Location: Sugarcane Field StationTitle: Sugarcane growth and physiological responses to soil salinity
|GAO, XINXIN - Yunnan Sugarcane Research Institute|
Submitted to: American Society of Sugar Cane Technologists
Publication Type: Abstract Only
Publication Acceptance Date: 4/30/2018
Publication Date: 9/6/2018
Citation: Zhao, D., Gao, X., Aria, P.J. 2018. Sugarcane growth and physiological responses to soil salinity. American Society of Sugar Cane Technologists. 38:62.
Interpretive Summary: N/A
Technical Abstract: A pot study was conducted at the USDA-ARS Sugarcane Field Station, Canal Point, Florida to investigate effects of soil salinity on plant growth, leaf photosynthesis, and other physiological traits of two sugarcane cultivars (CP 96-1252 and CP 00-1101) and an Erianthus during early growth stage (50 to 150 days after planting) using five soil salt concentrations (0 [Control], 38, 75, 150, and 300 mM of NaCl added). Plant growth (tillers, plant height and nodes on the primary stem), leaf photosynthetic characters (photosynthetic rate, stomatal conductance, intercellular CO2 concentration, and transpiration rate), and leaf water soluble sugar (glucose, fructose, sucrose) concentrations were determined during the experiment. Results indicated that effects of salinity on growth, carbon fixation, and photoassimilate translocation depended on the salt concentration. Among the three growth traits measured, plant height was the most sensitive while the number of nodes was the most tolerant to salt concentration. Leaf photosynthetic rates (Pn) of the 38 and 75 mM salt treatments did not differ from that of the control, but the 150 and 300 mM salt treatments had 16 and 39% lower Pn, respectively, than the control. The low leaf Pn due to salinity was associated with decreases in not only stomatal conductance but also the carbon fixation enzyme activities. Additionally, the results of leaf sugar composition and concentrations in early morning and late afternoon indicated that high salt concentration depressed photoassimilate translocation from leaves to other tissues. These findings can improve our knowledge in better understanding of physiological mechanisms of salinity influence on sugarcane growth and yields.