Stimulation of embryogene-sis and haploid production in Brassica campestris anther cultures by elevated temperature treatments. Theor. Haploid Production in Higher Plant. 1* Vijay Kumar Mishra. Department of Bioscience IIIT Nuzvid. Rajiv Gandhi University of Knowledge. Technologies Nuzvid. A doubled haploid (DH) is a genotype formed when haploid cells undergo chromosome doubling. Artificial production of doubled haploids is important in plant.


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Doubled haploidy

Suitable methods are already well established for a number of important crops. However, many problems, related to regeneration frequency, gametoclonal variation and haploid production, are still unsolved. It is now clear that haploids and dihaploids form the ideal system for genetic manipulation in plants.

Although haploid production potential of DH populations in quantitative genetics has been understood for some time, it was the advent of molecular marker maps that provided the impetus for their use in identifying loci controlling quantitative traits.

As the quantitative trait loci QTL effects are small and highly influenced haploid production environmental factors, haploid production phenotyping with replicated trials is needed. This is possible with doubled haploidy organisms because of their true breeding nature and because they can conveniently be produced in large numbers.

Using DH populations, quantitative traits have been mapped in nine crop species.

In vitro production of haploid plants.

A problem in this procedure haploid production being able to identify the lines carrying the trait of interest at each generation. The problem is particularly acute if the trait of haploid production is recessive, as it will be present only in a heterozygous condition after each backcross.


The development of molecular markers provides an easier method of selection based on the genotype marker rather than haploid production phenotype. Combined with doubled haploidy it becomes more effective.

Doubled haploidy - Wikipedia

In marker assisted backcross conversion, a recipient parent is haploid production with a donor line and the hybrid F1 backcrossed to the recipient.

The resulting generation BC1 is backcrossed and the process repeated until the desired genotypes are produced. The combination of doubled haploidy and molecular marker provides the short cut. In the back cross generation one itself a genotype with the character of interest can haploid production selected and converted into homozygous doubled haploid genotype.

Bulked segregant analysis BSA [ edit ] In bulked segregant analysisa population is screened for a trait of interest and the genotypes at haploid production two extreme ends form two bulks. Then the two bulks are tested for the presence or absence of molecular markers.

In vitro production of haploid plants.

Since the bulks are supposed to contrast in the alleles that contribute positive and negative effects, any marker polymorphism between the two bulks indicates the linkage between the marker haploid production trait of interest.

BSA is dependent on accurate phenotyping and the DH population has particular advantage in that haploid production are true breeding and can be tested repeatedly.


DH populations are commonly used in bulked segregant analysis, which is a popular method in marker assisted breeding. Genetic maps[ edit ] Genetic maps are very important to understand the structure and organization of genomes from which evolution patterns and syntenic relationships between species can be deduced.

Haploid production populations have become standard resources in genetic mapping for species in which DHs are haploid production available.

Production of Haploid Plants (With Diagram)

Doubled haploid populations are ideal haploid production genetic mapping. It is possible to produce a genetic map within two years of the initial cross regardless of the species. The process of in vitro androgenesis for the ultimate production of haploid plants is haploid production in Fig.

The cultured microspores mainly follow four distinct pathways during the initial stages of in vitro androgenesis.