Studies on conidial germination and factors affecting disease development of Stemphylium blight of onion
153 / 141
Keywords:
Allium cepa, conidial germination, host surface, inoculum concentrations, nutrient solutions, Stemphylium blight, Stemphylium vesicariumAbstract
A conidial suspension of S. vesicarium prepared from a 10 d-old culture had a lag period of at least 2 h for germination on the leaf surface of onion (Allium cepa) cv. Hisar-2. After 32 hours, 76% of the conidia had germinated. In different solutions, the max. av. conidial germination (63.30%) was recorded in dew drops followed by glucose solution (55.50%), tap water (46.60%) and distilled water (33.10%). There was a steep increase in conidial germination in all solutions, and on plant foliage, after 8 h of incubation and thereafter, it gradually increased up to 32 h of incubation. Disease intensity increased with increase in inoculum concn (5000 conidia/ml) but declined when inoculum concn was further increased (10 000 conidia/ml). However, this decline was not statistically significant. Max. disease intensity was recorded when 90-120 d-old plants were inoculated with 21 d-old cultures. The infectivity of cultures increased up to 21 days but declined after 30 days. Plants of all ages (10-120 d) were almost equally susceptible. The fungus required at least 16 h in a saturated atmosphere for initiation of disease.
Downloads
Issue
Section
License
For Authors
As soon as an article is accepted for publication, authors are requested to assign copyright of the article (or to grant exclusive publication and dissemination rights) to the publisher (Indian Phytopathlogical Society). This will ensure the widest possible protection and dissemination of information.
For Readers
While the advice and information in this journal is believed to be true and accurate at the date of its publication, the authors, the editors, nor the publisher can accept any legal responsibility for any errors or omissions that may have been made. The publisher makes no warranty, express or implied, with respect to the material contained herein.
All articles published in this journal are protected by copyright, which covers the exclusive rights to reproduce and distribute the article (e.g., as offprints), as well as all translation rights. No material published in this journal may be reproduced photographically or stored on microfilm, in electronic data bases, on video disks, etc., without first obtaining written permission from the publisher. The use of general descriptive names, trade names, trademarks, etc. in this publication, even if not specifically identified, implies that these names are protected by the relevant laws and regulations.