Ozone and Botrytis interactions in onion-leaf dieback: open-top chamber studies

Journal Article · Thu Sep 01 00:00:00 EDT 1977 · Phytopathology; (United States)

DOI:https://doi.org/10.1094/Phyto-67-1080· OSTI ID:5662490

Wukasch, R T; Hofstra, G

Paired open-top chambers were used to study interactions between Botrytis spp. and ozone in field-grown onions. Charcoal filters removed 35 to 65% of the ambient ozone, resulting in six-fold reduction of onion leaf dieback and a 28% increase in onion yield compared with unfiltered chambers. Symptoms of leaf injury appeared soon after ozone levels exceeded 294 ..mu..g/m/sup 3/ (0.15 ppm) for 4 hr. Lesions caused by Botrytis were few because no dew formed in the chambers. However, when leaves were wetted with foggers, inoculation with mycelial suspensions of B. sauamosa in late August produced significantly more lesions and leaf dieback in the unfiltered chamber. Botrytis squamosa, B. cinerea, B. allii, and several genera of secondary fungi were isolated from these lesions. Botrytis squamosa was recovered from lesions only, whereas B. cinerea and B. allii were associated more generally with onion leaf tissue regardless of lesions. 25 references, 1 figure, 2 tables.

• Research Organization: Univ. of Guelph, Ontario
• OSTI ID: 5662490
• Journal Information: Phytopathology; (United States), Vol. 67
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
FUNGI
SYNERGISM
ONIONS
INJURIES
PLANT DISEASES
OZONE
BIOLOGICAL EFFECTS
COMPARATIVE EVALUATIONS
LEAVES
PRODUCTIVITY
STIMULATION
SYMPTOMS
FOOD
PLANTS
VEGETABLES
560303* - Chemicals Metabolism & Toxicology- Plants- (-1987)