBS killed more than 80 and 60% of the insects evaluated, with LC50 of 54.79 and 521.72 ppm, respectively. MBS also deformed B. cockerelli adults hatched from nymphs exposed to concentrations of MBS tested under in vitro conditions. Therefore, menadione can be considered an alternative for integrated management of B. cockerelli and B. tabaci. [ABSTRACT FROM AUTHOR]

Thirty eight isolates of Phytophthora cinnamomi from five counties in Michoacan, Mexico, were genetically analyzed using amplified fragment length polymorphisms (AFLP) to determine the genetic variability and the existing relationships among the avocado isolates. The amplifications showed 296 bands. A genetic dissimilarity matrix was obtained in this trial by means of the multiple coupling coefficient and the hierarchical grouping method, also called non-weighted average method. The resulting dendogram showed two levels of association. The isolates were classified within two main groups associated with the geographical location from which they were obtained. The analysis and determination of the confidence levels demonstrated that these geographical groups are strong. [ABSTRACT FROM AUTHOR]