536 



Journal of A\^ricnHiirc , Victoria [lo Sept., 1912. 



PROPAGATION OF FRUIT TREES. 



{Coiifi lined frt'in pa^c ■\^<^-) 



C. F. Cole. Orchard Supervisor. 



Fungus Diseases. 



Fungi, like mosses, are a low form of i)lant life. They belong to the 

 great cryptogamir grouj), which includes phmts that are flowerless and 



' hence do not produce 

 seed. In fungi, pro- 

 pagation is l)v si)ores of 

 various kinds. 



Fungi live on the 

 substance of other 

 l)lants. Some draw 

 their nourishment from 

 li\ing plants (parasites). 

 Some live on dead 

 phmt substance (sapro- 

 ])hvtes). When a para- 

 site can live for a time 

 on dead plant tissue it 

 is called a facultative 

 saprophyte. This pro- 

 pertv is of importance 

 in securing the survival 

 at times of parasitic 

 infection. 



An attack by plant 

 fungus differs from an 

 attack bv in.sect life in 

 the following particu- 

 lars : — (jenerally with 

 insects the attack is 

 gradual and may be 

 noticed from the earli- 

 est stages. The serious- 

 ness of an attack is 

 generally controlled by 

 the rapidity with Avhich 

 they perpetuate their 

 kind. But with most of the fungi, their presence is not observable until the 

 harm is actuallv done. It is thus specially incumbent upon growers to 

 applv a suitable fungicide at a time which will prevent the spores from 

 germinating, and so destroy the fungus in its early .stages of growth. 



The germination of spores and the growth of fungi attacking fruit trees 

 is largely controlled and influenced by the climatic conditions prevailing at 

 the season suitable for their development. During a phenomenally wet 

 spring, summer, or autumn, some species of fungi cause considerable 

 damage that, in normal seasons, would do little or no harm. Dry weather 

 conditions are adverse to their growth, whilst damp .soil, bad drainage, 

 excessive irrigation, and a moist, humid atmosphere are all favorable. 



FIG. 7--- 



-PEACH BUD ATTACKED BY LEAF 

 CURL FUNGUS. 



