Volume 9, Issue 2 (summer 2005)                   JWSS 2005, 9(2): 159-169 | Back to browse issues page

XML Persian Abstract Print


Download citation:
BibTeX | RIS | EndNote | Medlars | ProCite | Reference Manager | RefWorks
Send citation to:

A. Davoodee, E. Majidi, H. Rahimian, M. Valizadeh. Study of Fire Blight Severity in Some Pear Cultivars with USDA Standard System. JWSS. 2005; 9 (2) :159-169
URL: http://jstnar.iut.ac.ir/article-1-350-en.html
Abstract:   (17573 Views)
The fire blight with the bacterial causal agent, Erwinia amylovora (Burrill) winslow etal. is one of the most important diseases of the pome fruits that causes the economical losses to quince, pear and apple productions, respectively, in some parts of country. To determine the infection severity of the 43 raturally infected pear cultivars in collection of karaj horticulture research division and also for studing the reaction of these cultivars against disease, the evaluation was performed by the USDA standard system for these cultivars in collection. In this study, although the most of cultivars had been infected on the natural conditions, but disease severity was significantly different between them. By the USDA system, pear cultivars were divided in the 2 classes. Percentage of pear cultivars in very susceptible and moderately susceptible classes were 81.4 and 18.6 respectively. Also for dividing the pear cultivars, beside of USDA method, SPSS software and the cluster analysis were also by the UPGMA method and cultivars were divided into 3 clusters, but it seems that the classification of cluster analysis did not conform with USDA system. Correlation of I.V.S in the artificial tests and the disease severity by natural infection was very significant (r= -0.83).
Full-Text [PDF 266 kb]   (2452 Downloads)    
Type of Study: Research | Subject: Ggeneral
Received: 2008/01/9 | Published: 2005/07/15

Add your comments about this article : Your username or Email:
CAPTCHA

Rights and permissions
Creative Commons License This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

© 2021 CC BY-NC 4.0 | JWSS - Isfahan University of Technology

Designed & Developed by : Yektaweb