2511:
Genetic Determination for Susceptibility to CO2-Induced Injury In Apple

Sunday, July 26, 2009: 10:45 AM
Jefferson A (Millennium Hotel St. Louis)
Nnadozie Oraguzie , Washington State University, Prosser, WA
Doug Burmeister, PhD , Mt Albert Research Research Center, Plant & Food Research New Zealand Limited, Auckland, New Zealand
Peter Alspach , Riwaka Research Center, Plant & Food Research New Zealand Limited, Motueka, New Zealand
Nagin Lallu , Mt Albert Research Center, Plant & Food Research New Zealand Limited, Auckland, New Zealand
Use of CA storage is common in horticulture for extending the shelf life and quality attributes of fruits. However, maintaining CO2 at levels low enough to avoid CO2 injury is a major problem in the operation of CA facilities. This study was aimed at determining genetic basis for susceptibility to CO2 injury in apple to facilitate 1) parental selection and development of new varieties with little or no susceptibility to CO2 injury, and 2) setting up further genetic studies to dissect the underlying genetic mechanisms involved. We carried out studies in 2001 and 2002 with 41 and 35 seedling families respectively, selected from ‘breeding population 94’ of an apple recurrent selection programme well suited for genetic studies. Fruit from these families were harvested at or near physiological maturity and subjected to 3 CA treatments; air, 5% CO2 (+ balanced air) and 10% CO2 (+ balanced air) for 10 weeks in 2001 or 6 weeks in air and at 5% CO2 in 2002. The incidence and severity of CO2 injury were assessed after storage and various statistical procedures including GLM, ANOVA, permutation tests, Monte Carlo simulations and Bootstrapping were used to explore the sources of variation for incidence of CO2 injury. There was a significant family or genetic effect (p<0.001) on susceptibility to CO2 injury. The results provide the basis for further studies to identify the underlying genetic mechanisms involved as well as selection of parents to develop new varieties with little or no susceptibility to CO2 induced injury.