By 2100, climate change is predicted to warm high-latitude summers by 3–8 °C (ACIA 2005, Christensen et al. 2007). High temperatures will become more common in the boreal region and, in the absence of significantly increased precipitation, drought frequency and intensity will increase. Much of the North American boreal consists of forests dominated by black spruce (Picea mariana (Mill.) B.S.P.)...

Stressful parental environments can influence offspring size and development either adaptively or maladaptively, yet little is known about species' differences in this complex aspect of phenotypic plasticity. We performed a reciprocal split-brood experiment to compare transgenerational plasticity in response to drought stress in two closely related annual plant species. We raised inbred replica...

Holoparasites are nonphotosynthetic plants that acquire all resources from hosts. The holoparasite Cuscuta gronovii is native to much of the US with a broad host range including Verbesina alternifolia, an understory perennial. Both species grow in moderate to moist soils and occur in habitats that may experience prolonged or episodic drought. We applied the Wise-Abrahamson Limiting Resource Mod...

Plant roots may be linked by shared or common mycorrhizal networks (CMNs) that constitute pathways for the transfer of resources among plants. The potential for water transfer by such networks was examined by manipulating CMNs independently of plant roots in order to isolate the role(s) of ectomycorrhizal (EM) and arbuscular mycorrhizal fungal (AMF) networks in the plant water balance during dr...

Leaf water potential (') and leaf conductance (gl) were measured in the field in 20-year-old olive trees subjected to two treatments of soil water content (dry-farming and drip-irrigation). Differences between treatments of up to 0.35 MPa were observed in predawn , values. At midday, these differences were of up to 0.83 MPa. However, no significant differences between treatments were observed i...

Present study was conducted to investigate whether plant growth regulators viz. salicylic acid and ascorbic acid can alleviate the adverse effects of drought stress on germination and seedling growth of two sunflower hybrids (Hysun-33 and Hysun-38). Two (-0.06 MPa and -0.12 MPa) levels of drought stress were created by adding different concentrations of (PEG8000) polyethylene glycol in growth m...

The detrimental drought effects could be listed as the loss in dry weight and silicon is known to enhance crop tolerance to drought by increasing seedling growth and hydraulic conductivity. To investigate the effects of silicon priming (0, 1 and 2 mM as sodium silicate), on seedling growth and root anatomy of three barley cultivars (Khatam, Rihane, and Nimrooz) a laboratory experiment was condu...

Drought resistance and recovery ability are two important requisites for plant adaptation to drought environments. Proline (Pro) metabolism has been a major concern in plant drought tolerance. However, roles of Pro metabolism in plant recovery ability from severe drought stress are largely unexplored. Periploca sepium Bunge has gained increasing attention for its adaptation to dry environments....

Drought is one of the most important abiotic stresses affecting the productivity of maize. Previous studies have shown that expression of a mitogen-activated protein kinase kinase kinase (MAPKKK) gene activated an oxidative signal cascade and led to the tolerance of freezing, heat, and salinity stress in transgenic tobacco. To analyse the role of activation of oxidative stress signalling in imp...