Comparisons in yields, forage characteristics, sweetness and nutritive values of Sweet grass (Pennisetum purpureum cv. Mahasarakham) and Napier Pak Chong 1 grass (Pennisetum purpureum x Pennisetum americanum) at different cutting ages

Abstract

The aim of this research was to compare yields, forage characteristics, sweetness, and nutritive values of Sweet grass and Napier Pak Chong 1 at 30, 45 and 60 days of cutting ages. The experiment was designed as a 2 x 3 factorial in completely randomized design (CRD). The treatments were performed to contain a combination of two varieties (Napier Pak Chong 1 and Sweet grass) at three stages of maturity (30, 45 and 60 days).  There were 6 treatments with 3 replications in Phetchaburi soil series. The results showed that yield of Napier Pak Chong 1 (124.86±55.86 kg Dry matter/Rai) were not significantly different compared to that of Sweet grass (158.69±56.05 kg Dry matter/Rai). Tiller height of Napier Pak Chong 1 (144.30±26.86 cm) was higher than Sweet grass (80.96±8.62 cm). However, Sweet grass had higher in tiller diameters, tiller number and leaf/stem ratio (1.90±0.36 cm, 12.66±3.34 and 6.97±4.01, respectively) than Napier Pak Chong 1 (1.39±0.13 cm, 5.33±0.99 and 4.21±3.27, respectively) (P<0.05). Napier Pak Chong 1 was not significantly different compared to Sweet grass (5.24±0.54 and 5.03±0.77 ^OBrix, respectively) in term of sweetness (P>0.05). The results showed that nutritive values (crude protein: CP) of Sweet grass (9.23±1.00%) was significantly higher than Napier Pak Chong 1 (7.03±0.45%) (P<0.05). Sweet grass at 30 and 45 days of cutting ages had the highest CP (9.83±0.31 and 9.76±0.48%, respectively). The levels of Neutral Detergent Fiber and Acid Detergent Fiber were in the ranges that suitable for using as animal feed. Therefore, Sweet grass at 30 and 45 days of cutting ages were suitable for using as a forage crops for animals due to their high CP contents.