Flower induction

Stimulate d-5 dwarf corn elongation, flower induction and primordia differentiation in winter rye... 

This phenomenon, which varies in intensity in different varieties, is characteristic of many other perennial fruit crops in which flower initials are laid down in the summer of the year before flowering. The sparse flower induction which accompanies a heavy crop was formerly attributed to depletion of the carbohydrate and nitrogenous reserves of the tree but, whilst alternate bearing may have developed as a means by which the tree could conserve its food reserves, the control mechanisms are clearly hormonal in nature. 

Block GA transport. A number of growth regulators are known which will block the transport of gibberellin from seed to bourse, and compounds such as 2,3>5-tri-iodobenzoic acid (TIBA) are effective in permitting flower induction to take place even in the presence of a heavy crop. But the flowers so induced set poorly and no increase in crop is obtained, probably because the food reserves of the tree have been depleted (Table III). So again, this is not a practical method. 

The following discussion will concentrate primarily on regulation, but, for clarity, includes substantial details of GA biosynthesis. An important consideration is the identity of the biologically active molecular species that are the target end-products of the pathway. For stem extension, this has been shown to be GA, in many species [1], but for other developmental processes, such as flower induction, the GA(s) involved have rarely been clearly identified. 

Gibberellins have been shown to act as mediators in responses to several environmental signals. A prime example is the induction of bolting in rosette plants in response to changes in photoperiod or to low temperatures [197], Increased GA biosynthesis is required for the rapid stem extension that precedes flowering in such plants, although not necessarily for flower induction... 

Yield and fruit quality Flower induction Ammonium thiosulfate... 

Flower Induction by 5-Triazine and Carbamate Derivatives in Seedlings of Asparagus Plants... 

The floral stimulus acts at the apex and therefore determination of the site of GA action is important in formulating logical hypotheses about the role of GAs in flower initiation. Although not examined in many species, the evidence indicates that GAs can affect flower initiation at different sites. Flower induction brought about by GAg treatments in Bryophyllum daigremontianum and Hyoscyamus niger is the result of GA action in the leaves, not the apex where the floral stimulus acts [21, 22]. The situation is quite different in the SDP Pharbitis nil and Impatiens balsamina, where it was determined that the apex is the site of GA action [ 16,25,27]. 

Flower induction Sex expression Flower bud development Pineapple and other bromeliads Cucumber, squash Apple... 

Now a few technical terms. During flower induction plants must be exposed to certain external conditions for a defined period of time. The time interval is known as the induction period and the efficacious external conditions as the inductive conditions. The natural, inductive, external conditions can, in many cases, be replaced by treatment with certain chemicals. External conditions under which plants remain in the vegetative state are called noninductive. 

The result of the experiment can be interpreted as follows under the conditions of induction genes involved in flower induction are activated. 

Since these first experiments, carried out in 1959, similar experiments with antimetabolities of transcription and translation have been carried out on very many other species that are dependent on temperature and length of day, with similar results. Thus, there is adequate demonstration that the genetic material participates in the processes of flower induction. 

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