Effects of free-air CO[sub 2] enrichment on cotton root morphology

Conference · Sat May 01 00:00:00 EDT 1993 · Plant Physiology; (United States)

OSTI ID:6280062

Prior, S A; Rogers, H H; Runion, G B ^[1]

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1. National Soil dynamics Lab., Auburn, AL (United States)

The response of plants to rising global CO[sub 2] concentration includes its effect on roots. Root morphological changes of cotton grown under two water regimes (wet, 100% of ET replaced and dry, 75% (1990) and 67% (1991) of ET replaced) and two aerial CO[sub 2] concentrations (360 [mu]mol mol[sup [minus]1] and 550 [mu]mol mol[sup [minus]1]) are discussed. A new technique called free-air CO[sub 2] enrichment (FACE). Excavated root systems were partitioned into taproot and lateral roots at vegetative and reproductive growth stages. Laterals were divided into 4 classes (CL) based on diameter size. Taproot variables and total lateral variables at the first sampling showed no water stress effect. At the next sampling, water stress reduced taproot diameter, volume (both years), taproot length and dry weight (in 1991). In most cases FACE increased taproot diameter, volume, dry weight, and tissue density. Likewise, FACE often increased total lateral number, length, volume, dry weight, and tissue density. Extra CO[sub 2] generally increased lateral root number in all classes in 1991, and two classes in 1990 (CL 1 and 2). In 1990, tissue density values were greater (CL 2, 3 and 4), whereas in 1991 no differences were noted. At the first sampling, significant interactions were limited to variables in CL 1 (length, dry weight, and volume) in 1991. Interactions were detected in all CL 3 variables at second sampling 1991. In all cases where interactions were noted, the positive effects of extra CO[sub 2] were found under water stress conditions. At the second sampling in 1991, water stress reduced root length (CL 1 and 2), number (CL 1) and volume (CL 4). The positive effects of elevated CO[sub 2] were most notable in CL 3 laterals. In general, FACE increased tissue density in CL 1,2 characteristics are altered by CO[sub 2] enrichment.

• OSTI ID: 6280062
• Report Number(s): CONF-9307119-; CODEN: PLPHAY
• Journal Information: Plant Physiology; (United States), Vol. 102:1; Conference: 1993 joint annual meeting of the American Society of Plant Physiologists (ASPP) and the Canadian Society of Plant Physiologists (CSPP), Minneapolis, MN (United States), 31 Jul - 4 Aug 1993; ISSN 0032-0889
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
CARBON DIOXIDE
BIOLOGICAL EFFECTS
ECOLOGICAL CONCENTRATION
COTTON
ROOTS
MORPHOLOGICAL CHANGES
PLANTS
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
OXIDES
OXYGEN COMPOUNDS
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