Dynamics of inorganic ions in microspore and pollen grain during development of the tobacco male gametophyte

We studied the dynamics of mobile potassium, chloride, and nitrate ions during development of the microspore and differentiation of the pollen grain inNicotiana tabacum L. by measuring their concentration in aqueous extracts from cells destroyed by freezing-thawing using ion-selective electrodes. Stage-specific changes in the ion content and intracellular concentration in the male gametophyte were found. A relationship of the dynamics of ions to growth processes and changes in metabolic activity during gametophytogenesis has been discussed. The changes in the potassium and chloride ion concentrations have been interpreted as regulatory changes controlling protein synthesis in the pollen grain vegetative cell. Deceased.     

Intracellular Concentrations of Potassium,Chloride, and Protons during Differentiation of Tobacco Male Gametophyte

Changes in intracellular pH, K⁺and Cl^–concentrations were measured in pollen grains, anther loculi, and whole anthers during in vivodifferentiation of male gametophyte of Nicotiana tabacumL. The effects of extracellular K⁺and Cl^–on intracellular pH regulation were also studied during development of pollen grains in vitro. Ion-selective electrodes and X-ray microanalysis were used to measure ion concentrations, and microfluorometry was used to measure pH. The intracellular pH and [K⁺] decreased at the mid- and late binucleate stages of pollen grain development, while [Cl^–] increased. At the same stages, K⁺and Cl^–concentrations in locular liquid were found to increase. The intracellular pH in pollen grains, isolated at the mid-binucleate stage, decreased during in vitrodevelopment in the medium containing 50 mM KCl. It was suggested that changes in ionic composition of the external medium can regulate the intracellular pH during development of pollen grain in vivo.     

Inorganic ion dynamics in the microspore and pollen grain of tobacco during the development of the male gametophyte

We studied the dynamics of mobile potassium, chloride, and nitrate ions during development of the micro-spore and differentiation of the pollen grain in Nicotiana tabacum L. by measuring their concentration in aqueous extracts from cells destroyed by freezing-thawing using ion-selective electrodes. Stage-specific changes in the ion content and intracellular concentration in the male gametophyte were found. A relationship of the dynamics of ions to growth processes and changes in metabolic activity during gametophytogenesis has been discussed. The changes in the potassium and chloride ion concentrations have been interpreted as regulatory changes controlling protein synthesis in the pollen grain vegetative cell.