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See more from this Division: SSSA Division: Soil Physics and Hydrology
See more from this Session: Soil Physics and Hydrology: Honoring the Contributions of Bob Luxmoore, John Letey, and John Hanks: I

Tuesday, November 17, 2015: 10:00 AM
Minneapolis Convention Center, 101 DE

ABSTRACT WITHDRAWN

Abstract:
Avocado is an orchard crop that requires careful irrigation management due to its extreme sensitivity to salinity and chloride toxicity. In other plants, root hypoxia caused by over irrigation has been shown to lead to increased levels of chloride in plant leaf tissue. Lack of soil oxygen by over irrigation also has been shown to contribute to stomatal closure, reduced root growth, reduced photosynthesis, and reduction of macronutrients due to reduction of Mycorrhizae formation. These effects are greatly increased in soils with high bulk density, low organic matter, heavy clay texture, and poor infiltration such as the soils found in California, where 90% of US avocado production is located. Here we report the results of a three year field study that examined relationships between soil physical properties and specific ion uptake with a focus on soil aeration and chloride accumulation in avocado leaf tissues.  Data were collected from 7 different orchards across a transect of the avocado production area in California for trees on the four most commonly used commercial rootstocks. Each location was installed with in-situ soil monitoring equipment to record soil air volume, soil salinity, soil temperature, soil water potential and irrigation frequency. Leaf tissue was collected each year to determine nutrient data. Number of hypoxia events, frequency and cumulative hours of hypoxia were used in a regression models to determine statically relevant relationships and leaf tissue chloride. Each rootstock was evaluated individually to determine rootstock effects on ion uptake as well as overall trends in all rootstocks. Results of this research emphasize the need for careful irrigation management in avocado production to avoid root hypoxia and effectively manage chloride toxicity when using saline water supplies for irrigation.

See more from this Division: SSSA Division: Soil Physics and Hydrology
See more from this Session: Soil Physics and Hydrology: Honoring the Contributions of Bob Luxmoore, John Letey, and John Hanks: I