tailieunhanh - Interactive effects of seed size and drought stress on growth and allocation of Quercus brantii Lindl. seedlings from two provenances

Quercus brantii is an important tree species in Zagros forests. Summer drought imposes severe limitations in Q. brantii forests, making reforestation with this species in general very difficult. This is further complicated by the limited ecophysiological information or this species. | Turkish Journal of Agriculture and Forestry Research Article Turk J Agric For (2013) 37: 361-368 © TÜBİTAK doi: Interactive effects of seed size and drought stress on growth and allocation of Quercus brantii Lindl. seedlings from two provenances 1, 1 1 2 Roghayeh ZOLFAGHARI *, Payam FAYYAZ , Mona NAZARI , Fernando VALLADARES 1 Department of Forestry, Agriculture Faculty, Yasouj University, 31875-5765 Yasouj, Iran 2 Museo Nacional de Ciencias Naturales, Spanish National Research Council (CSIC), 28006 Madrid, Spain Received: Accepted: Published Online: Printed: Abstract: Quercus brantii is an important tree species in Zagros forests. Summer drought imposes severe limitations in Q. brantii forests, making reforestation with this species in general very difficult. This is further complicated by the limited ecophysiological information for this species. To improve our understanding of factors affecting the drought tolerance of Q. brantii at early critical life stages, we explored the influence of seed size and provenance on growth and survival of Q. brantii seedlings under drought. As expected, drought reduced growth and survival and increased the root-to-shoot ratio, with larger acorns rendering more vigorous growth than small ones. There was a positive correlation between seed size and root-to-shoot ratio under severe drought stress only for the provenance from the wetter region. Our results indicate that large seeds of Q. brantii from populations with good genetic material can render restoration programs in the Zagros forests more successful. Key words: Maternal environmental, Mediterranean forests, reforestation, root-to-shoot ratio 1. Introduction The seedling stage is an important, often critical, phase in the regeneration of woody species under natural conditions; the risk of lethal environmental stress is high at this stage. Water availability .