The branched spike phenotype is an important supernumerary spikelet trait of Triticum turgidum L. associated with the production of significantly more grains per spike, thereby offering a higher potential yield. However, the genetic basis of branch meristem (BM) development remains to be fully elucidated in wheat. TAW1, an ALOG (Arabidopsis LSH1 and Oryza G1) family gene, has been shown to function as a unique regulator in promoting BM development in rice. In this study, we found that the development pattern of the BMs of the branched spike in wheat was similar to the indeterminate BMs of rice. Moreover, phylogenetic analysis classified the ALOG genes into 12 groups. This family of genes was found to have evolved independently in eudicots and monocots and was evolutionarily conserved between wheat and rice as well as during wheat polyploidization. Furthermore, experiments revealed that TtALOG2-1A, a TAW1-homologous gene, plays a significant role in regulating the transition of indeterminate BM fate. Finally, large-scale RNA-sequencing studies and quantitative real-time polymerase chain reaction (qRT-PCR) experiments revealed that members of the TtALOGs may act upstream of the TtMADS22, TtMADS47, and TtMADS55 genes to promote indeterminate BM activities. Our findings further knowledge on BM development in wheat.

This research focused on characterizing 30 Kaluheenati rice accessions, conserved at the Plant Genetic Resources Centre (PGRC), Sri Lanka, using morphological traits and molecular markers. The study aimed to assess the extent of diversity within the Kaluheenati collection, to identify accessions suitable for quality seed production, and identify duplications in the PGRC seed collection. The trial was conducted in 2022 Yala and 2022/23 Maha seasons at the PGRC. The study recorded 44 morphological traits and used 30 Simple Sequence Repeat markers, and significant morphological diversity was observed in the tested traits except for variety group, ligule shape, collar color, flag leaf angle, lemma and palea pubescence and panicle threshability. Principal component analysis and cluster analysis grouped the accessions into seven clusters highlighting the variations. SSR analysis detected 147 alleles, indicating a diverse gene pool. Polymorphic Information Content ranged from 0.31 to 0.75, indicating moderate to high levels of polymorphism. The phylogenetic tree revealed five distinct clusters, indicating genetic variations within the Kaluheenati accessions. Ten accessions (AC 016955, AC 016944, AC 012926, AC 004091, AC 006713, AC 004089, AC 004087, AC 005191, AC 005385, and AC 007802), including pure lines from the RRDI and conserved accession at International Rice Research Institute clustered together, demonstrating genetic similarities. Despite name similarities, no exact genetic duplications were observed. These findings emphasize the genetic diversity present within the conserved Kaluheenati accessions, highlighting the importance of correct identification and utilization for future breeding programs.