User:M.zakieh/sandbox

Speed breeding in disease resitance programs

Background

Breeding material from breedings program are often well adapted to the growing conditions and is most suitable for cultivar development. The breeding material benefits by introducing slightly genetically diverse material to it. It brings in new genes to the collection and helps in maintaining the relatively broad diversity in the breeding material. On the other hand, the genebank germplasm collection is often composed of old cultivars and landraces which has high genetic diversity. However, the genebank germplasm is not usually well adapted to the local growing conditions and often have low yields. Thus, an optimal way to utilize and benefit from the genebank germplasm is to identify the genotypes with desirable traits such as disease resistance and then cross them with the breeding lines. Thereafter, only keep those progeny lines that show high disease resistance coming from the genebank germplasm and high yield coming from the breeding line parent. Shortening the growth cycle of winter wheat while at the same time evaluate the plants for disease resistance is usually carrued out in grwoth chambers and greenhouses. Being able to do so will help in deciding which plants to throw away early on in a breeding program. This will lead to both cost and time benefits. Disease resistance breeding protocol implementing a technique named Speed breeding (SB) is usually carried out on collection of winter wheat germplasm or wheat crosses (populations).At a later stage the plants are infected with the disease causing agent. Fusarium head blight, is one of the first diseases test using this protocol.

It is estimated that 30–50 % of winter wheat growth cycle can be reduced in greenhouse compared to field growth without any adverse growth affects. This is a dramatic reduction in time as the protocol can enable the evaluation of three generations of wheat for FHB disease resistance within just one year instead one per year in the field.

To cross validate the results of the phenotypic evaluation of diseaese resistance using the, it is recommended to run genome wide association studies GWAS to associate the visual findings with genetic background of the material for resistance. The protocol leads to an acceptable evaluation of disease resistance in plants, and breeding markers from the study. Taken together, the visual evaluation for FHB combined with the results of the genetic tests confirm that the protocol is reliable in FHB resistance breeding for winter wheat were developed. The protocol opens the way to use it for breeding winter wheat against other diseases up in the adult stages of growth. The protocl was orginaly developed in the Swedish University of Africutlural Sciences (SLU), Department of plant breeding in Alnarp by Aakash Chawade group involving PhD student Mustafa Zakieh. The development of the protocol was in collaboration with the Swedish agricultural cooperative Lantmännen. The protocol will be implemnted in Lantmännen's  breeding programs.