Influence of lime and farm yard manure

4.1.4. Available phosphorus

The available phosphorus in soil varies from 60ppm to 60.5ppm and 59.8ppm to 75.815ppm, respectively before and after experiment.

This range classifies the soil into «high content» range (MUTWEWINGABO et RUTUNGA, 1987), (Van Der Zaag, 1981).

The variation of available phosphorus before and after experiment according to treatments is shown on the figure below:

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Figure : Available phosphorus before and after experiment.

It is observed from the figure above that there is a decrease in available phosphorus content for T₀ .This may be caused by crop uptake, leaching by rainfall water and phosphorus retention by acidic cations as both p H and Total exchangeable acidity has increased.

For other treatments, there has been an increase in available phosphorus content. The ANOVA table below shows whether the difference observed among treatments is significant.

Table : ANOVA table for available phosphorus after experiment.

Source of variation	DF	SS	MS	F.Observed	F.Table
Total	27	7752	287.142	-	-
Block.	3	26	8.666	0.048	5.09
Treatment.	6	4442.85	740.47	4.05	4.01
Error	18	3284.0	182.44	-	-

CV %= 15.1

From the above table, it is clear that a high significant difference at threshold of 1% occurs between treatments as F. observed is greater than F. table at 1% threshold. The difference observed between blocks is not significant as the F ratio is lower than the value of F .table at the same threshold.

Tableau : Mean separation for available phosphorus observed after trial

Treatments	Mean in ppm	Homogeneous group
T3 T2 T6 T5 T1 T4 T0	75.5 71 70 66.5 65.5 62.5 59.5	A B B C C CD D

Considering the mean separation of available phosphorus, it is remarkable that all treatments are classified into five groups (A, B, C, CD, and D).

In the treatments that have received FYM, increase in available phosphorus is due to liberation of phosphorus in the decomposition phase of organic matter (Russell, 1980).In this phase, the organic acids formed also dissolve the unavailable phosphorus and become available phosphorus (Rayar, 2000).

For the treatments that have received lime, the increase in available phosphorus is due to neutralization of power of active acidic cations by lime as it has been discussed in chapter 2.

4.2 PLANT GROWTH

4.2.1 Height of plants at 30 days

The results obtained on plant heights after 30 days in different plots as per 7 treatments are presented on appendix 2 while the mean heights are presented on the following figure:

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Figure : Heights of plants after 30 days in the study zone

It was observed that the mean heights vary from 8.3cm to 18cm with the general mean of 11.8cm.The T₂ and T₃ showed the highest values while T₀ shows the lowest value.

Though the difference between treatments has been revealed, ANOVA test is to be conducted to know whether the difference observed between treatments is significant.

Table : ANOVA Test for heights of plants at 30 days

Source of Variation	DF	S.S	M.S	F.Ratio	F.Table at 1%
Total Block Treatments Error	27 3 6 18	343.361 9.161 317.898 16.301	12.717 3.053 52.983 0.9056	3.37 58.503	5.09 4.01

C.V %=8.04

From the table above, there is a significant difference between treatments at 1%threshold as the value of F Ratio is greater than the value of F on the table at the mentioned threshold. The difference observed between blocks is not significant as the F ratio is lower than the value of F .table at the same threshold.

Table : Mean separation of plant s heights after 30 days of sowing

Treatments	Mean height in cm	Homogeneous groups
T3 T2 T6 T5 T1 T4 T0	18 15,7 11,2 10,6 9,5 9,5 8,3	A B C CD DE DE E

The table mentioned above shows that the treatments are classified into 6 groups (A, B, C, CD, and DE, E).The group A shows the best results T₃.The group B represents the mean heights of T₂, while the group C shows the mean heights of shows the mean heights of T6.The treatments T₅, T₁, T₄, and T₀ are almost the same.

The best results for T₃, followed by T₂ are due, according to Miller and Donahue (1990), the supply of the plant nutrients, especially Nitrogen which is the limiting factor for plant growth.