Table 1. Effects of Multiple Applications of a Systemic Insecticide
on Grain Yield (bu/A) of Susceptible and Resistant Wheat Varieties
Grown in a Field at Marianna, Florida Heavily Infested by the Hessian
Fly (1990).


 GRAIN YIELD (bu/A)
UNTREATED FALL TRT. FALL & SPR FALL & 2 SPRING


VARIETY


FLORIDA 301 45.2 d-f# 51.2 b-d


FLORIDA 301H*

FLORIDA 302


49.6 b-e


20.3 h


FL85363-G18-14* 52.1 b-d

FLORIDA 303 40.5 e-g


COKER 9766*


62.0 a


45.2 d-f


35.7 g


48.3 c-f


50.6 b-d


61.8 a


53.5 a-d

50.3 b-d

39.5 fg

47.5 d-f

58.6 ab

58.8 ab


53.3 a-d


40.6 e-g


57.8 a-c


*variety containing genetic source of resistance to the Hessian fly.
#values with the same letter are not significantly different for
 Duncan's Multiple Range Test (Alpha = .05) (SAS INST, 1991).


 Table 2. Effects of Multiple Applications of a Systemic Insecticide
 on Test Weight (lb/bu) of Susceptible and Resistant Wheat Varieties
 Grown in a Field at Marianna, Florida Heavily Infested with the
 Hessian Fly (1990).


 TEST WEIGHT (Ib/bu)
VARIETY UNTREATED FALL TRT. FALL & SPR FALL & 2 SPRING


FLORIDA 301 56.2 b-d# 56.5 a-c 56.5 a-c 56.4 a-d

FLORIDA 301H* 56.6 a-c 56.3 b-d 56.8 ab --

FLORIDA 302 53.9 i 54.8 gh 54.5 hi 55.0 f-h

FL85363-G18-14* 55.9 b-e 55.4 d-g 55.7 c-f --

FLORIDA 303 55.3 e-h 56.7 ab 57.1 a 57.1 a

COKER 9766* 56.6 ab 56.4 a-c 56.4 a-c --


*variety containing genetic source of resistance to the Hessian fly.
#values with the same letter are not significantly different for
Duncan's Multiple Range Test (Alpha = .05) (SAS INST, 1991).