Culture conditions for efficient induction of green plants from isolated microspores of barley
Subculture regime and carbohydrate concentration of the medium had a marked effect on the regeneration of green plantlets from mechanically isolated microspores of Hordeum vulgare L. cv. Kymppi. A sevenfold increase in the yield of green plants was obtained by shortening the suspension culture time of the developing proembryo mass from 4 to 3 weeks. A further twofold increase was obtained by increasing the maltose concentration of the microspore isolation medium and of the culture medium. Under optimal conditions, a mean of 169±97 green plants per spike were regenerated.
Haploidy in barley
Barley was one of the first crops to be cultivated by man (Zohary & Hopf, 1988), and today ranks as the fifth most productive crop in the world. Factors which have contributed to its successful cultivation include its tolerance to abiotic stresses; high and low temperatures, drought, mineral deficiencies and toxicities, and its relatively short life cycle. These factors enable barley to be grown in extreme environments not suited to other crops. The main harvestable product is the grain which is used for animal feed, brewing, malting, and as a human food. The straw and foliage are also important sources of animal fodder.
Development of Pollen Embryoids in Anther Cultures of Datura innoxia II. EFFECTS OF GROWTH HORMONES
In anther cultures of Datura innoxia the addition of growth hormones, such as auxins, gibberellins, and cytokinins, to the culture medium enhanced the production of pollen embryoids. Cytokinins appeared to be the most effective and, among the four cytokinins tested, zeatin and kinetin gave the best results. Generally speaking, combinations of hormones did not improve the response over that of an individual hormone. The number of embryoids per anther varied in the same medium and did not strictly correlate with the percentage of respond ing anthers.