1st Generations Research Articles

Apple, Evaluation of Insecticides on Indirect Pests, 1996

Abstract Experimental sprays were applied to single-tree plots in a randomized block design consisting of 4 replicates of ‘Yorking’. Treated single trees were separated by others not sprayed with insecticides. The trees were 8 years old and planted at a spacing of 20 x 30 ft. All treatments were applied with a Myers Mity Mist sprayer calibrated to deliver 100 gpa driven at 2.4 mph. All plots recieved a regular fungicide maintenance schedule of Benlate 50DF, Dithane 75DF, Nova 40WP and Ziram 76WP and the insecticide Imidan 70WP. All maintenance materials were applied using the alternate row middle method of application. The effect of the sprays on WALH was evaluated by counting the number of nymphs/25 injured leaves/tree. Effectiveness on the spirea aphid was evaluated by counting the number of aphid-infested leaves/10 top terminals, and by rating the density of aphids/most infested leaf on 0-4 scale as explained in the table footnotes. The number of natural enemies of aphids was determined by counting the number observed on 10 growing shoots per tree. Effectiveness of the test chemicals on ERM was evaluated by counting the mites several times during the season on samples of 25 random leaves/tree, 100 leaves/treatment. The predator, S. punctum, was observed by making 3-min counts of adults and larvae around the periphery of the trees. STLM was evaluated by a 5-min count of tissue-feeding mines around the periphery of the trees at the end of the 1st and 2nd generations. Also, STLM parasitism was evaluated at the end of the second generation by collecting 25 random leaves/tree and dissecting the mines found. Pest pressure was moderate throughout the season.

Inundative Release of Common Green Lacewings (Neuroptera: Chrysopidae) To Suppress Erythroneura variabilis and E. elegantula. (Homoptera: Cicadellidae) in Vineyards

The effectiveness of inundative release of common green lacewing, Chrysoperla carnea , (Stephens) to suppress 2 vineyard pests, Erythroneura variabilis Beamer and western grape leafhopper, E. elegantula Osborn, was examined in small-plot and on-farm trials. In 1900, C. carnea larvae were hand-released into quarter-vine cages. Leafhopper densities were significantly reduced by 23.5 and 30.3% in plots that received 29,652 and 88,956 C. carnea larvae per hectare, respectively, as compared with no-release plots. In 1991, C. carnea larvae were hand-released onto vines in uncaged, 3-vine plots; the 2 release rates used closely reflected commercial recommendations. At the lower rate (9,884 larvae per hectare), no significant differences were found between C. camea -release and no-release plots. At the higher rate (19,768 larvae per hectare), leafhopper densities were significantly reduced by 33.6 and 31.4% in 1st and 2nd leafhopper generations, respectively. In 1992, 3-vine plots were again used and the 3 commercially available lacewing species [ C. carnea , Chrysoperla c0manche Banks, and Chrysoperla rufilabris (Burmeister)] were tested at a release rate of 19,768 larvae per hectare. The only significant reduction in leafhopper density was in the C. rufilabris release treatment. From 1990 to 1993, the effectiveness of commercial release programs was tested in on-farm trials using large, replicated C. carnea -release and no-release plots. C. carnea was released at rates between 7,413 and 37,065 eggs per hectare per leafhopper generation. In 9 of 20 trials, leafhopper densities were significantly lower in C. carnea -release than norelease plots. Data from all trials were combined to determine possible explanations for the variation in the effectiveness of C. carnea releases. Possibilities include differences in release trials, rates, and methods, as well as prey density. The average reduction of leafhoppers in C. carnea -release plots, as compared with no-release plots, was 29.5% in cages, 15.5% in 3-vine plots, and 9.6% in commercial vineyards. A significant, although only weakly positive, correlation was found between release rate and effectiveness. There was also a greater reduction of leafhopper nymphs when lacewings were released as larvae, as compared with eggs. Combining data from all studies, the number and percentage of reduction of leafhopper nymphs was related to leafhopper density. Most importantly, when leafhopper densities were above the suggested economic injury level (15–20 nymphs per leaf), the reduction in leafhopper number was frequently not sufficient to lower the leafhopper density below the economic injury threshold.

