Sustainable Irrigation Methods for Alternative Crop Production
The objectives of this study are: 1) assess the effect of sulfuric acid treatment injected through the irrigation system on soil pH and blueberry growth and development; 2) evaluate the effect of plug-in emitter and micro-jet irrigation systems on soil pH and blueberry performance; 3) determine the effect of various mulch treatments on soil organic matter content and blueberry plant growth.
Two on-farm experimental plots were selected in 2008 to apply a set of soil organic amendments and various irrigation systems. Soil amendments consisted of various rates of pine bark and peanut hulls, applied at 134 yd3, 269 yd3, and 403 yd3 of organic matter per acre respectively. The experimental plots were replicated three times, and planted to ‘Climax’. Irrigation treatments consisted of: Client-installed drip tape (control); Micro-Jet Spray emitters; and Plug-in drip emitters. In all treatments a timer was installed with soil moisture feedback for irrigation scheduling. The irrigation treatment plots consisted of seven replications and were applied on Austin and Climax blueberry cultivars.
Soil samples and leaf tissue samples were collected throughout the growing season to determine treatment effect on soil pH and organic matter, as well as on soil and plant macro- and micronutrients.
Our results suggested that pine bark treatment applied at a rate of 269 yd3 provided the largest leaf area and the greatest plant growth of Climax blueberry, when compared to other mulch rates tested. No differences were found on Climax or Austin cultivars leaf chlorophyll content due to the irrigation treatment applied. However, a high percentage of Austin blueberry plant decline was evident in the experimental plot. We found out that a new disease named bacterial leaf scorch, to date considered a problem of southern highbush blueberry varieties was partially accountable for Austin rabbiteye blueberry decline.
Impacts and Contributions/Outcomes
A blueberry production workshop was co-hosted by the project leaders and farmer-cooperators on October 21, 2008. An overview of the results generated during the first year of our investigation was presented to blueberry growers in the Wiregrass region of Alabama.
This ongoing study is designed to facilitate developing alternative crops that help a producer’s operation to become more economically sustainable and investigates practices and systems that increase the viability of an existing farming practice. Other substantial contribution of this research will be promotion of low-volume systems that can apply precise and uniform water volumes while conserving natural resources, and make the most efficient use of on-farm resources. The integration of natural biological cycles will contribute to improving soil mycorrhizal infection and soil physical properties.