scholarly journals Effect of the Insect Infestation by Myzus persicae and Trialeurodes vaporariorum on the Annual Production of Strawberry Under Glasshouse Conditions

Author(s):  
Gamila, Heikal ◽  
Heba, Alghnam ◽  
Salem, Hagar ◽  
Emam S
Author(s):  
G.J.Rys I.M. Ritchie ◽  
R.G. Smith ◽  
N.A. Thomson ◽  
G. Crouchley ◽  
W. Stiefel

The performance of 'Grasslands Matua' prairie grass (Bromus catharticus) was compared with perennial ryegrasses under mowing or grazing in three trials conducted in the southern North Island. Production of Matua under mowing at Flock House and Waimate West was 13% and 19% greater than G.4708 and Nui ryegrass, respectively, with the extra production contributed in summer and winter. At Masterton no difference between Matua and Ariki ryegrass production occurred under grazing. A 31% increase in annual production was recorded for both Matua and G.4708 swards receiving N, compared with those sown with white clover, with the annual yield of G.4708 receiving N similar to Matua receiving no N. Less frequent defoliation increased production of Matua swards by 17% and the Matua component by 38%. Production of Nui in comparison with Matua swards was 14% lower under frequent and 9% lower under infrequent defoliation. Similar production was recorded from red clover under frequent, and infrequent defoliation for both Nui and Matua swards. A 48% lower yield of white clover occurred under infrequent defoliation of Matua swards. At Masterton a higher incidence of goitre in newborn lambs, accompanied by a 12% lower lamb liveweight at weaning, occurred on Matua- compared with Ariki-based swards. Aspects of seasonal production, fertility response, management, and animal health are discussed.


2020 ◽  
Vol 31 (1) ◽  
pp. 24-35 ◽  
Author(s):  
Somiahnadar Rajendran

Insects are a common problem in stored produce. The author describes the extent of the problem and approaches to countering it. Stored products of agricultural and animal origin, whether edible or non-edible, are favourite food for insect pests. Durable agricultural produce comprising dry raw and processed commodities and perishables (fresh produce) are vulnerable to insect pests at various stages from production till end-use. Similarly, different animal products and museum objects are infested mainly by dermestids. Insect pests proliferate due to favourable storage conditions, temperature and humidity and availability of food in abundance. In addition to their presence in food commodities, insects occur in storages (warehouses, silos) and processing facilities (flour mills, feed mills). Insect infestation is also a serious issue in processed products and packed commodities. The extent of loss in stored products due to insects varies between countries depending on favourable climatic conditions, and pest control measures adopted. In stored food commodities, insect infestation causes loss in quantity, changes in nutritional quality, altered chemical composition, off-odours, changes in end-use products, dissemination of toxigenic microorganisms and associated health implications. The insects contribute to contaminants such as silk threads, body fragments, hastisetae, excreta and chemical secretions. Insect activity in stored products increases the moisture content favouring the growth of moulds that produce mycotoxins (e.g., aflatoxin in stored peanuts). Hide beetle, Dermestes maculatus infesting silkworm cocoons has been reported to act as a carrier of microsporidian parasite Nosema bombycis that causes pebrine disease in silkworms. In dried fish, insect infestation leads to higher bacterial count and uric acid levels. Insects cause damage in hides and skins affecting their subsequent use for making leather products. The trend in stored product insect pest management is skewing in favour of pest prevention, monitoring, housekeeping and finally control. Hermetic storage system can be supplemented with CO2 or phosphine application to achieve quicker results. Pest detection and monitoring has gained significance as an important tool in insect pest management. Pheromone traps originally intended for detection of infestations have been advanced as a mating disruption device ensuing pest suppression in storage premises and processing facilities; pheromones also have to undergo registration protocols similar to conventional insecticides in some countries. Control measures involve reduced chemical pesticide use and more non-chemical inputs such as heat, cold/freezing and desiccants. Furthermore, there is an expanding organic market where physical and biological agents play a key role. The management options for insect control depend on the necessity or severity of pest incidence. Generally, nonchemical treatments, except heat, require more treatment time or investment in expensive equipment or fail to achieve 100% insect mortality. Despite insect resistance, environmental issues and residue problems, chemical control is inevitable and continues to be the most effective and rapid control method. There are limited options with respect to alternative fumigants and the alternatives have constraints as regards environmental and health concerns, cost, and other logistics. For fumigation of fresh agricultural produce, new formulations of ethyl formate and phosphine are commercially applied replacing methyl bromide. Resistance management is now another component of stored product pest management. In recent times, fumigation techniques have improved taking into consideration possible insect resistance. Insect control deploying nanoparticles, alone or as carriers for other control agents, is an emerging area with promising results. As there is no single compound with all the desired qualities, a necessity has arisen to adopt multiple approaches. Cocktail applications or combination treatments (IGRs plus organophosphorus insecticides, diatomaceous earth plus contact insecticides, nanoparticles plus insecticides/pathogens/phytocompounds and conventional fumigants plus CO2; vacuum plus fumigant) have been proved to be more effective. The future of store product insect pest management is deployment of multiple approaches and/or combination treatments to achieve the goal quickly and effectively.


