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Summary: Global warming is advancing the timing of spring leaf‐out in temperate and boreal plants, affecting biological interactions and global biogeochemical cycles. However, spatial variation in spring phenological responsiveness to climate change within species remains poorly understood.Here, we investigated variation in the responsiveness of spring phenology to temperature (RSP; days to leaf‐out at a given temperature) in 2754 Ginkgo biloba twigs of trees distributed across subtropical and temperate regions in China from 24°N to 44°N.We found a nonlinear effect of mean annual temperature on spatial variation in RSP, with the highest response rate at c. 12°C and lower response rates at warmer or colder temperatures due to declines in winter chilling accumulation. We then predicted the spatial maxima in RSP under current and future climate scenarios, and found that trees are currently most responsive in central China, which corresponds to the species' main distribution area. Under a high‐emission scenario, we predict a 4‐degree latitude shift in the responsiveness maximum toward higher latitudes over the rest of the century.The identification of the nonlinear responsiveness of spring phenology to climate gradients and the spatial shifts in phenological responsiveness expected under climate change represent new mechanistic insights that can inform models of spring phenology and ecosystem functioning. [ABSTRACT FROM AUTHOR]

This account presents information on all aspects of the biology of Ginkgo biloba L. (Ginkgo, Maidenhair tree) that are relevant to understanding its ecological characteristics. The main topics are presented within the standard framework of the International Biological Flora: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, reproductive and seed characters, herbivores and disease, history, conservation and global heterogeneity.Globally, Ginkgo survives a wide range of mean annual temperature (−3.3 to 23.3°C) and annual precipitation (34–3925 mm) conditions, according to a meta‐analysis. It prefers a warm, humid, open‐canopy and a well‐drained environment. The species shows strong tolerance to drought, freezing, fire, air pollution, heavy metals and low‐level salt, whereas it is intolerant to long‐time shade and waterlogging. Six Ginkgo trees even survived the atom bomb in Hiroshima, Japan, during World War II.Ginkgo is susceptible to few diseases. Those occurring in nursery seedlings and juvenile trees involve stem rot and leaf blight. The former is caused by Macrophomina phaseoli, which could lead to a mortality rate of 5%–12% (up to 31.8%) for seedlings. This disease can be mitigated by a 4‐h shading treatment and applying organic fertilisers. The pathogens inducing leaf blight include Alternaria alternata, Colletotrichum gloeosporioides and Pestalotia ginkgo, which may infect 100% juvenile trees in some regions. The application of 45% carbendazim or 50% Tuzet can effectively prevent leaf blight.Ginkgo biloba is one of the world's most distinctive trees with an important position in plant evolution and human society. It is a tall deciduous dioecious tree native to China. Refugial populations were identified in three glacial refugia located in eastern, southern and south‐western China, respectively, with a patchy distribution pattern and a small population size. It typically grows along flood‐disturbed streamsides in warm‐temperate deciduous (and evergreen mixed) broadleaved forests. Ginkgo may have been introduced repeatedly out of China since the sixth century. It has been planted as a landscape tree world‐wide, except in Antarctica. Ginkgo is also of great value for edible nuts, herbal medicine, religion and art. It is a natural and cultural symbol of China. [ABSTRACT FROM AUTHOR]

• Leaf unfolding of male and female ginkgo responses similarly to climate. • Long photoperiod significantly shortened the time to leaf unfolding. • Effects of temperature and photoperiod on leaf unfolding decreased along elevations. Climate change substantially affects plant phenology, resulting in earlier vegetation onset across temperate and boreal regions. Phenological shifts caused by warming may alter species interactions across trophic levels because of species-specific responses, and influence the reproductive success of dioecious species if the phenological sensitivity to warming (S T) differs between genders. We used twigs collected from male and female gingko trees at three elevations on Tianmu Mountain in eastern China. The twigs were cultivated in climate chambers to determine the effects of three temperatures (10, 15, and 20 °C) and two photoperiods (8 and 16 h). We observed slightly earlier leaf unfolding dates in male twigs (1 day), and a higher heat requirement (growing degree hours) for leaf unfolding in female (14,334 ± 588 °C) compared to male twigs (13,874 ± 551 °C). Similar responses to temperature (S T = 3.7 days °C−1), photoperiod and elevation were observed across genders. The long photoperiod treatment shortened the time to leaf unfolding by 9.1 days, but temperature and photoperiod effects on leaf unfolding differed significantly depending on the elevation of the donor trees. Specifically, S T was higher (4.17 days °C−1) and the photoperiod effect on S T was larger (decreased by 1.15 days °C−1) at the lowest elevation than at the higher elevations (S T = 3.26 days °C−1; decreased by 0.48 days °C−1). This may be related to environment-induced local adaptations and self-protection mechanisms of trees at high elevations to avoid frost damage. Our results indicate that the photoperiod and genetic adaptations to local environments influenced the warming-induced phenological responses in ginkgo, but these responses were generally similar between the genders. For a given species, individuals in different climates may exhibit different phenological responses to higher temperatures, with individuals in warmer regions likely becoming increasingly limited by the photoperiod as the climate warms further. [ABSTRACT FROM AUTHOR]

Abstract: Quercetin''s protective effects on the glomerulosclerosis of diabetic nephropathy (DN) in rat mesangial cells were investigated. The cell cycles, type IV collagen and laminin, TGF-β1 mRNA, Smad 2/3 and Smad 7, and activities of cell antioxidases were measured. Compared with the high glucose group, quercetin may decrease the cell percentages of G0/G1 phase, Smad 2/3 expression, laminin and type IV collagen, and TGF-β1 mRNA level significantly. The antioxidant capacity, the cell percentages of S phase and Smad 7 expression was significantly increased by quercetin. These results suggest that quercetin is a protective agent against glomerulosclerosis in DN. [Copyright &y& Elsevier]