Number Of Leaf Mines Research Articles

Evaluation of sequential sampling plans for estimation of leafmines density of Liriomyza sativae Blanchard (Diptera: Agromyzidae) in cucumber greenhouses

This study was conducted to develop sequential sampling plans to estimate leafmine density by Liriomyza sativae (Blanchard) at two fixed-precision levels in a cucumber greenhouse. The within-greenhouse spatial patterns of leafmines were aggregated. The slopes and intercepts of Taylor’s power law did not differ between years. A fixed-precision level sampling plan was developed using the parameters of Taylor’s power law generated from total number of leafmines in a cucumber leaf at two precision levels (D) of 0.1 and 0.25. The resulting sampling plans were tested with sequential bootstrap simulations (n = 500) using 10 independent data sets for validation. Bootstrap simulation within a wide range of densities demonstrated that actual D′ values at desired D = 0.25 averaged less than or equal to 0.25 in all cases. Even at the lowest density of leafmine (0.27 mine per leaf), the actual mean D′ was 0.24 at D = 0.25. This result shows that the sampling plan developed in this study is effective and reliable for estimating the mine densities in cucumber greenhouses.

Population of herbivores insects on different sides of Caryocar brasiliense (Caryocaraceae) trees in the Brazilian Cerrado region

The goal of this work was to study the distribution of lepidopteran, coleopteran, and hymenopteran herbivores and their natural enemies within the canopy of Caryocar brasiliense (Caryocaraceae) trees in the Brazilian cerrado. We observed thirteen rare, two common, and one constant species of herbivores insects; and three rare, eight common, and one constant species of natural enemies on C. brasiliense. The diversity, number of individuals and species of herbivores, and their natural enemies were similar among the cardinal orientation of the branches of the host tree. However, the number of fruits bored by herbivores was smaller on the south side of the trees. Scraped fruits and Lepidoptera leaf mines were more numerous on the west side of the trees. In the case of natural enemies, ants and predator bugs presented highest abundance on the leaves in the eastern and northern sides of the trees, respectively. We argue that this differential distribution of natural enemies negatively influenced the defoliation and number of leaf mines. We also suggest that the speed and direction of wind may affect the distribution of insect herbivores on the different sides of the trees, with higher populations prevailing on the wind safe sites of the trees. Key words: Beetles, canopy, caterpillars, insect distribution, natural enemies, pequi

Impact of nematode-induced galls on Miconia prasina (Sw.) DC (Melastomataceae) traits in the Atlantic forest of northeastern Brazil

We tested the hypothesis that parasitic Ditylenchus sp., leaf gall inductor, decrease plant performance by reducing the number of leaves, shoots, and plant height, increasing herbivory damage and nematode colonization in aggregate plants. We compared the effects on 30 paired healthy and attacked individuals of Miconia prasina. Nematode infection did not affect the number of leaves and shoots and plant height. The damage by free-feeding herbivores was greater in healthy plants, while the number of insect galls was higher in attacked plants. The number of leaf miners did not vary. Healthy plants were more grouped than the attacked plants, and the mean plant distance and the index of nematode attack were positively related.

Testing mating disruption of the horse chestnut leafminer Cameraria ohridella (Lepidoptera: Gracillariidae) in field tents

Since the beginning of the invasion of the horse chestnut leafminer, Cameraria ohridella Deschka and Dimic 1986 (Lepidoptera: Gracillariidae), into Europe over 20 years ago the damage to white flowering horse chestnut trees, Aesculus hippocastanum L (Sapindales: Hippocastanaceae) has remained extensive. This study evaluates the possible use of pheromone mating disruption as a control option against the horse chestnut leafminer. The heterogeneous distribution of ornamental trees in parks and gardens requires a different approach to evaluate pest control than in homogeneous crop fields, orchards or plantations where mating disruption is usually applied. For this reason we set up field experiments with host trees of the same age and size in field tents with a defined number of leafminers in two different densities. In the first experiment the effective quantity of newly developed C. ohridella pheromone dispensers was tested by recapturing males using traps baited with virgin females. Ninety-five percent less males were captured if three or more dispensers were positioned at a 4 m radius around the outside of an experimental tent. This set up was then used in the second experiment where male and female leafminers were released into field tents in order to assess the effect of pheromone on the reduction of leaf mining damage. Surprisingly, the pheromone dispensers were found to have no effect on the number of leaf mines at either low or high leafminer densities. Mating sites of the horse chestnut leafminer, multiple matings and distribution of pheromone dispenser are discussed as possible factors influencing the outcome in this study.

