Glenn Wiygul

Localization of Pheromone in Male Boll Weevils Anthonomus grandis

these may represent separate species, Xestia adela Franclemont and X. adela Franclemont. Based on known geographical distribution of these forms we expect that only X. adela is present in our area (A. Hudson, pers. comm.). We thank S. J. Peesker, V. J. Gerwing and G. Beckett for technical assistance; and Dr. Anne Hudson (Biosystematics Research Institute, Agriculture Canada, Ottawa) for taxonomic advice. NRCC No. 19883.

Effect of juvenile hormone III and beta-bisabolol on pheromone production in fat bodies from male boll weevils, Anthonomus grandis Boheman (Coleoptera: Curculionidae).

Abstract 1. 1. Fat bodies form 1 to 10-day-old male boll weevils were treated with juvenile hormone III, beta-bisabolol, and juvenile hormone + beta-bisabolol. 2. 2. We measured the amount of sex pheromone produced after 2 hr of incubation with the above compounds. 3. 3. More pheromone was produced by the juvenile hormone III + beta-bisabolol treatment than by the others.

The effect of glucose and ATP on sex pheromone production in fat bodies from male boll weevils Anthonomus grandis boheman (Coleoptera: Curculionidae)

Abstract 1. 1. Glucose, added to fat bodies from adult male boll weevils ( Anthonomus grandis Boheman) incubated in saline solution, caused an increase in sex pheromone production in this tissue. 2. 2. ATP added to fat bodies from the same population of insects incubated in saline solution also caused an increase in sex pheromone production. 3. 3. This study proved our hypothesis that added energy sources can cause increased sex pheromone production in incubating male boll weevil fat bodies.

A comparison of certain aspects of nitrogen metabolism in non-diapausing and diapausing boll weevils, Anthonomus grandis

Abstract Both DNA and RNA were lower in males and females of a diapausing strain of boll weevils, Anthonomus grandis 10 to 15 days after emergence than in newly-emerged insects of the same strain. Protein content remained relatively constant in the strain of diapausing weevils, but increased substantially in the 10 to 15-day boll weevils of a non-diapausing strain; the relationship of lipoprotein to protein generally remained about the same in both strains for weevils of different ages of the same strain. Since the RNA-DNA ratios differed materially only in the 10 to 15-day diapausing males (2.2), it might be used as a corroborative indicator of diapause. The hypothesis that the boll weevil stores nitrogen as uric acid during diapause was disproven; rather the amount of stored uric acid diminished at the onset of diapause.

The effect of a heat-stable enterotoxin isolated from Escherichia coli on pheromone production in fat bodies isolated from male boll weevils

The effect of bacteria and bacterial products on mass reared insects has been a subject of continuing interest to those involved in studies using these insects. For those of us involved in cotton insects research, the bacterial contamination problems encountered in attempting to mass rear the cotton boll weevil (Anthonomus grandis Boheman) have been particularly difficult. Such contamination has been shown to reduce production of boll weevil sex pheromone (Gueldner et al., 1977), amino acids (Thompson & Sikorowski, 1978), fatty acids (Thompson et al., 1977), and oxygen uptake (Wiygul & Sikorowski, 1981). These studies indicate a direct effect by bacteria on the metabolism of boll weevils. In an earlier study, Wiygul and Sikorowski (1986) determined that Staphylococcal enterotoxin B, isolated from Staphylococcus aureus Rosenbach (family Micrococcaceae), inhibited pheromone production by male boll weevil fat bodies incubated in vitro using the method of Wiygul et al. (1982). Escherichia coli (Migula) Castellani and Chalmers (family Enterobacteriaceae) is another species of bacteria isolated from boll weevils (McLaughlin & Sikorowski, 1978), and known to produce enterotoxins. Enterotoxigenic E. coli are known to produce two types of enterotoxins (Banwell & Sherr, 1973) which affect humans and other mammals. One is heat-labile toxin that produces effects similar to the cholera toxin. The other is a heat-stable toxin with reported molecular weights of 1972 (Staples et al., 1980) and ca. 4000 (Takeda et al., 1979). The increased fluid secretion caused by the heat-stable toxin in mammals was reported to be associated with increased cyclic guanine monophosphate (GMP) but not cyclic adenosine monophosphate concentration (Gianella & Drake, 1979). Field etal. (1978) found that this increase in cyclic GMP production was caused by activation of guanylate cyclase rather than inhibition of cyclic GMP phosphodiesterase. There was no previous information on the effect of enterotoxins on cotton boll weevils. Sikorowski (1984) found that contamination by E. coli reduced adult boll weevil emergence by close to 50~o when these insects were reared in petri plates. In the present study, we measured the effect of a heat-stable enterotoxin isolated from E. coli on pheromone production in adult male boll weevils.

Oxygen uptake in male and female boll weevils, Anthonomus grandis boheman (Coleoptera: Curculionidae) of the ebony strain fed cotton squares (buds)☆

Abstract 1. 1. Oxygen uptake was measured in 1- to 15-day-old male and female boll weevils of the ebony strain that were fed cotton squares (buds). 2. 2. O2 uptake was found to range between 19.51 and 10.64 μl O2/mg wet wt/hr for males and between 17.6 and 11.1 μl O2/mg wet wt/hr for females. 3. 3. Peak O2 uptake for males was recorded when they were 5 and 11–12 days old. 4. 4. Peak O2 uptake for females was recorded when they were 6 and 12 days old.

Uric acid in nucleic and amino acid synthesis in the boll weevil, Anthonomus grandis

Abstract When uric acid-2-14C was injected into the boll weevil, Anthonomus grandis, it was metabolized to RNA, DNA, amino acid, and 14CO2 at the end of 2 hr. The free amino acids, lipoamino acids, and protein amino acids were all labelled with the free amino acids showing the highest specific activity. Incorporation in DNA was slight, but it was extensive in RNA; cytidylic acid showed the greatest amount of incorporation.

Free amino acids in the plasma and red cells of the ox, Bos taurus

1. 1. Twenty-one free amino acids were found in erythrocytes and plasma of the ox, Bos taurus. 2. 2. A physiological meaning for high aspartic acid and proline concentrations in erythrocytes is suggested.

Oxygen uptake in larval bollworms (Heliothis zea) infected with the fungus Nomuraea rileyi

Abstract 1. 1. Healthy 6- to 12-day-old Heliothis zea (bollworm) larvae showed a mean oxygen uptake of 3.1 μl O2/mg body wt per hr. 2. 2. Similar larvae infected with the fungus Nomuraea rileyi had a mean uptake of 4.01 μl O2/mg per hr. 3. 3. The weights of the two groups of insects did not differ. 4. 4. T-test showed a significant (P

The effect of various levels of contamination by two species of bacteria (staphylococcus aureus and streptococcus sp.) on oxygen uptake of the boll weevil

1. 1. When oxygen uptake of 1, 5, or 10 day old boll weevils contaminated with Streptococcus or Straphylococcus aureus was measured, it tended to increase in staph-infected weevils as the degree of infection increased, and tended to decrease in strep-infected weevils. 2. 2. There was a significant (P < 0.05) increase in weight in the 5 day old staph-fected weevils as bacterial load increased. There was a trend to weight gain in the 1 day old group. 3. 3. There was no significant (P > 0.5) relationship between weight of the insects and bacterial load of the strep-infected weevils.