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Sterile Lanterna camara: fact or theory
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J.J. Spies --- Department of Agriculture and Water Supply, Republic of South Africa Henriette du Plessis --- Department of Agriculture and Water Supply, Republic of South AfricaAttempts are being made to legalize the sale of ‘sterile’ Lantana camara varieties in South Africa. Several so-called sterile varieties have been investigated cytogenetically. All these. plants proved to be triploids.(2n = 33). A mechanism exists through which an unexpectedly... -
The influence of temperature and boron on pollen germination in Mangifera indica L.
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Esmé de Wet --- , Republic of South Africa P.J. Robbertse --- , Republic of South Africa H.T. Groeneveld --- Department of Statistics/Plant Production, Republic of South AfricaFruit set in the mango (Mangifera indica L.) cultivar ‘Haden’ is exceptionally low. In an effort to determine the reason for this phenomenon, the influences of temperature and application of boron on pollen germination and the effectiveness of cross- versus... -
Effect of triadimefon on fruit set and seed development of ‘Starking Delicious’ apple
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: G. Jacobs --- Department of Horticulture, Republic of South Africa L. Gouws --- Department of Horticulture, Republic of South Africa D.K. Strydom --- Department of Horticulture, Republic of South AfricaSpray applications of triadimefon (TDF) (1–4 chlorophenoxy 3,3 dimethyl 1–1-H-1,2,4 triazol 1-yl-2 butanone) (5% W.P.) at 100 mg dm−3 active ingredient at full bloom and pre- and/or post-full bloom on ‘Starking Delicious’ apple trees (Malus domestica Borkh.) increased fruit set... -
The importance of certain insects as pollinators of sunflower (Helianthus annuus L.)
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.P. du Toit --- , Republic of South AfricaThis study reports the effects of Apis mellifera L. (honeybees), Astylus atromaculatus Blanchard (spotted maize beetles), Heliothis armigera Hübner (American bollworm larvae) and Musca domestica L. (house flies) on seed set in commercial sunflower. The pollination efficiency of these insects... -
Diversity, abundance and behaviour of diurnal insects on flowering capitula of commercial sunflower in the Transvaal
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.P. du Toit --- Apicultural Unit, Republic of South Africa E. Holm --- Department of Entomology, Republic of South AfricaSunflower, Helianthus annuus L., is an insect-pollinated crop and the different insect taxa visiting the flowering head play a role of greater or lesser importance in cross-pollination. Species diversity, abundance and behaviour of insects visiting commercial sunflower during flowering are... -
Pollination activity and behaviour of honeybees (Apis mellifera L.) in commercial sunflower in the Transvaal
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.P. du Toit --- , Republic of South Africa E. Holm --- Department of Entomology, Republic of South AfricaHoneybee foraging activity in commercial sunflower fields was studied at Settlers, 100 km north of Pretoria. Foraging activity, which was studied by means of the conventional strip count method, commenced after sunrise and reached a peak of 38 foragers per... -
The effect of boron levels in nutrient solutions on fruit production and quality of greenhouse tomatoes
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J.N. Smit --- Department of Agronomy, Republic of South Africa N. J.J. Combrink --- Department of Agronomy, Republic of South AfricaInsufficient fruit set of tomatoes owing to poor pollination in low cost greenhouses is a problem in South Africa, as bumblebee pollinators may not be imported. Since sub-optimum boron (B) levels may also contribute to fruit set problems, this aspect... -
Controlled Pollination in Pinus Patula: Constraints and Possible Solutions
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: C. Bester --- , L. H.C. van der Merwe --- , J.L. Malema --- ,Pinus patula is the most important commercial pine species grown in southern Africa and it is, therefore, very important to have well developed breeding and production strategies for this species. Strategies which have been developed for SAFCOL's breeding programme include... -
Sunbirds hover at flowers of Salvia and Lycium
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Petra Wester --- Department of Botany and Zoology, South AfricaSunbirds usually perch when visiting flowers for nectar and only rarely hover. Except for three studies of sunbirds visiting introduced plants in South Africa and India as well as a native plant in Cameroon, there have been no quantitative studies... -
Relative success of self and outcross pollen after mixed- and single-donor pollinations in Eucalyptus grandis
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: TN Horsley --- School of Biological and Conservation Sciences, South Africa SD Johnson --- School of Biological and Conservation Sciences, South AfricaA previous observation that self-pollen tubes traversed the style at a slower rate than cross-pollen tubes in Eucalyptus grandis and E. urophylla suggested the presence of cryptic self-incompatibility (CSI) in these species. The aim of the present study was, with... -
