Self-incompatibility and male sterility in six Matricaria recutita varieties

Abstract

On purpose to develop suitable mother lines for a large scale hybrid production of the medicinal crop species Matricaria recutita [L.] Rauschert investigations - to determine the proportions of self and cross fertilization, - to identify self-incompatible genotypes and - to observe spontaneous or induced male sterility were undertaken. The seed production per flower head under isolated and under untreated control-conditions was evaluated in six German chamomile varieties. Under assumption of equal behaviour of plants concerning their reproduction rate results showed opposed reactions of the auto-tetraploid ‘Manzana’ and the diploid ‘Degumille’ to isolation. Moreover, slightly significant interactions between cultivars and treatment concerning seed production per flower head indicate the influence of isolation being cultivar specific. An average of 22 % of self-fertilization under open pollination conditions is displayed over all cultivars. Highly significant differences between cultivars reveal cultivar specific self-incompatibility, at which the diploid varieties ‘Bona’ and ‘Degumille’ exhibit the highest levels of 25 % and 28 %, respectively. 9 of 1105 plants showed spontaneous single flower head aberrations indicating possible tendencies to male sterility. Spontaneous pollen sterility, estimated after aceto-carmine staining, reached mean levels between 0.5 % (‘Bona’) and 2.4 % (‘Lutea’). The progeny after crossings across all six varieties showed an average of 10.20 % pollen sterility indicating a tendency of increasing pollen sterility by intra-specific crossings. Nevertheless, as the best way to raise suitable mother lines the development of vegetatively propagated self-incompatible diploid genotypes can be recommended.