'Spikelet stop' determines the maximum yield potential stage in barley. (22nd July 2021)

• Record Type: Journal Article
• Authors: Thirulogachandar, Venkatasubbu; Schnurbusch, Thorsten
• Editors: Rebetzke, Greg
• Is Part Of: Journal of experimental botany. Volume 72:Number 22(2021)
• Page Start: 7743
• Page End: 7753
• Publication Date: 2021-07-22
• Subjects: Barley -- grain yield -- inflorescence meristem -- maximum yield potential -- spikelet initiation -- spikelet growth; Botany -- Periodicals; Botany, Experimental -- Periodicals; Plant physiology -- Periodicals; 580
• DOI: 10.1093/jxb/erab342
• Languages: English
• ISSNs: 0022-0957

Abstract

Abstract : The barley maximum yield potential (MYP) stage can differ from the awn primordium stage and varies depending on the genotype and growth conditions. We suggest key steps to identify MYP in barley that might apply to related cereals. Abstract: Determining the grain yield potential contributed by grain number is a step towards advancing the yield of cereal crops. To achieve this aim, it is pivotal to recognize the maximum yield potential (MYP) of the crop. In barley ( Hordeum vulgare L.), the MYP is defined as the maximum spikelet primordia number of a spike. Many barley studies assumed the awn primordium (AP) stage to be the MYP stage regardless of genotypes and growth conditions. From our spikelet-tracking experiments using the two-rowed cultivar Bowman, we found that the MYP stage can be different from the AP stage. Importantly, we find that the occurrence of inflorescence meristem deformation and its loss of activity coincided with the MYP stage, indicating the end of further spikelet initiation. Thus, we recommend validating the barley MYP stage with the shape of the inflorescence meristem and propose this approach (named 'spikelet stop') for MYP staging. To clarify the relevance of AP and MYP stages, we compared the MYP stage and the MYP in 27 barley accessions (two- and six-rowed accessions) grown in the greenhouse and in the field. Our results reveal that the MYP stage can be reached at various developmental stages, which greatly depend on the genotype and growth conditions. Furthermore, we propose that the MYP stage and the time to reach the MYP stage can be used to determine yield potential in barley. Based on our findings, we suggest key steps for the identification of the MYP stage in barley that may also be applied in a related crop such as wheat.