Agriculture

Agriculture Research Papers/Topics

Factors influencing grafted mango (Mangifera indica L.) production in Matinyani division, Kitui county

Abstract: v ABSTRACT Mango ( Mangifera indica L.) fruit is produced and consumed globally, regionally, and locally. The fruit is a potential sou rce of essential nutrients including potassium, phosphorous, magnesium and is an excellent source of vitamin A and C . Mangoes can also be sold to earn income . However, most smallholder mango farmers in Matinyani Sub - county experience lack of clean planting materials, ina dequate production technolo gies , inadequate mango varieties with long pro...

Prioritisation of emerging chemical pollutants in South African water resources

Abstract: Emerging chemical pollutants (ECPs) are defined as new chemicals which do not have a regulatory status, but which may have an adverse effect on human health and the environment. Sources and environmental pathways of these ECPs have been increasingly associated with waste and wastewaters arising from industrial, agricultural and municipal activities. The ECPs of current concern include a wide range of compounds including polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocar...

Factors affecting the occurrence and abundance of the Natal Cascade frog Hadromophryne natalensis at Mariepskop South Africa

Abstract: Amphibians have long been recognized as excellent indicators of both biological and ecological health of ecosystems, as they occupy many habitats and environments and have a diverse range of impacts on their immediate environments. It is thus important to investigate the critical habitat requirements, as well as the preferred environmental variables that are associated with different amphibian species in order to provide insight into conservation and management plans, and to predic...

The Distribution of cetaceans off the coast of South Africa and South West Africa / Namibia

Abstract: Thirty - seven species of cetacean are recorded from southern African waters. Four thousand, five hundred and thirty - seven records of approximately 60 000 cetaceans were analysed to defme distribution patterns of these species, including dedicated sightings (both scientific and commercial), incidental sightings, commercial catches and specimens. Records of dedicated scientific sightings and incidental sightings were analysed by water depth, sea surface temperature and salinity an...

Demographic responses to changes in conservation management : a case study on elephants in the Kruger National Park

Abstract: Conservation management approaches for elephants in southern Africa, and particularly in the Kruger National Park, have changed. Recently, Kruger’s managers adapted their approach from artificially manipulating elephant numbers to reinstating and embracing densitydependent processes that could limit or regulate the elephant population. However, few studies have evaluated whether changes in Kruger’s elephant management approach were effective in achieving the desired outcomes. T...

Effects of elevated temperature and water-deficit stress on the potato aphid Macrosiphum euphorbiae (Thomas) (Hemiptera : Aphididae) and its parasitoid Aphidius ervi Haliday (Hymenoptera

Abstract: Global climate change is expected to increase average surface temperatures by 1.5 to 4.5 °C by the end of the 21st century. Major variation in climatic conditions is predicted to occur, including more frequent droughts and heat waves as well as higher mid-summer temperatures. Water-deficit stress may lead to increased nitrogen levels in plants, which in turn may increase their suitability for insect herbivores. In addition, the higher nutritional quality of the insect herbivore di...

Canthonini (Scarabaeidae: Scarabaeinae) of Gondwana : comparison of male genitalia evolutionary trends and phylogeny

Abstract: The current study is about the evolution and the morphology of dung beetles, subfamily Scarabaeinae. The study includes the systematics of the tribe Canthonini and an exhaustive analysis of the morphological variation of male genitalia including species from the 11 tribes of the subfamily, mainly Canthonini, Ateuchini, Scarabaeini and Coprini. With the aim to go deep in the phylogenetic relationships of the tribe Canthonini, the largest of the subfamily Scarabaeinae, with 91 genera...

Ecology and life history of the Vlei Rat, Otomys Irroratus (Brants, 1827), on the Van Riebeeck Nature Reserve, Pretoria

Abstract: The ecology and life history of the vlei rat, Otomys irroratus (Brants, 1827), were studied in a population on the Van Riebeeck Nature Reserve near Pretoria. Two main procedures were used to collect the basic information and material for the project. First, a permanent live-trapping grid was established where 333 animals were captured, marked, released, and recaptured over a period of 26 months, Second, snap-trapping and live-trapping were conducted elsewhere in the study area for ...

Behavioural ecology and conservation biology of ground pangolins Smutsia temminckii in the Kalahari Desert

Abstract: Ground pangolins Smutsia temminckii are inconspicuous, mainly nocturnal mammals that occur at low population densities. As a result, there is scant information available on the ecology and physiology of this species. To date the handful of studies focussing on this species were centred in the mesic eastern regions of its range, with no attention being given to ecological and biological traits in arid environments. To address these data shortfalls, a study was undertaken in the Kala...

Genomics of West Nile viruses from South Africa

Abstract: West Nile Virus (WNV) forms part of the Japanese encephalitis serocomplex in the genus Flavivirus, family Flaviviridae. This enveloped positive single-stranded RNA (+ssRNA ) virus is the etiological agent of West Nile fever, and in more severe cases WNV neuroinvasive disease, in both humans and animals. WNV is distributed worldwide and is phylogenetically classified into five distinct lineages. The WNV genome is ~11 Kb in length and encodes a single open reading frame (ORF) that is...

Conservation biology of the giant bullfrog, Pyxicephalus adspersus (Tschudi, 1838)

Abstract: The giant bullfrog, Pyxicephalus adspersus, is a large, explosive-breeding anuran from southern Africa, which spends most of the year buried in a state of torpor. In South Africa this species is considered to be Near-Threatened by habitat loss and other factors, especially in the densely human populated Gauteng Province. The aim of this thesis was to obtain essential outstanding information about the ecology of P. adspersus to contribute towards improved conservation management of ...

Prevalence of parasites and diseases in the African honeybee (Apis mellifera scutellata Lepeletier) : with a particular focus on Varroa destructor

Abstract: The status of honeybee pathogens and parasites in the Gauteng region of South Africa was examined by collecting adult honeybee and worker brood samples from 13 Apis mellifera scutellata apiaries. The prevalence of pathogens and parasites were compared per season between sedentary (permanently stationed colonies) and migratory (transportation of colonies for pollination purposes) apiaries. Honeybee pathogens (Acute bee paralysis virus (ABPV), Black queen cell virus (BQCV), Chronic b...

Beekeeping and forest conservation : a case study of Arabuko Sokoke Forest, Kenya

Abstract: Tropical forests are shrinking worldwide. This is mainly because human beings, in a bid to obtain a livelihood, have overexploited their timber and non-timber products. At Arabuko Sokoke Forest (ASF), Kenya, community-driven conservation projects have been initiated, to ensure that the people can draw a livelihood from this vital ecosystem without destroying it. Among the projects involved is apiculture in the vicinity of the forest. Although some studies have been carried out on v...

Water column usage and environmental determinants in southern elephant seals from Marion Island

Abstract: Southern elephant seals (Mirounga leonina) are relatively common top predators and major consumers within the Southern Ocean. This study aimed to describe the at-sea behaviour of a small population of southern elephant seals at Marion Island and to place this behaviour into an ecological and evolutionary context. Calculations of life-time habitat use for animals from this population revealed that seals spent an average of 77.59% of their lives diving at sea, 7.06% at the sea surfac...


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