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).
We hypothesized that if green leaves have a significantly higher rate of photosynthesis (consumption of CO 2) than yellow leaves, because green leaves contain more green chlorophyll a and chlorophyll b photosynthetic pigments than yellow leaves, then the color of the leaves affects the rate of photosynthesis.