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Crop phenology is very important in regular crop monitoring. Generally, phenology is monitored through field observation surveys or satellite data. The relationships between ground observations and remotely sensed derived phenological data can enable near-real-time monitoring over large areas, which has never been attempted on hazelnuts. In this study, we extracted phenological metrics derived from MODIS Enhanced Vegetation Index (EVI) in hazelnut production regions and compared them with the spring ground phenological data (BBCH scale) from orchards located in the same area of Turkey over the period from 2019 to 2022. We observed a specific temporal dynamic between remote sensing phenometrics and ground observations. The metrics Greenup, Upturning Date, and Threshold 20% metrics corresponded to the early of EVI growth and were synchronous with the female flowering of hazelnut and ending before bud break. The metrics Threshold 50% and Start of season were associated with the steepest portion of the EVI curve, i.e., canopy greening and thickening, and occurred between ovaries enlargement and leaves unfolding. The metrics Peak of Season, Stabilization Date, and Maturity corresponded to the end of spring vegetative growth. The main outcomes are that (i) female flowering occurred before 20% of vegetation development (BBCH 64P occurred about one month before Threshold 20%), (ii) phenometrics from satellite remote sensing (i.e., Upturning Date and Threshold 20%) well-reflected leaf emergence (r s = 0.30 and r s = 0.32, respectively; p < 0.05) and unfolding (r s = 0.35 and r s = 0.39, respectively; p < 0.05), and (iii) cluster appearance temporally aligned with the peak of the EVI curve (Stabilization Date and BBCH 71P differed by around 4 days). Our method is transferable to operational phenology monitoring, and future applications will consider the senescence season and the effect of environmental variability on the comprehension of vegetation dynamics., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

China possesses a copious and geographically diverse reservoir of hazel (Corylus spp.) resources, albeit scholarly endeavors focusing on the selection and domestication of indigenous wild hazelnut strains remain scant. To develop and utilize high-quality wild hazelnut resources, this study selected eight populations of wild hazelnuts from seven different provenances in Heilongjiang Province, China. Natural hybrid seeds of eight populations were sown in the Chohai Forest Farm in Longjiang County, Heilongjiang Province, in 2018. In April 2020, two-year-old seedlings were used to establish a provenance trial forest, thereby initiating the provenance trial. Growth parameters were measured using electronic calipers, and pollen characteristics were observed under an electron microscope. The trials meticulously explored the trees' flowering biology, growth parameters, and the economic attributes of the produced nuts. Principal component analysis was employed to comprehensively assess differences among the wild hazelnut populations from various provenances, aiming to identify superior wild hazelnut provenances. The results unveiled significant geographical variations among the tested provenances across several facets: the flowering period of male blossoms extended from April 2nd to April 19th, while female flowering occurred within the timeframe of April 2nd to April 22nd. Moreover, pollen grain morphology demonstrated variability, with the polar axis ranging from 14.02 to 17.09 micrometers, the equatorial axis spanning 16.02 to 18.75 micrometers, and the ratio of polar to equatorial axes fluctuating between 0.88 and 0.92. Through correlation analyses, nut length emerged as a pivotal determinant significantly influencing both kernel weight and the hundred-grain weight. A principal component analysis (PCA) further consolidated these findings, selecting the Nehe-originated variegated Corylus heterophylla as the superior provenance based on a comprehensive evaluation of its combined traits. This study constitutes a seminal contribution to the hazelnut breeding endeavor in China, establishing a robust foundation for informed cultivation strategies geared towards optimizing both the yield and the quality of hazelnut resources, thereby advancing the understanding and exploitation of China's wild hazelnut biodiversity., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Yuan et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Cultivation studies evaluating land-use histories and coevolutionary dynamics between humans and plants focus predominantly on domesticated species. Traditional anthropological divisions of "foragers" and "farmers" have shaped our understanding of ancient cultivation practices but have several limitations, including how people stewarded and managed nondomesticated species. To investigate the long-term effects of plant management in the Pacific Northwest, this study focuses on beaked hazelnut ( Corylus cornuta ) which has a long, precolonial history of management, transportation, and cultivation in British Columbia (BC, Canada). In particular, isolated hazelnut populations in northwestern BC are thought to be the result of historical transplanting and management. We sampled individual hazelnuts (n = 219) representing three distinct regions in and assessed 9,650 genome-wide SNPs identified with nextRAD genotyping-by-sequencing libraries to test for population genetic structure. We used linear measurements of individuals to assess morphological phenotypes and to identify variation between individuals and lineages. These data reveal shared genetic clusters in distant and disjunct northwestern and interior regions consistent with the movement of humans across the landscape. We also find several small genetically distinct populations in the northwestern region. The Genetic structure of hazelnut in the previously labeled "disjunct" region in Gitxsan, Ts'msyen, and Nis g a'a homelands is consistent with the enduring influence of people on the distribution of purportedly "wild" plant species. Our results support the hypothesis that hazelnut was likely transplanted long distances and also managed in situ. This study highlights the often-overlooked agency of Indigenous Peoples in shaping species range distributions in North America., Competing Interests: Competing interests statement:The authors declare no competing interest.

Hazelnuts are traditional woody oilseed plants. Corylus L. resources are rich in variety and widely distributed in China. However, the identification of germplasm varieties and the selection of superior varieties remain quite limited. This study aimed to analyze the genetic diversity of 331 Corylus L. germplasms using 16 simple sequence repeat (SSR) markers. Based on this, 11 pairs of core primers were selected, a fingerprint database of germplasm resources was constructed, and a primary core collection was screened. The results indicated that these tested Corylus L. germplasms exhibited a high level of genetic diversity, with an average number of alleles (Na) per locus of 14.5 and a polymorphic information content of 0.777. The phylogenetic relationships among various hazelnut cultivars were characterized by complexity, and they were delineated into four distinct groups facilitated by genetic distance analyses. An SSR fingerprint database for 331 Corylus L. germplasms was successfully constructed using the 11 obtained core SSR markers to increase the discrimination efficiency. Ultimately, 127 primary core accessions of Corylus L. were selected. The retention rate for the observed Na and MAF (the minor allele frequency) in the primary core germplasm constructed based on a sampling proportion of 38.36% was 100% and 94.7%, respectively. Shannon's information index (I) was highly consistent between the core and original germplasms, indicating that the core germplasm could fully represent the genetic diversity of the original germplasm. Additionally, the principal coordinate analysis of the selected primary core germplasm was essentially consistent with that of the entire original germplasm, further supporting the broad representativeness of the core germplasm. This study provided a basis for precisely identifying and efficiently utilizing Corylus L. accession., Competing Interests: NO authors have competing interests., (Copyright: © 2024 Yang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)