Tag: plant hormones

ABA hormone is formed during leaf fall. It is a growth inhibiting hormone in plants which accelerates aging and inhibits germination and flowering. It also causes the closing of stomatal pore.

Certain fruits ripen with sudden rise in cellular respiration and ethylene production. Such fruits are called 'climacteric fruits'. Climacteric is considered final stage in fruit ripening process during which the fruit is maximum ripened with best taste for consumption. After that period, it starts to gradually deteriorate and the respiration returns to normal rate.

Leaf abscission is a detachment or fall of older leaves.It occurs at the base of the petiole. During abscission, high synthesize of ethylene is observed along with decrease in the concentration of auxin. Ethylene synthesizes enzymes like cellulase and pectinase which are involved in cell wall degradation. These enzymes loosens the cell wall and cells separate which ultimately leads to leaf abscission. 

Stress hormone is a hormone produced during adverse environmental conditions. Abscisic acid (ABA) is called as stress hormone. Due to this hormone, plants respond to stresses conditions like cold, drought. Stomatal closure under stress condition is due to this hormone. It also promotes seed dormancy under adverse condition.

Abscisic acid a plant hormone that plays important role abscission of leave. It inhibits stem elongation by inhibiting gibberellic acid. It prevents loss of dormancy in seeds. 

During ripening process, plants produce ethylene gas. To prevent overripening of bananas, the chemical reaction of ripening process needs to slow down. Cold temperatures will slow down the reaction and hence delay the ripening of banana. However, storing in freezer will slow down the ethylene emission more than refrigerating it.

Ethylene is a gaseous plant hormone. It is also called as ripening hormone. It is used externally to accelerate the fruit ripening process. Also during ripening process, controlled amount of carbon dioxide and oxygen is needed. For artificially ripening fruit, 80% C$ _2$H$ _4$ and 20% CO$ _2$ is used.

Abscisic acid is a plant hormone. It is also called as stress hormone. It causes abscission of leaves. During stress environmental condition, its concentration increases and induces bud dormancy. When favorable condition returns, bud dormancy is broken.

Ethylene is a plant growth regulator. It is also called as ripening hormone as it is responsible for speeding up ripening of fruits. Fruit ripening is accompanied by increase rate of respiration. Due to increased respiration, complex carbohydrates are broken down into simpler sugars and cell wall becomes soft.