Histogenesis of the inflorescence and flower of Triticum aestivum L.

1955 ◽  
Vol 3 (1) ◽  
pp. 1 ◽  
Author(s):  
C Barnard
Keyword(s):  
Triticum Aestivum ◽  
Outer Layer ◽  
Apical Meristem ◽  
Floral Morphology ◽  
Triticum Aestivum L ◽  
Leaf Primordia ◽  
Periclinal Division ◽  
Flower Primordia ◽  
Foliage Leaf ◽  
Vegetative Buds

In Triticum the apical meristem of the spike and spikelets is similar to that of the vegetative axis: a two-layered tunica encloses a central corpus. Leaf primordia arise by the periclinal division of cells of the tunica, the corpus contributing nothing to their development. Spikelet primordia are initiated in periclinal divisions of cells of the outer layer of the corpus (sub-hypodermis). Their mode of origin is comparable with that of vegetative buds. The glumes and lemmas arise in the same manner as the foliage leaf; the flower primordia by divisions in the sub-hypodermis like the spikelets. The early histogenesis of the palea, lodicules, and carpel is also essentially the same as that of the foliage leaf, whilst the stamens arise as cauline structures like the spikelets and flower primordia. The ovule is derived directly from the apex of the flower primordium and the integuments originate in the manner of foliar structures. The significance of these observations in the interpretation of the floral morphology of Triticum is discussed.

DEVELOPMENTAL MORPHOLOGY OF THE INFLORESCENCE IN HEXAPLOID WHEAT CULTIVARS WITH AND WITHOUT THE CULTIVAR NORIN 10 IN THEIR ANCESTRY

1973 ◽  
Vol 53 (1) ◽  
pp. 7-15 ◽  
Author(s):  
JOHN E. FISHER
Keyword(s):  
Triticum Aestivum ◽  
Apical Dominance ◽  
Triticum Aestivum L ◽  
Leaf Primordia ◽  
Developmental Pattern ◽  
Morphological Development ◽  
Wheat Cultivars ◽  
Developmental Morphology ◽  
Secale Cereale L ◽  
The Individual

The morphological development of the spike in short-statured hexaploid wheats (Triticum aestivum L.) derived from the cultivar Norin 10, and in Norin 10 as well, was markedly different from that in standard hexaploid wheats. In Norin 10 and its derivatives, the single ridges (slowly growing leaf primordia) on the elongating apex were considerably larger and spikelet primordia initiation and expansion were markedly delayed, resulting in a long apex with many single ridges. When spikelet development commenced, it was much more synchronous and hence gave rise to longer heads than in standard wheat in which spikelet development began soon after the start of the elongation of the apex. In most Norin 10 derivatives, more spikelets were initiated than in standard wheat. Apical dominance in the spike appeared to be stronger than in standard wheats. Also, apical dominance within the individual spikelets appeared to be greater, the net result being more fertile florets per spikelet. The developmental pattern of the spike of Norin 10 and its derivatives resembled, to a marked degree, the developmental pattern of rye (Secale cereale L.).

Ultrastructure of the cuticular membranes of the developing wheat grain

1975 ◽  
Vol 53 (18) ◽  
pp. 2077-2087 ◽  
Author(s):  
I. N. Morrison
Keyword(s):  
Triticum Aestivum ◽  
Outer Layer ◽  
Outer Integument ◽  
Triticum Aestivum L ◽  
Ultrastructural Level ◽  
Ultrastructural Changes ◽  
Grain Development ◽  
Wheat Grain ◽  
Maximum Thickness ◽  
Days After Anthesis

The distribution of cuticular membranes within the mature wheat ovule (Triticum aestivum L. cv. Heron) and the subsequent changes in these layers during grain development were investigated at the ultrastructural level. At anthesis, the inner epidermis of the pericarp and the outer integument are separated by two, thin, osmiophilic, cuticle-like lamellae. Similar osmiophilic boundaries, also double in nature, are evident between the outer and inner integuments and between the inner integument and the nucellar epidermis. By 7 days after anthesis, only the outer layer of cells of the inner integument and the nucellar epidermis are bounded by cuticularized layers, which, by this time, are recognizable as the developing outer and inner cuticles, respectively, of the mature caryopsis. Between 7 and 14 days after anthesis, the outer cuticle assumes a highly reticulate appearance in section and is delineated on the outside by a cutin layer, 90–120 nm in thickness. By 17 days both the outer and inner cuticles have attained maximum thickness, varying from 3.0 to 3.6 μm and 0.8 to 1.1 μm, respectively. Unlike the outer cuticle, the inner cuticle has no distinct internal substructure. The two are closely appressed by 4 weeks after anthesis and show no further ultrastructural changes.

SEM study of the morphological effects of kinetin and zeatin on the growth and development of the apical meristem in wheat

1995 ◽  
Vol 53 ◽  
pp. 978-979
Author(s):  
G. M. Hutchins ◽  
J. S. Gardner
Keyword(s):  
Growth And Development ◽  
Furfuryl Alcohol ◽  
Apical Meristem ◽  
Plant Cells ◽  
Triticum Aestivum L ◽  
Morphological Development ◽  
Naturally Occurring ◽  
Chinese Spring Wheat ◽  
Sem Study ◽  
Moist Environment

Cytokinins are plant hormones that play a large and incompletely understood role in the life-cycle of plants. The goal of this study was to determine what roles cytokinins play in the morphological development of wheat. To achieve any real success in altering the development and growth of wheat, the cytokinins must be applied directly to the apical meristem, or spike of the plant. It is in this region that the plant cells are actively undergoing mitosis. Kinetin and Zeatin were the two cytokinins chosen for this experiment. Kinetin is an artificial hormone that was originally extracted from old or heated DNA. Kinetin is easily made from the reaction of adenine and furfuryl alcohol. Zeatin is a naturally occurring hormone found in corn, wheat, and many other plants.Chinese Spring Wheat (Triticum aestivum L.) was used for this experiment. Prior to planting, the seeds were germinated in a moist environment for 72 hours.

Sign in / Sign up

Export Citation Format

Share Document