TITLE:
High Temperature and the Ethylene Antagonist 1-Methylcyclopropene Alter Ethylene Evolution Patterns, Antioxidant Responses, and Boll Growth in Gossypium hirsutum
AUTHORS:
Eduardo M. Kawakami, Derrick M. Oosterhuis, John L. Snider, Toby R. FitzSimons
KEYWORDS:
Ethylene; Glutathione Reductase; Gossypium hirsutum; High Temperature; 1-Methylcyclopropene
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.4 No.7,
July
5,
2013
ABSTRACT:
The cotton (Gossypium hirsutum L.) crop experiences
high temperatures during flowering and boll development, but information regarding
the impact of ethylene inhibition and high temperature on early boll
development is limited. The objective of this study was to determine the
effects of high temperature and the anti-ethylene compound 1-methylcy-cloprone (1-MCP) on G. hirsutum boll development. Treatments
consisted of temperature regime (38/20?C and 30/ 20?C), 1-MCP
treatment, and days past anthesis (DPA). High temperature decreased ethylene
synthesis by 61% at 2 DPA, and 1-MCP caused a 40% decrease in ethylene
production at 1 DPA. Glutathione reductase activity increased under high
temperature, whereas superoxide dismutase activity (SOD) and membrane
peroxidation (malondialdehyde content) remained unchanged. 1-MCP treatment did
not affect GR activity in developing bolls. High temperature and 1-MCP
treatment increased the weight of cotton bolls collected 8 DPA with an increase
of 0.7 and 1 g, respectively. We
propose that increased GR activity in bolls exposed to high temperature may
mitigate oxidative damage. Additionally, we conclude that ethylene inhibition
(either high temperature or 1-MCP-induced) immediately after flowering (1 or 2
DPA) could potentially have positive impacts on early boll growth.