FLOWER DIMORPHISM AND SELF-INCOMPATIBILITY INNARCISSUS TAZETTAL.

Abstract

Natural populations of Narcissus tazetta L. series bicolores Baker have been found in Israel to consist of plants having two floral types: short-styled and long-styled. In short-styled plants the stigma level is below the lower tier of anthers; in the long-styled plants it is usually at the height of the upper anthers, but may also be situated at any height between the two tiers of anthers or even above the upper one. While each of the two floral types displays variability in style length, there is an apparent discontinuity between them (fig. 1). The height of the anthers also fluctuates widely; however, there is no difference in anther level between the two types. Breeding experiments were carried out during 1957-1961 on plants sampled from natural populations growing in the coastal plain and the Judean hills of Israel. Self-pollination.-Upon selfing the plants proved to be completely sterile or almost so. Cross-pollination.-Crosses between the two floral types were found to be fertile. But significantly, and contrary to other dimorphic plants, crosses between plants of the same floral type were also fertile. Crosses were carried out with 52 shortstyled plants (434 flowers pollinated) and with 90 long-styled ones (507 flowers pollinated). The majority of crosses were compatible and several dozens of seeds per capsule were produced. Inheritance of the flower dimorphism.F1 seeds obtained from various cross-pollinations were sown in October, 1959. A few plants flowered in winter 1961-1962, others not until winter 1962-1963, and the following segregation has been obtained from the 1,035 plants checked: