Showing papers on "Molecular breeding published in 1997"

Molecular breeding in the genus Musa: a strong case for STMS marker technology

Abstract: Musa species are among the tallest monocotyledons and include major food-producing species. The principal cultivars, derived from two major species Musa acuminata (‘A’ genome) and Musa balbisiana (‘B’ genome), are polyploid hybrids (mainly AAA, AAB and ABB triploids), medium to highly sterile, parthenocarpic and clonally propagated. Bananas and plantains are crops to which molecular breeding is expected to have a positive impact. In order to better understand banana genetics, more knowledge has to be accumulated about the complex genome structure of hybrids and cultivars. Therefore, the aim of our work is to develop molecular markers that are codominant, reliable, universal, highly polymorphic and that are applicable to collaborative Musa germplasm genotyping and mapping. Two size-selected genomic libraries have been screened for the presence of simple sequence repeats (SSR). Our data demonstrate that SSR are readily applicable to the study of Musa genetics. Our comprehensive analyses of a significant number of banana sequence tagged microsatellite sites (STMS) will add to our knowledge on the structure and phylogeny of genomes of the Musa species, and suggest that microsatellites be used as anchor markers for a banana genetic core map. Additional markers, such as e.g. CAPS have also been tested in order to increase the detection of polymorphisms exceeding that revealed by STMS technology. The utility of PCR-derived markers for collaborative genetic analyses of the banana genome, and the transferability of 'streamlined’ laboratory techniques and data analysis to Developing Countries are discussed.

Applications of AFLP™ in plant breeding, molecular biology and genetics

Abstract: The recently developed molecular marker systems based on DNA amplification have facilitated and enhanced fundamental and applied biological studies. Among all established methods, AF;LP (Amplified Fragment Length Polymorphisms) has proven to be a highly reliable and reproducible technique that can easily be adapted and used for a variety of applications ranging from molecular biology studies to usage in crop improvement and breeding programs. In this overview, a brief comparison between the most commonly used molecular marker systems is made and several applications of the AFLP technique are described.

Highly iron-containing plant produced by molecular breeding and method for producing the plant

Abstract: PROBLEM TO BE SOLVED: To increase the iron content in a plant by molecular breeding SOLUTION: A plant cell having an extraneous ferritin gene (eg soybean ferritin cDNA) which has been transduced in an expressible state A plant (eg lettuce) having the plant cells in which extraneous ferritin genes have been transduced in an expressive state A progeny (eg seed) derived from the plant and still able to express the extraneous ferritin gene The extraneous gene is transduced into a plant cell to obtain a transformed plant cell, and the transformed plant cell is regenerated into a plant Thus, a plant increased in iron content is obtained A plant transformant having a plant cell into which an extraneous ferritin gene has been transduced is prepared, and then the plant cells among the transformants are made to express the extraneous ferritin genes Thus, the iron contents in the plant cells are increased

Trends of Genetic Study of Forest Tree and Development of Useful Traits for Apple Biotechnology

Abstract: Forest trees have long generation times and arc highly heterogeneous, so few extended pedigrees are available. Because of these limitations, there is a greater potential for DNA-markers to improve genetic analysis and to accelerate breeding in forest trees. In deciduous fruit plants, the most important traits are fruit qualities such as acidity, sugar content, fruit size, and total yield. As these are quantitative traits that appear to be controlled by a number of loci, it is difficult to make progress in the quick improvement of fruit quality, requiring the elucidation of the position and function of QTLs affecting these traits. Although QTL analysis is important for genetic enhancement, it is time consuming work. Also, for many years until now, DNA-markers have not been applied to practical tree improvement because of technical and theoretical limitations. High levels of heterozygosity and linkage equilibrium of markers in populations were considered to be serious limitations. Now, it is carefully suggested that molecular breeding should be primarily based on the cloning and characterization of useful agronomic traits for direct application to forest tree plants.For example, a monogenic trait that specifically contributes to flower and fruit development is useful for control of thinning. Biotechnology is likely to give valuable genetic improvement of tree species and the adopted strategy based upon biotechnology provides a model system in similar studies for other fruit and woody species.