The Lack of Grain Sizing on Wheat or Barley


Grain sizing on either wheat or barley is determined by how early the plant dies. If the plant lives longer the grain sizing and the number of grains per seed head will become greater. The maximum yield will be obtained when the grain is ready for harvest and the stem is still green.


During climatic stress conditions (soil moisture, temperature and sunlight) a wheat plant will normally accumulate high levels of ABA and ethylene which tends to shorten a plant's life. In other words, most of our cereal grains do not ripen, they just die early.

The deaths of wheat and barley plants are determined by the lack of cel division in the root system. In other words, the plant grows from the root upward and the plant dies from the root upward.

If we are going to continue to have our cereal grains produce normally, with more seeds per head and greater seed filling, the plant (roots) must be kept alive after the flag leaf initiation stage of growth. This implicitly implies that the plant must be protected against drought, high temperatures, and the shading effect that takes place on the bottom part of the plant.

Plants normally die when high levels of abscisic acid and ethylene are present due to plant stress. If either ethylene or abscisic acid can be kept at a lowerlevel, the plant will not die. It will have a longer period of time to fill the grains. The only way to extend grain filling is either to greatly reduce the level of ethylene or abscisic acid which accumulates when a plant is under stress.

Stress occurs from the roots upward, it does not occur from the top downward. Therefore, continuous new root growth during the grain filling period is necessary.

When wheat or barleyplants begin to die, the dying always starts in the stressed area of the field. Because ethylene, which is a gas, can pass from the dying plant to its neighbors, these dead spots in the field grow from the stressed areas outward in a circumference to more healthy plants. It is interesting to note how fast this ethylene will spread from stressed plants to healthy plants and cause a healthy plant to begin to die. Within a period of 7 days the whole field can be dead ---- which we refer to as ripening.

If this stress ethylene can be eliminated from the stressed spots in the field, all plants in the field will live a longer period of time and have a greater number of days to size the seed.


When the wheat or barley plant undergoes the hormonal change from vegetative to reproductive, the level of ethylene and abscisic acid greatly increases. This causes the decrease in cytokinin and auxin which are responsible for cell division in the new grains that are developing on the seed head.

The application of Bio-Forge at flag leaf emergence will enable the plant to hormonally pass through the problem area of change from vegetative to reproductive. The application of Bio-Forge will tend to reduce the ethylene and abscisic acid formation, which causes root growth to cease and plant tissue to die.

This is a simple application that can be applied by a ground spray or aerial application.

Bio-Forge should greatly reduce the negative effect caused by drought, high temperatures and the lack of sunlight to a full part of the plant.

J/JHS Articles/PEP - The Lack of Grain Sizing on Wheat and Barley 031507 bc