Articles
Do plant growth regulators really regulate growth? Plant development and plant growth are not synonymous
Article number
1457_53
Pages
421 – 426
Language
English
Abstract
Much scientific literature refers to plant development and growth as though they are synonymous.
While plant physiology texts and horticulture texts emphasize the roles of various plant hormones in coordinating plant development, they simultaneously refer to them as plant growth regulators.
On the other hand, the same texts emphasize assimilation processes and the important role of carbohydrate and nutrient availability, as well as water relations, in enabling growth to occur.
The terms growth and development are often used interchangeably, and the literature rarely emphasizes the difference between plant development and plant growth.
This causes confusion and a lack of clear thinking when attempting to develop explanations for plant growth responses in specific circumstances.
Hormone physiologists often attempt to explain particular growth responses in terms of hormonal theory, whereas environmental physiologists will likely explain the same responses in terms of environmental conditions and the availability of resources required for growth.
In this paper, I will argue for a clearer differentiation between plant development and plant growth and suggest that plant hormones should not be thought of as plant growth regulators, but rather as plant development coordinators.
Plant development coordinators (plant hormones) establish the conditions necessary for plant growth, but the availability of plant growth substances, carbohydrate and nutrient availability, along with temperature and water relations, often regulate plant growth rates.
Treating development and growth as separate but interdependent processes could clarify much of the understanding of the underlying processes involved in regulating plant growth.
These concepts will be discussed in the context of understanding the mechanisms involved in several physiological phenomena of fruit trees.
While plant physiology texts and horticulture texts emphasize the roles of various plant hormones in coordinating plant development, they simultaneously refer to them as plant growth regulators.
On the other hand, the same texts emphasize assimilation processes and the important role of carbohydrate and nutrient availability, as well as water relations, in enabling growth to occur.
The terms growth and development are often used interchangeably, and the literature rarely emphasizes the difference between plant development and plant growth.
This causes confusion and a lack of clear thinking when attempting to develop explanations for plant growth responses in specific circumstances.
Hormone physiologists often attempt to explain particular growth responses in terms of hormonal theory, whereas environmental physiologists will likely explain the same responses in terms of environmental conditions and the availability of resources required for growth.
In this paper, I will argue for a clearer differentiation between plant development and plant growth and suggest that plant hormones should not be thought of as plant growth regulators, but rather as plant development coordinators.
Plant development coordinators (plant hormones) establish the conditions necessary for plant growth, but the availability of plant growth substances, carbohydrate and nutrient availability, along with temperature and water relations, often regulate plant growth rates.
Treating development and growth as separate but interdependent processes could clarify much of the understanding of the underlying processes involved in regulating plant growth.
These concepts will be discussed in the context of understanding the mechanisms involved in several physiological phenomena of fruit trees.
Publication
Authors
T.M. DeJong
Keywords
hormones, plant growth regulators, dwarfing rootstocks, growth rates
Online Articles (96)