Introducing a sensor to measure budburst and its environmental drivers

This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Frontiers Research Foundation. The published article can be found at: http://www.frontiersin.org/Plant_Science.Budburst is a key adaptive trait that can help us understand how plants respond to a changing\ud climate from the molecular to landscape scale. Despite this, acquisition of budburst\ud data is constrained by a lack of information at the plant scale on the environmental stimuli\ud associated with the release of bud dormancy. Additionally, to date, little effort has been\ud devoted to phenotyping plants in natural populations due to the challenge of accounting for\ud the effect of environmental variation. Nonetheless, natural selection operates on natural\ud populations, and investigation of adaptive phenotypes in situ is warranted and can validate\ud results from controlled laboratory experiments. To identify genomic effects on individual\ud plant phenotypes in nature, environmental drivers must be concurrently measured, and\ud characterized. Here, we designed and evaluated a sensor to meet these requirements for\ud temperate woody plants. It was designed for use on a tree branch to measure the timing\ud of budburst together with its key environmental drivers; temperature, and photoperiod.\ud Specifically, we evaluated the sensor through independent corroboration with time-lapse\ud photography and a suite of environmental sampling instruments.We also tested whether\ud the presence of the device on a branch influenced the timing of budburst. Our results\ud indicated the following: the temperatures measured by the budburst sensor’s digital\ud thermometer closely approximated the temperatures measured using a thermocouple\ud touching plant tissue; the photoperiod detector measured ambient light with the same\ud accuracy as did time lapse photography; the budburst sensor accurately detected the\ud timing of budburst; and the sensor itself did not influence the budburst timing of Populus\ud clones. Among other potential applications, future use of the sensor may provide plant\ud phenotyping at the landscape level for integration with landscape genomics