WebThrum plants are heterozygous (Ss) and pin plants are homozygous (ss). Reciprocal crosses between the two forms are required for fertilization; within-morph crosses are impeded by … WebAug 12, 2024 · In a pin-eyed flower the stamens are lower down than the stigma in the floral tube. In thrum-eyed flowers, the style is shorter and the stamens higher, so that the stigma is far beneath the stamens. Pollen must travel from a stamen to a stigma, and attach to the stigma, to effect pollination.
The Plant Journal 51 Identification and characterization of …
WebFeb 25, 2024 · The two forms are known as ‘Pin’ and ‘Thrum’. In ‘Pin’ flowers the stigma is at the top of the flower tube with the anthers positioned halfway down. In ‘Thrum’ flowers the stigma is positioned halfway down with the anthers at the top. Individual plants have either Pin flowers or Thrum flowers. WebMar 2, 2024 · The pin and thrum forms of the primrose flowers were described by Charles Darwin, back in the 1860’s. He also observed that the pollen from the pin flowers was smaller than that produced by the thrum flowers. He carried out breeding experiments with the different primroses [crossing thrum with thrum, thrum (male) with pin, pin (male) with ... fema mt-ez form
Primroses – heralds of spring - Woodlands
WebThe transcriptomics analysis of the pistils revealed 1311 and 1048 differentially expressed genes (DEGs) that were identified by comparing pin self-pollination (PS) vs. pin cross … WebHow a heterostylous plant species responds to life on remote islands: a comparative study of the morphology and reproductive biology of Waltheria ovata on the coasts of Ecuador and the Galápagos Islands Webthrum X pin (seed parent is mentioned first). Pin X pin was less infertile, giv-ing about one-third of the seeds per pollination of a pin X thrum cross. Data for P.- vulgaris are scanty, but the ille-gitimate thrum pollination seems to be as infertile as in P. veris; the illegitimate pin pollination may be almost fully fertile fema mechelen