'—■"'n "TT' .'~TT*-"*'^T"r1* 



17 



or a feeding deterent in the squares that varied in concentration among the 

 lines of cotton tested. 



27. ; Maxv^ell, F. G.; and Jenkins, J. N. 1969. Influence of changes in 

 the cotton plant during the season on the feeding, oviposition, and 

 development of the boll weevil. J. Econ. Entomol. 62: 239-2A2. 



Two varieties of cotton ( Gossypium hirsutum L.), Deltapine Smooth Leaf (DPSL) 

 and Acala 4-42-77, were studied 2 years to determine whether changes in the 

 plant during the growing season might affect feeding, oviposition, and 

 development of the boll weevil, Anthonomus grandis Boheman. The criteria 

 used to measure the effects were the tests for antibiosis, feeding stimulant, 

 and oviposition normally used to study host-plant resistance. The overall 

 averaged results for 2 seasons showed no differences between varieties, but 

 there were significant differences within test periods. This interaction 

 between variety x test period indicated that testing is necessary through 

 several periods of a season to determine true differences among varieties. 

 In the test of feeding stimulants, the difference between squares collected 

 at different dates was significant only after August 24, probably because there 

 was less feeding on samples collected August 31 and September 7; the diffe- 

 rence between varieties was not significant. In the studies of antibiosis 

 made with lyophilized square powder diets there were no significant differences 

 in time to eclosion of adults and vreight of emerging weevils for samples 

 collected weekly; thus, the time of the season that squares are collected 

 should not affect results of a test of antibiosis. 



28. ; Maxwell, F. G.; and Jenkins, J. N. 1972. Seasonal fluctuations in 

 oviposition of the boll weevil in the laboratory. J. Kans. Entomol. 

 Soc. 45: 242-254. 



Oviposition of boll weevils, Anthonomus grandis Boheman, fed standard adult 



.,X 



