| The randomized block design was used to study the effects of cutting time, cutting frequency and fertilization amount on the biomass of Pennisetum purpureum Rich. xP. americana King grass cv.Reyan No.4. The results showed that in some regions of Hainan from June to August (60 days), the cutting time interval in 20 days, cutting frequency for 3 times, the fresh grass biomass of the second cutting was largest and was not affected by the amount of fertilizer applied during the growth period. However, when the fertilization amount was 1 563 kg/hm2, the forage biomass was the highest, that was 41 340.10 kg/hm2; the cutting time interval was 30 days, and the cutting frequency for twice, except for the treatment of 3 127 kg/hm2. The first cutting biomass was higher than the second cutting, and the difference was significant. Under the same amount of fertilization, in terms of single cutting biomass and total biomass, the longer the cutting time interval and the lower the cutting time, the greater the biomass of the fresh grass was. The biomass of fresh grass was not significant between the cutting time was 60 days and 50 days ,but it was significantly different from other treatments. Under different fertilization conditions, when the cutting time was 40 days, that was significantly increased the fertilization amount with 4 690 kg/hm2 than that of the fertilization amount 1 563 kg/hm2. When the cutting time with interval was 50 days and 60 days, there was no difference with in yield increasing fertilizer application. |
