Note from the Editor

La publicación del Volumen XXXII (2) 2021, sobre mejoramiento genético de plantas y animales en la Argentina, tuvo como objetivo dejar registro de los objetivos, métodos, avances y logros de algunos programas consolidados, como reconocimiento a la relevante tarea realizada por los mejoradores y en cuanto ejemplos para futuras generaciones de la aplicación de los principios y métodos de la Genética en el desarrollo de germoplasma básico y de productos genéticos comerciales.

En el presente fascículo se continúa con el tratamiento del tema en otras especies de plantas cultivadas para consumo humano o animal, en cuyos programas de mejoramiento genético se han aplicado métodos clásicos de selección, hibridación, y retrocruzamientos basados en el conocimiento de la herencia Mendeliana. Asimismo, y dada la incorporación de la biotecnología en el mejoramiento genético, se discute la importancia de la correcta interpretación de la información genotípica para desarrollar estrategias prácticas de “mejoramiento molecular”  a fin de dar respuesta a necesidades reales de los programas.

Elsa L. Camadro

ARTICLE 1 - research

EXPANSION OF THE BASIC KNOWLEDGE ON THE INHERITANCE OF CHARACTERS THAT ALLOW THE DEVELOPMENT OF NEW MAIZE BREEDING TECHNIQUES
EXPANSIÓN DE LOS CONOCIMIENTOS BÁSICOS DE LA HERENCIA DE CARACTERES QUE POSIBILITEN DESARROLLAR NUEVAS TÉCNICAS DE MEJORAMIENTO EN MAÍZ

Salerno J.C., Kandús M.V., Prada A., Almorza D.

In order to increase the efficiency of maize hybrid seed production it is necessary to achieve a high grain yield to reduce production costs. This goal requires an expansion of the basic knowledge of the inheritance of characters in order to develop new breeding techniques to improve experimental materials with hard endosperm (flint). The balanced lethal system allows to study the relative contribution of different chromosome segments to hybrid vigour due to the heterozygosity of certain chromosome segments while the rest of the genome becomes homocygotic through continuous selfing. In this way, these segments can be transferred to inbred lines in order to increase grain yield or tassel size (to increase pollen production). The goal of this study was to transfer a heterotic segment by using a balanced lethal system regulated line (BLS14), through crosses and backcrosses, to S₅ flint lines derived from two commercial hybrids, ACA 2000 and Cóndor with closed pedigree, with the objective of increase grain yield or tassel size for pollen production. The analysis of variance (ANOVA) and principal components analysis (PCA) showed a significant improvement in grain yield and tassel size in the S₅ flint lines of both commercial hybrids, carrying the heterotic segment of the BLS14 line.

Key words: maize, heterotic segments, grain yield, inbred lines
Language: Spanish

ARTICLE 2 - research

HISTORY AND PROSPECTS OF FODDER CORN BREEDING IN ARGENTINA
HISTORIA Y PERSPECTIVAS DEL MEJORAMIENTO GENÉTICO DEL
MAÍZ FORRAJERO EN LA ARGENTINA

Rimieri P.

Corn is used to massively produce food for humans and domestic animals with grains of various taxonomic entities or races. For domestic ruminants, the whole plant is also used as forage. In Argentina, both corn grain and whole-plant silage are used for beef and dairy cattle production. This paper aimed to develop the history and perspectives of corn grown for grain and silage, focusing on plant breeding. The importance of corn fodder in its two variants (grain and whole-plant silage) has varied over time. We emphasize herein the importance of the specific genetic breeding of corn used for whole-plant silage to achieve higher yield potential and nutritional value than grain hybrids. The four population genetic structures used over time as cultivars, which determined the evolution of the technological process of selection and breeding, were analyzed. Based on the research carried out, seed companies have incorporated our protocols into their development and breeding programs. The contribution of selection and breeding in Argentina was effective in transforming the corn plant into ruminant feed, and this will increase with the development of specific silage hybrids.

Key words: cultivars, corn fodder, plant breeding
Language: Spanish

ARTICLE 3 - research

EL MEJORAMIENTO GENÉTICO DE CEBADILLA CRIOLLA (Bromus catharticus Vahl) EN ARGENTINA: SÍNTESIS DE LOS LOGROS Y AVANCES
THE GENETIC IMPROVEMENT OF PRAIRIE GRASS (Bromus catharticus Vahl) IN ARGENTINA: SYNTHESIS OF ACHIEVEMENTS AND ADVANCES

Martínez E.S., Rimieri P.

The prairie grass (Bromus catharticus Vahl) is the annual/biennial native forage grass of temperate climates of most importance and diffusion in Argentina. Several authors have studied the phenotypic variability in morphophysiological characters in cultivars and native populations of prairie grass. The first commercial cultivars were heterogeneous populations that were considered the best adapted in the temperate region of Argentina. Genetic, agronomic and molecular characterization of the selection base populations and of the germplasm conserved in the active bank of INTA Pergamino, contributed to knowing and conserving the available genetic diversity and, at the same time, provided usable genetic variability in breeding. The most representative cultivars considered in this work were Pergamino Martín Fierro MAG; Fierro Plus INTA, Bar INTA 200, Rosalía INTA and INTA Calvu, in which technological packages associated with the utilization in animal production were developed.

Key words: prairie grass, cultivars, germplasm, plant breeding
Language: Spanish

ARTICLE 4 - research

THE IMPORTANCE OF DEEP GENOTYPING IN CROP BREEDING
LA IMPORTANCIA DEL GENOTIPADO PROFUNDO EN EL MEJORAMIENTO GENÉTICO

Zambelli A.

One of the greatest challenges facing humanity is the development of sustainable strategies to ensure food availability in response to population growth and climate change. One approach that can contribute to increase food security is to close yield gaps and enhancing genetic gain; to such end, what is known as “molecular breeding” plays a fundamental role. Since a crop breeding program is mainly based on the quality of the germplasm, its detailed genetic characterization is mandatory to ensure the efficient use of genetic resources and accelerating development of superior varieties. Deep genotyping is an essential tool for a comprehensive characterization of the germplasm of interest and, fortunately, the technology is now accessible at a reasonable cost. What must be ensured is the correct interpretation of the genotypic information and on that basis develop efficient practical molecular crop breeding strategies that respond to the real needs of the breeding program.

Key words: breeding population, genetic resources, marker assisted selection, Single Nucleotide Polymorphism (SNP)
Language: English

Note from the Editor

ETHICAL ISSUES IN SCIENTIFIC PUBLICATION
CUESTIONES ÉTICAS EN LA PUBLICACIÓN CIENTÍFICA

Elsa L. Camadro