Fine tuning the shoot and inflorescence architectures for improved tomato yield

In this project, we are determining the contribution of different types of variations, in gene function and in gene regulation, to altered shoot architecture first, and to field performance in the next stage. We are using tomato as a target, but also as a model for many other crops. Our focus is on two different components of yield associated traits - shoot architecture and organization of the inflorescence. Our focus was on two types of regulators; 1) genes involved in florigen - antiflogen balance and the way they impact the shoot, and 2) genes involved in inflorescence branching and it this way, the way they impact the number of flowers produced by the plant. For the first class, we described our thoughts on that matter in a joint review (Eshed and Lippman, 2019) where we argued that annualization of short-lived vine plants such as tomato and soybean was their major adaptation for intensive modern farming. This annualization was achieved by introduction of mutations in the anti florigen gene SELFPRUNING, mutations that were also used to domesticate/adapt cotton, roses, strawberries and more (Eshed and Lippman, 2019). Indeed, introduction of this mutation and additional one in another antifloraigen gene SP5G into a vine type tomatoes resulted in compact, early yielding plants suitable for urban agriculture (Kwon et al., 2020 - please note that Yossi Capua, a former graduate student from the Eshed group is a coauthor of this study). The other side of this project, customized generation of large branched inflorescences, relied on ongoing collaboration between the two labs on genes like S and genes of the SEP clade, J2 and EJ2. We first showed that highly branched j2 ej2 inflorescences can be quantitatively modified by introduction of either null or naturally weak alleles of the TM3/STM3 gene cluster (Alonge et al., 2020). We next showed that variation in inflorescence branching can be obtained by customized interreference in selected promoter motifs of S, a gene that is otherwise essential at the seed stage (Hendelamn et al., 2021). Overall, our joint project provided some prime examples for targeted use of genome editing for the formation of valuable alleles that can either improve modern crops or, significantly, open the door for rapid "domestication" of orphan crops