BTG 461 Bioresources Mgt What is plant breeding? Genetic improvement through crossing plants with desired traits and selecting progeny with improved performance and/or improved combinations of traits. “Accelerated” and “targeted evolution”.  Application of genetics principles to crop improvement.  Systematic procedures used to improve trait phenotypes by crossing and selection, directed manipulation of the genotype at the DNA sequence level, and introduction of new genes.

What is plant breeding? Modern plant breeding is an application of genetic principles. Crop improvement is a cyclic process of identifying new variation, crossing, selection, and fixing favorable traits. Fundamentally breeding is evolution by artificial selection.

Agricultural food production Each year humans re-create the food supply that feeds 6.15 billion people Reserves of staple foods would feed the world for less than two months and were as low as 48 days in 1995 800 million people go to bed hungry every night Food and Human nutrition http://www.harvestplus.org/ Vitamin A deficiency affects 750 million people

The success of plant breeding Increases in yield are derived both from improved varieties and from improved management. In vegetable crops, research suggests about a 50-50 split between genetic gain and gain attributed to management. Genetic gain in grain yield of 75 Kg ha-1 yr-1 for corn can be attributed to breeding. 1 ton/acre increase in yield every 30 years. Maize yields have increased 60% to 120% in the U.S. since 1940 (Cooper et al., 2004. Genomics, Genetics, and Plant Breeding: A Private Sector Perspective. Crop Science. 44:1907-1913).   “Green revolution” varieties have increased yields 2 to 3 fold in many “developing” nations (Knight, 2003).

The crisis in plant breeding Public sector research into classical crop breeding is declining dramatically (Knight, 2003).   US, European, World Bank decreased funding for Consultative Group on International Agricultural Research (CIGAR). Centro Internacional de Mejoramiento de Maiz Y Trigo eliminated the Obregon part of the Toluca-Obregon shuttle used in the two-cycle/year “shuttle breeding” wheat improvement program.  Number of students trained in plant breeding is decreasing. Shift from “public” to commercial sector than at Universities or Government research organizations. (attributed to changes in intellectual property laws)