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RESUMO: Com o intuito de avaliar os efeitos da antibioticoterapia no crescimento de plantas micropropagadas de abacaxizeiros, bem como na comunidade bacteriana endofítica da espécie, realizaram-se análises moleculares. Verificou-se a presença de endófitos no interior das microplantas, mesmo após 30 dias de cultivo em meio de cultura MS, suplementado com diferentes antibióticos, e analisou-se o crescimento da parte aérea e radicular das microplantas. Decorrido o período de 30 dias de cultivo, constatou-se ainda a presença de bactérias endofíticas, no entanto, as microplantas apresentaram acentuada redução no crescimento da parte aérea e radicular, evidenciando assim a influência da microbiota endofítica no crescimento das microplantas in vitro e a importância da manutenção do equilíbrio endofítos/microplanta. ABSTRACT: This research aimed to evaluate the antibiotic therapy effects in the growing of micropropagated pineapple plants as well as in the community of the endophytic bacterial of the species. It was performed molecular analyzes and verified the presence of endophytes within microplants even after 30 days of culture on MS medium supplemented with different antibiotics and analyzed the development growth of shoots and roots of microplants. After the period of 30 days of cultivation, even being checked the presence of endophytic bacteria, it was verified that the microplants showed reduction of the growing of shoots and roots, thereby demonstrating the influence of in vitro endophytic microorganisms in the development of microplants, and the importance of maintaining it in equilibrium with endophytes/ microplants.

Xenia, the transmission of traits from the pollinizer to the female's tissues, is a phenomenon hitherto unknown in tomatoes. Here, we describe xenia effects on the seeds and fruits of Solanum lycopersicum, the tomato, elicited by S. galapagense. The wild tomatoes, such as S. galapagense, have highly pilose fruit surface and minute seeds, unlike the domesticated species. Crossings between S. galapagense (pollinizer) and two large-seeded, glabrous cultivars of S. lycopersicum (females) tested the former's ability to raise the trichome density and trichome-to-1000-cell ratio and to reduce the seed weight in the latter's fruits. Selfed fruits of the two cultivars, Micro-Tom and Pusa Ruby, were compared to the crossed fruits. The pollen of S. galapagense was able to raise pilosity and to reduce seed weight in the crossed fruits of both cultivars, but with different magnitudes: seed reduction was more intense in Pusa Ruby, while pilosity increase was greater in Micro-Tom, both of which characterize xenia. Pilosity increase is not completely dependent on variation in epidermal cell density, which displayed no xenia effect. The difference between the maternal cultivars in the magnitude of pilosity increase may be due to the higher dilution of a putative male chemical signal (either hormone or RNA) in the larger fruits of Pusa Ruby. However, one cannot use the signal diffusion hypothesis to explain the xenia effects on seed weight.