PJB-2024-267
EFFECTIVE IN VITRO REGENERATION SYSTEMS FROM LEAF EXPLANTS FOR COMMERCIALLY IMPORTANT PEAR CULTIVARS (PYRUS COMMUNIS L.)
Margarita Keldibekova
Abstract
One of the disadvantages of creating new pear cultivars is the long duration of the breeding process, which is associated with such a biological feature of the crop as a long period of juvenile development and, as a result, the late entry of hybrid seedlings into fruiting. Breeding Programs are still focused on creating new improved cultivars and rootstocks of pears, however, breeders have difficulties solving specific problems of the cultivar without losing its main advantages. One of the modern methods that can significantly speed up the breeding process and create genotypes with desired properties is genetic transformation, which provides an alternative way to clarify the function of genes and is suitable for purposeful improvement of both individual traits and new plant properties. One of the possible and most frequently used methodological approaches for the introduction of genetic constructions into the genome is agrobacterial transformation.
For pear (Pyrus communis L.), the transformation was achieved using various types of explants, but its effectiveness depended very much on the cultivar. Breeders were successful in transferring desirable genes to such cultivars as Burre Bosc, Conference, Doyenne du Comice, and Passe-Crassane, however, the frequency of agrobacteria-mediated transformation of pear cultivars was quite low, since high values of regeneration frequency were not always reproducible. In this regard, the creation of a stable and effective in vitro regeneration system is a basic requirement for the success of the genetic transformation of pears. Many reports describe that a large number of factors affect the organogenesis of pear leaves, including the choice and orientation of the initial explant, plant growth regulators (especially cytokinins) and their concentration, the basic salt composition of the medium for the induction of shoots, gelling agents, type of carbohydrates and genotype. Also, only a few authors describe the sensitivity of pear explants to disinfecting and selective antibiotics.
The goal of this review is to collect, summarize and present up-to-date data on effective and reproducible in vitro regeneration protocols. The review includes detailed information on the optimal formulations of culture media, concentrations of growth regulators and antibiotics for the main commercial pear cultivars grown worldwide. The results of this review will be useful in the development of genetic transformation protocols for the application of basic new genomic technologies (NGTs) for the genetic improvement of pears.
To Cite this article:
Download
