||Covariate Measurements for Increasing the Precision of Plant Response to O3 and SO2.
Ormrod, D. P. ;
Tingey, D. T. ;
Gumpertz, M. ;
||Corvallis Environmental Research Lab., OR. ;Guelph Univ. (Ontario). Dept. of Horticultural Science. ;Northrop Services Inc., Corvallis, OR.
Sulfur dioxide ;
Air pollution ;
Plant growth ;
Farm crops ;
||Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy.
||Lettuce (Lactuca sativa L. ev. Grand Rapids) and radish (Raphanus sativus L. cv. Cherry Belle) plants growing at baseline environmental conditions were exposed to charcoal-filtered air, 0.40 ppm (v/v) ozone, and 0.80 ppm sulfur dioxide alone or in combination for 6 hours at 14 days from seeding. Analysis of covariance was used to account for significant within-treatment variation in plant growth. Covariates used were: planar leaf area (PLA) at 14 days for leaf area, fresh weight, and dry weight, and dry weight at harvest; plastochron index (PI) at 14 days for PI at harvest; and hypocotyl diameter for hypocotyl weights of radish roots at harvest. The covariates reduced the variability (Standard geometric errors) of the response variables and increased the precision of statistical tests substantially for lettuce but much less for radish. For lettuce, the effect of the gas mixture on plant growth and foliar injury was less severe than that of the single gases. Radish plants, in contrast, exhibited no response to SO2 and the effects of O3 and the mixture on foliar injury and plant growth were similar.
||Prepared in cooperation with Guelph Univ. (Ontario). Dept. of Horticultural Science and Northrop Services, Inc., Corvallis, OR.
||Pub. in HortScience, v18 n6 p896-898 1983.
|NTIS Title Notes
||Reprint: Covariate Measurements for Increasing the Precision of Plant Response to O3 and SO2.
|PUB Date Free Form
||6C; 2D; 57C; 68A; 98D
||Not available NTIS