We report two new recessive mutations in Arabidopsis, mgoun1 and mgoun2 which cause a reduction in the number of leaves and floral organs, larger meristems and fasciation of the inflorescence stem. Although meristem structure is affected in the mutants, we provide evidence that its overall organisation is normal, as shown by the expression patterns of two meristem markers. Microscopical analyse...

Plant architecture consists of repeating units called phytomers, each containing an internode, leaf and axillary meristem. The formation of boundaries within the phytomer is necessary to differentiate and separate these three components, otherwise some will grow at the expense of others. The microRNA-targeted SBP-box transcription factor tasselsheath4 (tsh4) plays an essential role in establish...

Root elongation requires cell divisions in the meristematic zone and cell elongation in the elongation zone. The boundary between dividing and elongating cells is called the transition zone. In the meristem zone, initial cells are continuously dividing, but on the basal side of the meristem cells exit the meristem through the transition zone and enter in the elongation zone, where they stop div...

The shoot meristem is a proliferating, changing cell population yet displays a stable organization. Recent studies have addressed how signaling processes coordinate the behaviour of shoot meristem cells.

Leaves originate from the shoot apical meristem, a small mound of undifferentiated tissue at the tip of the stem. Leaf formation begins with the selection of a group of founder cells in the so-called peripheral zone at the flank of the meristem, followed by the initiation of local growth and finally morphogenesis of the resulting bulge into a differentiated leaf. Whereas the mechanisms controll...

ABSTRACT Large-scale oil palm propagation (Elaeis guineensis Jacq.) is difficult due to its unique apical meristem. In this context, micropropagation allows the multiplication of seedlings in vitro and storage germplasm elites. This study aimed induce embryogenic calluses from leaves plants low concentrations auxins observe maintenance these characteristics during cultivation. Calluses were ind...

A hyaline sterile fungus forming epiphyllous mycelial nets was isolated from meristem cultures of Mentha piperita. Histological studies indicated that the culture isolate is able to colonize stems and leaves with no damage to the host plant. In vitro-grown peppermint plants displayed enhanced vegetative growth when infected by the fungus, with mycelium extending from green tissues to growing ro...

A combination of environmental factors and endogenous cues trigger floral meristem initiation on the flanks of the shoot meristem. A plethora of regulatory genes have been implicated in this process. They function either as activators or as repressors of floral initiation. This review describes the mode of their action in a regulatory network that ensures the correct temporal and spatial contro...