Evaluating Leaf Wax and Bulk Leaf Carbon Isotope Surrogates for Water Use Efficiency and Grain Yield in Winter Wheat. Issue 2 (1st March 2019)

• Record Type: Journal Article
• Authors: Liu, Xiuwei; Feakins, Sarah J.; Dong, Xuejun; Xue, Qingwu; Han, Jie; Marek, Thomas; Leskovar, Daniel I.; Neely, Clark B.; Ibrahim, Amir M. H.
• Is Part Of: Crop science. Volume 59:Issue 2(2019)
• Page Start: 718
• Page End: 732
• Publication Date: 2019-03-01
• Subjects: Crop science -- Periodicals; Cultures -- Périodiques; Cultures de plein champ -- Périodiques; Crop science; Nutzpflanzen; Zeitschrift; Pflanzenbau; Periodicals; 633
• DOI: 10.2135/cropsci2018.07.0452
• Languages: English
• ISSNs: 0011-183X

Abstract

Abstract : Bulk leaf carbon isotopic composition (δ 13 Cbulk ) 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. Single‐compound 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 compound‐specific carbon and hydrogen isotopes of leaf wax n ‐alkanes (δ 13 Calk and δDalk ) and n ‐alcohols (δ 13 Calc ) could be used as surrogates for WUEl and grain yield using conventional δ 13 Cbulk 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 δ 13 Calk or δDalk and δ 13 Cbulk, indicating they can all serve as surrogates for WUEl in most cases. Compared with δ 13 Cbulk, we found stronger relationships between δ 13 Calk at Uvalde or δDalk under deficit irrigation at Amarillo and grain yield. The δ 13 Calk also had higher broad‐sense heritability than δ 13 Cbulk, indicating larger cultivar effects in δ 13 Calk than in δ 13 Cbulk . In contrast, the δ 13 Calc was not consistently related with δ 13 Cbulk or grain yield. Our study introduces the idea that δ 13 Calk and δDalk may supplement conventional δ 13 Cbulk with potential to assist in the breeding process when selecting for high‐WUE and high‐yielding cultivars.