Breeding triploid aspen and poplar clones for biomass production

Abstract

Enriched diploid pollen was applied for in vitro pollinations and crossbreeding in the greenhouse to produce high performance triploid aspen and aspen hybrids for cultivation in medium rotation plantations. In addition to crossings within the section Populus, intersectional crossbreeding was performed to combine benefits of intersectional hybridization with those derived from triploidisation.Both the enrichment of diploid pollen by size fractionation of naturally unreduced pollen and heat treatment of microspore mother cells resulted in a distinct increase of diploid pollen. Using this pollen, six triploid plants were obtained from in vitro pollinations and twenty from crossbreeding in the greenhouse. The triploid plants displayed a high variability in growth performance. Two clones from in vitro pollination and five from crossbreeding in the greenhouse were chosen to estimate growth characteristics. A first assessment of clone performance in an outdoor container test con - ducted over one growing season revealed two triploid clones with a same stem height and a significantly increased basal stem diameter in comparison to the fast-growing triploid reference clone “Astria”. Crossbreeding experiments also resulted in two fast-growing mixoploid clones, which have already been stable for several years.All in all, in this study, crossbreeding using enriched diploid pollen is proved to be a reliable and applicable approach for an effective breeding of triploid poplars.

Microclonal reproduction of common aspen (Populus tremula L.) genotypes in the Republic of Tatarstan

“…This led to an increase in the average trunk volume by 3 times (table 4). Similar results of the predominance of giant aspen are found in the literature [5,[9][10][11][12][13]. Speed of aspen trees growth and their resistance to core rot are related.…”

“…Triploid aspens are characterized by increased adaptive capacity (65%) compared to diploid forms (30%). In continuation of these studies, highly productive, rot-resistant triploid genotypes of aspen in the forests of Tatarstan were selected in the republic, followed by their laboratory molecular genetic identification [10] and experimental plantations of fast-growing tree species were created.…”

Analysis of the Aspen Growth (Populus tremula L.) Obtained by in Vitro in the Republic of Tatarstan

“…This process led to an increase in the average volume of the trunk by three times (Fig. 7) [17,18]. The growth rate of aspen trees and their resistance to heart rot are related.…”

Polyploidy in Industrial Crops: Applications and Perspectives in Plant Breeding

“…Enriched diploid pollen was obtained by size fractionation of naturally unreduced pollen and heat treatment of microspore mother cells. In addition to crossings within the section Populus, intersectional crossbreeding was performed combining the benefits of intersectional hybridisation with those derived from triploidisation [144]. 2n pollen induction in P. x popularis made it possible to obtain polyploids in two sections other than Populus [145].…”