Abstract
Napier grass (Pennisetum purpureum Schumach), the most preferred fodder species for dairy production in East and Central Africa, is under threat from stunt disease caused by Candidatus Phytoplasma oryzae (Ns-phytoplasma). The disease reduces forage yield by 40 to 90%. Two alternative fodder grasses, Guinea grass (Panicum maximum Jacq) and Guatemala grass (Tripsacum laxum Scrib and Merr) and a new stunt disease tolerant Napier cv Ouma 3 were studied to determine their biomass production potential when subjected to three intervals harvest (4, 8, 12 weeks) alongside three basal heights of defoliations (5, 10 and 15 cm). The study was conducted at KARI, Kakamega (high rainfall zone) and KARI, Alupe (low rainfall zone) in Kenya. A split-split plot design with 3×3×3 factorial treatment arrangements was used. A 4-weekly interval of harvesting alongside defoliation heights of 10 and 15 cm significantly increased biomass yield in Napier cv Ouma (38.47 and 33.90 T/ha/year respectively) compared to Guatemala grass and Panicum maximum which yielded 23.3 and 27.4 T/ha/year respectively. There is appositive correlation between yield and morphological parameters with canopy diameter, plant height and number of leaves highly correlating in biomass yield. Key words: Frequency of harvest, alternative species, defoliation height, biomass yield, fodder species.
Highlights
In Sub-Saharan Africa improved grasses and legumes have been recommended for livestock production due to their high dry matter yield as well as nutritive value (Onyeonagu and Asiegbu, 2013)
Muyekho et al (2003), where dry matter yield of recommended Napier grass varieties (Bana grass, French Cameroon and Clone out-yielded Guatemala grass when harvested at 4-weekly interval along with defoliation height of 10 cm above the ground This could be explained by cumulative biomass yield after several repeated harvests (12 times) for the 4-weekly intervals compared to 8-weeklyinterval which was repeatedly harvested 6 times and 12-weekly intervals which had three repeated harvests within the experimental period of two years
The trend of increased dry matter yield with interval of harvest in this study is in agreement with the findings of Saddul et al (2004) who obtained increased biomass yield with increased intervals of harvest
Summary
In Sub-Saharan Africa improved grasses and legumes have been recommended for livestock production due to their high dry matter yield as well as nutritive value (Onyeonagu and Asiegbu, 2013). Napier grass (Pennisetum purpureum Schumach) is the most preferred fodder species for dairy production in East and Central Africa It can provide a continual supply of green forage throughout the year and it fits in intensive small-scale farming. It is the dominant grass in zero-grazing systems and can out-yield many other grasses such as Guinea grass (Panicum maximum) and Rhodes grass (Chloris gayana) (Orodho, 2006). It can withstand repeated cutting, and four to six cuts is able to yield 50 to 150 tons per hectare per year (Orodho, 2006).
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
