scholarly journals Does Ethylene Play a Role in the Release of Lateral Buds (Tillers) from Apical Dominance in Oats?

1982 ◽  
Vol 70 (3) ◽  
pp. 811-814 ◽  
Author(s):  
Marcia A. Harrison ◽  
Peter B. Kaufman
1987 ◽  
Vol 65 (7) ◽  
pp. 1427-1432 ◽  
Author(s):  
Gordon I. McIntyre

A previous investigation of apical dominance in the rhizome of Agropyron repens showed that keeping the rhizome in a high humidity promoted the outgrowth of the lateral buds but strongly inhibited the growth of the rhizome apex. A study of these related responses demonstrated that the inhibition of apical growth was not prevented by excision of the lateral buds and was also induced when only the apex of the rhizome received the high humidity treatment. The necrotic lesions that developed in the arrested apices and the reduction of apical inhibition produced by various Ca treatments indicated that the inhibition of apical growth was caused by Ca deficiency. When the rhizome apex was exposed to low humidity, a localized high-humidity treatment of the lateral buds did not release the buds from apical dominance in low-N rhizomes but strongly promoted bud growth at a higher N level. When growth of the buds was induced at low humidity by increasing the N supply, the increase in bud weight was preceded by an increase in the water content of the bud when expressed on a dry weight basis. These results agree with those of previous investigations and suggest that the interacting effects of N and humidity on the water status of the buds may play a significant role in the mechanism of apical dominance.


1984 ◽  
Vol 116 (9) ◽  
pp. 1277-1279 ◽  
Author(s):  
Arthur E. Weis

Plant galls are growth deformities developed under the influence of parasitic insects. The process of differentiation of normal plant tissue into gall tissue has been examined by many authors (Kostoff and Kendall 1929; Rohfristch 1977; see also Mani 1964) but less effort has been made to study the effects of the gallmaker on plant tissues outside the vicinity of active gall formation. Negative effects on the overall growth of the host plant can be expected because the gall acts as an energy and nutrient sink (Palct 1972; Hartnett and Abrahamson 1979), which can cause abnormal patterns of resource allocation among plant organs.


1969 ◽  
Vol 47 (7) ◽  
pp. 1189-1197 ◽  
Author(s):  
Gordon I. McIntyre

When plants of Agropyron repens L. Beauv. are grown at a high nitrogen level (210 p.p.m. N) apical dominance in the rhizome is sufficiently reduced to permit the continued growth of the lateral buds. If, however, the rhizome is isolated from the parent shoot the dominance of the apex is markedly increased and lateral bud growth is strongly inhibited.Experiments with these isolated, high-nitrogen rhizomes showed that apical dominance could be significantly reduced either by increasing the length of the rhizome or by retarding the growth of the rhizome apex by exposing it to light. The growth potential of the lateral buds declined rapidly as the duration of their attachment to the rhizome apex was increased. This effect was associated with the translocation of carbohydrate to the rhizome apex and could be overcome by providing the isolated buds with a 2% sucrose solution. When buds were isolated from the rhizome apex before their growth potential was exhausted a marked increase in their carbohydrate content was apparent after 48 h. This increase was associated with their resumption of growth. Buds still attached to the apex could be released from inhibition by supplying sucrose solutions to the cut end of the rhizome.The results suggest that, under the experimental conditions, apical dominance was due primarily to competition for a limited carbohydrate supply.


Nature ◽  
1964 ◽  
Vol 201 (4922) ◽  
pp. 939-940 ◽  
Author(s):  
TSVI SACHS ◽  
KENNETH V. THIMANN

1969 ◽  
Vol 68 (4) ◽  
pp. 335-340
Author(s):  
Osi Mozie

The nature of shoot dominance in white yam tubers (Dioscorea rotundata Poir) was studied under ambient conditions in the conventional yam storage barn. Whole tubers sprouted only at the proximal ends (i.e. the morphological bases). The single basal shoot formed per sprouting whole tuber inhibited the formation of lateral shoots along the tuber axis. Separating the basal end by sectioning the tuber into three regions namely "head" (i.e. basal or proximal region), middle region and "tail" (i.e. apical or distal region), appeared to stimulate the formation of lateral shoots on the surfaces of the tuber pieces below the basal region. Separating the basal region from the entire tuber by sectioning appeared to remove the stress under which the lateral buds had existed in the intact tuber. This response indicated a strong "basal dominance" of basal shoots in sprouting intact or whole yam tubers. The physiology of shoot dominance in whole yam tubers could be described as "basal dominance" rather than "apical dominance", since in sprouting intact or whole tuber it is the basal shoot (i.e. shoot of the morphological base or proximal end) that inhibits the development of lateral shoots along the tuber axis.


HortScience ◽  
1994 ◽  
Vol 29 (5) ◽  
pp. 541h-542
Author(s):  
Shiow Y. Wang ◽  
Miklos Faust ◽  
Michael J. Line

The effect of Indole-3-acetic acid (IAA) on apical dominance in apple (Malus domestica Borkh.) buds was examined by studying changes In proton density (free water) and membrane lipid composition in lateral buds. Decapitation induced budbreak and enhanced lateral bud growth. IAA replaced apical control of lateral bud paradormancy. Maximal inhibition was obtained when IAA was applied immediately after the apical bud was removed. Delaying this application weakens the effect of IAA. An increase in proton density in lateral buds was observable 2 days after decapitation, whereas the change in membrane lipid composition occurred 4 days later. Decapitating the terminal bud induced an increase in membrane galacto- and phospholipids. and the ratio of unsaturated to corresponding saturated fatty acids. Decapitation also induced a decrease in the ratio of free sterols to phospholipids in lateral buds. Application of IAA to the terminal end of decapitated shoots inhibited the increase of proton density and prevented changes in the membrane lipid composition of lateral buds.


