biostudies-literatureUnknown3(4)Tsai MYAcademia SinicaStomata are a pivotal adaptation of land plants and control gas exchange. While most plants present solitary stomata, some plant species experiencing chronic water deficiency display clustered stomata on their epidermis; for instance, limestone-grown begonias. Moreover, the membrane receptor TOO MANY MOUTHS (TMM) plays a major role in spacing stomata on the epidermis in <i>Arabidopsis</i>, but the function of its <i>Begonia</i> orthologs is unknown. We used two Asian begonias, <i>Begonia formosana</i> (single stomata) and <i>B. hernandioides</i> (clustered stomata), to explore the physiological function of stomatal clustering. We also introduced the <i>Begonia TMM</i>s into <i>Arabidopsis tmm</i> mutants to study the function of <i>Begonia</i> TMMs. <i>B. hernandioides</i> showed higher waPlant-environment interactions (Hoboken, N.J.)141-154https://www.ebi.ac.uk/biostudies/studies/S-EPMC10168073biostudies-literatureStomatal clustering in <i>Begonia</i> improves water use efficiency by modulating stomatal movement and leaf structure.PMC10168073Kuan CYang HAHo CKChung KFTsai MYGuo ZLfalseStomatal clustering in <i>Begonia</i> improves water use efficiency by modulating stomatal movement and leaf structure.Stomata are a pivotal adaptation of land plants and control gas exchange. While most plants present solitary stomata, some plant species experiencing chronic water deficiency display clustered stomata on their epidermis; for instance, limestone-grown begonias. Moreover, the membrane receptor TOO MANY MOUTHS (TMM) plays a major role in spacing stomata on the epidermis in <i>Arabidopsis</i>, but the function of its <i>Begonia</i> orthologs is unknown. We used two Asian begonias, <i>Begonia formosana</i> (single stomata) and <i>B. hernandioides</i> (clustered stomata), to explore the physiological function of stomatal clustering. We also introduced the <i>Begonia TMM</i>s into <i>Arabidopsis tmm</i> mutants to study the function of <i>Begonia</i> TMMs. <i>B. hernandioides</i> showed higher wa2022-01-01T00:00:00Z2022 Aug2025-07-05T03:04:16.472Z2025-07-05T03:04:16.472ZS-EPMC101680733728360710.1002/pei3.10086