Meloydogine incognita (Nematoda) reproduction affected by plants overexpressing a steroid inducible gene-expression system

Abstract

a b s t r a c tThis study reports the impact of an integral glucocorticoid expression system (GR-system) on plant and plant-nematode reproduction. Seedlings expressing a GR-system (transGRþ) show affections of growth and development. It is well-known that plant-hormones such as gibberellins, auxins and steroids are essential for developmental and physiological processes, in biotic/abiotic stresses. Here is shown some phenotypic affections reported by tobacco expressing a whole mammalian GR-system, how those effects are rescued by external hormonal treatments and the influence on plant-nematode fecundity. Results demonstrate that: i) GR-system is constitutively expressed in plants and its functionality proved by the activation of the reporter-gene transcription (uidA) after induction with different steroid hormones, dexamethasone (DEX) and progesterone (PRO) as well; ii) transGR þ growth affected at hypocotyls and roots development result mitigated by exogenous hormones applications; iii) no differential expression in the expansin-gene TExp4 assayed; iv) Significant reductions of J2-larvae assessed in the egg-masses and soil during the generations on transformed plants. Although the molecular mechanism behind these results is still unknown, all together these results suggest a role of GR as reflected by the impact on the plant development and reduction of Meloydogine incognita (Nematoda) second-stage juveniles in egg-masses and soil.