Stimulation of growth of culturedNicotiana tabacum W 38 pollen tubes by poly(ethylene glycol) and Cu(II) salts

摘要: Growth of pollen tubes ofNicotiana tabacum W 38 in a defined liquid medium buffered at pH 5.9 and containing sucrose, amino-acids, boric acid, salts an antibacterial agent was stimulated by the addition poly(ethylene glycol) 6000 (PEG-6000) Cu(II) salts. In absence both these supplements, up to 50% hydrated grains did not develop further, germinated were slow-growing abnormal, with thickened walls, kinked growth, fragile, swollen tips granular cytoplasm. Addition 10–15% (w/v) purified PEG-6000 increased germination 80–90% prevented progressive bursting tube tips, but growth still slow remained swollen. 30 μM CuSO4 stimulate or prevent tip bursting, produced straight-growing smooth-sided resembling growing through stylar tissue; free Cu2+ concentration under conditions about 1.0 due chelation similar morphologies obtained 1.0–1.5 added when NH4Cl replaced amino-acids. When amino-acids supplemented 12.5% CuSO4, long-term (48 h) straight thin walls long ladders callose plugs observed; occurred 250 μm/h, approximately 30–40% rate observed style. Although omission from this complete severely affected plug deposition, it alter timing generative-nucleus division, thus different parameters associated second phase pollen-tube can be uncoupled culture. High levels FeSO4 (300 μM) had morphogenetic effect 300 L-ascorbate D-iso-ascorbate required precipitation Fe(III) oxide prolong stimulation growth; EDTA removed FeSO4. Further, impure grade PEG-4000 contaminated organic morphogen that allowed continued smooth, straight-sided FeSO4, morphology unaffected ascorbate EDTA. However, trace suggests play important role development least species ofNicotiana.