Perspetiva europeia de melhoramento e propagação de macieira em agricultura biológica no âmbito do projeto LIVESEED

A maçã é um dos frutos de maior destaque na fruticultura europeia. No entanto, a sua produção em Agricultura Biológica (AB) é um desafio constante, dada a problemática associada à proteção das culturas, num quadro de forte limitação à aplicação de produtos fitossanitários. Deste modo, torna-se necessária a produção de material vegetal melhor adaptado às condições edafoclimáticas e ao modo de produção biológica. O objetivo do LIVESEED é melhorar o desempenho e a sustentabilidade em AB, impulsionando os esforços de produção de diásporos e de melhoramento de plantas em modo de produção biológica

In vitro germination of immature embryos for accelerating generation advancement in peppers (Capsicum annuum L.)

[EN] Capsicum peppers are one of the most important vegetables in the world and continuous breeding efforts are required to improve yield, resistances, or fruit traits. In this sense, breeding programs usually last many years because many generations each with several months are needed. Therefore, the isolation and in vitro germination of immature embryos might be helpful to shorten breeding cycles and accelerate breeding programs. Here, we evaluated the efficiency of this strategy in Capsicum annuum under both Autumn-Winter (AW) and Spring-Summer (SS) growing conditions. Five accessions, representing different varietal types, were included in this experiment and immature advanced embryos (torpedoearly cotyledonary) were used because of their high in vitro germination aptitude. Conventional breeding cycles (control) ranged between 148 and 184 days in AW and between 117 and 154 days in SS, indicating that no more than two generations per year are possible in peppers. By contrast, the in vitro strategy reduced the cycle length by 33-70 days in the AW season and by 13-56 days in the SS season, with California accessions showing the highest shortenings. These findings show that this strategy will allow Capsicum breeders to obtain three generations per year in California peppers, and up to four generations in cayenne peppers. Furthermore, compared to controls, in vitro-germinated plantlets showed the same high pollen fertility, and no deleterious effects were observed in their subsequent development (plant height and biomass). Therefore, these plants can be integrated safely in breeding programs. (C) 2014 Elsevier B.V. All rights reserved.Juan P. Manzur thanks Universitat Politecnica de Valencia for a research grant (2011-S2-4264, programa para la formacion de 209 personal investigador, FPI). Authors thank NEIKER and the Consejos Reguladores of D.O.P. Pimenton de Murcia and D.O.P. Pimiento del Piquillo de Lodosa for providing us with seeds of Guindilla de Ibarra, Bola and Piquillo, respectively. This work has been partially financed by INIA projects RTA2010-00038-C03-03 and RF2010-00025-00-00, FEDER funds.Manzur Poblete, JPA.; Oliva Alarcón, M.; Rodríguez Burruezo, A. (2014). In vitro germination of immature embryos for accelerating generation advancement in peppers (Capsicum annuum L.). Scientia Horticulturae. 170:203-210. doi:10.1016/j.scienta.2014.03.015S20321017

Growth regulators and darkness increase efficiency on in vitro culture of immature embryos from peppers

[EN] Common pepper (Capsicum annuum L.) is one of the most important vegetables in the world, and extensive breeding efforts are being made to develop new improved strains of this species. In this regard, in vitro culture of immature embryos may help breeders accelerate breeding cycles and overcome interspecific barriers, among other applications. In this study, we have optimized a protocol for in vitro culture of immature embryos of C. annuum. Levels of indole-3-acetic acid (IAA) and zeatin have been tested to improve the efficiency (germination rates) of this technique in C. annuum embryos at the four main immature stages (i.e. globular, heart, torpedo, and early cotyledonary) from four varietal types of this species (California Wonder, Piquillo, Guindilla, and Bola). The effect of 5-day initial incubation in the dark was also tested on the most efficient hormone formulation. On average, relatively low levels of both IAA and zeatin (0.01 mg L-1 each) (M-1) provided the highest germination rates, particularly in the advanced stages (torpedo and cotyledonary). To a lesser extent, the lack of these growth regulators (M-0) or high IAA (0.2 mg L-1)/low zeatin (0.01 mg L-1) (M-2) combination also had a positive response. On the contrary, high zeatin levels (0.2 mg L-1) produced very low germination rates or callus development (efficiency 0-7 %). Different responses were also found between genotypes. Thus, considering the best media (M-0, M-1, M-2), Bola embryos had the highest rates. M-1 plus 5-days of initial dark incubation (M-1-D) improved the efficiency rates at all embryo stages, particularly in the earliest (globular) embryos which increased from 3 % to > 20 %.Juan P. Manzur thanks Polytechnic University of Valencia for a research grant (2011-S2-4264, research staff training program, FPI). This work has been co-financed by INIA projects RTA2010-00038-C03-03 and RF2010-00025-00-00, and FEDER fundings. The authors thank NEIKER and the Regulatory Boards of D.O.P. Pimenton de Murcia and D.O.P. Pimiento del Piquillo de Lodosa for providing us with seeds of Guindilla de Ibarra, Bola and Piquillo.Manzur Poblete, JPA.; Calvache Asensio, MDLN.; Rodríguez Burruezo, A. (2014). Growth regulators and darkness increase efficiency on in vitro culture of immature embryos from peppers. Scientia Agricola. 71(6):488-493. https://doi.org/10.1590/0103-9016-2013-0230S48849371

ESICM LIVES 2016: part two : Milan, Italy. 1-5 October 2016.

Meeting abstrac