Antagonistic effect of polyamines on ABA-induced suppression of mitosis in Allium cepa L.

作者：Mahajan Arpana; Sharma Shashi^*

来源：Indian Journal of Experimental Biology, 2009, 47(2): 136-139.

• ABA
• Allium cepa
• Catalase
• Mitotic Index
• Putrescine
• Spermidine
• Spermine

Effect of abscisic acid (ABA) and polyamines (PAs) [putrescine (Put), spermidine (Spd) and spermine (Spm)] on mitosis in root tips of A. cepa was studied. Treatment with ABA (0.1 to 100 mu M) for 24 hr suppressed the mitosis, measured as mitotic index (MI), in a concentration-dependent manner with approx. 50% suppression at 10 mu M of ABA. Treatment with different PAs (I to 100 mu M) had differential mitosis suppression effect. Spin was most inhibitory followed by Spd and Put, respectively. The higher concentrations of PAs (I mM Put; 0.1 and 1mM Spd or Spin) caused cell distortion. Remarkably, a 24 hr pretreatment of root tips with PAs prior to ABA (100 mu M) treatment resulted in a general concentration-dependent reversal of ABA-induced suppression of MI. Catalase (CAT) activity in the root tips, an indicator of redox metabolism, increased due to ABA treatment in a concentration-dependent manner, remained unaltered in response to Put and declined due to Spd and Spm (>= 0.1 mM). However, all PAs, irrespective of their individual effects, generally antagonized the ABA-dependent increase in CAT activity. Data indicate the possibility of ABA-PA interaction in the regulation of mitosis.

• 出版日期2009-2