Shed Pollen Culture inHordeum vulgare

Anthers of Hordeum vulgare cv. Sabarlis at the mid-unicellular pollen stage, pretreated in the excised spike for 14 d at 7 °C, dehisce within 24 h of being floated on the surface of liquid medium. About half the pollen (1500 grains per anther) is liberated into the medium. If the anthers are then removed and the cultures re-incubated, calluses develop from the shed pollen in high yields. At low anther densities, 10p–20 (1–3 × 104 grains) per ml, medium preconditioned by anthers and supplemented with m-inositol (1000 mg 1−1) is required, but at high densities, 120 anthers (2 × 105 grains) per ml, preconditioning is less important, the cultured anthers themselves having a sufficient conditioning influence. Large-scale dissection of anthers can be avoided by use of drops of medium, the volume being increased gradually as culture proceeds. Pollen remaining in the anthers after 3 d gives rise to calluses if isolated mechanically and cultured in the inositol medium. The use of shed pollen is seen as particularly valuable for culture in species whose anthers are small, tedious to dissect out and difficult to process without severe damage.