PARA RUBBER. 147 



session of their foliage for about 50 out^of every 52 weeks each year, 

 and to assume that the leaves, owing to their deciduous character , are 

 not likely to contract a permanent disease is by no means sound. 



Fungi. — Leaves of Para rubber seedlings and of older plants have 

 been attacked by a species of Eelminthosporium ;* the leaves 

 were " studded with circular, semi-transparent spots, each surround- 

 ed by a brown cushion from which arose the threads of the fungus." 

 It was suggested that the spots were due to punctures by insects and 

 the fungus grew on the dead tissue. Damaged parts of the leaves 

 of Para seedlings are also subject to the attacks of Periconia 

 pycnospora,f and species of Cladosporium and Macros porium. 



A species of Pestalozzia — identical with that which is associated 

 with the "grey Blight" on tea leaves — has also been found by 

 Petch on leaves of nursery seedings of Hevea, and according to that 

 mycologist were probably infected by wind-blown spores from the 

 adjacent tea. The fungus produces white irregular areas spreading 

 generally from the tip of the leaf. In the Straitsj the leaves of the 

 Para rubber seedlings have been attacked by a fungus, regarding 

 which Mr. Massee reported: " The pale blotches on the leaves are 

 caused by some species of Cercospora, but the absence of fruit pre- 

 vents specific identification." Ridley states thai this leaf fungus 

 is common all over the Malay Peninsula, but that except in the case 

 of seedlings does not do much harm. 



Petch has recently found a species of Gloeosporium on the leaves 

 of seedlings ; the fungus forms light brown spots on the upper sur- 

 face of the leaves, and finally the latter turn yellow and fall. 



It is satisfactory to know that, up to the present time, the leaves 

 of mature Para rubber trees are practically free from parasitic fungi, 

 but the disease on the leaves of seedlings is one which leads to partial 

 defoliation and checks the growth of the young plants. In all such 

 cases the diseased leaves should be pulled off and burnt and the rest 

 of the plants sprayed with Bordeaux mixture ; this consists of 6 lb. 

 of copper sulphate and 4 lb. of freshly- slaked burnt lime in 45 to 50 

 gallons of water. 



Insects. — According to Green:j: the leaves of Hevea are reported to 

 have been punctured by certain plant-sucking bugs, the most likely 

 species being Leptocorisa acuta and Riptortus linearis ; the former is 

 known as the "Rice-sapper." It appears that these pests puncture 

 the leaves and stems. " The injured leaves show numerous small 

 spots, each bordered by an irregular dark rim. within which the 

 tissues have dried and turned white." It is believed that the injury 

 to the leaves is due more to a fungus than to an insect. 



A scale bug — Lecanium nigrum, Nietn. — has also been observed by 

 Green on the leaves of young Para trees, but this can be easily 

 destroyed by means of Macdougal's mixture. The tips of seedlings 



* T. Petch. Mycologies] Notes, Tropical Agriculturist, June, 1905. 

 t Agriculturist Bui. of the Straits and K.M.S.. July. 1905. 

 % E. E. Green, Entomological Notes, Tropical Agriculturist, April 

 and May, 1905. 



