Developing drought-tolerant corn hybrids
Drought tolerant corn varieties have been developed using the “native gene” approach. This refers to using traditional plant breeding techniquzes, but with an added twist from using cutting edge molecular tools. In this manner, breeders conduct crossing experiments to determine the relative chromosome location of these native drought tolerant genes, and then use marker-assisted selection to help move along the breeding process more efficiently.The “native gene” approach has allowed breeders to bring in more than one gene affecting drought tolerance. In contrast, a transgenic/biotech approach (which involves genetic engineering) introduces a single new gene into corn from another organism.
How RNA Chaperones are Being Bred into Hybrids
Genes not present in any corn germplasm can be incorporated and then bred into elite crop lines through “native approaches.” These biotech-derived varieties are still in the industry development pipelines and not yet available to producers. Let’s take a look at one drought tolerant trait in the pipeline that uses RNA chaperones.
RNA chaperones are proteins that help produce and protect other proteins during times of stress. Although the specific mechanisms aren’t yet fully understood, in general, RNA chaperones help make sure that RNA molecules and critical plant proteins maintain their proper shape. Therefore, even under drought stress, critical proteins produced by the plant fold into their proper shape. If the shape of a protein is damaged, it cannot properly perform its function. During the reproductive growth stages, damaged proteins can lead to yield loss. RNA chaperones help stabilize yield even during drought conditions.
You may hear the term “precision phenotyping” as you research corn varieties for your operation. This term refers to a set of tools and designed experiments which help breeders determine which specific genes and/or traits contribute the most toward drought tolerance. Careful control of the environment and precise observations are necessary to accurately assess the drought tolerance levels of corn lines/varieties. In an effort to control the growing environment, fields with uniform soil conditions are selected. These fields also need to meet certain requirements in terms of latitude, altitude, and soil fertility. Researchers select low rainfall areas that would be able to grow good crops if water were present. Drip irrigation is typically used in to control the amount of water the plants receive.