Inf1uence of Citrus Leaf Nutrition on Survivorship, Sex Ratio, and Reproduction of Euseius tularensis (Acari: Phytoseiidae)

Citrus trees, Citrus sinensis (L.) Osbeck, grown in pots were fertilized weekly for 3 mo after grafting with 1, 1/10, 1/100, or 1/1,000× concentrations of a fertilizer solution. Eggs of the predaceous mite, Euseius tularensis (Congdon), were placed with ice plant, Malephora crocea (Jacquin) pollen on excised leaves, and no differences in survivorship or sex ratio were found during the 1st or 2nd generations of rearing. During the 2nd generation, however, egg production by E. tularensis reared on leaves from the 1× fertilized trees was higher both on the 1st d of oviposition and throughout most of the lifespan of the females compared with the other treatments. As fertilizer concentration decreased, fewer total eggs were deposited by E. tularensis females. Leaf analyses revealed significant, decreasing linear responses in concentrations of N, K, Mn, and Zn in the leaves as fertilizer concentration was decreased. Decreasing concentrations of N and Mn were significantly correlated with decreasing reproduction in the predaceous mite. These data suggest that E. tularensis feeds on leaf sap and its reproductive tential is influenced by the nutritional status of the citrus tree.

Field-Based, Degree-Day Model for Pink Bollworm (Lepidoptera: Gelechiidae) Development

Lower and upper developmental temperature thresholds of 13.9 and 32.8 degrees C were determined for the pink bollworm, Pectinophora gossypiella (Saunders), using 21 occurrences documenting overwintering larvae to adult moth development in the field. The events were induced by irrigation of pink bollworm infested cotton bolls held in emergence cages in experiments conducted from 1987 through 1991 in the Palo Verde Valley, CA. The whole day, sine wave method with a horizontal upper cutoff was found to be the best of several methods for calculating daily degree-days. Dates of beginning and peak spring moth emergence from overwintering diapaused larvae were determined from plots of male moth captures in 48 pheromone-baited survey traps situated along roadsides throughout the cotton producing area. Using the same method, degree-days from 1 February (determined to be the best starting date for heat accumulation) to the peak of spring moth emergence were calculated to be 510 DD (centigrade). Two weeks before peak infested cotton flowers was used as the date for initial in-field infestation. Numbers of male pink bollworm moths captured in field-situated pheromone traps were used to establish subsequent peak activity points for the 1st and 2nd generations. Using 12 of these generation events and the 13.9/32.8 degrees C thresholds, horizontal cutoff, and whole day sine wave method, the degree-days for 1 generation, adult to adult, were determined to be 492 DD. These field-derived thresholds corresponded well with thresholds obtained by some researchers using constant temperature laboratory trials

Dicymolomia julianalis (Lepidoptera: Pyralidae) on Selected Hosts in Eastern and Middle Tennessee

The pyralid Dicymolomia julianalis (Walker) has an unusually diverse range of hosts. In this study, the life cycle, feeding habits, and biological control potential of D. julianalis were evaluated on 3 hosts (musk thistle, Carduus nutans L. ssp. leiophyllus (Petrovic) Stojanov & Stefanoff; the common bagworm, Thyridopteryx ephemeraeformis (Haworth); and cattail, Typha spp.) at 3 sites in eastern and middle Tennessee. During this 2-yr study, 3 generations per year of D. julianalis were inferred. The 1st, 2nd, and 3rd (overwintering) generations occurred on cattail, dead or dying musk thistle, and within bagworm egg clusters, respectively. Second-generation individuals also were reared from cattail. Of these 3 hosts, cattail is believed to be the primary host of D. julianalis throughout the year in Tennessee. Infestation levels, averaged across all sites, were 11.6, 14.2, and 95.0% on musk thistle, bagworm, and cattail, respectively. Larvae of D.julianalis may simply feed as scavengers within seed heads of musk thistle and have limited effect on seed production and survival of musk thistle. However, D. julianalis may have potential as a biological control agent of bagworm.

