The natural light conditions above the Arctic Circle are unique in terms of annual variation creating special growth for crop production. These include low solar elevations, very long daily photosynthetic periods, midnight sun/absence dark nights, and altered spectral distribution depending on elevation. All these factors known to affect metabolism plants, although their influence northern plan...

Tree densities have increased greatly in olive orchards over the last few decades. In many annual crop species, density reduces horizontal red/far-red (R/FR) and blue/green (B/G) ratios during canopy development even before direct shading occurs, such changes are known to alter plant morphology. This study with trees evaluated: (1) whether leaf area index (LAI) of neighboring modifies light qua...