Articles by Keyword: Population Bottlenecks

Search results for Population Bottlenecks

We found 184 results for you
  1. Characterisation of microsatellite markers in the Spotted Sand Lizard (<em>Pedioplanis lineoocellata</em>) shows low levels of inbreeding and moderate genetic diversity on a small spatial scale

    Characterisation of microsatellite markers in the Spotted Sand Lizard (<em>Pedioplanis lineoocellata</em>) shows low levels of inbreeding and moderate genetic diversity on a small spatial scale

    Item type: Journal Article • Journal: African Journal of Herpetology
    Population genetic methods can be useful for understanding spatial genetic patterns, gene flow and diversity. While genetic markers such as gene sequences are useful for understanding broad scale phylogeographic patterns, microsatellite markers allow for inferences within species and on smaller...
  2. Analysis of genetic diversity in Rose’s mountain toadlet (<em>Capensibufo rosei</em>) using novel microsatellite markers

    Analysis of genetic diversity in Rose’s mountain toadlet (<em>Capensibufo rosei</em>) using novel microsatellite markers

    Item type: Journal Article • Journal: African Journal of Herpetology
    On the Cape Peninsula, Capensibufo rosei is known from only two isolated breeding populations within Table Mountain National Park. Because of its declining state, there is an urgent need to understand the genetic diversity, population structure and patterns of movement...
  3. Die effek van plantpopulasie op die saadopbrengs van sonneblomkultivars

    Die effek van plantpopulasie op die saadopbrengs van sonneblomkultivars

    Item type: Journal Article • Journal: South African Journal of Plant and Soil
    'n Aantal sonneblombasters is vergelyk by drie plantpopulasies oor twee seisoene te Ermelo, Sandvet en Warmbad. Die doel was om die kompensasievermoë van kultivars te bepaal vir 'n swak stand. Onder laepotensiaal-toestande was die kultivar X plantpopulasie-interaksie nie beduidend nie,...
  4. South African Journal of Plant and Soil Instructions to Authors

    South African Journal of Plant and Soil Instructions to Authors

    Item type: Journal Article • Journal: South African Journal of Plant and Soil
    Single maize plants (Zea mays L cv. SNK 2244) were grown in sand culture in polyethylene tubes (300 mm × 110 mm diam.) in a glasshouse. Apparent photosynthetic rate was determined at intervals during the growing period, using a portable...
  5. Die invloed van plantpopulasie op opbrengs en kwaliteit van katoen (<em>Gossypium hirsutum</em> L.) in die Vaalharts- en Sandvetbesproeiingsgebiede

    Die invloed van plantpopulasie op opbrengs en kwaliteit van katoen (<em>Gossypium hirsutum</em> L.) in die Vaalharts- en Sandvetbesproeiingsgebiede

    Item type: Journal Article • Journal: South African Journal of Plant and Soil
    Die invloed van plantdigtheid op die opbrengs en kwaliteit van katoen is vir die Vaalharts- en Sandvetbesproeiingsgebiede ondersoek. Aangesien hoër plantpopulasies hoër eise aan water- en stikstofvoorsiening stel, is hierdie effek by verskillende peile van besproeiing en stikstofbemesting uitgetoets. Individuele...
  6. Refinement and validation of the PUTU wheat crop growth model 2. Leaf area expansion

    Refinement and validation of the PUTU wheat crop growth model 2. Leaf area expansion

    Item type: Journal Article • Journal: South African Journal of Plant and Soil
    A refined leaf growth submodel was incorporated in an existing wheat crop growth model. The submodel calculated daily green leaf area expansion per plant by taking into account plant population, crop age, interplant competition, temperature and crop water status. After...
  7. The effect of plant density on the injuriousness of <em>Busseola fusca</em> (Fuller) (Lepidoptera: Noctuidae) in grain sorghum

    The effect of plant density on the injuriousness of <em>Busseola fusca</em> (Fuller) (Lepidoptera: Noctuidae) in grain sorghum

    Item type: Journal Article • Journal: South African Journal of Plant and Soil
    The influence of five different plant densities on whorl damage, internal damage, tillering and yield of grain sorghum under attack by Busseola fusca was evaluated over two seasons, using artificial infestation of three egg batches (90 eggs) per 5-m row...
  8. Maize response to plant population and soil water supply: I. Yield of grain and total above-ground biomass

    Maize response to plant population and soil water supply: I. Yield of grain and total above-ground biomass

    Item type: Journal Article • Journal: South African Journal of Plant and Soil
    The effect of the level of water deficit on the yield of grain and total above-ground biomass of maize planted at greatly differing densities was investigated in a strictly controlled field experiment, repeated for four seasons. Differences in water supply...
  9. Maize response to plant population and soil water supply II. Plant barrenness and harvest index

    Maize response to plant population and soil water supply II. Plant barrenness and harvest index

    Item type: Journal Article • Journal: South African Journal of Plant and Soil
    The effects of level of water deficit and plant population density on plant barrenness and harvest index were investigated in a strictly controlled field experiment, repeated for four seasons. Differences in soil water supply were obtained by the seasonal variation...
  10. ON THE STATUS OF CLARIAS GARIEPINUS (BURCHELL) IN LARGE MAN-MADE LAKES IN RHODESIA

    ON THE STATUS OF CLARIAS GARIEPINUS (BURCHELL) IN LARGE MAN-MADE LAKES IN RHODESIA

    Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa
    Data from some large man-made lakes in Rhodesia suggest that the populations of Clarias gariepinus have declined in these lakes. The reasons for this are not clear although commercial fishing does not appear to be responsible.