Awards issued prior to january 20, 2025, were funded under previous administrations and may not reflect the priorities and policies of the current administration.** most fruit and nut crops in the…

Awards issued prior to january 20, 2025, were funded under previous administrations and may not reflect the priorities and policies of the current administration.** most fruit and nut crops in the U.S. Are propagated as clones and grafted onto rootstocks. This process depends on rootstocks being able to form new, or adventitious, roots. The pear industry has a high demand for new rootstock cultivars that can offer dwarfing and disease resistance, as well as material that is virus free, all of which is especially important as climate change progresses and disease and resource-use become more pressing issues. When new cultivars are developed to meet these needs, nurseries need to develop cost-effective protocols to produce plants for growers. However, pears are well known for being difficult to root. While protocols have been published for rooting pears, these are largely focused on a few specific cultivars, and pear cultivars vary widely in their responses to different rooting treatments. The proposed work aims to improve rooting predictability by understanding changes in gene expression (using transcriptomics) and hormone localization and signaling (using quantification and sensors) between cultivars in response to rooting treatments. By establishing protocols and tools to compare gene expression and hormone responses between hard-to-root and easier-to-root cultivars, this work seeks to identify genes and molecular patterns associated with successful rooting, as well as lay the groundwork for understanding other hormone-related phenotypes and processes in pears. The proposed work addresses priorities withing the physiology of agricultural plants program area through improvement to plant production and propagation and improvement of a fundamental step in producing and releasing new varieties that may be developed for combating climate challenges.