A Simulation model for the arrowhead scale (Hemiptera: Diaspididae) population dynamics on citrus trees in relation to pest‐management programs

1. A mathematical model was constructed describing population dynamics of the arrowhead scale,Unaspis yanonensis Kuwana. The population occurrence patterns simulated by the model from 1971 to 1976 were relatively consistent with the actual findings in the field. 2. The effects of control tactics for this pest were examined on the basis of the model. 3. Effective timing of insecticide (petroleum oil and organophosphorous insecticide) application was indicated to be 40 days after the initial appearance of 1st-instar nymphs in both the 1st and 2nd generations of the host. 4. The number of overwintering adult females in May of the next year (i.e., the starting point of the next year’s population) decreased linearly with the increment in the degree of insecticide coverage. The pest populations were expected to be kept to low densities by petroleum oil sprays alone for the 1st generation when overall, complete coverage was accomplished. 5. Examination of the effects of two introduced parasitoids,Aphytis yanonensis andCoccobius fulvus, showed that they were able to control the scale population by themselves when more than 70% parasitism was achieved. When petroleum oil was applied to overwintering adults (termed winter petroleum oil) at the degree of coverage of 0.8, host populations were reduced by ca. 60% parasitism. When the winter petroleum oil was combined either with additional petroleum oil 40 days after the initial appearance of 1st-instar nymphs of the 1st generation or with an organophosphorous insecticide 40 days after the initial appearance of 1st-instar nymphs of the 2nd generation (degree of coverage=0.8 in each case), 40% parasitism led the reduction of the pest population. 6. The most desirable control program was considered to be one in which winter petroleum oil was used every year and additional petroleum oil or an organophosphorous insecticide was also used in those years when host density was high.

Control of Colorado Potato Beetle with Natural Product Insecticides, Rosemount, 1990

Abstract Natural product insecticides used in this experiment were Bacillus thuringiensis var. san diego (MYX 1806), and B. thuringiensis var. tenebrionis (Trident and BK-102) and azadirachtin (Margosan-O RH 0000 and RH 9999) from the neem tree, Azadirachta indica. Certified B-size seed potatoes were planted 23 May at the Plant Pathology Farm, Rosemount Agricultural Experiment Station, University of Minnesota. Plots were 6 rows wide, 19.8 m (65 ft) long, with 102 cm (40 in) spacing between rows and 30 cm (12 in) between plants. Plots were separated on all sides by 2 m (6.7 ft) of cultivated soil. A completely randomized plot design with 4 replications was used. Plots were scouted daily for CPB egg masses beginning 15 Jun. When egg masses were found these were flagged and checked daily for hatch. Timing of first spray application was based on egg hatch. Three basic spray schedules were used: first application on 30% hatch of flagged egg masses and subsequent applications on either a 7 d or 10 d schedule, or first application on 30% hatch of all eggs (unflagged) laid on or before that sampling date and subsequent applications on a 7 d schedule. Plots were sprayed 1-4 times for each generation of CPB larvae. Spray dates were: 21 Jun (30% hatch of flagged eggs—1st generation), 25 Jun (30% total hatch—1st generation), 29 Jun, 1, 2, 5, 9, 20 Jul (30% hatch of flagged eggs—2nd generation), 25 Jul (30% total hatch—2nd generation), 27 Jul, 30 Jul, 1,3, 8, 9, 10 and 15 Aug. Insecticidal sprays were applied using a tractor-drawn boom sprayer with drop nozzles, 3 hollow-cone drop nozzles to the row. Sprays were applied in 795 liters water/ha (85 gal/acre) at 620 kPa (90 psi). All data was collected from the center 4 rows of each plot. CPB larvae (small = 1st and 2nd instar, large = 3rd and 4th instar) were counted on 20 randomly selected whole plants/plot. On one sampling date, 6 Jul, CPB counts were based on only 10 plants/plot and not recorded by size-class. PLH nymphs and green peach aphid apterae were counted on 35 mid-plant leaves/plot. Leaf loss to defoliation (by CPB) was estimated visually (by 2-5 individuals per sampling date) as percent foliage lost. Hopperburn (the injury caused by PLH) was estimated visually (by 2-5 individuals/sampling date) on a 0-6 scale, 0 = no injury. CPB were counted on 26 Jun, 6, 31 Jul, 8, 15, 20 and 28 Aug. PLH were counted 3, 10, 16, 24 and 31 Jul, 6, 13, 21 and 29 Aug. GPA were counted 3 Jul, 6, 13, 21 and 29 Aug. Defoliation was estimated 29 Jun, 2, 5, 10 and 16 Jul, 2, 7, 10, 16, 23 and 30 Aug. Hopperburn was estimated on 10, 16, 23 and 30 Aug. Data was expressed as mean insect numbers or plant injury × number of days elapsed (= Area Under Curve). AUC for CPB was calculated separately for 1st and 2nd generations, and then combined. For calculation of AUC for 1st generation CPB the 6 Jul counts were multiplied × 2 and included in the column CPB large. Two way analysis of variance was used to test for treatment differences in pest densities, plant injury and yield. Yields were obtained 17 Sep by harvesting one center row from each plot.

