IMPACT OF INSECT PEST ON YIELD OF RICE: CASE OF VARIETIES IR 46 AND NERICA 3 IN AGROECOSYSTEME OF MAGA FAR NORTH OF CAMEROON

2017 ◽  
Vol 6 (2) ◽  
pp. 11-29
Author(s):  
SADOU Ismaël ◽  
Keyword(s):  
2018 ◽  
Vol 3 (5) ◽  
pp. 1897-1905
Author(s):  
SADOU Ismaë ◽  
MADI ALI ◽  
WOIN Noé ◽  
DJONWANWE DJONWANWE ◽  
MBONGAYA Samy Eware ◽  
...  
Keyword(s):  

Author(s):  
O. E. Bradfute

Maize rayado fino virus (MRFV) causes a severe disease of corn (Zea mays) in many locations throughout the neotropics and as far north as southern U.S. MRFV particles detected by direct electron microscopy of negatively stained sap from infected leaves are not necessarily distinguishable from many other small isometric viruses infecting plants (Fig. 1).Immunosorbent trapping of virus particles on antibody-coated grids and the antibody coating or decoration of trapped virus particles, was used to confirm the identification of MRFV. Antiserum to MRFV was supplied by R. Gamez (Centro de Investigacion en Biologia Celular y Molecular, Universidad de Costa Rica, Ciudad Universitaria, Costa Rica).Virus particles, appearing as a continuous lawn, were trapped on grids coated with MRFV antiserum (Fig. 2-4). In contrast, virus particles were infrequently found on grids not exposed to antiserum or grids coated with normal rabbit serum (similar to Fig. 1). In Fig. 3, the appearance of the virus particles (isometric morphology, 30 nm diameter, stain penetration of some particles, and morphological subunits in other particles) is characteristic of negatively stained MRFV particles. Decoration or coating of these particles with MRFV antiserum confirms their identification as MRFV (Fig. 4).


Crisis ◽  
2019 ◽  
Vol 40 (6) ◽  
pp. 422-428 ◽  
Author(s):  
Chris Rouen ◽  
Alan R. Clough ◽  
Caryn West

Abstract. Background: Indigenous Australians experience a suicide rate over twice that of the general population. With nonfatal deliberate self-harm (DSH) being the single most important risk factor for suicide, characterizing the incidence and repetition of DSH in this population is essential. Aims: To investigate the incidence and repetition of DSH in three remote Indigenous communities in Far North Queensland, Australia. Method: DSH presentation data at a primary health-care center in each community were analyzed over a 6-year period from January 1, 2006 to December 31, 2011. Results: A DSH presentation rate of 1,638 per 100,000 population was found within the communities. Rates were higher in age groups 15–24 and 25–34, varied between communities, and were not significantly different between genders; 60% of DSH repetitions occurred within 6 months of an earlier episode. Of the 227 DSH presentations, 32% involved hanging. Limitations: This study was based on a subset of a larger dataset not specifically designed for DSH data collection and assesses the subset of the communities that presented to the primary health-care centers. Conclusion: A dedicated DSH monitoring study is required to provide a better understanding of DSH in these communities and to inform early intervention strategies.


2003 ◽  
pp. 108-116
Author(s):  
A. Bykov

According to the legal norms of the Russian Federation in the ownership, usage and disposal of natural resources the author analyses interaction between natural resources users and local authorities. The interaction is based upon ecological and economic factors, which cause the peculiarities of requirements put before natural resource users in the Far North. The strategic directions of resource saving economic development of these regions are considered.


Author(s):  
A.J. Cresswell

This paper, as well as being a testimonial to the benefit the writer has received from the Grassland Association, shows how the knowledge of scientists has been used to increase lucerne seed yields by methods of growing resistant cultivars especially for seed production as opposed to growing for hay, silage or grazing. It shows how new cultivars can be multiplied quickly by growing two crops in one year, one in each hemisphere, by using low seeding rates, wide plant spacing and very good weed control. Increased flowering of the crop has been achieved by the use of boron and the choice of time of closing; better pollination has been achieved by the use of more efficient bees - two varieties of which have been imported from North America. Weed and insect pest control and the use of a desiccant at harvest are contributing to a four-fold increase in seed yield, which should double again soon,


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 (1) ◽  
pp. 395-407
Author(s):  
Solozhenkin P.M. ◽  
◽  
Kushakov S.T. ◽  
Kovalev V.N. ◽  
◽  
...  

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