Competition for Light between Annual Species of Trifolium during the Vegetative Phase

摘要: The goal of the investigation was evaluation relationship leaf area and position to dry matter production by species components mixed (two species) communities in contrast their simple (single communities. selected for study were closely related winter-annual legumes, Trifoliur subterraneum L. (subterranean clover), T. hirtum All. (rose incarnatum (crimson clover). These three clovers are quite compatible under field conditions when sown together pasture (Williams, Love, Berry 1957). Their relative amounts fluctuated widely, however, during successive years natural regeneration. Since factors underlying these fluctuations must be considerable ecological import, a series investigations initiated influence mineral nutrition, temperature, moisture, light, other on competitive ability species. Species interactions determined relation while all kept as favorable constant possible among within Black (1957) Donald (1961), recent reviews work competition light crops communities, emphasized importance solar radiation determining productivity. Light is major vegetative productivity herbaceous which considered heliotropes, i.e. plants requiring high intensity rapid growth (Black A large significant part winter annual's life cycle, extends through periods short days proportion cloud cover. experiment therefore conducted circumstances Mediterranean-type climate Adelaide, South Australia. experimental site because its similarity low elevation, intermediate rainfall range areas Californiia.