scholarly journals Control of Western Corn Rootworm Beetles and Effect on Spider Mites in West Central Nebraska, 1992

1994 ◽  
Vol 19 (1) ◽  
pp. 209-210
Author(s):  
R. C. Seymour ◽  
J. B. Campbell ◽  
R. J. Wright

Abstract Various pesticides were applied to blister stage (R6 stage) hybrid field corn on 10 Aug, near North Platte, in west central NE. The treatments were applied with a CO2 charged backpack sprayer through 8001 flat fan nozzles at 206,786 Pa (30 psi), in a total volume of 196.4 liter/ha (21 gal/ acre). Each treatment was applied to 3 × 10 m plots, replicated 4 times in a RCBD. Five days before the pesticide application Banks grass mites were applied to 2 plants in the center of each plot by attaching 2 well-infested leaves with strapping tape. Four days following application the number of rootworm beetles and predatory insects were evaluated by counting all beetles on four randomly selected plants in the middle of each plot. For each artificially infested plant size of mite colonies was rated on the underside of 3 leaves below the ear, the ear leaf and 2 leaves above the ear at 9, 17, 27 and 46 DAT. Ratings were made on a 0-6 scale where 0 = no mites, 1 = individual mites, 2 = small colonies, 3 = large, individual colonies, 4 = large connected colonies but not completely covering the underside of the leaf, 6 = leaf dead due to spider mite damage. In addition to evaluation of spider mite colonies, arthropod predators were also counted.

1994 ◽  
Vol 19 (1) ◽  
pp. 210-210
Author(s):  
R. C. Seymour ◽  
J. B. Campbell ◽  
R. J. Wright

Abstract Various pesticides were applied to blister stage (R6 stage) hybrid field corn on 9 Aug, near North Platte, in westcentral NE. The treatments were applied with a CO2-charged backpack sprayer through 8001 flat fan nozzles at 206,786 Pa (30 psi), in a total volume of 196.4 liter/ha (21 gal/acre). Each treatment was applied to 3 × 10 m plots, replicated 4 times in a RCBD. Three d before the pesticide application the number of WCR beetles was counted on 2 randomly-selected plants in the middle of each plot. Three d prior to application, 3 spider mite-infested plants in each plot were marked to follow population trends on the same plants. The size of twospotted spider mite colonies was rated on the underside of 3 leaves on each of these plants, one below the ear, the ear leaf and one leaf above the ear. Ratings were made on a 0-6 scale where 0 = no mites, 1 = individual mites, 2 = small colonies, 3 = large, individual colonies, 4 = large connected colonies but not completely covering the underside of the leaf, 5 = colonies completely covering the underside of the leaf, 6 = leaf dead due to spider mite damage. These plants were also evaluated for the presence of arthropod predators. Two d following application the number of rootworm beetles was evaluated by counting all beetles on two randomly selected plants in the middle of each plot. Previously marked plants were evaluated for the size of twospotted spider mite colonies and the presence of arthropod predators at 7, 14, 21 and 44 DAT. Data were statistically analyzed with analysis of variance and an LSD test was used for mean separation.


1996 ◽  
Vol 21 (1) ◽  
pp. 225-226
Author(s):  
R. C. Seymour ◽  
J. B. Campbell ◽  
R. J. Wright

Abstract Various pesticides were applied to milk stage (R7 stage) field corn on 14 Aug., near North Platte, NE. The treatments were applied with a CO2-charged backpack sprayer through 8001 flat fan nozzles at 30 psi (206, 786 Pa), in a total volume of 21 gal/acre (196.4 liter/ha). Each treatment was applied to 3 X 10 m plots, replicated 4 times, in a RCB design. Three days before the pesticide application the number of WCRW were counted on 4 randomly selected plants in the middle of each plot. In addition, the presence of spider mites was evaluated on the same plants by inspecting leaves below the ear leaf for colonies the size of a quarter or larger. The number of WCRW and the number of mite infested leaves were evaluated 3 and 14 DAT on 4 different randomly selected plants in the middle of each plot. In addition to counting the number of mite infested leaves, the size of the mite colonies was rated on a 0-6 scale, on the 3 lowest leaves of 4 different randomly selected plants 14 DAT.


1994 ◽  
Vol 19 (1) ◽  
pp. 209-209
Author(s):  
R. C. Seymour ◽  
J. B. Campbell ◽  
R. J. Wright

Abstract Granular insecticides were applied to suppress larval rootworm populations in 2 fields in west central NE. ‘Pioneer 3394’ hybrid field corn was ridge-planted in Field 1 with a John Deere Max-emerge planter, to a non-tilled seed bed on 11 May. Insecticides were applied at planting with insecticide boxes attached to the planter. Three replications of each treatment were arranged in a RCB design. T-band applications were made by applying a 7 inch band of insecticide in front of the press wheel. In-furrow applications were made by applying insecticide directly into the seed furrow. All insecticides were applied at a rate of 1114.5 g (AI)/ha. Field 2 was ridge-planted to ‘Fontanelle 4435’ and ‘Fontanelle 6240’ hybrid field corn with a John Deere Max-emerge planter, to a non-tilled seed bed on 6 May. With the exception of 4 strips, 12 rows in width, Counter 15G was applied at planting with insecticide boxes on the planter at a rate of 1114.5 g (AI)/ha. A granular and a liquid insecticide were applied to untreated strips in Field 2 immediately prior to cultivation on 15 Jun. The field corn plants were in the early whorl stage (growth stage 2) of development at the time of application. The granular application was applied over the whorl of the plants with insecticide boxes attached to a tool bar. The liquid insecticide was applied in a 7 inch band to the base of the plants in total volume of 120 liter/ha at 206,786 Pa (30 psi). Cultivation treatments were applied at a rate of 1114.5 g (AI)/ha. Each treatment in Field 2 was applied to 10 × 4 m plots which were replicated 4 times and arranged in a RCB design. Two blocks of treatments were applied to ‘Fontanelle 4435’ hybrid field corn plants and 2 blocks of treatments were planted to ‘Fontanelle 6240’ hybrid field corn plants. Treatments in both fields were evaluated 13 Jul by rating washed roots, using the 1-6 Iowa Root Damage Rating Scale, of 4 plants from each replicate.


