Article is abstract only / Five transgenic lines of cotton, Gossypium hirsutum L., carrying the delta-endotoxin gene from Bacillus thuringiensis Berl., and two control cultivars, Coker 312 (the parent stock) and MDS1N (an adapted nectoriless line) were evaluated at the Maricopa Agricultural Centerfor resistance to attack by several insect pests and for agronomic properties. The transgenic lines were highly resistant to pink bollworm (PBW), Pectinophora gossypiella (Saunders), as shown by 90% fewer rosetted blooms, 96% fewer PBW recovered from incubated bolls, and 92% less seed damage than in the control cultivars. The transgenic lines were highly resistant to saltmarsh caterpillar, Estigmene acres (Drury), and beet annyworm, Spodoptera exigua (Hbn.), as shown by minimal damage to transgenic leaves and almost complete defoliation of control leaves. The transgenic lines were virtually immune to cotton leafperforator, Bucculatrix thurberiella Busch as shown by no apparent damage to transgenic leaves, and many mines, "horseshoes", and feeding areas on the control leaves. Compared to Coker 312, one transgenic line yielded more lint, and one yielded less. Four transgenic lines had higher lint percentages and all five had smaller bolls and were later maturing than Coker 312. Compared to MD51N, no transgenic line yielded more lint and one yielded less. All five transgenic lines had lower lint percentages, three had smaller bolls, and three were earlier maturing than MDS1N (USDA, ARS, Western Cotton Research Laboratory in cooperation with Monsanto Co. and Arizona Agricultural Experiment Station).

The effects of temperature on development and longevity of a Microplitis sp. from Australia on the beet armyworm, Spodoptera erigua (Hübner) was studied in the laboratory. Time of development ranged from 25 days at 15°C to 6.2 days at 27.5 °C. The parasite developed twice as fast as its beet armyworm host. Average longevities of male and female parasites were not significantly different.

Cottonseed oil applied to cotton repelled sweetpotato whitefly (SPW) adults up to 8 days in greenhouse tests. Soybean oil (5 %) resulted in reduced numbers of adults and numbers of eggs laid. SPW egg hatch was reduced 84% after treatment with 10% crude cottonseed oil solutions as measured by the number of first instar larval emergence. Also, numbers of whitefly larvae were reduced 99, 91 and 83% on day 6 following treatment with 10% cottonseed oil, S and 1.5% soybean oil, respectively. Negligible plant leaf phytotoxicity occurred from the plant-derived oil treatments.

Overwintered female boll weevils, Anthonomus grandis Boheman, collected in grandlure- baited traps were significantly leaner than weevils taken from winter habitat. Weevils that emerged from naturally infested cotton bolls tended to be fat as adults regardless of subsequent adult diet, but adult diet can affect gonadal development. Weevils that emerged from bolls in 1975 in South Carolina had a higher winter survival rate and emerged from winter habitat earlier than the total population. Migrant weevils appear to be mainly colonizers that have some body fat and medium size gonads. The physiological condition of migrants was fairly consistent over time and location in South Carolina but not in Arizona. The time of migratory flight was related mainly to plant maturity and population levels in South Carolina. Weevils collected from cotton plants in South Carolina and Arizona had significantly more body fat than weevils trapped at the cotton field but oogenesis was variable between the two locations.

The Marana-Avra Growers' Task Force and Arizona Cooperative Extension worked together to implement a comprehensive, community-wide insect management program. Growers worked in unison to implement a number of Integrated Pest Management techniques; including uniform optimal planting dates, trap cropping, pinhead square spray applications, in-season insect management, and late season management. This strategy focused on the area's primary pest, the pink bollworm (PBW). This program delayed the need to treat for PBW until late August and minimized secondary pest problems. However, research results on the effectiveness of trap crops were inconclusive.

