section_path: Breeding objectives/For higher yields
section_name: For higher yields
paragraph_text: For higher yields
  
  The presence of certain versions of wheat genes has been important for crop yields. Genes for the 'dwarfing' trait, first used by Japanese wheat breeders to produce Norin 10 short-stalked wheat, have had a huge effect on wheat yields worldwide, and were major factors in the success of the Green Revolution in Mexico and Asia, an initiative led by Norman Borlaug. Dwarfing genes enable the carbon that is fixed in the plant during photosynthesis to be diverted towards seed production, and they also help prevent the problem of lodging. "Lodging" occurs when an ear stalk falls over in the wind and rots on the ground, and heavy nitrogenous fertilization of wheat makes the grass grow taller and become more susceptible to this problem. By 1997, 81% of the developing world's wheat area was planted to semi-dwarf wheats, giving both increased yields and better response to nitrogenous fertilizer.
  
  T. turgidum subsp. polonicum, known for its longer glumes and grains, has been bred into main wheat lines for its grain size effect, and likely has contributed these traits to Triticum petropavlovskyi and the Portuguese landrace group Arrancada. As with many plants, MADS-box influences flower development, and more specifically, as with other agricultural Poaceae, influences yield. Despite that importance, as of 2021 little research has been done into MADS-box and other such spikelet and flower genetics in wheat specifically.
  
  The world record wheat yield is about 17 tonnes per hectare (15,000 pounds per acre), reached in New Zealand in 2017. A project in the UK, led by Rothamsted Research has aimed to raise wheat yields in the country to 20 t/ha (18,000 lb/acre) by 2020, but in 2018 the UK record stood at 16 t/ha (14,000 lb/acre), and the average yield was just 8 t/ha (7,100 lb/acre).