Interaction of low levels of ozone and relative humidity on leafy vegetables. Final report jun 77-oct 78

Technical Report · Thu Mar 01 04:00:00 EST 1979

OSTI ID:5522579

Bennett, J P

The effects of ozone on the yield of crops are dependent on the conditions of the environment where the crop is grown. Varying levels of humidity are known to affect the development of visible injury produced by ozone but nothing is known about how ozone and humidity affect yield. The purpose of this study was to determine the effects of varying levels of ozone and humidity on the yields of leaf lettuce and spinach. The crops were grown in controlled environment chambers and fumigated six hours daily with 0, 0.08, and 0.18 ppm ozone at 30, 50 and 80% relative humidity (RH) for 32-35 days. Results indicated that spinach yield losses due to ozone were greater at 50% than at 80% RH while lettuce yield losses followed the opposite pattern. This means that generalizations about yield losses in more humid vs. dry environments are not possible because responses are crop specific. Lettuce plants were also significantly smaller and more tender, rendering them unmarketable regardless of the weight loss. This occurred at a concentration below the California one-hour ozone standard of 0.10 ppm and suggests that the standard does not adequately protect this crop.

• Research Organization: California Univ., Davis (USA). Dept. of Vegetable Crops
• OSTI ID: 5522579
• Report Number(s): PB-297062
• Country of Publication: United States
• Language: English

Related Subjects

560303* -- Chemicals Metabolism & Toxicology-- Plants-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AIR POLLUTION
AIR QUALITY
ATMOSPHERES
BIOLOGICAL EFFECTS
CALIFORNIA
CONTROLLED ATMOSPHERES
CROPS
DAMAGE
ENVIRONMENTAL QUALITY
FOOD
HUMIDITY
INJURIES
LETTUCE
LOSSES
NORTH AMERICA
OZONE
POLLUTION
PRODUCTIVITY
SPINACH
STANDARDS
USA
VEGETABLES
WESTERN REGION