Scientists reveal new mechanisms of “aggregation” of heterogeneous dominance

The core of the use of heterogeneous advantages is “poly” rather than “hybrid”. This is the new mechanism of “aggregation” revealed by researchers led by Academician Wang Hanzhong, chief scientist of the rapeseed genetic breeding innovation team of the Institute of Oilseeds of the Chinese Academy of Agricultural Sciences, which provides new theoretical guidance for promoting the further utilization of hybrid advantages. The research results were published in the international journal Plant Biotechnology Journal.

The core of the utilization of rapeseed hybrid advantages lies in the aggregation of excellent alleles. Photo courtesy of oil

Shi Jiaqin, co-corresponding author of the paper and associate researcher of the Institute of Oilseeds, introduced that hybrid dominance is a common biological phenomenon in which hybrid offspring are superior to their parents in terms of vitality, adaptability, resistance and yield, and the use of this phenomenon to cultivate hybrid varieties has become an important way to improve the productivity of agricultural animals and plants. The underlying theoretical basis for the use of heterozygosity is that alleles from both parents are more advantageous after heterozygosity, but studies have found that the correlation between the degree of genetic heterozygosity of hybrids and their level of heterozygosity is generally low.

Rapeseed is the largest oil crop in China, and canola oil is a bulk edible oil with reasonable fatty acid composition, which has a very important strategic position in the security of national edible oil supply. At present, the proportion of rapeseed hybrids in the world exceeds 70%, but the study of its genetic mechanism is relatively lagging behind. The study utilized a representative combination of canola for many years to systematically study at the phenotypic, genetic, and molecular levels.

It is found that most of the heterozygous performance of one gene does not exceed that of high-value parents, but the performance of multiple genes of excellent alleles from different parents can exceed that of high-value parents due to complementarity and accumulation effects, and the heterodominance multiplication effect of multiple yield constituent traits can produce a strong advantage in yield.

The above results show that in order to obtain an optimal hybrid combination, the most important principle is not to increase the genetic distance between parents, but to aggregate as many dominant genes as possible, regardless of whether they are heterozygous or homozygous. This conclusion breaks through the misunderstanding and points out the direction for the selection and breeding of strong dominant hybrids.

The team’s graduated doctoral students Ye Jiang and Liang Huabing are the co-first authors of the paper, and Wang Hanzhong and Shi Jiaqin are the co-corresponding authors. The research was supported by the National Key R&D Program and the Major Tasks of the Science and Technology Innovation Project of the Chinese Academy of Agricultural Sciences. (Source: China Science News Li Chen, Yubo)

Related paper information:

Source link

Related Articles

Leave a Reply

Your email address will not be published. Required fields are marked *

Back to top button