Chin J Plan Ecolo ›› 2007, Vol. 31 ›› Issue (5): 919-922.DOI: 10.17521/cjpe.2007.0116

• Research Articles • Previous Articles     Next Articles

EFFECTS OF EXOGENOUS ETHYLENE ANDα-NAPHTHALENE ACETIC ACID ON AERENCHYMA FORMATION IN THE STEM OF TWO RIPARIAN PLANT SPECIES ARUNDINELLA ANOMALAAND SALIX VARIEGATAIN THE THREE GORGES RESERVOIR REGION OF CHINA

CHEN Ting; ZENG Bo*; LUO Fang-Li; YE Xiao-Qi; LIU Dian   

  1. Key Laboratory of Eco-environments in Three Gorges Reservoir Region of Ministry of Education, Chongqing Key Laboratory of Plant Ecology and Resources Research in Three Gorges Reservoir Region, School of Life Sciences,Southwest University, Chongqing 400715, China
  • Online:2007-09-30 Published:2007-09-30
  • Contact: ZENG Bo

Abstract:

Aims We investigated aerenchyma formation in stems of riparian plants Arundinella anomala and Salix variegataas affected by addition of ethylene and α-naphthalene acetic acid (α-NAA) under non-flooded conditions in order to as certain whether phytohormone ethylene and auxin are direct stimuli for aerenchyma formation in flooded plants. 
Methods Our experiment included treatments of ethylene (0, 250, 500 mg●L-1), α-NAA (0, 50, 100 mg●L-1) and joint addition of ethylene andα-NAA (250 mg●L-1 + 50 mg●L-1) for A. anomalaand S. variegata plants. Five days following hormone additions, we obtained transverse sections of mid-stems of A. anomala and S. variegata and analyzed aerenchyma formation using E80i Nikon microscope, ACT-2U and Simple PCI software.
Important findings Aerenchyma formation was enhanced when plants were irrigated with either ethylene orα-NAA. Moreover, aerenchyma formation increased with hormone concentration. Aerenchyma formation was enhanced when plants were irrigated with a mixture of ethylene (250 mg●L-1) andα-NAA (50 mg●L-1), but it did not differ from aerenchyma formation induced by either ethylene addition of 250 mg●L-1 or α-NAA addition of 50 mg●L-1. Our work demonstrates that, in flooded environments, the aerenchyma formation in plant stems is directly related to in creases of ethylene and auxin, and flooding may not be the direct stimulus for the formation of aerenchyma.