The use of light‐proof boxes for the measurement of plant vigour in cocksfoot (dactylis glomerata l) and lucerne (medicago sativa l).

Abstract

The light‐proof box method was used to measure the potential vigour of cocksfoot and lucerne plants which had previously been subjected to different cutting frequencies. The yields of etiolated regrowth in cocksfoot plants that were well supplied with soil moisture declined with each successive harvest. In the lucerne trial the soil moisture content varied over a wide range and the etiolated regrowth yields correlated well with soil moisture content. The amount of etiolated regrowth made during the first twenty days in both species was olosely correlated with the total amount for the different treatments and therefore it was unnecessary to continue harvesting plants until growth ceased. Weight per growing organ was shown to be the most sensitive measure of plant vigour.

UITTREKSEL

Die potensiële groeikrag van kropaargras en lusern, wat eers aan verskillende snyfrekwensies onderwerp was, is met behulp van die ligdighouermetode bepaal. Die hoeveelheid geëtioleerde hergroei van kropaargras, onder gunstige grondvogtoestande, het met elke snysel verminder. In die lusernproef waar ‘n wye reeks grondvogtoestaride geheers het, is die opbrengs van geëtioleerde hergroei goed met grondvog gekorreleer. Geëtioleerde hergroei van albei gewasse gedurende die eerste 20 dae is sterk gekorreleer met die totale geetioleerde hergroei van die verskillende behandelings. Dit is dus nie nodig om aan te hou met sny totdat die plante opgehou het met groei nie. Gewig per groei‐orgaan blyk die mees sensitiewe maatstaf van groeikrag te wees.

Notes

Present address: Döhne Research Institute, Stutterheim, Cape Province.