In:
Journal of Environmental Quality, Wiley, Vol. 17, No. 4 ( 1988-10), p. 635-643
Abstract:
Recent field research has shown that ambient concentrations of ozone (O 3 ) have the potential to reduce yield of a number of economically important crop species. Soil water levels have been shown sometimes to modify the extent of the reduction. The primary emphasis of most of these studies has been on the plant component that represents economic yield. Less emphasis has been placed on characterization of the effects of O 3 on growth of the total plant that ultimately determines yield. In this study, we measured season‐long growth of field‐grown cotton ( Gossypium hirsutum L. ‘McNair‐235’) that was exposed to a range of O 3 concentrations at two levels of soil moisture, well‐watered (WW) and water‐stressed (WS). The cotton was exposed for 12 h d −1 throughout the growing season in open‐top chambers to five O 3 concentrations that ranged from 0.020 to 0.074 µ L L −1 (seasonal mean 12 h d −1 concentration). Three cotton plants were sampled from each chamber at 2‐ to 3‐ wk intervals during the season, and biomass and growth measurements were made on all major plant parts. Ozone stress reduced leaf and root biomass in particular, while stem tissues were less affected. Partitioning of biomass among plant tissues was affected by O 3 at certain times during the season. Leaf area duration (LAD) was reduced by O 3 in both WW and WS treatments, but changes in the yield/LAD ratio and net assimilation rate indicated that reduced efficiency of leaves also was responsible for yield reductions in the WW plots. Water stress caused fewer significant effects overall than did O 3 , although it appeared to reduce the growth of most plant parts, especially at low O 3 concentrations. There were no significant O 3 × water interactions for the growth variables measured.
Type of Medium:
Online Resource
ISSN:
0047-2425
,
1537-2537
DOI:
10.2134/jeq1988.00472425001700040020x
Language:
English
Publisher:
Wiley
Publication Date:
1988
detail.hit.zdb_id:
120525-0
detail.hit.zdb_id:
2050469-X
