Induced response against herbivory by chemical information transfer between plants

Abstract

iNDUCeD reSPONSe AGAiNST HerBivOrY iN PLANTS: Plants respond to herbivores and pathogens attack with increased emission of volatile organic compounds. These molecules act as indirect defences when attracting natural enemies of herbivores and thus benefit the plant. it remains controversial whether undamaged plants identify chemicals released by closely located, damaged plants and respond to them by increasing their defensive barriers against an imminent attack. Although the Talking Trees Hypothesis was published 25 years ago, only recently the most sceptical scientists have been convinced. The induced response to herbivory by interplant information transfer has been found in two plant-herbivore systems. However, the universality of the phenomenon and its ecological and evolutionary relevance remain unclear. The integration of Molecular Biology, Biochemistry, Physiology, and ecology begin to shed light on the mechanisms of the signal transfer. This integrative approach has developed new and more sensitive tools for identification of complex volatile mixtures and for understanding the process of biosynthesis, emission, transportation and reception of signals.Key Words: induced resistance, induced defense, insect-plant interaction, interplant air signalling, interplant communication, talking trees. respostas contra herbivoria induzidas pela transferência de informação entre plantas: Plantas respondem ao ataque de herbívoros e patógenos com liberação de compostos orgânicos voláteis. essas moléculas funcionam como defesas indiretas quando atraem inimigos naturais dos herbívoros e assim beneficiam a planta emissora. Uma questão controversa é se plantas vizinhas não-atacadas captam esses voláteis e respondem aumentando suas barreiras defensivas contra um ataque iminente. Apesar do seu forte apelo popular e da Talking Trees Hypothesis estar completando 25 anos, só recentemente os mais céticos estão sendo convencidos. Temse aceitado que respostas induzidas pela transferência de informação entre plantas ocorrem em pelo menos dois sistemas plantaherbívoro. No entanto, o grau de generalização do fenômeno e a dimensão da sua importância ecológica e evolutiva permanecem desconhecidos. Uma recente abordagem multidisciplinar, integrando Biologia Molecular, Bioquímica e Fisiologia à ecologia, acena com novas e mais poderosas ferramentas metodológicas para esclarecer os processos de biossíntese, emissão, transporte e recepção dos sinais pelas plantas. essa abordagem tem fornecido o suporte mecanicista adicional às evidências ecológicas da defesa induzida da planta, manifestada e mensurada mediante respostas ecofisiológicas e comportamentais dos insetos herbívoros.

Colonizing mars—An opportunity for reconsidering bioethical standards and obligations to future generations

“…Research on the possible function of ''swarm intelligence'' (as opposed to an individual's solitary capacities) in some invertebrate species is ongoing, challenging our common definitions of intelligence [37]. Even plants have been found to communicate when attacked by herbaceous insects [38] and hints of altruism are being studied [39]. Can we assume they do not sense and respond to pain in ways we cannot yet detect, much less measure?…”