Green panic (Panicum maximum Jacq. var. trichoglume Eyles) is one of the popular forage grasses cultivated in southern Kyushu, Japan. However, the forage productivity in autumn and overwintering ability of green panic in that area were low, due to its sensitivity to frost
and low temperature. For confirming the possibility of improving the tolerance to these stress conditions in green panic by gibberellin (GA3) and compound fertilizer application, GA3 treatment with 200 ppm solution at the rate of 80 ml/m2 and additional fertilization treatment at the rate of 10g/m2 each of N, P2O5 and K2O were applied to the field-grown plants on
October 27, 1992. Dry matter productivity of plants in late autumn was increased by both treatments, owing to the increase in net assimilation rate and plant leaf area. And the overwintering ability was improved through enhancing leaves to be tolerant to the low temperature and to be insensitive to lethality before winter, and through protecting tiller death during winter by both treatments. The results suggested that both GA3 spray and additional fertilization may be used as a promising cultivation means to improve herbage productivity
in late autumn and overwintering ability of green panic sward in southern Kyushu, Japan.