Causas químicas de resistência de Lycopersicon peruvianum (L.) a Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae)

Esta pesquisa foi conduzida em casa de vegetação na Universidade Federal de Viçosa e objetivou estudar a resistência dos acessos CNPH 101, 374 e 402 de Lycopersicon peruvianum a Tuta absoluta e as causas químicas dessa resistência. Os tratamentos foram as espécies de tomateiro Lycopersicon esculentum (cvs. Santa e IPA-5: padrões de suscetibilidade) e os acessos de L. peruvianum. Avaliaram-se o número de ovos / folha, de minas pequenas (comprimento < 0,5 cm) e grandes (comprimento > 0,5 cm) e a percentagem de folíolos minados por T. absoluta. Realizou-se extração hexânica nas folhas, e os extratos obtidos foram submetidos a cromatografia gasosa associada a espectrômetro de massa. Nos acessos de L. peruvianum contataram-se menores taxas de oviposição, percentagens de folíolos minados, números de minas pequenas e grandes de T. absoluta do que nas cultivares IPA-5 e Santa Clara. Foram detectados 69 picos nos cromatogramas do extrato hexânico das folhas com concentração relativa > a 10(6) íons x seg. Verificou-se efeito significativo (p < 0,05) da concentração relativa na intensidade de ataque de T. absoluta somente para os picos 28, 42, 46, 55 e 58. As principais substâncias relacionadas com L. peruvianum foram: ciclobutanol; ácido hexadecanóico; ácido 9-octadecenóico e hexadecano (picos 28, 42, 46 e 55, respectivamente). Já o tetracosano (pico 58) esteve associado com L. esculentum. Todas as substâncias presentes nos extratos hexânicos estiveram associadas com o aumento da suscetibilidade dos tomateiros a T. absoluta.

Apple, Insecticide Evaluations, 1993

Abstract Insecticides were applied to 10 year old ‘Ida Red’ apple trees on MM III rootstocks. Five three row plots were randomly selected and one was assigned to each treatment. The two outside rows served as guard rows. Data were collected from four or five replicate trees randomly selected from the middle rows in each plot. Treatments were applied with a power take off driven FMC (model 252S) sprayer calibrated to deliver 50 gpa (76.62 liters/ha.), a 6x concentration for this orchard. Treatments were applied on 27 Apr, 21 May and 6 Jul. Other insecticide sprays included a delayed dormant spray of superior oil (60 sec.) applied to the control and the Lannate + Guthion plots on 8 Apr. Guthion 35W (2 lb./A) was added to all sprays (including the 6 Jul treatment) on the NTN33893 plot on and after 18 Jun. Other materials used for orchard maintenance are given later in a table. Insect predators were sampled in a three minute visual count per tree. RAA & AA (complex of AA & SA) were counted as number of infested terminals in 10/replicate, or number of infested water sprouts in 10/replicate, or number in 10 terminals/replicate on which the terminal leaf was infested. Tentiform leafminer and WALH data indicate the number of leaf mines or leafhoppers/leaf present when ten leaves/replicate were examined. Mite data were generated using the Henderson McBurnie method of brushing 20-leaf samples from each replicate. Mites and eggs were counted with a binocular microscope. Data were transformed to either log 10x +1 or square root X + .5 for analysis.

Control of Leafminers and Armyworms on Fresh Market Tomatoes in West-Central Florida, Spring, 1991

Abstract Transplants were set 5 Mar, 15 inches apart on 8-inch-high beds of EauGallie fine sand covered with white polyethylene mulch. Each plot consisted of a single 15-ft row with rows on 5 ft centers. Treatments were replicated 4 times in a randomized complete block design and were applied with a 2.5 gal, handheld CO2-powered sprayer on 15, 24, 30 Apr, 6, 15, and 24 May. The sprayer was operated at 40 psi and 75 gal/acre using a single nozzle fitted with a D- 5 disk and #45 core. On 6 (after spraying), 7 and 8 May, the number of sweetpotato whitefly adults was estimated by counting the number dislodged from the upper foliage of five plants per plot. The foliage was shaken over a black aluminum pan with the bottom coated with a thin layer of vegetable oil. On 31 May, the number of leafmines was counted in a 1 minute search of selected treatments. Fruit were harvested on 20, 30 May, and 6 Jun and the number and weight of undamaged fruit and the number and weight of fruit damaged by noctuid larvae (primarily the southern armyworm), and stink bugs (primarily the southern green stink bug) were determined.