Control of Colorado Potato Beetle with Natural Product Insecticides, Grand Forks, 1990

Abstract Natural product insecticides used in this experiment were Bacillus thuringiensis var. san diego (MYX 1806), B. thuringiensis var. tenebrionis (Trident and BK-102) and azadirachtin (Margosan-O) from the neem tree, Azadirachta indica. Plots were planted 15 May at the Research Farm, Red River Valley Potato Growers Association, Grand Forks, N.D. Plots were 6 rows wide, 16.8 (55 ft) long, with 91 cm (36 inches) spacing between rows and 30 cm (12 inches) between plants. The two center rows of each plot were planted with certified 'Red Pontiac' seed pieces, the remaining four rows were planted with certified, B-size, 'Russet Burbank.' Plots were separated on all sides by 1.8 m (6 ft) of cultivated soil. A completely randomized plot design with 4 replications was used. Plots were scouted daily from CPB egg masses beginning 21 Jun. When egg masses were found these were flagged and checked daily for hatch. Timing of first spray application was based on egg hatch. Three basic spray schedules were used: first application at 30% hatch of flagged egg masses and subsequent application on either a 7 d or 10 d schedule, or first application at 30% hatch of all eggs (unflagged) laid on or before that sampling date and subsequent applications on a 7 d schedule. Plots were sprayed 1-3 times for each generation of CPB larvae: 29 Jun (30% hatch of flagged eggs—1st generation) 2 Jul (30% total hatch—1st generation), 5,9, 12, 16, 19 and 31 Jul (30% hatch of flagged eggs—2nd generation), 6 Aug (30% total hatch—2nd generation), 10, 13 and 14 Aug. Insecticidal sprays were applied using a tractor-mounted boom sprayer, with a single Teejet nozzle over each row. Sprays were applied in 150 liters water/ha (40 gal/ acre) at 275 kPa (40 psi). All data were collected from the two center rows of each plot. CPB larvae (small = 1st and 2nd instar, large = 3rd and 4th instar) were counted on 20 randomly selected whole plants per plot, PLH nymphs were counted on 35 mid-plant leaves per plot. Leaf loss to defoliation (by CPB) and hopperbum (injury caused by PLH) were estimated visually (by 2 individuals per sampling date) as percent foliage lost. CPB were counted on 4, 10 and 17 Jul, and 1, 8 and 17 Aug; defoliation was estimated on 10, 17 and 24 Jul, 1, 8 and 15 Aug; PLH were counted on 4, 10, 17 and 24 Jul, 1, 8 and 17 Aug; hopperbum was estimated on 1, 8 and 15 Aug. Insect data and plant injury ratings were expressed as mean insect numbers or plant injury × number of days elapsed (= Area under Curve). AUC for CPB was calculated separately for 1st and 2nd generations, and then summed. Yields were obtained 2 Oct by harvesting one center row from each plot. Two way analysis of variance was used to test for treatment differences in pest densities, plant injury and yield. The 1990 growing season at Grand Forks was characterized by severe drought from late Jun through harvest.

