DOI QR코드

DOI QR Code

The Effect of Harvesting Interval on Herbage Yield and Nutritive Value of Napier Grass and Hybrid Pennisetums

  • Manyawu, G.J. (Grasslands Research Station) ;
  • Chakoma, C. (Grasslands Research Station) ;
  • Sibanda, S. (University of Zimbabwe, Animal Science Department) ;
  • Mutisi, C. (University of Zimbabwe, Animal Science Department) ;
  • Chakoma, I.C. (Grasslands Research Station)
  • Received : 2002.04.23
  • Accepted : 2003.04.07
  • Published : 2003.07.01

Abstract

A 6 (accession)${\times}$5 (cutting interval) factorial experiment was conducted over two years to investigate the effect of stage of growth on herbage production, nutritive value and water soluble carbohydrate (WSC) content of Napier grass and Napier grass${\times}$Pearl millet hybrids (hybrid Pennisetum). The purpose of the experiment was to determine the optimum stage of growth to harvest the Pennisetums for ensilage. Two Napier accessions (SDPP 8 and SDPP 19) and four hybrid Pennisetum (SDPN 3, SDPN 29, SDPN 38 and Bana grass) were compared at five harvest intervals (viz. 2, 4, 6, 8, and 10 weeks). Basal fertilizers were similar in all treatment plots, although nitrogen (N) top-dressing fertilizer was varied proportionately, depending on the harvesting interval. The application was based on a standard rate of 60 kg N/ha every six weeks. Stage of growth had significant effects on forage yield, WSC content and nutritive value of the Pennisetums. Herbage yields increased in a progressively linear manner, with age. Nutritive value declined as the harvesting interval increased. In particular, crude protein content declined rapidly (p<0.001) from $204g\;kg^{-1}$ DM at 2 weeks to $92g\;kg^{-1}$ DM at 8 weeks of growth. In vitro dry matter digestibility decreased from 728 to $636g\;kg^{-1}$ DM, whilst acid and neutral detergent fibre contents increased from 360 and 704 to 398 and $785g\;kg^{-1}$ DM, respectively. Rapid changes in nutritive value occurred after 6 weeks of growth. The concentration of WSC increased in a quadratic manner, with peaks ($136-182g\;kg^{-1}$ DM) at about 6 weeks. However, the DM content of the forage was low ($150-200g\;DM\;kg^{-1}$) at 6 weeks. Therefore, it was concluded that Pennisetums should be harvested between 6 and 7 weeks, to increase DM content and optimize herbage production without seriously affecting nutritive value and WSC content. Accessions SDPN 29 and SDPP 19 appeared to be most suited for ensilage. It was suggested that WSC content should be incorporated as a criterion in the agronomic evaluation and screening of Pennisetum varieties.

Keywords

Napier Grass;Pennisetum Purpureum;Pennisetum Purpureum${\times}$P. Americanum;Silage;Cutting Frequency;Water Soluble Carbohydrates

