Evaluating Leaf Wax and Bulk Leaf Carbon Isotope Surrogates for Water Use Efficiency and Grain Yield in Winter Wheat Academic Article uri icon

abstract

  • Bulk leaf carbon isotopic composition (13Cbulk) has been widely used to investigate leaf level water use efficiency (WUEl) in efforts to boost grain yield relative to crop water use. Although widely used for isotopic analyses, the bulk leaf represents a complex mixture of compounds. Singlecompound isotopic analyses carry diagnostic advantages over bulk analyses in a range of applications and may also serve as surrogates for WUEl and grain yield in crops. This study tests whether compoundspecific carbon and hydrogen isotopes of leaf wax nalkanes (13Calk and Dalk) and nalcohols (13Calc) could be used as surrogates for WUEl and grain yield using conventional 13Cbulk as a reference. Ten winter wheat (Triticum aestivum L.) cultivars were planted under two irrigation treatments (full and deficit irrigation) at Uvalde (wet location) and Amarillo (dry location), TX, during two growing seasons. There were significant relationships between 13Calk or Dalk and 13Cbulk, indicating they can all serve as surrogates for WUEl in most cases. Compared with 13Cbulk, we found stronger relationships between 13Calk at Uvalde or Dalk under deficit irrigation at Amarillo and grain yield. The 13Calk also had higher broadsense heritability than 13Cbulk, indicating larger cultivar effects in 13Calk than in 13Cbulk. In contrast, the 13Calc was not consistently related with 13Cbulk or grain yield. Our study introduces the idea that 13Calk and Dalk may supplement conventional 13Cbulk with potential to assist in the breeding process when selecting for highWUE and highyielding cultivars.

published proceedings

  • CROP SCIENCE

author list (cited authors)

  • Liu, X., Feakins, S. J., Dong, X., Xue, Q., Han, J., Marek, T., ... Ibrahim, A.

complete list of authors

  • Liu, Xiuwei||Feakins, Sarah J||Dong, Xuejun||Xue, Qingwu||Han, Jie||Marek, Thomas||Leskovar, Daniel I||Neely, Clark B||Ibrahim, Amir MH

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