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NASA NTRS · 20040089923

Effects of shoot inversion on stem structure in Pharbitis nil

Prasad, T. K.·Sack, F. D.·Cline, M. G.
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Abstract

The effects of shoot inversion on stem structure over 72 hr were investigated in Pharbitis nil by analyzing cell number, cell length, and the cross sectional areas of cells, tissues, and regions. An increase in stem diameter can be attributed to an increase in both cell number and cross sectional area of pith (primarily) and vascular tissue (secondarily). Qualitative observations of cell wall thickness in the light microscope did not reveal any significant effects of shoot inversion on this parameter. The inhibition of shoot elongation was accompanied by a significant decrease in cell length in the pith. The results are generally consistent with an ethylene effect on cell dimensions, especially in the pith.

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Non-NASA CenterNASA Program Space BiologyNASA Discipline Plant BiologyNASA Discipline Number 40-10Plant PhysiologyPlant Shoots/cytology/drug effects/growth & developmentPlant Stems/cytology/drug effects/growth & developmentPlant Growth Regulators/biosynthesisEthylenes/biosynthesisSupport, U.S. Gov't, Non-P.H.SCell DivisionOrganophosphorus Compounds/pharmacologyPlants/cytology/drug effectsSupport, U.S. Gov't, P.H.SCell Wall

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Prasad, T. K., Sack, F. D., Cline, M. G.. 1988-11-01. Effects of shoot inversion on stem structure in Pharbitis nil. https://ntrs.nasa.gov/citations/20040089923

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