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Impact of Site Preparation on Wind Resistance of Young Pinus radiata
Item type: Journal Article • Journal: South African Forestry Journal • Authors: J.B. Zwolinski --- , D. G.M. Donald --- Forestry Faculty, W.H. Groenewald --- Division of Forest Science and Technology,Young trees were damaged by winds blowing at 39 m/s speed in the southern Cape Province. The frequency and the extent of wind damage was investigated in an establishment experiment comprising four methods of soil cultivation, two levels of weed... -
Plant population and cultivar effects on yield losses caused by the maize stalk borer, Busseola fusca (Lepidoptera: Noctuidae)
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J. B.J van Rensburg --- Summer Grain Centre, Republic of South Africa M.C. Walters --- , Republic of South Africa J.H. Giliomee --- Department of Entomology, Republic of South AfricaMaize plants were subjected to controlled infestations of Busseola fusca (Fuller). Variations in inter- and intra- row spacing had a pronounced influence on the damage caused by the pest. Both the rates of dispersal and the survival of the larvae... -
Abnormalities of the growth point and ear of barley caused by 2,4-dichlorophenoxy acetic acid
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J.W. Loubser --- Department of Agriculture and Water Supply, Republic of South Africa A. L.P. Cairns --- , Republic of South AfricaTreatment of barley plants with 2,4-D, when the main tiller apical meristem was in the late vegetative or double ridge stage, resulted in the production of various abnormalities including missing spikes, branched spikes, whorls of spikelets and paired spikelets instead... -
Nature and importance of subterranean insect damage to pre-harvest groundnuts
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C.F. van Eeden --- , Republic of South Africa J. B.J. van Rensburg --- Summer Grain Centre, Republic of South Africa T. C. de K. van der Linde --- Department of Zoology and Entomology, Republic of South AfricaThe nature and importance of insect damage to subterranean pre-harvest groundnuts were determined by regular sampling in commercial groundnut fields. Five categories of damage are described, viz. damage to newly planted seed, pegs, immature pods, mature pods and kernels. Both... -
The effect of pod scarification by soil inhabiting insects on the quality of groundnuts (Arachis hypogaea L.)
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C.F. van Eaden --- , Republic of South Africa J. B.J. van Rensburg --- Summer Grain Centre, Republic of South Africa T. C. de K. van der Linde --- Department of Zoology and Entomology, Republic of South AfricaThe effect of pod scarification by soil insects on the yield and quality of groundnuts was determined at thirty localities in the Highveld Region of South Africa. Subsamples of superficially damaged pods and sound pods were shelled separately, the kernels... -
The role of insect damage in the colonization of groundnut (Arachis hypogaea L.) pods by fungi
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C.F. van Eeden --- , Republic of South Africa J. B.J van Flensburg --- Summer Grain Centre, Republic of South Africa T. C. de K. van der Linde --- Department of Zoology and Entomology, Republic of South AfricaThe incidence of fungal infection in insect-damaged and healthy pods and the resultant colonization of kernels was determined from commercial fields at four localities over a period of two seasons. Based on number of colonies per 100 plates, the order... -
Germination of South African soya bean seed lots
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: B. Hamman --- Department of Botany, Republic of South Africa G. Koning --- Department of Botany, Republic of South Africa H.A. van de Venter --- Department of Botany, Republic of South AfricaA survey of the germination performance of some South African soya bean [Glycine max (L.) Merrill.] cultivars, produced at different localities, was conducted. Seeds were harvested from two early-maturing (Columbus and Crawford), two intermediate-maturing (Prima and Highveld Top), and two... -
Influence of harvest maturity on quality of cold stored Vitis vinifera L. cv. ‘Thompson Seedless’ and ‘Red Globe’ table grapes, with special reference to berry split
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: D.A. Burger --- , South Africa M.A. Taylor --- , South Africa G. Jacobs --- Department of Horticultural Science, South Africa M. Huysamer --- Department of Horticultural Science, South AfricaEffect of harvest maturity on quality of Thompson Seedless' and ‘Red Globe’ table grapes after cold storage at −0.5°C and a subsequent shelf life was investigated. Berry split decreased significantly for grapes harvested at more advanced maturities. By harvesting ‘Thompson... -
Yield retention of resistant wheat cultivars, severely infested with Russian wheat aphid, Diuraphis noxia (Kurdjumov), in South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: VickiL. Tolmay --- , South Africa CS van Deventer --- Department of Plant Breeding, South AfricaRussian wheat aphid, Diuraphis noxia (Kurdjumov), has been a serious pest of wheat in South Africa since 1978. Wheat producers observed that resistant cultivars, developed for control of this aphid, differed in resistance and questioned whether insecticide treatment would be... -
Sublethal effects of manganese on the haematology and osmoregulation of Oreochromis mossambicus after acute exposure
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: I Barnhoorn JHJ van VuurenOreochromis mossambicus were exposed for 96 hours to sublethal manganese concentrations in a continuous flow-through system. The sublethal concentrations were determined from the LC50 value of manganese (1.723mg/l), which included a 10% (172.3mg/l), 15% (259.8mg/l) and 20% (345.6mg/l) concentration of... -
Does soil compaction on harvesting extraction roads affect long-term productivity of Eucalyptus plantations in Zululand, South Africa?