The effect of Cydia molesta on the incidence of Monilinia spp. on quince fruits

A 2‐year study was performed on the effect of Cydia molesta on the incidence of Monilinia spp. on quince fuits. In Yugoslavia C. molesta regularly occurs in the Čačak area (western Serbia) and is a highly important pest of peach and quince. In Yugoslav conditions it develops four generations a year. The 1st and 2nd generations usually develop on peach and the 3rd and 4th on quince. The proportion of quince fruits injured by C. molesta can reach 78%, with up to 12 caterpillars per fruit. C. molesta had a great effect on the incidence of Monilinia spp. on quince fruits. Of the total number of fruits affected by fruit rot, 84 and 88% had been injured by C. molesta in 1987 and 1988, respectively. Timely control of C. molesta is the most effective measure against the incidence of Monilinia spp. on quince fruits.

Some observations onStrongwellsea castrans [Zygomycetes: Entomophthorales], a parasite of root flies [Delia spp.], in the south of Scotland

Root flies,Delia radicum (L.) andD. floralis (Fallen) (Diptera: Anthomyiidae), trapped in swede crops in the south of Scotland, were infected withStrongwellsea castrans Batko and Weiser (Zygomycetes: Entomophthorales). The pathogen was associated mainly with females of the 1st and 2nd generations ofD. radicum and of the single generation ofD. floralis. Disease incidence showed time-lagged density dependence. Greatest sustained infection levels were recorded in the coolest wettest season. Higher proportions ofD. radicum were infected in the headland than in the crop. Unbaited yellow water traps caught greater proportions of infected flies than traps baited with mustard oil (allyl isothiocyanate). The reasons for high levels of infection in Scotland are discussed.

Entomophthora muscae (Entomophthorales: Entomophthoracae) mycosis in the onion fly, Delia antiqua (Diptera: Anthomyiidae)

Entomophthora muscae was identified as a common fungal pathogen of the onion fly, Delia antiqua, and the adult seed corn maggot, D. platura. Low infection levels also were found in populations of the cluster fly, Pollenia rudis (Diptera: Muscidae), and the tiger fly, Coenosia tigrina (Diptera: Muscidae). The disease cycle, as it affects D. antiqua in the onion agroecosystem, is described, including the etiology, symptomatology, and phenology. Natural infection levels approaching 100% were noted early in the spring and in late fall, impacting the 1st and 3rd generations of the D. antiqua population significantly. A lagged density-dependent disease response was noted at the gross population level, although more specific biological interactions may be involved in regulating the disease intensity.

Problems and Possibilities in the Study of American Immigration and Ethnic History

In the study of the history of immigration and ethnicity scholars often write about their own ethnic groups. For several reasons that pattern has led to an over-emphasis on the new immigrants of the early 20th century, a limitation of focus to the experiences of the 1st and 2nd generations of individual immigrant groups, and a disinterest in immigration and ethnicity as processes. Efforts to produce comparative studies of various kinds and to use survey data as a source of primary information about later generations may help correct those shortcomings. Today, the study of immigrant and ethnic history is at an important moment in its evolution. The concentration of attention on individual nationalities, the focus on the immigrants and their children to the neglect of the experiences of later generations in America, and the imposition of interpretive schemas that tell more about the ideology of the host society than about the experiences of the newcomers have left disturbing gaps and imbalances in the investigation.

Inheritance of solar direction finding in sandhoppers

The capacity ofTalitrus saltator populations to adapt to variations in shoreline directions within a limited space was evaluated by testing both adults collected at different points along continuous sandy arcs, and the 1st and 2nd generations of their laboratory-born offspring (exposed to the sun for the first time during testing). Solar orientation of the adults was adapted to the direction of the shoreline at the capture point, and significant statistical differences appeared between lots from different points. The innate directional tendency of the laboratory-born populations differed between collecting points only a few km apart. Solar direction-finding is thus genetically determined, and these results presuppose a genetic heterogeneity within the natural populations. Individually acquired components could improve orientation in nature.

