Abstract Detail

Host/Plant Pathogen Interactions and Plant Health Management

Thangam, Nimllash [1].

Evaluation of optimum temperature and moisture requirements for Ascochyta pisi and Didymella pinodes. NT SIVACHANDRA KUMAR, S BANNIZA, Crop Development Centre/Department of Plant Sciences, University of Saskatchew.

Ascochyta blight is one of the major diseases of field pea in Saskatchewan. This disease is caused by a complex of four pathogens that include Didymella pinodes, Ascochyta pisi, Phoma medicaginis var. pinodella and Phoma koolunga. Didymella pinodes is the most common pathogen on the prairies, but for the past 10 years A. pisi has been recovered at higher levels than D. pinodes from peas harvested in south and south-western cropping areas of Saskatchewan. Conidial germination of A. pisi and D. pinodes on glass slides, and disease severity caused by both pathogens on inoculated plants were assessed at temperature of 10–30ËšC and with wetness periods of 0-12h to determine their respective temperature and wetness optimum. A Split Plot Design with four replications was used, where temperatures were considered the main plot treatments and incubation times were subplot treatments, which were considered repeated measures. All germination tests were carried out with conidial suspension on well slides, which were placed on top of moist filter paper in a labeled Petri dish. Sixteen days old pea seedlings cv. Cooper with susceptibility to A. pisi infection was used in the whole plant experiment. Assessment of disease severity was carried out 7 and 14 days after inoculation using a 0-10 scale. Data were analyzed using the mixed model procedure of the SAS program, considering temperature and incubation time fixed effects, whereas blocks and block * temperature were considered random effects. Differences in temperature and moisture optima between the two pathogens may explain why A. pisi has been observed more frequently in southern and south-western parts of Saskatchewan.
Presenter: Nimllash Thangam
Mail id: nis286@mail.usask.ca

1 - University of Saskatchewan, Plant Science, Room 4D36, Agriculture Building
, 51 Campus Drive, Saskatoon, SK, S7N 5A8


Keywords:
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Presentation Type: Oral Paper:Papers for Topics
Session: 65
Location: Salon 9/The Shaw Conference Centre
Date: Wednesday, July 29th, 2015
Time: 10:45 AM
Number: 65003
Abstract ID:707
Candidate for Awards:None