2F), a more extreme growth of scutellum cells causes the displacement of the root cap to a lateral position and places the first leaf primordium
in a basal location (Tiwari 1970; Goetghebeur 1986).
Stolon parts were treated for 5-10 min, spore, leaf primordium
, circinate part of young fronds and leaf primordium
, procured from in vitro-raised sporophytes, were treated for 2-5, 2-10, 5-10, and 1-2 min, respectively.
Thus colleter secretion products on the abaxial side are secreted into the space between the stipules where there is a leaf primordium
to protect it.
Cytohistological zonation similar to the mature vegetative apex occurs at the time the first leaf primordium
is being initiated.
Panicle initiation is largely a process of differentiation, while leaf-tip appearance is largely a process of expansion, and studies with millet and sorghum have shown that PI (and leaf primordium
initiation) is not as sensitive to high temperature episodes and vapor pressure deficit as leaf expansion (Ong, 1983; Hamdi et al., 1987).
PIN1 localization at the SAM periphery allows auxin to accumulate and to promote leaf primordium
Therefore, while fitting regression models, [D.sub.1] was restricted to observed durations of MS and tillers averaged over twelve plants, i.e., the duration of leaf primordium
initiation was restricted to 126 ATU for MS; to 138 ATU for T0 and T1, which appeared simultaneously; to 180 ATU for T2; and to 225 ATU for T3, T10 and T11, which appeared simultaneously.
Development of these varieties differs in size and shape of leaf primordium
at initiation, in the timing of leaf incision, and in growth rate.
Five Arachis hybrids provided healthy apical meristems (meristem with zero or one leaf primordium
from micropropagated nodal explants.
As far as is known in mimosoid legumes, at least one bud is formed at every node concomitant with, or slightly after, formation of the leaf primordium
. Sylleptic buds are those buds that continue development while the RGU on which they are formed is still completing development itself: that is, before the complete sequence of metamers has been produced.
The uppermost or anodic portion of the bifurcated primordium becomes a stolon complex (similar to that described for Stratio tes), while the other, cathodic portion of the primordium bifurcates again, forming the stolon in the middle and another stolon complex in the position farthest from the next youngest leaf primordium
. When the ramet becomes fertile, the stolon complex on the anodic side of the axillary complex is replaced by either a male or a female inflorescence (Figs.
A more subtle disagreement concerns the nature of the earliest stage of leaf development and the related question of the boundary between foliar and cauline tissues at the base of the leaf primordium
. Many workers over the years have described an essentially unicellular pattern of leaf initiation, in which one cell of the surface layer of the shoot apex, the "leaf mother cell" of Bierhorst (1977), becomes enlarged and undergoes a series of oblique anticlinal divisions to become the new leaf apical cell [ILLUSTRATION FOR FIGURE 3 OMITTED].