The KNAT1/BP gene in Arabidopsis thaliana is crucial for the development of abscission zones, which are important for plant growth. A mutant with a T-DNA insertion in KNAT1/BP shows short pedicles, downward-pointing siliques, and semidwarfism. This mutation affects cell division and elongation, leading to the observed phenotypes. The loss of KNAT1/BP function also disrupts the development of abscission zones, which are involved in shedding plant parts. Gene expression analysis suggests that KNAT1/BP influences abscission zone development through hormone signaling and metabolism in Arabidopsis.