Foliar fertilizer application rates and recommendation for the tobacco

To disclose in detail this macro stage, it is necessary to indicate that here occurs the formation of second-order growth cones, the formation of the available number of flowers in the inflorescence with the laying down of flower covering organs, the formation of anthers (microsporogenesis) and stigmas (megasporogenesis), the formation of a larger number of synchronously developed productive stems. There is intensive growth of organs in length, formation of ovules and pollen grains.

Applying nitrogen and phosphorus fertilizers can increase the number of flowers in an inflorescence. Although the structural organization of the vascular plant is relatively loose, the development of different parts is well coordinated. Control depends on the movement of chemicals, including nutrients and hormones. An example of correlation is shoot and root growth. The increase in the aerial part is accompanied by an increased need for water, minerals and mechanical support, which are satisfied by the coordinated growth of the root system. Several factors seem to be involved in control, as the shoot and the root affect each other mutually. The root depends on the shoot for organic nutrients, just as the shoot depends on the root for water and inorganic nutrients, and thus the flow of ordinary nutrients must play a role. However, more specific control can be provided by supplying the nutrients needed in very small quantities.

The root depends on the shoot for certain vitamins, and changes in supply reflecting the metabolic state of the above-ground parts can also affect root growth. In addition, hormonal factors affecting cell division pass upward from the root to the stem; although the exact role of hormones has not yet been established with certainty, they may be one of the ways in which the root system can influence the activity of the shoot apex. Secondary thickening control is another important example of growth correlation. As the size of the shoot system increases, the need for both greater mechanical support and enhanced transport of water, minerals, and elements is met by increased coverage of the stem through the activity of the vascular cambium. As a rule, the cambium of trees in temperate zones is most active in spring, when buds are budding and shoots are sprouting, creating a need for nutrients.

Cell division begins on each shoot and then spreads out from it. The terminal bud stimulates the cambium to divide rapidly through the action of two groups of plant hormones: auxins and gibberellins.

Inhibition of lateral buds, another example of a correlated growth reaction, illustrates a reaction opposite to that occurring when controlling cambial activity. Lateral buds are generally depressed, as axillary shoots grow slower or do not grow at all, while the terminal bud is active. This so-called apical dominance is responsible for the characteristic unit of trunk growth observed in many conifers and herbaceous plants, such as the mallow. Weaker dominance leads to a form with multiple branching. This fact that the lateral or axillary buds become more active when the terminal bud is removed is evidence of hormonal control. The flow of auxin from the shoot apex is partially responsible for the inhibition of axillary buds.

The nutritional status of the plant also plays a role, as verticillium dominance is strong when mineral supply and light are insufficient. Since the axillary buds are released from inhibition by treatment with substances that stimulate cell division, also called cytokinins, it has been suggested that these substances are also involved in the regulation of bud’s activity.

In this macro stage, the processes of formation of all organs of the flower inflorescence are completed, the development of flowers from the rudiments up to their opening. The largest upper internode continues to grow. Compound fertilizers are applied with an emphasis on nitrogen and trace elements such as zinc.

In terms of development, a flower can be viewed as a determinate growth axis of a shoot, with lateral members occupying areas of the leaves that differentiate as floral organs – sepals, petals, stamens, and pistils. In the transition to flowering, the apex of the stem undergoes characteristic changes, the most noticeable of which is the shape of the apex area, which is related to the type of structure to be formed, whether a single flower, as in the tulip, or a bunch of flowers (inflorescences), as in the lilac.

The area of cell division extends to the entire apex, and the end-cell RNA content increases. When a single flower emerges, lateral buds appear higher and higher on the sides of the apical dome, and the entire apex is absorbed in the process, after which apical growth ceases.