Effects of harvesting age and spacing on plant characteristics, chemical composition and yield of desho grass (Pennisetum pedicellatum Trin.) in the highlands of Ethiopia

Bimrew Asmare,Genet Tilahun,Yeshambel Mekuriaw

doi:10.17138/tgft(5)77-84

Abstract

The study was conducted to evaluate effects of harvesting age and plant spacing on plant characteristics, composition and forage yield of desho grass ( Pennisetum pedicellatum Trin.). A factorial experiment with 3 harvesting ages (75, 105 and 135 days after planting) and 3 plant spacings (10 × 50, 30 × 50 and 50 × 50 cm) with 3 replications was used. The data collected were morphological characteristics such as leaf length, plant height, number of tillers per plant and number of leaves per plant. Chemical analysis was conducted for crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and acid detergent lignin (ADL), and dry matter yield (DMY) was quantified. Results indicated that the only morphological characteristic significantly (P<0.05) affected by plant spacing was leaf length. However, harvesting age significantly (P<0.01) affected morphological characteristics and DMY as well as CP and NDF (P<0.05). Dry matter yield increased dramatically as harvesting dates were delayed but plant spacing had no significant effect on DMY. Crude protein concentration in forage declined as harvesting dates were delayed (10.9% at 75 d vs. 9.3% at 135 d). Factors such as weed control and amount of planting material required should be the criteria used by farmers to decide inter-row spacing as, within the conditions of our study, row spacing had minimal effect on yield. As only a single harvest at each age was conducted, the yields quoted in this study are not representative of the yields provided by multiple harvests at these intervals. Further studies are needed to quantify these differences. Keywords: Biomass, harvesting day, morphological characteristics, nutritive value, plant spacing.

Highlights

Materials and MethodsLivestock production is an integral part of the subsistence crop-livestock systems in the Ethiopian highlands, as livestock provide draft power for land preparation and threshing, plus a source of cash income and assets and nutrition for the rural communities
In our study the higher plant population at narrow plant spacing was counteracted to some extent by the greater number of tillers per plant produced at wider plant spacing, individual leaves were longer at narrow plant spacing
This study has documented the increases in yield of desho grass as days to harvest are increased and has highlighted the reduction in quality, especially reduced crude protein (CP) concentrations and increased neutral detergent fiber (NDF), acid detergent fiber (ADF) and acid detergent lignin (ADL) concentrations, with advancing maturity

Summary

Introduction

Livestock production is an integral part of the subsistence crop-livestock systems in the Ethiopian highlands, as livestock provide draft power for land preparation and threshing, plus a source of cash income and assets and nutrition for the rural communities. Livestock are considered as a mobile bank that can be hired, shared, inherited and contracted by rural households (Amede et al 2005). One of the important constraints causing low productivity of livestock is low quality and insufficient supply of forage (FAO 2010). Overgrazing is common, resulting in land degradation and low carrying capacity. The decline in desirable plant species and nutritional value of the available feed resources, protein, means most animals are unable to obtain their maintenance requirements from grazing (Mengistu 1987)

Objectives

Methods

Results

Discussion

Conclusion