Sustainable Irrigation Methods for Alternative Crop Production

Project Overview

OS08-040
Project Type: On-Farm Research
Funds awarded in 2008: $15,000.00
Projected End Date: 12/31/2010
Region: Southern
State: Alabama
Principal Investigator:
Dr. Elina Coneva
Auburn University

Annual Reports

Information Products

Commodities

  • Fruits: berries (blueberries)

Practices

  • Crop Production: irrigation, organic fertilizers
  • Education and Training: demonstration, on-farm/ranch research, workshop
  • Pest Management: cultivation
  • Soil Management: green manures, soil quality/health
  • Sustainable Communities: sustainability measures

    Abstract:

    Recent changes in commodity programs and competition from imported commodities have increased the income risk to farmers. As a result, many farmers are considering a transition to an alternative, high-value crop production as a way to sustain their income. One crop of significant interest is rabbiteye blueberry. Recent demand for this fruit has increased dramatically and so have prices received for the product by producers. Over 270 acres of blueberries have been planted in southeastern Alabama in the past three years. Sites selected for blueberry establishment generally followed row crops land, where soils were marginally suited for blueberry production, featuring low soil organic matter content, and high soil pH. Supplemental irrigation water sources in the southeastern part of the state are carbonate aquifers. In events where the supplemental irrigation is the predominant water source, particularly in drought years, alkaline irrigation water will create alkaline soil conditions that will not favor successful blueberry establishment and production. The purpose of this on-farm study was to generate an enhanced knowledge of the benefits of using different approaches to improve the soil organic matter content, to correct soil pH, and to manage irrigation water alkalinity for sustainable blueberry production.

    Introduction

    Irrigation is a determinant factor in the growth and production of blueberry, mainly because the plant root system is superficial and confined, which restricts the water uptake capacity. Furthermore, blueberry plants are especially sensitive to irrigation water quality. Alkaline irrigation water will eventually raise the soil pH to a level harmful to blueberries. Acid injection through the irrigation system is required to lower pH to an acceptable level and to promote blueberry plant establishment and development.
    The most common irrigation systems used to irrigate blueberries are micro-jet and drip. Previous studies demonstrated that during the first 2 years of harvest, plants under drip irrigation produced higher yields compared to those with the microjet system, whereas in the fourth and subsequent season micro-jet system surpassed drip irrigation. The objectives of our study were to assess the feasibility of acid injection through the irrigation system in combination with micro-jet or drip system on the establishment and development of selected rabbiteye blueberry cultivars.
    Another method to buffer soil pH changes, increase the soil organic matter and help retain water in the root zone is adding soil amendments such as peat moss and mulch that promote root development, and maintain high soil water content with a good level of aeration in the soil. Thus, another objective of our study was to evaluate the effect of three mulching treatments on blueberry growth and development.

    Project objectives:

    The main objectives of our study were to:
    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 different rates of pine bark and peanut hull treatments on soil organic matter content and blueberry establishment and plant growth.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.