Insect Control on Fresh Market Tomatoes in West-Central Florida, Fall 1988

Abstract Transplants were set 16 Sep, 15 inches apart on Srinch-high beds of Eau Gallie fine sand covered with white polyethylene mulch. Each plot consisted of a single 15 ft row with rows on 5 ft centers. Treatments were replicated 4 times in a randomized complete blocks design and were applied with a 2.5 gal, hand held CO2-powered sprayer on 30 Sep, 7, 13, 20, 27 Oct, 3, 9, 16, 20 Nov, 8, and 14 Dec. The sprayer was operated at 40 psi and the volume was increased as the plants grew. Thus, the sprayer delivered 45 gal/acre the first application, 55 gal/acre the second application, 70 gal/acre the third and fourth applications, 85 gal/acre the fifth and sixth applications, 100 gal/acre the seventh application and 125 gal/acre for the remaining applications. The sprayer had a single nozzle fitted with a D-3 disk and #25 core. On 2 Dec, the number of leafmines was counted in a 1-minute visual search of each plot. Fruit were harvested on 5 and 20 Dec, and the number and weight of undamaged fruit and the numbers of fruit damaged by noctuid larvae (principally the southern armyworm, S. eridania (Cramer)) and the southern green stink bug were determined.

Evaluation of Vendex Plus Pydrin for Mite Suppression in Orchards, 1984

Abstract Treatments were applied in a comparative test to mature semi-dwarf Golden Delicious trees on 28 Jun with a Bean 35 gal/min hydraulic sprayer operating at 400 psi. Single tree treatments were used and replicated 4 times in a randomized block design. Trees were sprayed to runoff. Mite and egg populations were evaluated by randomly selecting 25 leaves per replicate in each treatment, brushing mites and eggs onto glass plates with a modified Henderson-McBurnie mite brushing machine and counting with a binocular microscope. A pre-treatment evaluation on 26 Jun showed an average of 1.54 mites and 4.55 eggs/leaf. Posttreatment evaluations were done on 3 Jul and at weekly intervals throughout Jul. SP populations began to increase during mid Jul on some treatments and were evaluated on 25 Jul by counting all adults and larva in a timed count of 3 min/replicate. Effects of the treatments on SPLM were evaluated by recording the number of leafmines observed in a timed count (3 min/replicate) on 25 Jul.

Control of Insects on Fresh Market Tomato in West-Central Florida, Fall 1982

Abstract Transplants were set 8 Sept., 18 inches apart on 2.5-ft-wide by 8-inch-high beds of Myakka fine sand covered with black polyethylene mulch. Plots consisted of 10 staked plants and were replicated four times in a randomized complete blocks design. Treatments were applied 7, 14, 21, 28 Oct., 9, 18, 23 Nov. , 3, 9, 17, and 22 Dec. with a 2.5 gal, handheld CO2 powered sprayer which was operated at 40 lb/in2 and delivered 50 to 140 gal/acre (averaged 110 gal/acre; gallonage increased as the plants grew). On 8 Dec, the number of large leafmines (ca. 0.5 inches or longer) were counted on the terminal three leaflets of the fourth fully expanded leaf from the tops of 10 branches per plot and the foliage excised and placed in 1 qt Fonda ice cream cartons. The cartons were incubated at ca. 80°F for 1 week and the numbers of leafminers puparia were counted. The number of undamaged fruit and the numbers of fruit damaged by armyworm larvae (principally the southern armyworm and a climbing armyworm), southern green stink bugs or both armyworm larvae and stink bugs were totaled over harvests taken on 15 and 29 Dec. Percentage data were transformed arcsine %/100 before analysis but data are presented in the original scale.

