Expression of Genes Related to Sugar and Amino Acid Transport and Cytokinin Metabolism during Leaf Development and Senescence in L.

Gene editing is becoming the plant breeding tool of choice, but prior to targeting a gene for editing, a knowledge of the gene family members (GFMs) controlling yield is required in the specific crop plant. Critical to yield are components from senescing leaves. We targeted genes controlling senescence in and the release and transport of carbohydrates and amino acids from the source leaves to the pods and seeds. The expression of GFMs for cytokinin biosynthesis () and destruction (), sucrose transporters (), Sugar Will Eventually be Exported Transporters (), amino acid permeases (, and cell wall invertases, was determined using RT-qPCR. GFMs were differentially expressed in leaves of different ages. The expression of many gene family members was lower in the expanding sink leaves compared with the senescing leaves, with the exception of two GFMs and , which were highly expressed. Expression of specific s, s, and s increased in the mature and/or senescing leaves. Expression of s was least in the mature source leaves, but as strong in the senescing leaves as in the young source leaves. was expressed in source and senescing leaves. We discuss the potential impact of the targeted reduction of specific GFMs on source-sink relationships.