Immature tassels as alternative explants in somatic embryogenesis and plant regeneration in south Brazilian maize genotypes

Magali Ferrari Grando,Luiz Ricardo Pereira,Madelaine Lourdes Varnier,Marilia Rodrigues De Silva,Marilei Suzin,Beatriz Marti Emydgio

doi:10.4025/actasciagron.v35i1.15545

Magali Ferrari Grando, Luiz Ricardo Pereira + Show 4 more

Open Access

https://doi.org/10.4025/actasciagron.v35i1.15545

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Abstract

Somatic embryogenesis and in vitro plant regeneration are fundamental processes in the obtainment of transgenic maize plants. Explant, genotype and culture medium are determining factors in these processes. Immature embryo explants and the American Hi-II genotype have been widely employed to acquire genetically modified plants in this species. However, the use of more readily available explants is desired as well as the development of genetic transformation protocols for productive genotypes adapted to local conditions. This study provides an evaluation of immature tassel explants in relation to embryogenic callus production and plant regeneration in South Brazilian maize genotypes for their use in genetic transformation experiments. Immature tassels from 5 hybrids were cultivated in different callus-induction media. The frequency and the fresh mass of embryogenic calli were evaluated. The frequency was influenced by genotype, and the fresh mass was influenced by genotype and culture medium. In plant regeneration, shoots, complete seedlings and acclimatized and fertile plants were quantified. Treatments producing long term embryogenic calli from immature tassels of South Brazilian genotypes with the capacity to regenerate were identified.

Highlights

Maize is a liliopsida of great agricultural importance for the South Region of Brazil, and it is increasingly requested due to the expansion of activities associated with industrialization and animal exploitation.Products molecularly improved from this species are already being cultivated in Brazilian farms
Indirect somatic embryogenesis has been the morphogenetic process of preference in the regeneration of transgenic plants (FRAME et al, 2002, 2006, 2011; HUANG; WEI, 2005; ISHIDA et al, 2007; VEGA et al, 2008; ZHAO et al, 2001)
To accelerate the obtainment process of in vitro plants for genetic manipulation, this study evaluated the immature tassel response of 5 South Brazilian maize genotypes in 4 different culture media in relation to the capacity of embryogenic callus production and growth as well as the regeneration of plants from these calli

Summary

Introduction

Maize is a liliopsida of great agricultural importance for the South Region of Brazil, and it is increasingly requested due to the expansion of activities associated with industrialization and animal exploitation.Products molecularly improved from this species are already being cultivated in Brazilian farms. Genetic engineering has permitted the introduction of genes into maize that improve its nutritional value (CARNEIRO et al, 2000; GRANDO et al, 2005; NAQVIA et al, 2009; ZHU et al, 2007) and tolerance to important abiotic stresses due to drought or cold temperature (AL-ABED et al, 2007; SHOU et al, 2004; ZHANG et al, 2005). 39-47, Jan.-Mar., 2013 protocols because the gene is introduced at the level of topipotent cells, and the plants can be regenerated from these cells. Indirect somatic embryogenesis has been the morphogenetic process of preference in the regeneration of transgenic plants (FRAME et al, 2002, 2006, 2011; HUANG; WEI, 2005; ISHIDA et al, 2007; VEGA et al, 2008; ZHAO et al, 2001)

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