Efficient method for rapid multiplication of clean and healthy willow clones via in vitro propagation with broad genotype applicability

Abstract

Willow is a versatile crop with considerable potential as a source of renewable biomass for bioenergy. Although breeding new varieties takes less time compared with some other tree species, producing new willow varieties is still a slow, labour-intensive process, partly because clonally propagating the results of each cross is a bottleneck early in the breeding scheme. In this paper, we describe a facile, rapid method for the in vitro culture of a wide range of willow genotypes. We have developed a combination of media and methods for efficient tissue-culture propagation to rapidly multiply individual plants and simultaneously produce clean, stock germplasm applicable to a wide range of willow genotypes that can be phytosanitary tested to demonstrate their disease-free status. The micropropagation method described could generate in the order of 5000 viable, transplantable clones from a single plant in just 24 weeks and was used to produce phytosanitary tested breeding material for export to overcome restriction on the international transport of woody cuttings. This method could represent a valuable biotechnology adjunct to willow breeding programmes and could accommodate early selection via molecular or biochemical markers.Peer reviewe

Breeding progress and preparedness for mass‐scale deployment of perennial lignocellulosic biomass crops switchgrass, miscanthus, willow and poplar

“…Promising selections (i.e., potential cultivars) need to be clonally propagated. A rapid, in vitro tissue culture propagation method has been developed (Palomo‐Ríos et al, ). This method can generate about 5,000 viable, transplantable clones from a single plant in just 24 weeks.…”

“…An in vitro system can also accommodate early selection via molecular or biochemical markers to increase selection speed. Conventional breeding systems take 13 years via four rounds of selection from crossing to selecting a variety (Figure ), but this has the potential to be reduced to 7 years if micropropagation and MAS selection are adopted (Hanley & Karp, ; Palomo‐Ríos et al, ).…”

The Effect of Sucrose Supplementation on the Micropropagation of Salix viminalis L. Shoots in Semisolid Medium and Temporary Immersion Bioreactors

“…In addition, it is a known hyperaccumulator of metals and organic substances, making it a prime candidate for phytoremediation [11]. For these reasons, S. viminalis has been widely used in breeding programmes [9,10,12]. Good breeding efficiency requires seedlings from controlled crossings to be rapidly multiplied to produce sufficient clonal plantlets for replicated trials in a range of environments.…”

“…Good breeding efficiency requires seedlings from controlled crossings to be rapidly multiplied to produce sufficient clonal plantlets for replicated trials in a range of environments. S. viminalis roots easily, but it is often an advantage to accelerate plant multiplication of selected genotypes required for testing or distribution [12]. Some micropropagation protocols in a semisolid medium have been developed for S. viminalis and other willow species [12] and references therein.…”

“…S. viminalis roots easily, but it is often an advantage to accelerate plant multiplication of selected genotypes required for testing or distribution [12]. Some micropropagation protocols in a semisolid medium have been developed for S. viminalis and other willow species [12] and references therein. In our laboratory we explored its use as a model plant for our research in a liquid medium culture.…”