The aim of this study is to determine how plant growth is affected by Rhizobia bacteria and fertilizer. The histogram in figure 1 indicates that the change in biomass of pea plant species was higher under Rhizobia + fertilizer. Pea plant species comes from a legume family. According to Taiz and Zeiger (2010), these plant species enter into a symbiotic relationship with root-nodule bacteria, referred to as Rhizobia. Based on the results, the increase in biomass under rhizobia+ fertilizer is strongly influenced by the symbiotic relationship of pea with nitrogen fixing bacteria (Franche et al., 2009). Change in biomass under Rhizobia only was also high but not higher than Rhizobia+ fertilizer, this is because the addition of fertilizer in Rhizobia +fertilizer had speed up …show more content…
Maize plant species are not legumes, they respond in a low rate to Rhizobia compared to the rate at which pea plants (legume plants) respond (Somasegaran and Hoben, 2012). Rhizobia have more beneficiary effect on growth of legumes (Somasegaran and Hoben, 2012). According to the observations made during the experiment, roots in treatments with fertilizer (i.e. fertilizer only and Rhizobia +fertilizer) were brown in colour. According to Silva and Uchida (2000), fertilizer reduces nitrates in soil causing a brown colour in roots. Roots had the highest increase in biomass under untreated, this is because when soil nutrients are high a plant spend much energy in building roots to forage in the soil for new nutrient sources (Vallentine, 1980). According to (Vallentine, 1980), roots biomass is highest where soil quality is poorest. Shoots had the highest increase in biomass under fertilizer +Rhizobia and lowest increase under Rhizobia only. The increase in biomass of the number of leaves was higher under Rhizobia and fertilizer compared to other