"Improving economic and environmental sustainability in tree fruit production through changes in rootstock use."
Welcome to the NC-140 Regional Rootstock Research Project. The goal of these pages is to disseminate research information generated by pome fruit rootstock research projects throughout North America that are part of the NC-140 Regional Research Project. Additionally, the site offers NC-140 researcher and administrative members enhanced collaboration and communication.
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TITLE: Rootstock and Interstem Effects on Pome and Stone Fruit Trees
OBJECTIVES:
- To evaluate the field performance of pome- and stone-fruit rootstocks in various environments and under different management systems, and to optimize experimental design for such evaluations.
- To assess and improve asexual propagation techniques of pome- and stone-fruit rootstocks.
- To develop improved pome- and stone-fruit rootstocks through breeding and genetic engineering, and to acquire new rootstocks from worldwide sources.
- To understand the developmental and abiotic stress physiology of rootstock/scion interactions in pome- and stone-fruit trees.
JUSTIFICATION
With the increasingly competitive international market, the growing demand for higher quality fruit by consumers, the strong pressure to reduce chemical use, and an ever increasing need to enhance the economic efficiency of production, tree-fruit growers must look to alternative economically and environmentally sustainable management strategies for production. Growers who want to stay profitable must establish high-density plantings with much smaller trees with new scion cultivars. These high-density plantings may cost several times more to establish than low-density plantings, thus greatly enhancing the economic risk. Rapid returns are also vital for providing the ability to change cultivars in response to market or genetic opportunities. The central component of high-density systems is the rootstock. The root system imparts many characteristics to the mature tree such as size, precocity, productivity, fruit quality, pest resistance, stress tolerance, and thus profitability.
As the industry moves from low- to high-density plantings, several rootstock-related problems must be addressed. New pome- and stone-fruit rootstocks cannot be recommended to commercial growers without reservations until there is sustained research as to soil and climatic adaptability, root anchorage, size control, precocity, productivity, pest resistance, and propagation ability. In general, field testing of rootstocks in an orchard setting requires a minimum of ten years to assess accurately the potential for improved profitability, reduction of inputs, and enhancement of production efficiency. With year-to-year variation in weather, this time span is necessary to obtain a true indication of rootstock performance.