1991 ◽  
Vol 71 (4) ◽  
pp. 1093-1099 ◽  
Author(s):  
R. A. Powelson ◽  
V. J. Lieffers

The regeneration potential and dormancy of lateral buds on rhizome segments near the parent shoot base or the distal rhizome apex of Calamagrostis canadensis were assessed. Apical and basal segments of various length, with and without the parental shoot base or rhizome apex attached, were planted 1 cm deep in loam soil. When the apex or base was attached axillary buds on the rhizome usually remained dormant. When the parental shoot base was excised, the bud closest to the rhizome base was more likely to sprout than more distal buds. When the apex was excised from the apical segments, more axillary buds emerged but no priority of bud development arose. Buds near the apex position generally had a higher frequency of sprouting than buds adjacent to the parental base. Rhizome segments adjacent to the apex were heavier and had a higher nonstructural carbohydrate content than rhizome segments adjacent to the parental base. Key words: Calamagrostis canadensis, rhizome, dormancy, apical dominance, competition


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hu Chen ◽  
Jianhui Tan ◽  
Xingxing Liang ◽  
Shengsen Tang ◽  
Jie Jia ◽  
...  

AbstractKnot-free timber cultivation is an important goal of forest breeding, and lateral shoots affect yield and stem shape of tree. The purpose of this study was to analyze the molecular mechanism of lateral bud development by removing the apical dominance of Pinus massoniana young seedlings through transcriptome sequencing and identify key genes involved in lateral bud development. We analyzed hormone contents and transcriptome data for removal of apical dominant of lateral buds as well as apical and lateral buds of normal development ones. Data were analyzed using an comprehensive approach of pathway- and gene-set enrichment analysis, Mapman visualization tool, and gene expression analysis. Our results showed that the contents of auxin (IAA), Zea and strigolactone (SL) in lateral buds significantly increased after removal of apical dominance, while abscisic acid (ABA) decreased. Gibberellin (GA) metabolism, cytokinin (CK), jasmonic acid, zeatin pathway-related genes positively regulated lateral bud development, ABA metabolism-related genes basically negatively regulated lateral bud differentiation, auxin, ethylene, SLs were positive and negative regulation, while only A small number of genes of SA and BRASSINOSTEROID, such as TGA and TCH4, were involved in lateral bud development. In addition, it was speculated that transcription factors such as WRKY, TCP, MYB, HSP, AuxIAA, and AP2 played important roles in the development of lateral buds. In summary, our results provided a better understanding of lateral bud differentiation and lateral shoot formation of P. massoniana from transcriptome level. It provided a basis for molecular characteristics of side branch formation of other timber forests, and contributed to knot-free breeding of forest trees.


1994 ◽  
Vol 119 (6) ◽  
pp. 1215-1221 ◽  
Author(s):  
Shiow Y. Wang ◽  
Miklos Faust ◽  
Michael J. Line

The effect of IAA on apical dominance in apple buds was examined in relation to changes in proton density (free water) and membrane lipid composition in lateral buds. Decapitation induced budbreak and enhanced lateral bud growth. IAA replaced apical control of lateral buds and maintained paradormancy. Maximal inhibition was obtained when IAA was applied immediately after the apical bud was removed; delaying application reduced the effect of IAA. An increase in proton density in lateral buds was observed 2 days after decapitation, whereas the change in membrane lipid composition occurred 4 days later. Removing the terminal bud increased membrane galacto- and phospholipids and the ratio of unsaturated to corresponding saturated fatty acids. Decapitation also decreased the ratio of free sterols to phospholipids in lateral buds. Applying thidiazuron to lateral buds of decapitated shoots enhanced these effects, whereas applying IAA to the terminal end of decapitated shoots inhibited the increase of proton density and prevented changes in membrane lipid composition in lateral buds. These results suggest that change in water movement alters membrane lipid composition and then induces lateral bud growth. IAA, presumably produced by the terminal bud, restricts the movement of water to lateral buds and inhibits their growth in apple.


HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 908C-908
Author(s):  
Miklos Faust

At the beginning and near to the end of the endodormant period, cytokinin-type growth regulators are effective to end dormancy in apple. The same growth regulators are not effective during the middle of this period. Terminal buds require less chilling than lateral buds to emerge from the dormant period. Lateral buds on decapitated shoots also require less chilling, indicating that auxin may be involved in dormancy. Replacing the terminal with IAA keeps water in bound state in the lateral buds, indicating the effect of IAA in dormancy. We have developed the theory that the beginning and the end of the winter-dormant period is governed by apical dominance. It appears that only this period can be manipulated either with dormancy avoidance methods or with dormancy-breaking chemicals. The central portion of the dormant period is not subject to manipulation. Therefore, it is important that the depth of the dormancy is quantified. Certain growth regulators can be used for determining the state of bud dormancy. Thidiazuron gives results within 2 to 4 days.


Sign in / Sign up

Export Citation Format

Share Document