Evidence for large superhumps in TX Col and V4742 Sgr

Since the discovery of the largest positive superhump period in TV Col, we have started a program to search for superhumps in CVs with large orbital periods. Here, we summarize preliminary results of TX Col and V4742 Sgr. TX Col is an intermediate polar with a 5.7-h orbital period. V4742 Sgr is a recent nova with no known periods. CCD unfiltered continuous photometry of these 2 objects was carried out during 56 nights in 2002-3. In TX Col, in addition to the orbital period of 5.7 h, we found peaks at 7.1 h and 5.0 h. These are interpreted as positive and negative superhumps correspondingly, although the effects of the quasi-periodic oscillations at about 2 h were not taken into consideration. In the light curve of V4742 Sgr 2 long periods are detected -- 6.1 and 5.4 h as well as a short-term period at 1.6 h. This result suggests that V4742 Sgr is an intermediate polar candidate and a permanent superhump system with a large orbital period (5.4 h) and a superhump period excess of 13 percent. If these results are confirmed, TX Col, V4742 Sgr and TV Col form a group of intermediate polars with extremely large superhump periods. There seems to be now growing evidence that superhumps can occur in intermediate polars with long orbital periods, which is very likely inconsistent with the theoretical prediction that superhumps can only occur in systems with mass ratios below 0.33. Alternatively, if the mass ratio in these systems is nevertheless below the theoretical limit, they should harbour undermassive secondaries and massive white dwarfs, near the Chandrasekhar limit, which would make them excellent candidates for progenitors of supernovae type Ia.Comment: 9 pages, 8 figures, 3 sty files, To appear in the proceedings of IAU JD5, `White Dwarfs: Galactic and Cosmological Probes', eds. Ed Sion, Stephane Vennes and Harry Shipman, Full abstract in pape

Insecticidal control of funnel ants in turf

In 2 trials of 3 insecticides against Aphaenogaster spp. in lawns in south-eastern Queensland in 1977 and 1980, chlorpyrifos, diazinon and isazofos at 1000 g/ha gave good control when used as a mound drench

Effect of fruit fly sprays on the abundance of the citrus mealybug, Planococcus citri (Risso), and its predator, Cryptolaemus montrouzieri Mulsant, on passion-fruit in south-eastern Queensland

The effects are reported of 3 insecticidal treatments used against Dacus tryoni (Frogg.) on populations of Planococcus citri (Risso) and its main predator Cryptolaemus montrouzieri Muls. on passion fruit in south-eastern Queensland in 1975-76

Population studies of the citrus mealybug, Planococcus citri (Risso), and its natural enemies on passion-fruit in south-eastern Queensland

Field populations of Planococcus citri (Risso) and its natural enemies on passion fruit were sampled fortnightly in south-eastern Queensland from March 1974 to March 1976

Pineapple scale (Diaspis bromeliae (Kerner)) distribution and seasonal history

A survey conducted to ascertain the distribution of Diaspis bromeliae (Kerner) found that it was widely distributed in south-eastern Queensland. Studies on its seasonal history at two sites near Nambour between June 1977 and October 1978 showed that the percentage of living adult female scales was highest during June, September and December 1977 and August 1978. Combined mortality from parasitism and predation averaged 40.7% and 37.8% respectively, at the two sites studied

Effects of sticky banding of custard apple tree trunks on ants and citrus mealybug, Planococcus citri (Risso) (Pseudococcidae (Hem)) in south-east Queensland

The application of sticky bands to the trunks of custard apple trees in south-eastern Queensland in 1979-80 reduced the numbers of ants (Pheidole megacephala (F.)) in the trees and resulted in lower, though still unacceptably high, levels of P. citri infestation

Abundance and mortality of overwintering pupae of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) on the Darling Downs, Queensland, Australia

Surveys were conducted between 1997 and 2001 to investigate the incidence of overwintering Helicoverpa spp. pupae under summer crop residues on the Darling Downs, Queensland. Only Helicoverpa armigera was represented in collections of overwintering pupae. The results indicated that late-season crops of cotton, sorghum, maize, soybean, mungbean and sunflower were equally likely to have overwintering pupae under them. In the absence of tillage practices, these crops had the potential to produce similar numbers of moths/ha in the spring. There were expected differences between years in the densities of overwintering pupae and the number of emerged moths/ha. Irrigated crops produced 2.5 times more moths/ha than dryland crops. Overall survival from autumn-formed pupae to emerged moths averaged 44%, with a higher proportion of pupae under maize surviving to produce moths than each of the other crops. Parasitoids killed 44.1% of pupae, with Heteropelma scaposum representing 83.3% of all parasitoids reared from pupae. Percentage parasitism levels were lower in irrigated crops (27.6%) compared with dryland crops (40.5%). Recent changes to Helicoverpa spp. management in cotton/grain-farming systems in south-eastern Queensland, including widespread adoption of Bt cotton, and use of more effective and more selective insecticides, could lead to lower densities of overwintering pupae under late summer crops

Methyl bromide fumigation of pineapple scale, Diaspis bromeliae (Kerner)

Crowns, suckers and slips of Smooth Cayenne pineapples infested with D. bromeliae were fumigated in a fumigation chamber with methyl bromide at 27-55 g/m3 for 2 h at 20 deg C. Fumigation at 46 or 55 g/m3 eliminated D. bromeliae, assessed 14 days later. No phytotoxicity was caused on disease-free material, but suckers severely infected with Phytophthora cinnamomi suffered severe leaf burn at all dosage rates. ADDITIONAL ABSTRACT: Diaspis bromeliae (Kerner), an occasional pest of pineapple in south-eastern Queensland, was eliminated from pineapple planting material by fumigating with methyl bromide at a dosage of 46 g/m3 for 2 h at 20 deg C. This could be used to prevent the spread of the scale to uninfested districts

Studies on the stinging of passionfruit by Queensland fruit fly, Dacus tryoni and its control by bait and cover sprays

It was confirmed that the main economic loss in passion fruit in Queensland resulting from stinging of the fruit by the tephritid Dacus tryoni is the downgrading in quality of the mature fruit, which shows the effects of the stinging