Open AccessAutotrophy in Maize Husk Leaves
Author(s) -
Dan Yakir,
Barry Osmond,
Larry Giles
Publication year - 1991
Publication title -
plant physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.554
H-Index - 312
eISSN - 1532-2548
pISSN - 0032-0889
DOI - 10.1104/pp.97.3.1196
Subject(s) - husk , photosynthesis , sucrose , cellulose , botany , heterotroph , chemistry , δ13c , dry matter , autotroph , zea mays , biology , agronomy , food science , stable isotope ratio , biochemistry , bacteria , genetics , physics , quantum mechanics
The natural abundance of carbon and hydrogen isotopic composition, expressed as a delta(13)C value of plant dry matter and cellulose in the hypsophylls (husk leaves) of maize (Zea mays L.) was measured and compared with that of leaves and cobs. The delta(13)C values of outer hypsophylls were usually 2 to 3% per thousand more negative than leaves or other tissues, and became more negative with increasing chlorophyll content, indicating significant local C(3) pathway fixation of CO(2) in the outer hypsophylls. The deltaD values indicated a significant part of hypsophyll cellulose was derived from heterotrophic sources (sucrose from C(4) photosynthesis in other tissues). Isotopic mass balance calculations allowed quantitative estimation of these carbon sources and, in the samples examined, about 16% of hypsophyll cellulose was derived from local C(3) photosynthesis, about 62% from local C(4) photosynthesis, and about 22% from sucrose imported from other leaves.