Advances in reproductive biology and seed production systems of Eucalyptus: the case of Eucalyptus globulus
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: BM Potts MH McGowen DR Williams S Suitor TH Jones PL Gore RE VaillancourtEucalyptus globulus is the main eucalypt species grown in Australian plantations. The focus on seedling deployment systems, coupled with exploitation of large, open-pollinated base populations for breeding purposes over the last two decades, has required a detailed understanding of the... -
Nectar feeding by weavers (Ploceidae) and their role as pollinators
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Adrian JFK Craig --- Department of Zoology and Entomology, South AfricaReviews of nectar-feeding by birds initially focused on specialist nectarivores and ignored the role that more generalist feeders may play in plant pollination. Recent work has emphasised the range of bird species, both specialist and opportunistic, that feed on nectar... -
Interference competition between sunbirds and carpenter bees for the nectar of Hypoestes aristata
Item type: Journal Article • Journal: African Zoology • Authors: Robert Tropek --- Institute of Entomology, Biology Centre, Czech Academy of Sciences, Czech Republic Michael Bartoš --- University of South Bohemia, Czech Republic Eliška Padyšáková --- University of South Bohemia, Czech Republic Štěpán Janeček --- Academy of Sciences of the Czech Republic, Czech RepublicInterference competition for nectar sources has been repeatedly described between hummingbirds and various insects, but rarely recorded in other nectari-vorous birds. We observed aggressive behaviour by African sunbirds (Cinnyris reichenowi and Cinnyris bouvieri) defending the nectar plant Hypoestes aristata against... -
Sugar type and concentration preference of the Cape white-eye, Zosterops virens
Item type: Journal Article • Journal: African Zoology • Authors: Minke Witteveen --- University of KwaZulu-Natal, South Africa Mark Brown --- University of KwaZulu-Natal, South AfricaDifferences in nectar characteristics of bird-pollinated plants were originally attributed to whether the plant was pollinated by non-passerine hummingbirds or passerine nectarivores. Subsequently this has been refuted and it is now hypothesized that these differences reflect whether the plants are... -
Reproductive biology of the critically endangered tropical tree Talbotiella gentii
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Daniel Dompreh --- Department of Plant and Soil Science, UK Michael D Swaine --- Department of Plant and Soil Science, UK Christopher C Wilcock --- Department of Plant and Soil Science, UKTalbotiella gentii is a critically endangered caesalpiniaceous legume endemic to Ghana, restricted in distribution to the margins of the forest zone where there has been extensive fire damage in recent decades. It occurs as isolated, near-monospecific populations, some of which... -
Relative merits of using purified proteins and natural foods in studies of wildlife nutrition: the nitrogen requirements of a rodent pollinator
Item type: Journal Article • Journal: African Zoology • Authors: Ian G. Van Tets --- Department of Zoology, South Africa Ken Hutchings --- Department of Zoology, South Africa Susan Nicolson --- Department of Zoology, South AfricaAethomys namaquensis is a 60 g murid rodent that is an important pollinator of several Protea species in South Africa. We compared the nitrogen requirements of this species on two different protein sources: pollen and casein. Pollen is an important... -
Opportunistic breeding in the Cape spiny mouse (Acomys subspinosus)
Item type: Journal Article • Journal: African Zoology • Authors: P.A. Fleming [AN0001] S.W Nicolson --- Department of Zoology and Entomology, South AfricaThe relationship between Protea humiflora and its small mammal pollinators was investigated at the fynbos/karoo ecotone in the Riviersonderend Mountains, South Africa. Acomys subspinosus occurred in low densities at Jonaskop, with around 3.9 ± 2.0 (mean ± 1 S.D.) individuals/ha... -
Temporal partitioning of diurnal bird and nocturnal small mammal visitors to a winter flowering endemic succulent
Item type: Journal Article • Journal: African Zoology • Authors: Stephanie L Payne --- , South Africa Craig T Symes --- , South Africa Ed TF Witkowski --- , South AfricaFloral nectar is an important attractant and reward for visitors, and is often produced in synchrony with peak activity of pollinators. Aloe peglerae flowers in winter, and previous studies have shown that it is pollinated primarily by diurnal generalist birds,... -
Perception and adoption of artificial pollination technology in cocoa production: Evidence from Ghana
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Camillus Abawiera Wongnaa --- , Ghana Afrane Baffour Kyei --- , Ghana Isaac Akurugu Apike --- , Ghana Dadson Awunyo-Vitor --- , Ghana Raymond K. Dziwornu --- , GhanaThis study examined the perception and adoption of artificial pollination among cocoa farmers in Ghana. It used cross-sectional data collected from 206 cocoa farmers selected through multi-stage sampling technique. Descriptive statistics, Likert Scale and the Tobit regression model were the...