| dc.description.abstract | The study of the quality of water used in the spray tanks is important because it can affect
herbicide efficacy. Thus, this study was aimed at contributing to effective weed control in
farmers’ fields through elucidating on the possible positive and negative interactions of
glyphosate herbicides with water sourced from the varied available reservoirs. The five water
samples were collected and analyzed in the laboratory using different types of standard analytical
techniques. The parameters analyzed include; pH, total alkalinity (CO3
2- or HCO3
-), calcium
hardness, Magnesium hardness, total hardness, Na+, K+ and total suspended solids (turbidity).
The field experiment was laid out in a randomized complete block design with six treatments and
three replications. There were three villages (Kisaalizi, Kimole and Podya), in which three field
plots with weed species (predominantly Sodom apple (Solanum incanum), Spear grass (Imperata
cylindrica) and Couch grass (Digitaria scalarum), that were broadly differing from one field to
another were randomly selected. Data was collected on different water quality parameters in the
laboratory and scorching effect and analyzed using GenStat software program. Results on water
quality parameters indicated that bore hole 2 (near Lake Kyoga) had the highest pH (7.15), Mg2+
(19.899 ppm), Ca2+ (367 ppm), Na+ (412 mgl-1) and total alkalinity (547.5 ppm); yet dam water
had the highest K+ (75 mgl-1) and rain water had the lowest K+ (6 mgl-1). The scorching effect
was significant (P < 0.001) between the different water sources. The scorching effect of
glyphosate herbicide was highest with control (4.33) and lowest with borehole 2 (2.22). The
mean scorching effect of glyphosate herbicide was also highest in Podya village (3.72) followed
by Kimole village (3.44) and Kisaalizi village (3.33) with the least. In conclusion, in the context
of effect of water source on efficacy of glyphosate herbicide in weed control in Lwampanga subcounty,
Nakasongola District farmers should not use Borehole water (B2) to mix with glyphosate
to form spray solution. However, if optimum scorching effect is to be obtained in farmers’ fields,
they should use Rain water, Lake Water, Dam water and Borehole water (B1). It was
recommended that farmers in order to realize the full benefits of glyphosate in weed control, it is
essential that adjuvants are added to the solution before use, to enhance its effectiveness in
farmers’ fields. It was suggested that more research should be done to assess the synergistic or
antagonistic interactions of glyphosate anion and water cations. | en_US |
