80 CONTENTS 13.1 Introduction 13.2 Eucalyptus diseases (gum) 13.3 Acacia diseases (wattle) 13.4 Pinus diseases (pine) 13.1 Introduction This chapter deals only with the major diseases of commercial forestry trees in South Africa.0 CONTENTS 13.1 Introduction 13.2 Eucalyptus diseases (gum) 13.3 Acacia diseases (wattle) 13.4 Pinus diseases (pine) 13.1 Introduction This chapter deals only with the major diseases of commercial forestry trees in South Africa.
The pigment responsible for most light-harvesting by plants is chlorophyll, a green pigment. The green color indicates that it is absorbing all the non-green light-- the blues (~425-450 nm), the reds and yellows (600-700 nm).
Chlorophyll is the center of photosynthesis and makes plants green. Heme is responsible for carrying the oxygen in our blood, causing the red color. At the center of each molecule is a porphyrin ring. This beautiful and symmetrical structure is critical to function, binding a metal ion - magnesium in chlorophyll and iron in heme.