Visual Rating System for Assessing Liriomyza spp. (Diptera: Agromyzidae) Leafmining on Tomato1

A visual rating system was developed to assess the total number of leaf mines produced by Liriomyza spp. on tomato foliage samples. The system consisted of a scale from I to 8 which corresponded to increases in the estimated numbers of leaf mines from 0 to 24 per foliar sample. Under field conditions, the number of leaf mines estimated by the rating system was significantly correlated (r = 0.95, P < 0.05) with the actual number of leaf mines counted. The amount of time required to assess the number of leaf mines by the rating system was 80% less than that required by the counting method.

Insect Control on Tomatoes in Florida, 1981

Abstract Transplants were set Mar 4, 18 inches apart on 3 ft wide by 6 inch high beds of Immokalee fine sand covered with black polyethylene mulch. Plots consisted of 10 plants and were replicated 4 times in a randomized complete block design. Treatments were applied Mar 25, Apr 1, 9, 15, 22, 29, May 6 and 13 with a Solo motorized mist blower which was operated at 1300-1400 rpm (20-25 mph air velocity) and delivered 120 gpa. On May 14, the number of leafmines of the vegetable leafminer were counted on the terminal 3 leaflets of the fourth fully expanded leaf from the top of each plant/plot. The number of undamaged fruit and those damaged by the southern armyworm, tomato pinworm, and southern green stink bug were counted in a single harvest on May 20. After harvest, 5 plants/plot were cut and shaken and the numbers of stink bugs and larvae of southern armyworm, tomato pinworm and cabbage looper were counted.

Insect Control on Tomato, 1980

Abstract ‘Flora-Dade’ transplants were set Mar 6, 18 in apart on 3 ft wide by 6 in high beds of Immokalee fine sand covered with black polyethylene mulch. Plots consisted of 10 plants and were replicated 4 times in a randomized complete block design. Treatments were applied Mar 25, Apr 1, 9, 17, 24, 30, May 7 and 13 with a Solo motorized mist blower which was operated at 1300-1400 RPM (20-25 mph wind) and delivered 120 GPA. On Apr 29 and May 21, the number of leafmines of the vegetable leafminer (VLM) were counted on the terminal 3 leaflets (trifoliate) of the third fully expanded leaf from the tip of each plant/plot. The number of undamaged fruit and those damaged by larvae of the cabbage looper (CL), granulate cutworm (GCW) and tomato fruitworm (TFW) were counted in a single harvest on May 20. The following day, 5 plants/plot were cut and shaken and the number of dislodged larvae of the CL, GCW, and TFW counted.

Arthropod Control on Eggplant, 1980

Abstract Transplants were set Mar 21, 1980, 18 in apart on 2.5 ft wide by 8 in high beds of Myakka fine sand covered with black polyethylene mulch. Plots consisted of 10 plants and were replicated 4 times in a randomized blocks design. Treatments were applied to runoff using a 2.5 gal hand held stainless steel sprayer with a single adjustable cone nozzle. On May 8 the number of Glover’s mites and green peach aphids on the undersides of the third leaf from the top of the largest lateral of 5 plants per plot were counted. On Jun 12, the number of twospotted spider mites and green peach aphids were counted on the undersides of the third leaf from the top of the youngest lateral of 5 plants/plot. Counts were completed by brushing the leaves in a leaf brushing machine and counting the number of individuals trapped on 1/10 of the detergent-coated glass plate. Counts were adjusted to a per leaf basis. The number of holes and windows in these same leaves produced by cabbage looper larvae were also counted. On the same date, the total number of leafmines of the vegetable leafminer were counted on the second leaf from the bottom of 5 plants. Plots were harvested Jun 6, 13, 20, 22, 24 and 26 and the number and weight of undamaged fruit and fruit damaged by cabbage looper larvae determined.

Leafminer Control, 1977

Abstract ‘U&amp;I Hybrid 8’ sugarbeets were planted May 6, 1977, in Ritzville silt loam at Yakima, Washington, in plots 6 rows wide and 50 ft long. Each treatment was applied to 4 plots. The plants were irrigated with line sprinklers that provided 1/2 inch of water/h. Granules of the test materials were applied at planting time 4-6 inches deep and 2 inches to one side of the seeds. On June 13 the number of sugarbeet plants in 10 ft and the number of leafminers in 20 plants were determined in each of the 4 replicates of each treatment.

