Influence of lime and farm yard manure
par Dieudonne MUGOBOKA
ISAE Busogo - Bachelor's Degree 2008
The study entitled « Influence of FYM and lime on availability of Phosphorus ,growth and yield of carrot in volcanic soil of Busogo» had the aim of comparing the effect of FYM and Lime on availability of phosphorus and other related parameters such as Organic matter content ,pH (both water and KCl),Total Nitrogen, Exchangeable Magnesium and Calcium, and total exchangeable acidity ,and consequently on growth and yield of carrots in the mentioned area.
The obtained results have shown that both water and KCl pH have increased where both lime an FYM have been applied while they have slightly decreased in T0 (control) .Before experiment, both pH water and KCl varied from5.6 to 5.9 and 4.5 to 4.7 respectively. After experimentation, they respectively varied from 5.7 to 6.5 and 4.6 to 5.6.
The organic mater content was 5.603 % in control and slightly decreased up to5.52 % due to leaching by high rainfall that took place during the experimentation. In the treatments that received lime, there also was a decrease in organic matter content. Before experiment, the organic matter content was 5.654 %, 5.585 % and 5.62 %, and it became 5.52 %, 5.5 % and 5.46 %, respectively for T4, T5 and T6 after experiment .In treatments where the FYM was applied, there was an increase in organic matter content, which was 5.62 %, 5.672 % and 5.63, and became 6.2 %, 6.64 % and 6.9, respectively for T1, T2 and T3 after experiment.
The total nitrogen decreased in control and treatments that received lime and increased where the FYM was applied. Before experiment, the total nitrogen was 0.276 %, 0.270 %, 0.269 % and 0.270 % for respectively Control, T4, T5 and T6. At the end of experiment, the total nitrogen content was respectively 0.276 %, 0.270 %, 0.269 % and 0.270 %. For the treatment that received organic matter, there was an increase in total nitrogen; the total nitrogen content was 0.279 %, 0.2836 % and 0.280 and it became 0.29 %, 0.320 % and 0.339 % after experiment, respectively for T1, T2 T3.
The Ca content in soil slightly decreased in control and increased in other treatments. Before experiment, it varied from 0.62 meq/100g to 64 meq/100. After experiment, it varied from 0.6 meq/ 100g to 0.75 meq/ 100g.
The Mg showed the little change in all treatments. It decreased in Control and increased in all other treatments. It varied from 0.26 meq/100g to 0.28 meq/100g and 0.24 meq/100g to 0.296 meq/100g, respectively before and after experiment.
The phosphorus increased in all treatments except Control where there was a decrease. It varied from 60 ppm to 60.5 ppm and 59.5 ppm to 70 ppm, respectively before and after experiment. According to obtained results, both lime and manure improved soil properties.
For the height of plant, it varies from 8.3 cm to 11.2 cm, 20 cm to 29 cm and 41.8 cm to 45 cm respectively at 30 days, 60 days and 90 days. The length of tap root at harvesting time varied from 11.5 cm and 17.1 cm and the diameter varied from 2.7 cm to 3.9 cm. The yield of tap root varied from 12.1t/ha and 22.5 t/ha. For all agronomic parameters, the FYM showed the best performance, followed by lime and the Control showed the last performance.
From the results obtained above, the following recommendations are formulated:
Ø The use of organic matter is of paramount important in volcanic soil of Busogo as it plays a major role in improving soil properties and supplying nutrients to grown crops. Chemical fertilizers must be used in combination with organic matter to supply others plants nutrients because even if Phosphorus may be sufficient, in the absence of others elements, their effect is not remarkable for increasing the yield.
Ø As the volcanic area is subjected to high rainfall all over the year, the soil is susceptible to become more acidic by leaching of basic cations (Rayar, 2000). The liming is necessary after soil pH analysis because the soil pH below 5.5 is not suitable to many crops as it causes the Aluminum toxicity to crops (Arthaud, 1982).
Ø In case of liming, both calcite and dolomite limes are recommended as the level of both Magnesium and Calcium is very low.
Ø The study should be repeated in different seasons and at different sites in volcanic soils, using different sources of both organic and mineral amendments, to verify the obtained results. The study of effect of the combination of different sources of both organic and mineral amendments should be carried out to compare their influence on the phosphorus availability.