Mass propagation of bamboo and its adaptability to waste water gardens

Author: Murage, Hunja

Awarding University: Jomo Kenyatta University of Agriculture and Technology, Kenya

Level : PhD

Year: 2009

Holding Libraries: Jomo Kenyatta University of Agriculture and Technology Library ;

Subject Terms: Bamboo ; Plant reproduction ; Water treatment ;

Pages: 246

Advisors: Catherine Muthuri/Colin Black

Abstract:

Mass Propagation of Bamboo, and its Adaptability to Waste Water Gardens Unregulated and inappropriate disposal of wastewater poses serious pollution problems in many parts ofthe developing World. However, reuse of wastewater may help to ameliorate global water shortages, especially in developing nations where facilities for safe disposal of wastewater do not exist. Some bamboo species grow more rapidly than timber species and have numerous actual and potential applications for environmental conservation and income generation. In view of these attributes, bamboo was chosen for use in the present study of the potential utilisation of wastewater to improve water and nutrient supplies, while providing an environmentally compatible method for wastewater disposal and a fast-growing, non-timber source of woody material for subsistence farmers As the extremely long vegetative period before flowering occurs in many species limits seed supplies, it is vital to develop effective methods for mass propagation of bamboo to enable its widespread adoption by subsistence farmers in East Africa. Seven potentially important species were used in studies intended to develop suitable micropropagation procedures: these were Dendrocalamus membranaceus, Dendrocalamus yunnanicus, Dendrocalamus strictus, Phyllostachys heterociada, Oxytenanthera abyssinica, Phyllostachys pubescene and Dendrocalamus giganteus. Multiplication rates differed between species (P<O.OOI) and these difference became apparent within five months of establishing the cultures. D. yunnanicus was the most promising in terms of multiplication rate, easily outperforming all other species (P<O.OO 1), by increasing to 3,500 plantlets within eight months. species (Dendrocalamus giganteus, Bambusa vulgaris and B. nutans) were grown in 100 tanks in a factorial experiment under field conditions. Sewage effluent or clean water was applied daily according to the treatment involved. A second experiment contained 339 younger plants irrigated with three sources of water, including industrial wastewater. Subsequent analysis revealed that the wastewater did not contain toxic concentrations of nutrients or trace metals. Weekly and diurnal measurements of net photosynthesis, transpiration rate and stomatal conductance were made over a nine month period, while non-destructive measurements of plant height, collar diameter, number of leaves and leaf area were made over a 15 month period. Destructive harvests after 0, 9 and 15 months of treatment were used to determine leaf and stem fresh and dry weights. When averaged over all species, irrigation with wastewater increased stem fresh and dry weight plant' by 30-40 % relative to plants receiving clean water (P<0.05), with B. vulgaris and B. nutans performing better than D. giganteus. A significant water*time interaction was apparent for plant height, branch number, leaf area plant' and biomass production for all species; values were greater for plants irrigated with wastewater than in those receiving clean water. Volumetric soil moisture content did not differ significantly between the clean and wastewater treatments between March and November 2006, but differed between the two measurement depths (20 and 60 em; P<O.OO 1). The gas exchange and SPAD values (an indirect measure of chlorophyll concentration) revealed several significant effects. SP AD values varied with time (P<O.OO 1), but not between species, and were greater in plants irrigated with wastewater than in those receiving clean water (P<O.OO 1). Stomatal conductance, transpiration and net photosynthesis all showed significant effects of species, irrigation treatment, time and leaf position in the canopy (P<0.05). Instantaneous transpiration efficiency (ITE) was greater in plants irrigated with wastewater than in those receiving clean water (P<0.05). Elemental analysis showed that the concentrations of trace metal nutrients in the wastewater supplies used in both experiments were not sufficiently