Monosomic analysis of heading date and spikelet number in the common wheat (Triticum aestivum L.) multispikelet line 'Noa'.

Genetic analysis of heading date and spikelet number was carried out in the common wheat (Triticum aestivum L.) multispikelet line 'Noa', by using the monosomic series of the regular line 'Mara'. 'Noa's' high number of spikelets was found to be controlled by a recessive major gene on chromosome 2D; a slight reduction in spikelet number was induced by another recessive gene on 'Noa's' 7A chromosome. 'Noa's' late heading date was found to be controlled by two recessive genes, located on chromosome 2D (a major effect) and 6B (a minor effect). The nature of the genes located on 'Noa's' 2D chromosome and the relationship between spikelet number and heading date are discussed.