Tomato Insect Control 1976

Abstract ‘Marion’ tomatoes were transplanted July 26, 1976, in 6-ft rows with 20-inch spacing between plants. Treatment plots were replicated 4 times in a randomized block design. Each treatment plot consisted of a single, 25-ff row bordered on each side by an untreated row. The sprays were applied with a D. B. Smith 5-gallon, knapsack, hand-operated, compressed-air sprayer at the rate of 100 gal/A (40 psi) using a D. B. Smith #147 adjustable-cone nozzle. Applications were made on August 30, September 7, 13, 20, 27, October 5, and 13, 1976. In evaluating the various insecticidal treatments, the number of leafminers and number of pinworm mines/10 plants were counted along with the number of potato aphids/10 leaves selected at random and fruitworm-infested tomatoes/100 fruit. All counts were made on October 8. Unfortunately an unseasonably early frost on October 18 (28°F) destroyed so much foliage and fruit that it was impossible to take records thereafter, and the experiment was terminated.

Response of Liriomyza (Diptera: Agromyzidae) and Its Parasites to Stake and Mulch Culture of Tomatoes

The influence of tomato cultural systems, mulching and staking, on the leafminer, Liriomyza sativae Blanchard (= L. munda Frick) and its parasites was evaluated in 1973 in 1 spring and 2 fall field experiments at Bradenton, Florida. Leaf samples were examined for leafmines, and field collected pupae were held for parasite emergence. Both cultural techniques had a positive influence on Liriomyza and parasites. The number of leaf mines in tomato foliage from mulch culture and from stake culture was increased in the spring experiment but the same was true for only stake culture in the fall. Parasitism of leafminers by Opius spp. (Braconidae) was reduced by stake culture.

Comparison of Banded and Broadcast Application of Furadan for Control of Leafminers and Pickleworms, 1975

Abstract ‘Zapallo Courge Dixie’ squash was planted March 21, 1975 on seep-irrigated 0.8 m wide beds of Leon fine sand at 16% moisture and pH ranging from 7.3 to 8.6. Plots were 6.1 m long with two plants every 61.0 cm and 3.0 m alleys between four replications in a randomized complete block design. Due to damping off, some plants were removed and reseeded April 22 following application of Terraclor 15 (151 g/7.6 1/24.4 m of row) in a 20.3 cm band. Furadan was applied just prior to planting either in a 30.5 cm band (mixed to 5.1 cm depth) or by broadcasting over the entire planting bed and mixing to a 20.3 cm depth). The number of leaf mines on the third leaf from the crown was determined for ten giants on June 10 and 24. Harvest was completed on June 24 and the total number of fruit and the number damaged by pickleworm determined.

Variations in Leaf Miner and Flea Beetle Injury in Tomato Varieties1

As a result of a 3-fold experiment to evaluate damage by leaf miners and adult flea beetles, it was determined that the tomato ( Lycopersicon esculentum ) varieties Oxheart and Pearson A had the least tobacco flea beetle, Epitrix hirtipennis (Melsheimer), feeding scars and Purdue 1361 and Red Top V9 had the most. Clark’s Early Special, Rio Grande, and Pearson VF6 had the least larval mines of the leaf miner Liriomyza munda Frick, and Garden State Improved and Oxheart had the most. Varieties with genetic marker genes for jointless pedicels had the least flea beetle feeding scars and those with xanthophyllic foliage and bushy stem had the most. Plants with the genetic marker genes for tangerine-orange flesh-colored fruit had the least leaf miner counts and narrow cotyledon and trifoliate leaved plants had the most leaf miner mine infestations. Plants in genetic markers of linkage group III had the fewest flea beetle feeding scar counts and plants in genetic markers of VIII, I, and II had the most. Linkage groups I, II, III, and VII had the fewest leaf miner infestations while X, VIII, and VI had the most. Leaf miner mine and flea beetle feeding scar damage per plant is proposed for tomato varieties. The data were based on an average of 1.1 cm2 and 0.8 mm2 damage to each leaf by a leaf miner larval mine and an adult flea beetle feeding scar. Proposed number of leaf mines and flea beetle feeding scars to destroy 50% of the plant was 640 leaf mines and 8000 flea beetle feeding scars for plants averaging 40 leaves per plant.