Some species of Agave are highly endangered due to overexploitation and highly inefficient propagation systems. Consequently, an objective of this study was the establishment of reliable in vitro protocols for Agave propagation. In order to obtain a consistent micropropagation system for A. tequilana, 2,4-D-temporary pulses (exposure of explants for 1, 3 or 6 days) with concentrations of 2.3, 4.5, 6.8 and 9.0 mM were applied to apical shoot explants. For in vitro propagation of A. salmiana subspecies crassispina, A. duranguensis, A. oscura, A. pigmaea and A. victoria-reginae, a range of IBA levels (0.049, 0.49 and 2.46 lM) in combination with BA concentrations (0.44, 2.22, 4.44, 13.31 and 26.63 lM) were tested. After 60 days of culture, 12 axillary shoots per explant were obtained when Agave tequilana tissues were treated with 6.8 mM 2,4-D for 3 days. The most axillary shoots per explant were induced on several Agave species using IBA/BA treatments as follows: 3 for A. salmiana subspecies crassispina with 0.49/ 4.44 lM, almost 6 (5.9) for A. duranguensis with 0.049/4.44 lM, ca. 13 (12.8) for A. oscura with 2.46/ 4.44 lM, approximately 6 (5.6) for A. pigmaea with 0.49/13.31 lM and ca. 6 (5.5) for Agave victoriareginae with 2.46/2.22 lM. Although axillary shoot production by different Agave species varied depending on the IBA to BA ratio, low concentrations of these growth regulators improved shoot production compared to those reported in other studies.

Amaranthus hypochondriacus is a C4 pseudocereal crop capable of producing reasonable grain yields in adverse environmental conditions that limit cereal performance. It accumulates trypsin inhibitors and alpha-amylase inhibitors in seeds and leaves that are considered to act as insect feeding deterrents. Foliar trypsin and alpha-amylase inhibitors also accumulate by treatment with exogenous jasmonic acid (JA) in controlled laboratory conditions. Three field experiments were performed in successive years to test if two nonphytotoxic dosages of JA were capable of inducing inhibitor activity in A. hypochondriacus in agronomical settings, and if this induced response reduced insect herbivory and insect abundance in foliage and seed heads. The performance of JA-treated plants was compared to insecticide-treated plants and untreated controls. The effect of exogenous JA on the foliar levels of six additional putatively defence proteins was also evaluated. Possible adverse effects of JA induction on productivity were evaluated by measuring grain yield, seed protein content, and germination efficiency. The results present a complex pattern and were not consistent from year to year. To some extent, the yearly variability observed could have been consequence of growth under drought versus nondrought conditions. In a drought year, JA-treated plants had lower levels of insect herbivory-derived damage in apical leaves and panicle than control plants, whereas in nondrought years, there was an inconsistent effect on aphids, with no effect on lepidopteran larvae. JA treatments reduced the size of the insect community in seed heads. The effect varied with year. Exogenous JA did not adversely affect productivity, and in the absence of drought stress, the higher dosage enhanced grain yield. Induction of defensive proteins by JA, although sporadic, was more effective in nondrought conditions. The patterns of foliar protein accumulation observed suggest that they may be part of a constitutive, rather than inducible, chemical defense mechanism that is developmentally regulated and critically dependent on the environment. The results emphasize the difficulties that are often encountered when evaluating the performance of chemical elicitors of induced resistance in field settings.

An out-of-plane digital holographic interferometry system is used to detect and measure insect's wing micro deformations. The in-vivo phenomenon of the flapping is registered using a high power cw laser and a high speed camera. A series of digital holograms with the deformation encoded are obtained. Full field deformation maps are presented for an eastern tiger swallowtail butterfly (Pterourus multicaudata). Results show no uniform or symmetrical deformations between wings. These deformations are in the order of hundreds of nanometers over the entire surface. Out-of-plane deformation maps are presented using the unwrapped phase maps.

Los insectos han sido un elemento importante no sólo por su función en los ecosistemas terrestres, sino también por su influencia en las sociedades humanas. Desde los albores de la humanidad estos organismos han sido parte de la alimentación, la salud, la cultura y de los agroecosistemas no sólo como competidores, sino también como elementos pronosticadores y promotores de servicios ecosistémicos. Dado el creciente interés en la restauración ecológica y en modelos de desarrollo sustentables como la agroecología, los insectos se posicionan como un excelente punto de partida para desarrollar propuestas de desarrollo acordes con las necesidades de la sociedad actual. En el presente trabajo se exploran las virtudes que hacen de los insectos un sistema importante de conocimientos, que va de lo natural y productivo, hasta lo social y cultural, que necesariamente requiere de aproximaciones transdisciplinarias capaces de abordar dicha complejidad y que pueden ser fundamentales para el desarrollo rural desde la perspectiva agroecológica.

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