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: Colin W. Smith --- ,The effect ofsoil compaction on the growth of Eucalyptusgrandis and two clonal hybrids (Eucalyptus grandis x urophylla (E. gxu) and Eucalyptus grandis x camaldulensis (E. gxc)) was evaluated on harvesting extraction roads at three sites in the Zululand region ofKwaZulu-Natal... -
The effect of Sirex noctilio infestation and fire damage on the chemical composition of South African-grown Pinus patula pulpwood
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: M du Plessis NJ le Roux S Gardner-Lubbe JPJ Swart (Change Le to le) T RypstraThe infection and association between the wood wasp Sirex noctilio and the fungus Amylostereum areolatum is responsible for large-scale tree mortality in the Midlands of the KwaZulu-Natal province in South Africa. An exploratory investigation on the effect of the infestation... -
Value and impact of massive blood transfusion protocols in the management of trauma patients
Item type: Journal Article • Journal: Southern African Journal of Anaesthesia and Analgesia • Authors: MDC Ortega-Gonzalez --- Department of Anaesthesia, BI Monzon-Torres --- Department of Trauma Directorate, Division of Surgery,Trauma-related injuries are the second leading cause of death and disability in South Africa. The traditional approach to surgery and resuscitation of severely injured patients has undergone change over the past 10 years. New concepts like damage control surgery and... -
The influence of fire on rodent abundance at the N’washitshumbe enclosure site, Kruger National Park, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: D.N. MacFadyen --- Mammal Research Institute, Department of Zoology and Entomology, South Africa N.L. Avenant --- Department of Mammalogy, South Africa M. van der Merwe --- Mammal Research Institute, Department of Zoology and Entomology, South Africa G.J. Bredenkamp --- Department of Plant Sciences, South AfricaThe relative population numbers of rodents were studied in nine habitats in and outside the N’washitshumbe enclosure site, Kruger National Park, before and after burning the firebreaks that surround the enclosure. Trap success was exceptionally high, and the field work... -
Space radiation environment of ALSAT-2 and its degradation effect on InGaP/InGaAs/Ge solar cells
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Nadjima Benkara Mohammed --- Department of Sciences and Techniques, Faculty of Sciences and Technology, Algeria Souaad Benkara Mahammed --- Department of Electrical and Computer Engineering, Faculty of Engineering, MalaysiaSurrounding the earth, and throughout outer space, significant levels of radiation particles exist. These particles include protons, electrons, heavy ions, and other forms of radiation. Different regions are known to contain different amounts of various types of particles with different... -
Effect of residue management and fertiliser application on the productivity of a Eucalyptus hybrid and Acacia mangium planted on sloping terrain in northern Vietnam
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Nguyen Van Bich --- Tasmanian Institute of Agriculture, University of Tasmania, Australia Daniel Mendham --- CSIRO Land and Water, Australia Katherine J Evans --- Tasmanian Institute of Agriculture, University of Tasmania, Australia Tran Lam Dong --- Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Vietnam Vo Dai Hai --- Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Vietnam Hoang Van Thanh --- Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Vietnam Caroline L Mohammed --- Tasmanian Institute of Agriculture, University of Tasmania, AustraliaForest plantation growers in Vietnam commonly burn residues after harvesting and often apply suboptimal amounts of nutrients during plantation establishment. We examined whether the retention of forest residue, and application of phosphorus fertiliser at higher rates, can increase rates of... -
The diet of spotted-necked otters foraging in trout-stocked waters in Mpumalanga, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: Rowan K Jordaan --- , South Africa Michael J Somers --- , South Africa Grant Hall --- , South Africa Trevor McIntyre --- , South AfricaHuman-wildlife conflict is likely to increase as urbanisation increases. African clawless otters, Aonyx capensis, and spotted-necked otters, Hydrictis maculicollis, are illegally persecuted for their perceived role in reducing trout in artificially stocked habitats in South Africa. The diet of African... -
Prevalence, population structure and burrow morphology of the kelp-boring amphipod Sunamphitoe roberta
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MJ Wilcox --- , South Africa J Landschoff --- , South Africa CL Griffiths --- , South AfricaThe recently described amphipod Sunamphitoe roberta lives only on the kelp Ecklonia maxima, where it excavates slit-like burrows along the distal margins of thicker primary fronds. Oval chambers along the bases of these slits may represent feeding areas. As burrowing... -
Foliar fungicides provide chemical control of Fusarium head blight of wheat in South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Gerhardus J van Coller --- , South Africa Frederik J Kloppers --- , South Africa Vicky M Coetzee --- , South Africa Toinette van Rooyen --- , South Africa Lindy J Rose --- , South Africa Sandra C Lamprecht --- , South Africa Altus Viljoen --- , South AfricaChemical control of a yield-limiting, quality-reducing wheat disease like Fusarium head blight (FHB) is an important management strategy; however, no fungicides are registered against it in South Africa. The aim of this study was to determine foliar fungicides and seed... -
Impact of interactions between common bottlenose dolphins and purse-seiners in the Moroccan Mediterranean region: case study in the Al Hoceima fishing grounds
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Keznine --- Abdelmalek Essaâdi University, Morocco B Mghili --- Abdelmalek Essaâdi University, Morocco H Awadh --- Abdelmalek Essaâdi University, Morocco M Analla --- Abdelmalek Essaâdi University, Morocco M Aksissou --- Abdelmalek Essaâdi University, MoroccoThis study examines the effect of common bottlenose dolphins Tursiops truncatus on the purse-seine fishery for small pelagic fishes in the Mediterranean Sea and the economic consequences thereof. The investigation focused on the fleet registered at the port of Al...