In 2014, apple growers across the United States planted about 1.8 million apple trees (10% of the national total) that feature fire blight-resistant, replant-tolerant, highly productive apple rootstocks. The number is expected to increase over the next 5 years to 5 million trees. This is thanks to the efforts of a Cooperative Research and Development Agreement partnership between the U.S. Department of Agriculture's Agricultural Research Service (ARS) and Cornell University scientists who developed the rootstocks, and the Cornell Center for Technology, Enterprise and Commercialization, which manages the technology transfer to stakeholders.
ARS and Cornell have a longstanding excellent collaborative project on breeding apple rootstocks that possess economically important traits such as dwarfing, precocity, high productivity and fruit quality, good cold-hardiness, and propagability. In addition, the rootstocks are resistant to key apple diseases such as fire blight and collar rot, insects, and components of replant disease. Many apple growers in the Northwest, Midwest, and Eastern regions of the U.S. had stopped planting new orchards because they lacked apple rootstocks resistant to fire blight. In 2006, the ARS-Cornell program patented and released two apple rootstocks that had proven to be resistant and more productive than the commercially available materials at the time. In 2010 and 2014, the program released five additional rootstocks that were targeted to mitigate replant disease, another problem faced by the industry.
More than 50 testing agreements were established with nurseries representing 95% of the U.S. production of apple rootstocks to assure market penetration and impact in the orchards. More than 40 demonstration sites at farms and research institutions nationwide were planted to bring in potential customers, along with the coordination of numerous field days and field visits where growers could witness the positive aspects firsthand. Over 100 presentations delineating salient characteristics about the technologies were delivered to grower and industry organizations, and more than 50 scientific and trade publications introduced the new technologies to decision makers in fruit companies. These efforts resulted in the production of 3 million apple rootstocks in 2014 worth about $3.5 million, and estimated to be worth about $19 million in 2015 when sold to farmers as finished apple trees. These new rootstocks are being adopted by farm operations ranging from small pick-your-own operations to large fruit farms.