A deep learning-integrated phenotyping pipeline for vascular bundle phenotypes and its application in evaluating sap flow in the maize stem

Plant vascular bundles are responsible for water and material transportation, and their quantitative and functional evaluation is desirable in plant research. At the single-plant level, the number, size, and distribution of vascular bundles vary widely, posing a challenge to automatically and accurately identifying and quantifying them. In this study, a deep learning-integrated phenotyping pipeline was developed to robustly and accurately detect vascular bundles in Computed Tomography(CT) images of stem internodes. Two semantic indicators were used to evaluate and identify a suitable feature extraction network for semantic segmentation models. The epidermis thickness of maize stem was evaluated for the first time and adjacent vascular bundles were improved using an adaptive watershed-based approach. The counting accuracy(R^(2)) of vascular bundles was 0.997 for all types of stem internodes, and the measured accuracy of size traits was over 0.98. Combining sap flow experiments, multiscale traits of vascular bundles were evaluated at the single-plant level, which provided an insight into the water use efficiency of the maize plant.

Climate change threats to protected plants of China: an evaluation based on species distribution modeling

Climate change poses major new challenges to biodiversity conservation. Distribution ranges of species have been proven to be affected by climate anomalies.Detecting the extent of protected species response to climate change can help formulate flexible conservation strategies to overcome the changing climate. Using species distribution modeling and high resolution climate data, we simulated current distribution patterns of 233 protected plants in China. Those patterns were then projected into future suitable habitats for each species under nine climate change scenarios, with no migration or full migration hypotheses. Under the most extreme climate change scenario(CGCM-B2a), we evaluated species extinction risks.Sixteen percent of protected plants are expected to lose more than 30 % of their current ranges. By calculating areal shifts, hotspots for emigrants, immigrants, and persistent species were identified under climate change.Flexible conservation strategies were addressed for thoseregions. Those strategies strongly depend on the migration types of species and sensitivity of the hotspots to changing climate. In hotspots for emigrants, the main conservation strategy is ex situ protection; protected species from these regions should be stored in seed banks or botanical gardens. For hotspots of immigrants, enough space should be maintained for new species, and some measures are necessary to assist dispersal. For hotspots of persistent species,more natural reserves are needed. We highlight related fields that can help conserve protected species in the future,such as conserving the soil seed bank and understanding of the effects of migration ability and interactions between protected species.