1994 ◽  
Vol 19 (1) ◽  
pp. 211-211
Author(s):  
R. C. Seymour ◽  
J. B. Campbell ◽  
R. J. Wright

1995 ◽  
Vol 20 (1) ◽  
pp. 178-178
Author(s):  
R. C. Seymour ◽  
J. B. Campbell ◽  
R. J. Wright

Abstract Insecticides were applied to suppress larval rootworm populations in 2 fields in west central NE. Both fields located at the University of Nebraska West Central Research and Extension Center were composed of Cozad silt loam soils.


2021 ◽  
pp. 22-25
Author(s):  
Л.М. Поддымкина ◽  
Н.В. Бовыкина ◽  
Л.А. Дорожкина ◽  
Г.Е. Ларина

При выращивании томата в блочных теплицах комбината «Тепличный» (г. Владимир) в летне-осеннем обороте с использованием капельного полива дана оценка эффективности борьбы с белокрылкой и паутинным клещом химическим и биологическим методами. Для снижения численности белокрылки использованы следующие инсектициды: Моспилан (ацетамиприд, 20 г/кг), норма расхода 1,5 кг/га; Пленум (пиметрозин, 500 г/кг), 0,5 кг/га; Мовенто Энерджи (спиротетрамат + имидаклоприд), две обработки по 0,7 л/га; против паутинного клеща проведены три обработки Фитовермом (аверсектин С), 3 л/га. В биологической защите для подавления тепличной белокрылки и паутинного клеща применяли выпуск агентов биологической борьбы: в первой схеме макролофуса и фитосейулюса и во второй – энкарзии и фитосейулюса. Выпуск энкарзии проведен четыре раза, из расчета 1,5 экз/лист (трехкратный выпуск) и 1 экз/лист (однократный выпуск). Заселение растений хищным клопом макролофус проведено два раза из расчета 10000 экз/га. Хищного клеща фитосейулюса размещали локально в очаги скопления паутинного клеща (500 экз/га). Биологическую эффективность пестицидов и хищных насекомых оценивали по численности вредных объектов до обработки и через 3, 5 и 7 суток после обработки по общепринятым методикам. Против болезней во всех схемах защиты использовали для подавления корневых гнилей Планриз, 5 л/га и Превикур Энерджи (пропамокарб + фосэтил), 3 л/га, от фитофтороза и альтернариоза – Ордан (хлорокись меди + цимоксанил), 2,5 кг/га, Квадрис (азоксистробин), 1,2 л/га. Результаты учета численности вредителей до и после обработки показали, что биологическая эффективность использования хищных насекомых против белокрылки составляет 90–95% и против паутинного клеща – 78–80%, а инсектицидов – 76%. Эффективность биометода в борьбе с белокрылкой и клещом была выше, чем инсектицидов химической природы. Использование хищных насекомых позволило снизить объем применения пестицидов на 12,4 кг/га и увеличить сбор плодов на 18 и 9%. Прибыль от применения макролофуса и фитосейулюса составила 1,278 млн р. и от энкарзиии и фитосейулюса – 0,615 млн р. Assessment of the efficiency of controlling greenhouse whiteflies and spider mites with chemical and biological methods is given when using drip irrigation while growing tomatoes in block greenhouses of the «Teplichny» greenhouse complex (Vladimir) in summer-autumn. To control whiteflies, the following insecticides were used: Mospilan (acetamiprid, 20 g/kg), consumption rate 1.5 kg/ha, Plenum (pymetrozin, 500 g/kg), 0.5 kg/ha, Movento Energy (spirotetramat + imidacloprid), two treatments at 0.7 l/ha; 3 treatments with Phytoverm (aversectin C), 3 l/ha were carried out for spider mites. Within biological control, predatory and parasitic insects and mites were used to suppress greenhouse whiteflies and spider mites: first macrolophus and phytoseiulus, and then encarsia and phytoseiulus. Encarsia was used 4 times: at the rate of 1.5 spec/leaf (3 times) and 1 spec/leaf – fourth time. Plants were colonized by the predatory bug macrolophus twice at the rate of 10000 spec/ha. Predatory mite phytoseiulus was placed locally in the spider mite infestation (500 spec/ha). The biological efficiency of pesticides and predatory insects was assessed by the number of harmful objects before the treatment and 3, 5 and 7 days after it according to generally accepted methods. In all protection schemes for disease control the following was used: Planriz, 5 l/ha and Previcur energy (propamocarb + fosethyl), 3 l/ha to suppress root rot; Ordan (copper oxychloride + cymoxanil), 2.5 kg/ha, Quadris (azoxystrobin), 1.2 l/ha to suppress phytophthora and alternaria. The results of counting the pest number before and after the treatment showed that the biological efficiency of using predatory insects for whiteflies was 90–95%, for spider mites – 78–80%, and 76% when using insecticides. Thus, the biological method efficiency of controlling whiteflies and spider mites was higher than that of chemical insecticides. Predatory insects made it possible to reduce the amount of pesticide application by 12.4 kg/ha and increase the harvest by 18 and 9%. The profit from the use of macrolophus and phytoseiulus amounted to 1.278 million rubles and from encarsia and phytoseiulus – 0.615 million rubles.


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