Complementary dominance of themeda triandra and panicum maximum examined through shoot production

Abstract

Sustained regrowth after defoliation was typical of P. maximum plants grown in the shade, whereas T. triandra plants were weakened under these conditions. Of three provenances of T. triandra tested, the Lowveld form was less tolerant of shading than either the Bushveld or Sourveld form. All of the grass plants responded to shading by showing an increase of leaf area. High moisture levels consistently recorded in leaves of P. maximum were thought to enhance its palatability and thereby promote its selective removal by grazing in open areas where T. triandra thus becomes dominant.

Uittreksel

‘n Groot vermoë tot aanhoudende hergroei stel. P. maximum in staat om met welslae in skaduwee te groei terwyl T. triandra minder in staat is om ontblaring in die koelte te duld. Drie variëteite van T. triandra is ondersoek en dit is gevind dat die Suurveld vorm minder skaduwerend is as Bosveld of Doringveld vorms.

Beide soorte het skaduweetoestande teengewerk deur die ontwikkeling van groter blaar oppervlakke. Dit word as waarsknylik geag dat die hoër vog‐inhoud wat gereeld in die blare van P. maximum aangetref is dat so ‘n mate die smaaklikheid van hierdie grässoort bevorder het dat dit selektief afgewei is op oop gebiede, met die gevolg dat T. triandra derhalwe daar die dominante soort word.