EFFECTS OF ANTS ON THE PHYSIOLOGY AND DEVELOPMENT 

 OF APHIDS 



Влияние муравьев на поведение и размножение тлей 



С. J. BANKS 



(Rothamsted Experimental Station, Harpenden, England) 



The associations of ants Avith aphids have interested biologists for a long 

 time, but there has been a renewal of interest recently because the study 

 of these associations has thrown considerable light on the behaviour, develop- 

 ment and physiology of aphids. 



My starting point is the лл'огк of Herzig (1937) who found that Aphis fabae 

 Scop, attended by Lasius fuliginosus (Latreille), and A. sambuci L., 

 attended by L. niger L., each excreted more honeydew than when unattended, 

 and assumed that the attended aphids therefore absorbed more plant sap. 

 He further assumed that the supposed increase in feeding was the cause 

 of the observed increase in multiplication of ant-attended aphids on a bean 

 plot and said tliat the stimulation of feeding could double or treble aphid 

 numbers. He did not exclude the aphid's insect enemies from the plots, so that 

 the difference in numbers of the aphids which he reported could have been 

 caused by greater prédation of the ant-free aphids. Nixon (1951) reviewed 

 the literature on associations of ants with aphids and coccids and emphasised 

 that there is sometimes a complex and intimate interrelationship betлveen 

 the ant and sap-feeder, but that the association isoften casual and that both 

 partners do not necessarily benefit. He thought that the protective effects 

 of ants had been much exaggerated. 



There was considerable doubt, therefore, whether ant-attendance really 

 stimulates aphid feeding, Avhether there is a real increase in the aphid's repro- 

 duction rate and whether the ants give them any significant protection from 

 predators. 



Theexperimentsof El-Ziady and Kennedy (1956) indicated that A. fabae 

 Scop, multiply more rapidly when attended by L. niger L. whether the aphid's 

 enemies are present or not. They concluded that both aphid and ant benefit 

 nutritionally from their association, which is therefore a truly symbiotic one; 

 like Herzig, they thought that although there is some protection of the aphids 

 by the ants, it is of secondary importance compared with the increase of the 

 aphids' reproduction. They also showed, for the first time, that ant-attendance 

 delays the appearance of winged forms in aphid colonies and that, in some way, 



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