THE EFFECTS OF ETHYLENE ON GROWTH, WATER USE EFFICIENCY AND YIELD OF CORN GROWN UNDER DIFFERENT LEVELS OF IRRIGATION AND WATER DEFICIT
Water Management Research
2013 Annual Report
1a.Objectives (from AD-416):
To determine the response of corn to endogenous ethylene produced during specific growth stages during water stress.
1b.Approach (from AD-416):
1. Plot size: 6 rows by 10 m, with two row buffers between plots
a. Replicated 8 times
2. Corn Variety: Dekalb 5259 triple stack
3. Irrigation Levels
b. 100% ET until the V6-V7 growth stage
1). Withhold water until leaves begin to curl in the middle of the day.
2) Apply 25 g/ha of 1-MCP
3) Remain under water stress for 7-10 d after application
4) 100% ET for the rest of the season.
4. 1-MCP application rate: 25 g a.i./ha applied in 200 l/ha with appropriate surfactant as designated by cooperator.
a. Plant height (internode length) (early application timing only)
b. Leaf elongation (hand measures of leaf length and width and/or NDVI)
c. Transpiration (Porometry)
d. Gas exchange (CO2 and H2O) every day after application and 3 weeks after drought is relieved.
e. Rate of senescence (SPAD of leaf above ear leaf and leaf below ear leaf– regular intervals; or canopy level multispectral analysis)
f. Yield of middle 2 rows of each plot
g. Yield components (kernel #/ear; 1000 kernel wt. test weight, etc.).
This project was completed in 2013 and a final report submitted to AgroFresh. In the final year we applied 1-MCP (25 g/ha) to corn in the V-10 growth stage when it began to show leaf curling in the middle of the day. A time-lapse camera was set up to monitor leaf curling during the day for 10 days following the application of 1-MCP and yield was taken at the end of the growing season. There was no apparent plant response to the application of 1-MCP and there was no difference in yield between the treated and untreated plots. This study concluded a multi-year project on the potential for 1-MCP to mitigate the drought response in corn. Unfortunately no positive responses on yield were ever documented.