01945naa a2200241 a 450000100080000000500110000800800410001902200140006002400420007410000200011624501710013626000090030752011650031665300230148165300290150465300170153370000200155070000170157070000170158770000140160470000220161877300630164020132732015-04-16       2014    bl uuuu     u00u1 u    #d  a1807-86217 a10.4025/actasciagron.v36i3.179862DOI1 aBRITO, G. G. de  aLeaf-level carbon isotope discrimination and its relationship with yield components as a tool for cotton phenotyping in unfavorable conditions.h[electronic resource]  c2014  aThe initial goal of this study was to measure the efficiency of carbon isotope discrimination (?) in distinguishing between cotton plant genotypes subjected to two water regimes. In addition, ? measurements, leaf water potential and gas exchange ratios were monitored. Using Brazilian breeding lines, this study also tested the usability of ? as a proxy for selecting high-performing yield components in cotton plants grown in unfavorable conditions, particularly water deficiency. For these experiments, ? and yield components were measured and their correlations analyzed. Differences among cotton genotypes for ? (p &lt 0.0001) were verified, and it was found that this variable was significantly correlated with gas exchange. There was a significant positive correlation between ? and seed cotton yield only in the site experiencing severe water deficiency (Santa Helena de Goiás). However, ? had a significant negative correlation with fiber percentage. Our results indicate that ? is a suitable tool for cotton phenotyping, and it may be applied in cotton breeding programs that aim to produce high-performing yield components in unfavorable conditions.  aEstresse abiótico  aFracionamento do carbono  aTroca gasosa1 aSUASSUNA, N. D.1 aSILVA, V. N.1 aSOFIATTI, V.1 aDIOLA, V.1 aMORELLO, C. de L.  tActa Scientiarumgv. 36, n. 3, p. 335-345, jul./set. 2014.