ナシチビガの千葉県における有効積算温量・臨界日長と発生経過

Linear relationship was found between the cumulative heat units above the lower threshold of development and the probit of cumulative percentage of adult catches. The cumulative heat units estimated by using the equations were 120 day-degrees for the development from pupa to adult in the overwintered generation and 430, 480, and 580 day-degrees for the completion of development (egg-adult) in the 1st, 2nd, and 3rd generations, respectively. Diapause was induced under the condition of short day-length, and the critical day-length was estimated to be about 13hr. 30min.

Methylmercury: Reproductive and Behavioral Effects on Three Generations of Mallard Ducks

Three generations of mallard ducks (Anas platyrhynchos) were fed either a control diet or a diet containing 0.5 ppm mercury in the form of methylmercury. The levels of mercury in adult tissues and eggs remained about the same over 3 generations. The methylmercury diet had no effect on adult weights or weight changes during the reproductive season. Females fed a diet containing 0.5 ppm mercury laid a greater percentage of their eggs outside their nestboxes than did controls, and also laid fewer eggs and produced fewer ducklings. Methylmercury in the diet appeared to result in a small amount of eggshell thinning. Ducklings from parents fed methylmercury were less responsive than controls to tape-recorded maternal calls, but were hyper-responsive to a frightening stimulus in avoidance tests; there were no significant differences in locomotor activity in an open-field test. J. WILDL. MANAGE. 43(2):394-401 The purpose of this paper is to describe reproductive and behavioral effects of methylmercury on 3 generations of mallard ducks. Findings for the 1st and 2nd generations were reported earlier (Heinz 1974, 1975, 1976b, 1976c, Heinz and Locke 1976). Here, I have combined the data for all 3 generations to determine changes from generation to generation and overall effects that might not have been statistically significant in the analysis of single generations. To my knowledge, there have been no reported multiple generation studies on the effects of mercury or any other environmental pollutant on waterfowl. Such studies have been reported for Japanese quail (Coturnix coturnix japonica) (Carnio and McQueen 1973), ring-necked pheasants (Phasianus colchicus) (Dahlgren and Linder 1974), and ring doves (Streptopelia risoria) (Peakall et al. 1972). I thank the following people for their help in the study: C. S. Cruger, R. B. Frederick, D. C. Gray, R. G. Heath, P. A. Heinz, G. Hensler, and N. C. Miller. J. B. Elder provided the Morsodren used in this study and others. METHODS An abbreviated description of the care of adults, care of eggs and young, and behavioral tests is given below. Additional details were reported previously (Heinz 1974, 1976b, 1976c). A 1-way analysis of variance was used to check for changes in mercury levels in tissues from generation to generation. Reproductive and behavioral comparisons involved 2 factors (treatment and generation); these comparisons were made with a 2-way analysis of variance. A significance level of 0.05 was used. Generation effects are not discussed because significant differences from 1 year to another, if any, would not be related to mercury treatment but to other factors such as weather.

Calosoma sayi: Seasonal History and Response to Insecticides in Soybeans 1

Pitfall traps were used to monitor Calosoma sayi DeJean (Coleoptera: Carabidae) populations in soybean fields to determine the species' seasonal history, patterns of colonization, and response to insecticides. C. sayi adults were detected from mid-July into mid-Oct. Adults of the 1st and 2nd generations were separated by ca. 4 wk. Usually only 1 generation developed annually, but a 2nd generation developed in some instances. C. sayi adults quickly established populations in most areas where noctuid larvae were plentiful. However, no C. sayi were detected, even though abundant prey were available, in 2 relatively isolated soybean fields which had not been previously planted to soybeans. Methyl-parathion and methomyl treatments reduced the numbers of C. sayi larvae when these insecticides were applied when these forms were active. However, applications made before C. sayi activity began often resulted in higher adult and larval numbers later. Insecticide induced reductions of the beetles' biotic control agents and, more likely, a resurgence of noctuid prey in treated areas may have led to the increase in numbers of C. sayi after insecticide treatment.

