Tag: ethylene

Ethylene production by plants is autocalalytic, i.e., a small amount of ethylene will stimulate production of its larger amounts. Thus, a few ripe fruits will initiate ripening of nearby fruits. It is, therefore, a common practice to keep few ripe bananas with unripe bananas to hasten ripening.

Ethylene is a small hydrocarbon gas as well as a phytohormone. Some fruit will produce ethylene as ripening begins. Apples and pears are examples of fruit that produce ethylene with ripening. Ethylene is responsible for the changes in texture, softening, color, and other processes involved in ripening. Ethylene gas is used commercially to ripen tomatoes, bananas, pears, and a few other fruits postharvest. 

Ehtylene is a simple gaseous plant growth regulator. It is synthesized in large amounts by tissues undergoing senescence and ripening of fruits. It enhances the respiration rate during ripening of fruit. This rise in rate of respiration is called as respiratory climacteric. 
Exposure of plants to ethylene causes drooping of leaves and flowers, a phenomenon known as epinasty.

Flowering in pineapple is not only based on external factors like temperature, daylength but also is based on internal factors like phytohormones. Pineapple flowering can be artificially induced by activity of the ethylene and IAA (indoleacetic acid). During flowering of pineapple, low temperature stimulates ethylene biosynthesis. Other hormones which are involved in initiating pineapple flowering are a-naphthalene acetic acid (NAA), indolbutiric acid (IBA), 2,4-dichlorofenoxiacetic acid (2,4-D). 

Ethylene is a plant hormone. It is also called as ripening hormone as it is responsible for ripening of fruits. Fruit ripening is accompanied by increase rate of respiration. The climacteric respiration occurs during fruit ripening which is associated with increased ethylene production. Due to increased respiration, complex carbohydrates are broken down into simpler sugars and cell wall becomes soft. 

Ethylene is a metabolic product of methionine. It is synthesized from methionine amino acid by methionine cycle or yang cycle. Methionine is first converted to adenosylmethionine. It is then converted to Aminocyclopropane carboxylic acid. It is then oxidized to form ethylene. It is a gaseous plant hormone which stimulates ripening of fruits in plants.

Ethylene is a gaseous hormone that promotes transverse growth but inhibits lateral growth. They are produced by the amino acid methionine. It was found that ripened fruits produce this hormone, so when the ripened fruits are placed together with unripe fruits, the unripe fruits will get ripened due to the release of this gas. Ethylene evolution is highest at the time of ripening but it diminishes when the fruit matures and the evolution of gas got reduced.

• Ethylene is a simple gaseous PGR. 
• It is synthesised in large amounts by tissues undergoing senescence and ripening fruits. 
• Influences of ethylene on plants include horizontal growth of seedlings, swelling of the axis and apical hook formation in dicot seedlings. 
• Ethylene promotes senescence and abscission of plant organs, especially of leaves and flowers. 
• Ethylene is highly effective in fruit ripening
  
• So, the correct option is 'Ethylene'.