2018 ◽  
Vol 1 (3) ◽  
pp. 176-181 ◽  
Author(s):  
E. Tettey

Under-fermentation of cocoa beans produces purple beans. The fermentation period is 6 to 7 days but some cocoa farmersunder-ferment their cocoa beans leading to the development of purple cocoa beans. This study determined the impact of insectinfestation on stored purple cocoa beans. Wet cocoa beans were fermented for 1, 2, 3, 4 and 5 days to produce the purple beans.Ephestia cautella and Tribolium castaneum, both singly and in combination, were introduced into the cocoa beans and storedfor different (30, 60, 90 and 120 days) period. Insect population, percentage weight loss and the contaminants produced bythese insects were determined. Cocoa beans infested with E. cautella alone had the highest population of 297.0 ± 22.7. Beansfermented for 3 days had the lowest insect population both singly and in combination after 120 days of storage. The highestpercentage weight loss was recorded in cocoa beans fermented for one day (10.1 ± 1.87%) and 4 days (10.1 ± 8.74%). T.castaneum did not cause much damage to the cocoa beans but E. cautella alone caused significant damage to stored cocoabeans. Insect infestation and poor fermentation contribute significantly to the reduction in quality of cocoa beans.


Author(s):  
R.A. Bagrov ◽  
◽  
V.I. Leunov

The mechanisms of transmission of potato viruses from plants to aphid vectors and from aphids to uninfected plants are described, including the example of the green peach aphid (Myzus persicae, GPA). Factors affecting the spreading of tuber necrosis and its manifestation on plants infected with potato leafroll virus (PLRV) are discussed. Recommendations for PLRV and GPA control in the field are given.


Author(s):  
Тамара Алексеевна Шелабина ◽  
Марина Николаевна Берим

Существенным элементом в комплексе специальных и агротехнических приемов, направленных на ограничение распространения вирусной инфекции, является мониторинг численности, динамики и видового состава тлей, мигрирующих в посадках оригинального картофеля. Двухлетний мониторинг (2016 – 2017 гг.) на опытных полях Гатчинского района Ленинградской области проведен с использованием желтых водных ловушек Мёрике. Изучены количество тлей, сроки их миграции на посадки картофеля, сроки наступления пика численности. Наибольшее влияние на насекомых оказывала среднесуточная температура воздуха. За сезон наблюдений отловлено: в 2016 г. — 481 крылатая особь 31 вида, в 2017 г. — 131 особь 30 видов. Доля возможных переносчиков вирусов картофеля от общего числа зарегистрированных крылатых тлей составила в 2016 г. 14,8 %, в 2017 г. — 32,8 %. Оценка скрытой зараженности вирусной инфекцией (MBK, YBK вирусы) методом ИФА в 2015 – 2017 гг. показала, что на растениях картофеля сорта Ломоносовский скрытая зараженность составила 2,6 – 7,3 %, сорта Чародей — 1,9 – 13,3 %, сорта Невский — 0,8 – 10,5 %, сорта Романо — 4,1 – 9 %. Из известных переносчиков вирусов картофеля в оба года в энтомологических сборах с сосудов отмечены Aphis nasturtii — 6 – 12,2 %, Aphis fabae — 7,2 – 4,6 % от общего числа отловленных; Myzus persicae (13 %) в составе мигрирующей генерации тлей отмечены только в дождливом и прохладном 2017 г. В прогностических целях желательно пользоваться в регионе также данными со всасывающей ловушки, поскольку появление в ней насекомых отмечено на 10 – 12 дней раньше, чем на полях.


2000 ◽  
Vol 151 (11) ◽  
pp. 417-424 ◽  
Author(s):  
Ernst Zürcher

Ancient forest utilization regulations regarding felling dates and wood use are compared to the moon cycles. Furthermore, moon-phase related investigations with regard to germination behaviour, insect infestation and durability of the wood are presented.


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