The researchers investigated the effect of increasing the time and complexity of crop rotation on crop yields in organic farming systems over a ten-year period.
They found that longer and more complex rotation using corn, soybeans, wheat and hay will yield 30% more corn than a single corn and soybean crop rotation. simple. Many secondary crops and alternating periods help to provide sufficient nitrogen and reduce the competition of grass, thereby increasing crop yields.
While the demand for organic meat and milk (non-artificial chemical foods) is increasing to about 20% per year in the US, most grains and pet food provide for These industries in the Mid-Atlantic region are all imported from other regions. To meet this local demand, farmers in the region need information about expected crop yields and effective management options.
Scientists from the US Department of Agriculture's Sustainable Agricultural Systems Laboratory (USDA) - Beltsville Agricultural Research Center of the US Department of Agriculture (ARS) in Maryland have studied the influence of Diverse organic farming systems for crop yields over a 10-year period.
The researchers collected data on crop yields, nitrogen uptake, grass densities, and the number of crops from Beltsville's Farming Systems Project (FSP) - this is trials of long-term cropping systems with two customary systems and three organic systems were established in 1996. Three organic systems differ in time and complexity of rotation.
The researchers investigated the effect of increasing the time and complexity of crop rotation on crop yields in organic agricultural systems over a ten-year period.They found that longer and more complex rotation using corn, soybeans, wheat and hay will yield 30% more corn than a single corn and soybean crop rotation. simple.(Photo: iStockphoto / Tomas Bercic)
The study found that corn and soybean production in organic systems averaged 76% and 82%, respectively, for corn and soybean production in customary systems over the years with weather conditions. normal. Winter wheat production in all systems is similar. The lower yield of organic corn in the original system is due to the low amount of nitrogen available in organic systems, which depends on legumes and manure. Grass invasion also contributes to reduced corn grain production in organic systems. For soybeans, grass encroachment alone explains the yield differences between organic systems and customary systems.
In organic systems, the timing and complexity of rotation have a strong influence on the yield of corn grain. An average crop of corn, soybeans, wheat and grass produced 30% more corn than the crop rotation between corn and soybeans, and 10% more than a crop rotation. between corn, soy and wheat. These differences are due to an increase in the amount of nitrogen available and the reduction of grass encroachment with increased time and complexity of rotation. The timing and complexity of rotation do not affect the yield of soybeans and wheat.
Dr. Michel Cavigelli, the lead researcher, said: 'These research results show that longer and more complex rotations can help us target the two most important production challenges in production. Export of organic cereals: that is to supply enough nitrogen to the needs of the crop and to reduce grass encroachment. '
This research helps farmers and people who consider transitioning to the choice of organic crop rotation most suitable for the Mid-Atlantic region. Since the FSP project is one of the long-term cropping systems trials including diversified organic crop rotation, these results will also become a concern for organic food farmers. and people cooperating with organic food farmers around the world.
The ARS and USDA Department of Sustainable Agricultural Systems continues to carry out this study to enhance the available nitrogen in the soil and reduce grass encroachment in organic grain rotations.
USDA and ARS funded this study.
1. Cavigelli, Michel A., Teasdale, John R., Conklin, Anne E. Long-term agronomic expression of traditional and organic crops in the Mid-Atlantic region. Agron J, 2008 100: 785-794 DOI: 10.2134 / agronj2006.0373