HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Bhattacharya, N. C. Articles by strain, B. R. Search for Related Content PubMed Articles by Bhattacharya, N. C. Articles by strain, B. R. Agricola Articles by Bhattacharya, N. C. Articles by strain, B. R.

Growth and Yield Response of Sweet Potato to Atmospheric CO₂ Enrichment¹

Tuber growth of sweet potato (Ipomoea batatas) is a sink that may be limited by source capacity under present ambient CO₂ levels. Hence, sweet potato may demonstrate more response to predicted increases in atmospheric CO₂ than many other annual plants. The present investigation was undertaken to determine the long-term effects of CO₂ enrichment on some physiological parameters, growth, and yield, as well as on the source-sink relationship in sweet potato at different stages of growth. Plants of the cultivar Georgia Jet were grown from stem cuttings in a mixture of gravel and vermiculite in controlled environment chambers at 350, 675, and 1000 µL L^–1 CO₂ and were irrigated with one-half strength Hoagland's solution. The temperature was 28°C during 14-h days and 20°C during 10-h nights. The photosynthetic photon flux density was 550 µmol m^–2 s^–1. The length of main stem, total branch length, number of branches, and leaf area were increased for plants grown at 675 or 1000 µL L^–1 COs. The production of total dry matter of plants increased at each harvest interval in response to CO₂ enrichment but it was greatest in 1000 µL L^–1 CO₂. Specific leaf weight also increased with increased CO₂ concentration. The number and diameter of tubers increased at high CO₂ concentration. At the final harvest, the dry weight of roots and tubers increased 1.8 and 2.6 times in plants grown at 675 and 1000 µL L^–1 CO₂, respectively, compared to those grown at 350 µL L^–1 CO₂. Carbon dioxide enrichment resulted in the modulation of sink capacity to enhance the production of tubers in sweet potato.

Key Words: Growth analysis • Tuber production

² Research associate, professor, Dep. of Plant and Soil Science, Tuskegee Institute, Tuskegee, AL 36088, and research associate, senior research scientist, and professor, Dep. of Botany, Duke Univ., Durham, NC 27706, respectively.

Received for publication August 20, 1984.