キクキンウワバの有効積算温度と発生消長

The adults of Thysanoplusia intermixta (WARREN), visiting the flowers of Abelia grandiflora REHD. were collected in Fukuoka, and from these adults the eggs were prepared. The eggs, larvae and pupae were reared in incubators at 18, 20, 25 and 30°C. From the relationships between temperature and developmental velocity, the threshold of the development and thermal constant for completion of immature stages were calculated as 7.0°C and 580-625 day-degrees, respectively. From the seasonal prevalence of the adult emergence and the egg densities, four generations were recognized from June to October. In addition to these generations, the adult emergence of the overwintering generation was estimated in the period from April to early May in Fukuoka. The adult population densities were highest in the 1st and 2nd generations, and lowest in the 3rd generation.

Contributions to the ecology of cotton‐pests in Egypt

AbstractA field experiment was conducted during a crucial period of the cotton growing season (from May to August 1973). The main purpose of the experiment was to determine the egg‐laying distributional preferences on cotton in terms of both plant ‐ levels and cardinal directions. The results obtained revealed that an average of 50 cm from the ground is most preferable for the egg‐laying female moths. The determination of the average directional preference for egg‐laying indicated that the insect has a tendency to deposit its egg‐masses at the southern side of the field with an apparent preference of a south‐south‐easterly direction.If this is typical of most cotton growing areas, the 50 cm plant level (ranging from 40–60 cm) for the 1st and 2nd generations should be carefully inspected for hand‐picking as well as for pesticidal treatment.ZusammenfassungBeiträge zur Ökologie von Baumwollschädlingen in Ägypten. I. Studien über die Verteilung der Eiablage der Baumwolleule Spodoptera littoralis (Boisd.)Von Mai bis August 1973 durchgeführte Freilanduntersuchungen zeigten, daß die weiblichen Falter von S. littoralis zur Eiablage eine mittlere Höhe von 50 cm über dem Erdboden bevorzugten. Die meisten Eier fanden sich dabei auf der Südseite des Feldes.

Suppression of Heliothis spp. with Cottons Containing Combinations of Resistant Characters123

The use of nectariless, glabrous, and high-gossypol cottons and cottons with combinations of the 3 characters were evaluated against Heliothis species in replicated large field cages and in field plots. In cage tests, insect populations increased only 1.1 times (a maintenance population) between the 1st and 2nd generations on a cotton combining all 3 characters. Populations on glabrous plus high-gossypol cottons or on glabrous plus nectariless cottons increased 2-fold between the 1st and generations. Normal commercial types of cotton with none of the 3 characters had a 10–12-fold increase between generations. In the 1974 field tests, the glabrous plus high gossypol line yielded 700 lb/acre more seed cotton than the commercial check; and a high gossypol cotton (not glabrous) yielded 950 lb/acre more seed cotton. In field tests, glabrous plus high-gossypol cottons reduced populations of the bollworm, Heliothis zea (Boddie), and tobacco budworm, H. virescens (F.). A glabrous line suppressed larval populations by 68%, and 4 lines with a combination of both characters suppressed populations 60–88%. The nectariless character did not reduce insect populations because of the small size of the plots.

Lipidemia—A Multigeneration Predictability Study†

This study involved a 1st generation of 194 aged residents at the Philadelphia Geriatric Center plus 2nd and 3rd generations of 357 and 306 offspring, respectively. Serum cholesterol levels (including type of abnormality) and triglyceride levels were determined. The results suggest that hyperlipidemia at all ages is related to a familial genetic problem. The data on each generation, starting even with the 80-year-old parents, could be used to predict lipid abnormalities in each succeeding generations. However, when comparing the 1st generation with the 3rd generation, predictability was lacking, probably because of the inclusion of two sets of spouses and many enviromental factors that altered the situation. In the 2nd generation, 40 per cent of the subjects had an elevated lipid level compared to 30 per cent in the 1st and 3rd generations. The higher concentrations in the 2nd generation probably reflected increased risk factors such as improper diets, smoking, hypertension, obesity and stress at that age level. Hyperlipidemia in the aged apparently is not just a metabolic degenerative abnormality. It should be treated, as in younger people. Data on risk factors such as a high blood lipid level may help not only the aged, but succeeding generations.