Effect of Air Temperature on Plant Reserves and Regrowth Potential in Napiergrass (Pennisteum purpurem)

The response of plant reserves to air temperature and the relationship between these reserves and the regrowth potential of napiergrass (Penniseetum purpurem) after defoliation was examined. Two cultivars, A7007 and Taishiuh No. 1, were cut in Wagner pots and established outside. The plants were moved into the growth chamber for 3 weeks of temperature treatment, from 2 weeks before to 1 week after harvest. Pour temperature combinations were examined: 15-15°C (temperature before-after the harvest), 15-35 °C, 35-15°C and 35-35°C. High temperature (35°C) before the harvest benefited plant growth but was associated with lower plant reserves. The stubble stored more reserves under low temperature. The new shoots grew vigorously when temperatures before and after harvest were high (35°C), but were less vigorous at the low temperatures ( 15° C). Overall, low temperature before the harvest and high after the harvest was the best temperature combination as it gave high levels of plant reserves and a high rate of regrowth of the new shoots.