CHAPTER VIII. 



DISEASES OF CITEUS TBEES. 



Aphides. The Green Fly (mava in Marathi). All kinds of Citrus 

 plants are liable to the severe attack of this pest. Young branches as they 

 develop are often infested with colonies of tiny black or yellow insects. 

 Such plants as a rale have an unhealthy appearance and the lower leaves 

 are covered with a sticky secretion. At first the insects are wingless and 

 have two short tubes projecting from the abdomen. Later on winged 

 individuals appear. These little insects do a considerable damage to citrus 

 plants by sucking juice from young branches and leaves; "they also 

 excrete a sweet liquid which falling on the leaves below makes them sticky 

 and shiny and gives a footing to a black fungus ; this appearance on the 

 plant is generally familiar in India. Ants and other insects are fond of this 

 liquid and come to the plants to obtain it. Ants obtain it direct from the 

 plant lice and it is well known that some ants use plant lice as we do cows, 

 not only ' milking ' them but preparing shelters for them and caring for 

 them " (Lefroy : Indian Insect Pests, page 138). 



The aphides are generally worse in the cold season, particularly in the 

 months of October to February. They hate a natural enemy which keeps 

 them in check, namely, the lady-bird-beetle which is a small rounded bettle 

 about the size of a split pea, coloured in red and yellow with black spots. 

 The grub and beetle feed very actively upon aphides. The best remedy is 

 to spray the plants particularly young parts with Incosoppl, a product 

 manufactured from cotton seed by the Indian Cotton Seed Oil Company of 

 Navasari, District Surat. This substance is mixed with cold water in the 

 proportion of 1 Ib. to 8 gallons of water. The disease will be checked with 

 two sprayings given at the right time j otherwise more sprayings at an 

 interval of one week will be necessary. 



Aphides can also be checked by spraying tobacco solution. " Soak 2 Ibs. 

 of tobacco in 2 gallons of water for 24 hours or boil for half an hour. 

 Disssolve | Ib. bar soap or 1 point of soft soap in the mixture. This is the 

 stock solution. Dilute with 7 parts of cold water." 



The Lemon cutter pillar (Papilio demoZetw). All kinds of Cirtus 

 trees and particularly Eagdi Limbu are defoliated by curiously marked 

 caterpallars which feed openly upon the leaves of the plant. These cater- 

 pillars hatch from small round yellow eggs laid a few at a time upon the 

 topmost shoots of the plants where the young caterpillars will find tender 

 leaves upon which to feed. They are at first brown with white markings 

 closely resembling the droppings of birds, and doubtless feed on the leaf in 

 an exposed position to assist the resemblance. When nearly full grown the 

 colour changes to a vivid green, with lateral brown markings and the 

 caterpillars now leave their exposed position on the leaf. When young they 

 feed on the quite small leaves, attacking larger leaves as they grow older. 

 As a rule only a few are found on each plant but they do much mischief to 

 small plants and, if abundant, entirely strip them. The caterpillar pupates 

 on the plant, fixing itself by the tail and by a thread round the body which 

 is fastened on each side to the plant. The butterfly is large and 

 conspicuous, common throughout the plains. It lays its eggs also on the 

 JBer (Ziiyphua jujuba) and other wild plants. 



