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NOTES ON A THRIPS INJURIOUS TO VINES IN CYPRUS. 



By Z. G. SoLOMiDES, 

 Entomologist to the Department of Agriculture^ Cyprus. 



This insect, which is being described by Mr. R. Bagnall under the name of Crypto- 

 thrips brevicollis, sp. n., has been known to vine-growers in Cyprus for at least ten 

 years, but was believed to be harmless, and the damage it actually effected was attri- 

 buted to other causes, e.g., fungus, unsuitable soil, bad cultivation, or faulty methods 

 of planting. A fortnight's study on the spot during August last convinced me that 

 the injury from which these vines were suffering was not due to any of these causes. 

 A careful examination of roots, leaves, branches, grapes and flowers revealed no 

 fungoid disease. Nor was the attack due to defective soil or imperfect planting or 

 cultivation, as the same characteristic attack was seen on the vines of the Depart- 

 mental Model Vineyard at Omodhos where the soils had been most thoroughly 

 cultivated and the vines had been carefully planted and skilfully tended. The vine 

 owners whose vines were found thus attacked called the disease " Caraoli," which 

 means " curling," a condition brought about by the action of the vine thrips. 



This insect has three generations, and between April and the middle of September 

 it attacks all the more tender parts of the vine. The eggs are laid in the buds or near 

 the base of the opening tender leaves. The larvae on hatching out attack these by 

 cutting or scraping the epidermis and sucking the juices. The buds are not wholly 

 destroyed and are often capable of developing, though not naturally, as the distances 

 between the joints of the stems are shortened and the leaves borne on them, as well 

 as those which are directly attacked, are curled and bear spots of varying sizes where 

 the under surface of the epidermis has been gnawed by the thrips. The nymphs 

 and adults continue to injure the foliage upon the branches where the attack is 

 localised, the plants meanwhile putting forth other branches. 



When the insects have completed the destruction in one place, they commence a 

 similar attack elsewhere. Some gnaw the petioles or stalks of leaves or buds, near 

 the base, checking their growth and causing curling. When they are numerous all 

 the first buds and small branches are nearly destroyed and fresh ones arc then formed. 

 By the time the insects have multiplied greatly and arrive on the fresh branches, 

 these latter have developed and only their most tender leaves are liable to be damaged. 



At the time of flowering the insects mate and lay eggs on the tendrils near the 

 flowers or on the leaves, and then begin their attack either on the flowers, the stamens 

 and pistils of which are destroyed, or on the newly set grapes. The injury, according 

 to my observations, is usually limited to two or three clusters. The others develop, 

 but are in turn attacked at a later stage. 



The mode of attack is as follows : — The insect scrapes or bites the skin of the grape ; 



it then dips its beak vertically into the pulp and absorbs the juices. If it is not 



satisfied with the spot chosen, it withdraws its beak and immediately attacks another 



part of the grape. I have observed that two minutes after a thrips has withdrawn 



(C177) H 



