刈割和施肥对热研4 号王草生物量影响初报

采用随机区组设计研究刈割时间、刈割次数和施肥量对热研4号王草生物量的影响,结果表明,热研4号王草在海南夏季6～8月份60 d的生长期内,刈割时间间隔20 d、刈割3次的处理,第2次刈割的鲜草生物量最大,且不受施肥量的影响。但当施肥量为1 563 kg/hm~2时的牧草生物量最大,为41 340.10 kg/hm~2;刈割时间间隔30 d、刈割2次的处理,除施肥量为3 127 kg/hm~2的处理外,第1次刈割均比第2次刈割产量高,且差异显著。在相同施肥量下,就单次刈割生物量和总生物量而言,刈割时间间隔越长、刈割次数越低,鲜草生物量就越大,刈割时间为50 d和60 d之间鲜草生物量差异不显著,而与其他处理差异显著,不同的施肥条件下,在刈割时间间隔40 d时,施肥量为4 690 kg/hm~2比施肥量为1 563 kg/hm~2的产量显著增加。在刈割时间间隔50 d和60 d时,随着施肥量的增加,产量并无差异。

Effects of cutting and fertilization on biomass of Pennisetum purpureum Rich. xP. americana King grasscv. Reyan No. 4

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.