Dry Matter Production of Forage Plants : VIII. Influence of plant density on the dry matter production in forage plant population

Abstract

Using red clover (Trifolium pratense L.) sward, we examined the influence of plant density on dry matter production in forage plant population experimentally and theoretically. The results are as follows: 1. Though the efficiency of dry matter production on individual plant was high under low plant density condition, this efficiency on the plant population was high under high plant density condition. This tendency was indicated strongly during the early stage after cutting. The main cause for these facts was that the high density condition was superior to the low density condition in leaf area production after cutting. 2. The amount of dry matter production and CGR were calculated by eq. (8) and (9). The influence of plant density on the dry matter production was examined and analysed from the viewpoint of CO_2 balance in the plant population. From these calculations, it was clear that the high efficiency of dry matter production was shown during the early stage after cutting in the case of high density and during the late stage in the case of low density condition of the sward. These facts indicate that the efficiency of dry matter production will be heigher, if the cutting is made relatively short interval in the case of high density condition and is made relatively long interval in the case of low density condition of the sward. It is supposed from the results calculated by eq. (8) and (9) that the maximum plant density in red clover sward under the normal cultivated condition (about 60 days interval of cutting) is 400-500 plants per m^2.