Article is abstract only / In 1991 four Insect Pest Management studies were conducted to help understand the pink bollworm and aid in its control. The first two were replicated cage studies where cages were placed over the soil and insect emergence from the soil was monitored several times a week from January to mid-summer. The first had pink bollworm (pbw) infested bolls buried at 0, 2, 4 and 8 inches under the soil. The second had four plow down dates and sub -treatments of one or no irrigations. Perhaps due to the cold winter, few pink bollworm moths emerged in either study. In the buried infested boll study, no bolls buried at 8 inches produced pink bollworm moths in the spring and few emerged from either 4 or 2 inches. Of the bolls left on the surface, there was emergence from only some of the replications. Less than 1% of all of the potential moths emerged. In the plowing test, only 6 pink bollworms emerged in any of the 32 cages placed in the plots over the 18 weeks of the study. It appears to be a numbers game and the chance of having a pink bollworm emerge under a randomly placed cage in a field is very small. The second two tests involved Trichogramma bactrae, a trichogrammatid species imported from Australia. The first of these two studies involved placing laboratory produced pink bollworm eggs in a pattern around a release site for the parasitic wasps to determine their area of influence. This was done on three different occasions with varying success. The study was complicated by the fact that the wasp hatch must be coordinated with the pink bollworm egg deposition. Never-the-less, some pink bollworm egg parasitization took place. This study needs to be repeated. The second of these studies was two plots side-by-side, one treated with chemicals to control pink bollworm (and other insects), the other with weekly trichogramma releases during August and September. At the end of the season, 20 plants were removed from each plot and boll infestation and boll load were determined. The parasite controlled plots had a higher infestation level (35% to 23% with an LSD(05) of 9.9) than the chemically treated plots. There was no difference in the boll load between the two treatments. This study should be continued, preferably with a check plot so the value of the trichogramma can be evaluated more accurately.

Four Monsanto transgenic lines of Coker -312 containing the gene for endotoxin from Bacillus thuringiensis were compared to Coker-312 and MD51ne for resistance to the pink bollworm (PBW) and leaf-feeding lepidopterans. In 11 samples of 50 bolls per plot, 12 plots per line, collected 7/16 to 8/24, the transgenic lines averaged 0.13 PBW /100 bolls while the controls averaged 5.92 PBW /100 bolls. None of the bolls collected from the transgenic lines on 11/18 contained diapausing PBW larvae, while the control lines averaged 57 diapausing larvae /100 bolls. The transgenic lines generally had less leaf damage caused by beet armyworm, cabbage looper and saltmarsh caterpillar.

Four Pima cotton entries were grown in large plots at MAC, not treated with insecticide, to determine their response to attack of pink bollworm. P62, an early -maturing germplasm line, sustained significantly less seed damage caused by pink bollworm than did 'Pima S-6', Pima S-6 nectariless, and P62 nectariless. The nectariless trait did not reduce seed damage significantly.

Replicated, small-plot studies were conducted in 1991 to evaluate control of pink bollworm (PBW), Pectinophora gossypiella, by inundative releases of a newly imported Australian egg parasitoid, Trichogrammatoidea bactrae. Weekly release of parasitoids at equivalent rates of 165,000/HA beginning in mid-June significantly reduced egg and larval populations of PBW in comparison with control plots until mid-August, but provided no control thereafter. Rates of parasitism on artificially-placed PBW egg cards exceeded 90% until mid-July and then declined, becoming somewhat variable over the latter half of the season. Parasitism rates dropped near zero on three dates coinciding with drift from aerial pesticide application at a neighboring cotton field. The seasonal decline in rates of parasitism was not significantly related to increasing plant leaf area, vigor of released parasitoids, or ambient temperature. Parasitism of indigenous PBW eggs on cotton bolls was extremely low and this, along with moth migration from surrounding cotton, may have contributed to the lack of mid- to late-season control in our small plots. Results are encouraging and suggest that larger-scale release studies are warranted.

Reduction of populations of the B strain (poinsettia) of sweetpotato whitefly (SPWF), Bemisia tabaci Gennadius, resulted from applications of buprofezin or amitraz to cotton in central Arizona (Maricopa, AZ). Control was fair to good control for this insect. However, yields of seed cotton in treated plots were not increased significantly compared to untreated plots, following three applications of these insecticides during the season. Similar results on percentage sugar on lint and lint stickiness from honeydew of SPWF in both treated and untreated plots were obtained.