References

  1. Allen, S. E. 1989. Chemical Analysis of Ecological Materials. 2nd Edition. Blackwell Scientific Publications, London, United Kingdom. pp. 164-175.
  2. Johnson, W. L., J. Guerrero and D. Pezo. 1973. Cell wall constituents and in vitro digestibility of Napier grass (Pennisetum purpureum). J. Anim. Sci. 37:1255-1261. https://doi.org/10.2527/jas1973.3751255x
  3. Jones, D. I. H., R. Jones and G. Morseley. 1990. Effect of incorporating rolled barley in autumn-cut ryegrass on effluent production, silage fermentation and cattle performance. J. Agric. Sci. (Cambridge) 115:399-408. https://doi.org/10.1017/S0021859600075857
  4. Manyawu, G. J., S. Sibanda, I. Chakoma and B. Dzowela. 1998. Screening Napier grass (Pennisetum purpureum) and interspecific hybrids between Napier grass and Pearl millet (P. americanum) for fodder production in different agro-ecological environments of Zimbabwe. Project Review on Intergrated Livestock/crop production systems in the smallholder farming systems in Zimbabwe. Proceedings of a Workshop held at the University of Zimbabwe, Dept. of Animal Science, Zimbabwe, on 13-26 January 1998. pp 81-109䡇Ⰰ਀首䡇 ソ首䡇㈀଀骖䡇㌀Ѐ˜䡇㤀฀肘䡇㼀﷿￿リ䡇䔀؀肙䡇䘀￿ル䡇䜀￿羚䡇䠀؀›䡇䤀￿羛䡇䨀܀肜䡇䬀￿￿䡇爀Ȁ€餖䥇猀ऀ䥇琀￿缘䥇甀Ā䥇瘀刺￿9䥇眀ఀ䥇砀刺￿ソ䥇騀￿首䥇鬀଀骗䥇鰀￿羛䥇鴀￿￿䥇뤀ﳿ羙ᰘ䩇먀Ѐ耛䩇묀Ȁ€䩇츀﷿リᢙ䩇케ﳿ羘馚䩇퀀ࠀ䭇Ȁ˜頚䭇ﯿ;鬜䭇
  5. Mugerwa, J. S. and B. H. Ogwang. 1976. Dry matter production and chemical composition of Elephant grass hybrids. East Afri. Agric. and Forestry Journ. 42:60-65.
  6. Tosi, H., V. P. D., Faria, L. E., Guitierrez and A. C. Silveira. 1983. Evaluation of Elephantgrass Taiwan A-148 cultivar for ensilage. (in Portuguese) Pesqui. Agropecu. Bra. 18: 295-299.
  7. Vicente-Chandler, J., S. Selva and J. Figarella, 1959. Effects of nitrogen fertilization and frequency of cutting. Agron. Journ. 51: 202. https://doi.org/10.2134/agronj1959.00021962005100040006x
  8. Butt, M. N., G. B. Donart, M. G. Southward, R. D. Pieper and N. Mohammad. 1993. Effect of defoliation on plant growth of Napier grass. Trop. Sci. 33:111-120.
  9. Muldoon, D. K. and C. J. Pearson. 1979. The Hybrid between Pennisetum americanum and P. purpureum -A review. Herb. Abstr 49 (Suppl. 5):189-199 (Abstr.).
  10. Woodard, K. R., G. M. Prine and D. T. Bates. 1991. Silages characteristics of Elephant grass as affected by harvesting frequency and genotype. Agron. Journ 83:547-551. https://doi.org/10.2134/agronj1991.00021962008300030006x
  11. Mwakha, E. 1972. Effect of cutting frequency on the productivity of Napier and Guatemala grasses in Western Kenya. East Afric. Agric. and Forestry Journ. 37:206-210.
  12. Catchpoole, V. R. and E. F. Henzell. 1971. Silage and silage-making from tropical herbage species. Herb. Abstr. 41:213-221.
  13. Wilkinson, J. M. 1983. Silages made from Tropical and Temperate crops. Part 1;The ensiling process and its influence on feed value. World Ani. Rev. 45:36-41.
  14. Gomez, K. A. and A. A. Gomez. 1984. Statistical procedures for agricultural research. (2nd edition). John Wiley and Sons Inc., Canada. p 680.
  15. Gomide, J. A., C. H. Noller, G. O. Mott, J. H. Conrad and D. L. Hill. 1969. Effect of plant age and nitrogen fertilization on the chemical composition and in vitro cellulose digestibility of tropical grasses. Agron. Journ. 61:116-120. https://doi.org/10.2134/agronj1969.00021962006100010039x
  16. Harrison, J. H., R. L. Kincaid, K. A. Loney, R. E. Riley and J. Cronrath. 1994. Fermentation and nutritive value of Zea mays and lucerne forage ensiled with added rolled barley. Grass and Forage Sci. 49:130-137 https://doi.org/10.1111/j.1365-2494.1994.tb01985.x
  17. Spitaleri, R. E., L. E. Sollenberger, C. R. Staples and S. C. Schank. 1995. Harvest management effects on silage nutritive value of seeded Pennisetum hexaploid hybrids. Postharv. Bio. and Technol. 5: 353-362. https://doi.org/10.1016/0925-5214(94)00033-O
  18. Odhiambo, J. F. 1974. The nutritive value of various growth stages of Pennisetum purpureum. East Afric. Agric. and Forestry Journ. 39:325-329.
  19. Tilley, J. M. A. and R. A. Terry. 1963. A two stage technique for the in vitro digestion of forage crops. J. Brit. Gras. Soc. 33:13-18.
  20. Woodard, K. R. and G. M. Prine. 1991. Forage yield and nutritive value of Elephantgrass as affected by harvest frequency and genotype. Agron. Journ. 83 (3):541-546. https://doi.org/10.2134/agronj1991.00021962008300030005x
  21. SAS. 1996. Statistical package of the Statistical Analytical Inc. Cary, North Carolina, USA.