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Qualitative study examined development of psychosocial attributes- sense of belonging, science identity, and self-efficacy- among first-year life science undergraduate students who participated in integrated and culturally engaging research activities at a rural Hispanic Serving Institution (HSI). 

Abstract Severe and frequent heat and drought events challenge the survival and development of long-generation trees. In this study, we investigated the genomic basis of heat tolerance, water use efficiency, and growth by performing genome-wide association studies in coastal Douglas-fir (Pseudotsuga menziesii) and intervarietal (menziesii x glauca) hybrid seedlings. GWAS results identified 32 candidate genes involved in primary and secondary metabolism, abiotic stress and signaling, among other functions. Water use efficiency (inferred from carbon isotope discrimination), photosynthetic capacity (inferred from %N), height, and heat tolerance (inferred from electrolyte leakage in a heat stress experiment) were significantly different among Douglas-fir families and varieties. High elevation seed sources had increased water use efficiency, which could be a result of higher photosynthetic capacity. Similarly, families with greater heat tolerance also had higher water use efficiency and slower growth, suggesting a conservative growth strategy. Intervarietal hybrids showed increased heat tolerance (lower electrolyte leakage at 50 oC and 55 oC) and higher water use efficiency compared to coastal families, suggesting hybridization might be a source of pre-adapted alleles to warming climates and should be considered for large-scale reforestation projects under increasingly arid conditions. 

Mycorrhizal restoration benefits are widely acknowledged, yet factors underpinning this success remain unclear. To illuminate when natural regeneration might be sufficient, we investigated the degree mycorrhizal fungi would colonizePopulus fremontii(Fremont cottonwood) 2 years after the restoration of a riparian corridor, in the presence of an adjacent source. We compared colonization levels across plant populations and ecotypes, and from trees in the planted area to those in natural source populations. Four findings contribute to the theory and application of host–symbiont interactions. (1) Median ectomycorrhizal colonization of trees in the planted area was less than one‐tenth of that within natural source populations (p < 0.05), suggesting that even with adjacent intact habitat, sluggish regeneration would make proactive mycorrhizal restoration beneficial. (2) Within the planted area, median ectomycorrhizal and arbuscule colonization of trees sourced from greater distances were less than one‐third of that for trees sourced locally (p < 0.05), suggesting translocation poses barriers to symbioses. (3) Changes in colonization did not align with plant ecotypes, suggesting that geographic scales of selection for plants and fungi differ. (4) Slight increases in median mycorrhizal colonization (from 0% to 5%) were strongly correlated with increased survival for the plant provenance with lowest survival (r² = 46% andr_s = 48%,p < 0.05), suggesting mycorrhizae are particularly beneficial when plants are under stress (including translocation‐induced stress). This study is novel in demonstrating that mycorrhizal regeneration is slow even in the presence of adjacent intact habitat, and that when colonization could seem negligible, it may still have biological significance.