A Dissertation Submitted in Partial Fulfilment of the Requirements for the Degree of Master's in Life Sciences at The Nelson Mandela African Institution of Science and Technology
Chromolaena odorata is a weed that has infested agricultural land in the Serengeti district and
adversely reduced cropland and crop yield. This study evaluated the impact of climate change
and the management cost of Chromolaena odorata on maize production in the Serengeti
District. Firstly, the available roads were used as line transects for Chromolaena odorata
observation. Global Position System coordinate collected was used to generate a distribution
map of Chromolaena odorata in the Serengeti district. Climate change impact on maize
production was assessed using maize production data from 2000-2018 from the Serengeti
District office. Climate data were from the Grummet Game reserve. Correlation analysis was
used and the results showed rainfall and maize production were positively correlated, (r = 0.08
and p = 0.73). Mean annual temperatures and maize yield were positively correlated, however,
the correlation was not significant (r = 0.47 and p = 0.12). Therefore, the climate in Serengeti
was not only the factor for the decline in maize yield. A field trial was performed in Serengeti
to investigate the management cost and frequency of weeding on the growth and yield of maize,
and to determine the best frequency of weeding to get an optimum yield. There were five
treatments replicated four times. Treatments were; No weeding, weeding once, twice, thrice,
and fourth. The highest yield was obtained in weeding four times treatment with 2403 kg/ha
with significantly different (P<0.05, P=0.014). The lowest yield was obtained in no weeding
treatment with 520 kg/ha. There was an addition of 1883 Kg. ha-1
of maize grain yield
equivalent to a 70% increase Marginal return rate in weeding four times treatment. This study
suggests that for better maize yield and profit farmers should perform weeding four times to
control Chromolaena odorata on their cropland.