PLANT PHYSIOLOGY , Vol 111, Issue 3 721-724, Copyright © 1996 by American Society of Plant Biologists
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WHOLE PLANT, ENVIRONMENTAL, AND STRESS PHYSIOLOGY |
Growth Inhibition in Suspension-Cultured Rice Cells under Phosphate Deprivation Is Mediated through Putrescine Accumulation
C. Y. Shih and C. H. Kao
Department of Agronomy, National Taiwan University, Taipei, Taiwan, Republic of China
The effects of phosphate deprivation on the growth and polyamine levels of
suspension-cultured rice (Oryza sativa) cells were investigated. When rice
suspension cells were deprived of phosphate, cell growth was markedly
inhibited. Phosphate deprivation resulted in a higher putrescine level and
lower spermidine and spermine levels in rice suspension cells. The growth
of rice cells cultured in the absence of phosphate did not recover as a
result of spermidine and spermine addition. D-Arginine and
[alpha]-methylornithine, inhibitors of putrescine biosynthesis, caused a
reduced level of putrescine in rice suspension cells cultured under
phosphate deprivation. The growth of rice cells cultured in the absence of
phosphate was completely recovered after the addition of D-arginine but not
[alpha]-methylornithine. Our results indicate that putrescine accumulation
is a factor causing growth inhibition of suspension-cultured rice cells
under phosphate deprivation.
