Causes of Variety Mixing and Degeneration in the Latest Wheat Varieties and Control Methods

Variety mixing and degeneration in wheat is a common problem that occurs after superior wheat varieties have been planted for multiple seasons; once mixing and degeneration occur, the purity of the wheat seed is lower, quality deteriorates, stress resistance declines, and yield drops noticeably. So what causes wheat quality mixing and degeneration? How should it be controlled? Follow the editor to learn more about it.

I. Causes of quality mixing and degeneration

1. Mechanical mixing

During wheat sowing, threshing, seed drying, and transport and storage, artificial mixing occurs; this is currently one of the main causes of quality mixing and degeneration in stored wheat.

2. Biological mixing

Continuous natural hybridization between different varieties in the field leads to undesirable individuals appearing from segregation in the progeny and destroys the purity of the variety; this is called biological mixing. When mechanical mixing is severe, it further aggravates biological mixing and accelerates the rate of variety degeneration.

3. Variety mutation

During the promotion of new wheat varieties, various natural factors can cause some kind of mutation in wheat, and the mutant traits, especially the traits of outstanding individuals in production, are mostly worse.

4. Reasons related to wheat itself

The traits of some new wheat varieties bred by hybridization are unstable and their homozygosity is not high; these varieties will continue to segregate during cultivation, producing variant individuals and causing variety mixing and degeneration.

5. Low quality of selected seed for retention

In production, seed is not selected and retained according to the typical traits of the variety, resulting in poor seed quality; this can also lead to variety degeneration.

II. Control methods

1. First, strictly prevent mechanical mixing. At harvest, the seed must be harvested separately, transported separately, dried separately, and stored separately. During seed storage, it is also necessary to prevent insects, rodents, and mildew. Before sowing, the seed should be dried and disinfected to ensure excellent seed quality.

2. In the process of breeding improved wheat seed, attention should be paid to adopting isolation measures to strictly prevent biological mixing. Generally, three isolation methods can be used. The first is spatial isolation, that is, planting different wheat varieties at a certain distance apart; the second is temporal isolation, which uses staggered sowing dates so that the flowering periods of different wheat varieties are staggered; the third is barrier isolation, using tall crops, woods, and other barriers so that pollen from different varieties cannot reach the wheat seed production field.

3. When selecting and retaining seed, it is essential to strictly remove mixtures and inferior plants, especially plants, wheat ears, or grains that do not conform to the typical traits of the variety. At the same time, ears and grains contaminated by pests and diseases and poorly growing plants should also be removed in time.

The above is an introduction to the causes of variety mixing and degeneration in wheat and the control methods. I hope it can help you. To learn more related knowledge, please stay tuned to us.