\ l.«.l. I \i'.i I I R0P8. 715 



stage. It is advisable, before planting, to arrange a contract with some 

 pickle manufacturer, as otherwise it might prove difficult to place the pro- 

 duce when it is ready. 



The varieties that do best in this State are Apple-shaped (most suitable 

 for private gardens), Long Green Prickly, White Spine, and Commercial 

 (all popular in the Sydney vegetable market), Gherkins (a small variety 

 grown chiefly for pickle), Fordhook Pickling, and Small Green Prickly (both 

 good pickling sorts). 



Diseases of Cucurbitacese.* 



Pumpkin-leaf Oidium (Oidium sp.). 



Well known to all growers of pumpkins, squashes, and melon, is the white 

 and powdery or mealy fungus which blights the leaves, causing them to 

 turn first yellow, then brown, and finally to die. The fungus, which probably 

 belongs to the group of fungi known as Erysipheoe, or in other words the 

 Oidium group, is mostly external, like its relative the vine oidium. The 

 life-history of the fungus is imperfectly known as yet. 



Controls. — (1.) Where practicable, burn or otherwise destroy affected 

 material. Do not plough it in. 



(2.) Practise a rotation of crops. Do not grow pumpkins two years in 

 succession on the same land. When possible, put them on new land. 



(3.) This disease has been combated with entire success by using flowers 

 of sulphur, as for oidium of the vine. It is necessary to be particularly 

 careful to hit the lower surface of the leaves. 



(4.) Bordeaux mixture is often beneficial when applied as a spray. 



Anthracnose of Pumpkin. 



Anthracnose attacks pumpkins, marrow, squash, water-melon, and rock 

 melon. The seriousness of the attack depends on the weather, hot, moist 

 conditions favouring the disease. 



The cause of the disease is a fungus, Gloeosporium sp. It attacks all 

 parts of the plant except the root. On the stems it causes water-soaked 

 spots, which turn brown and become depressed and cracked; on the leaves, 

 circular dark spots are developed which become so numerous as to involve 

 the entire leaf, which crinkles and has the appearance of having been burned 

 by fire; on the fruit, anthracnose is manifested on the rind as circular 

 depressions which become covered with a salmon or pink coloured coat made 

 up of the spores of the fungus. 



The disease may become serious on land where pumpkins or other sus- 

 ceptible crops are grown successively for a period of years, and spreads 

 rapidly during transit. 



For the control of this disease a rotation of crops should be practiced. A 

 three-year rotation, excepting the susceptible crops, should prevent the 

 disease from gaining a foothold. Diseased vines should not be ploughed 

 under or allowed to lie about the field, but collected and burnt. 



* Compiled by Officers of the Biological Branch. 



