Fruit cell division

Developing fruits are rich sources of cytokinins, which are found in tissues where rapid cell-divisions are occurring, and are considered to play an important role in the regulation of cell division in fruit.397,424 Letham424 concluded that shape of the apple at maturity probably depends upon the balance between gibberellins and cytokinins in the immature fruit, and that apple varieties differ in their response to these compounds. 

After fruit set, and through the stages of cell division and cell expansion leading to maturation, there is a constant decrease in the rate of... 

Potassium contributes to the formation of sugars, carbohydrates, proteins and to cell division adjusts water balance enhances the flavor, color, and oil content of fruits and is very important for leafy crops. Potassium deficiency produces a spotted, curled, or burned appearance to leaves and lowers crop yields. Potassium fertilizers are applied in the following forms potassium chloride, potassium sulfate, potassium nitrate, and wood ash. 

Folpet is a protective leaf fungicide. Its mode of action inhibits normal cell division of a broad spectrum of microorganisms. It is used to control cherry leaf spot, rose mildew, rose black spot, and apple scab. It is used on berries, flowers, ornamentals, fruits and vegetables, and for seed- and plant-bed treatment. Folpet also finds use in paints, plastics, and treatment of internal and external structural surfaces of buildings to control fungal attack.50,52... 

Figure 3 shows the hypothetical kinetics of growth, respiration and relative hormone levels in a climacteric fruit at different stages of its life cycle. Hypothetical hormone levels during development and ripening have been speculated on before (13). The rationale for this outline is based on the known influences of the various hormones on cell division,... 

In plants, aliphatic di- and polyamines have been implicated in many processes including rapid cell division, fruit development, stress response and senescence (Evans and Malmberg, 1989 Galston and Kaur-Sawhney, 1995). Amine oxidases catalyse the eatabolism of biogenic amines and hence could be involved in regulating sueh eellular processes. It is eonve-nient to separate discussion of the roles of the copper-containing idiamine... 

Bacteria are microscopic, one-celled organisms. They usually reproduce by single cell division. Each new cell possesses all the characteristics of the parent cell. Bacteria can multiply fast under warm, humid weather conditions. Some can divide every 30 minutes. Bacteria may attack any part of a plant, either above or below the soil surface. Many leaf spots and rots are caused by bacteria. Table 3.8 shows examples of leaf spots and fruit rot. 

Anatomy of the abscission zone at the base of mature fruits has been investigated in apples (10), cherries (11), citrus (12), and olives (13) and has been discussed as related to mechanical fruit removal (2, 14), The histochemistry of the separation layer of mature fruit is very similar to that of leaves of citrus (15) and bean (16,17), The actual separation occurs through one or more processes in the separation zone (a) a weakening of the cementing ability of the middle lamella between cells, and (b) a softening of the entire cells (17), In some plants, the abscission zone is structurally differentiated as a layer of compact cells or as a zone of localized cell division in other species, abscission may occur across a transect of cells which show little or no visible diflFerentiation (18). Thus, major components of the separation process involve the dissolution of middle lamella and lysis of cell walls or entire cells in the separation zone, but this is not necessarily associated with distinctive morphological characteristics (19). 

Folpet inhibits cell division in many microorganisms. As a fungicide, it is used to control cherry leaf spot, rose mildew, rose black spot, and apple scab and is also used on berries, flowers, fruits, and vegetables for seed treatment. 

Foiate RDA F 400 [xg M 400 [xg Citrus fruits dark green vegetables fortified cereals and breads legumes Impaired cell division and growth megaloblastic anemia neural tube defects... 

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