Temperature response of root‐lesion nematode (Pratylenchus thornei) reproduction on wheat cultivars has implications for resistance screening and wheat production. (12th January 2015)

• Record Type: Journal Article
• Authors: Thompson, J.P.; Clewett, T.G.; O'Reilly, M.M.
• Is Part Of: Annals of applied biology. Volume 167:Number 1(2015)
• Page Start: 1
• Page End: 10
• Publication Date: 2015-01-12
• Subjects: Crop science -- Periodicals; Plants, Protection of -- Periodicals; Crops -- Ecology -- Periodicals; 630
• DOI: 10.1111/aab.12187
• Languages: English
• ISSNs: 0003-4746

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <p>The root‐lesion nematode <italic>Pratylenchus thornei</italic> is a major pathogen of wheat and other field crops, particularly in the northern grain region of sub‐tropical eastern Australia. Research was conducted into the temperature requirements of <italic>P. thornei</italic> for reproduction on wheat to increase the reliability of selection in resistance tests for wheat breeding. Final population densities (<italic>P</italic><sub>f</sub>) of <italic>P. thornei</italic> were determined on four wheat cultivars (Gatcher, GS50a, Potam and Suneca) at fortnightly intervals from 8 to 18 weeks at a range of six soil temperatures (15°C, 20°C, 22.5°C, 25°C, 27.5°C and 30°C) in a glasshouse experiment. <italic>Pratylenchus thornei</italic> had the highest <italic>P</italic><sub>f</sub> in the temperature range of 20–25°C on all wheat cultivars at all growth times after sowing, with no nematode reproduction measured at 30°C and very little at 15°C. The wheat cv. GS50a consistently produced lower <italic>P</italic><sub>f</sub> than cvs Gatcher, Potam and Suneca in the optimum temperature range of 20–25°C. In carrot disc cultures, <italic>P. thornei</italic> had an optimum temperature of 25°C with little reproduction at 17.5°C and none detectable at 30°C. A standard soil temperature of 23°C was chosen to maximise differences in nematode reproduction between resistant and susceptible wheat genotypes for selection in wheat breeding, and to improve reproducibility among successive experiments. The relationships derived from these experiments will be valuable for simulation of <italic>P. thornei</italic> reproduction in crop growth models. They also indicate that early sowing of wheat into cool soil (≤15°C) in farmers' fields of the northern grain region should favour wheat growth over nematode reproduction and increase grain yield.</p> </abstract>