International Journal of Horticulture, 2016, Vol.6, No.22, 1-14
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1.3 Weed and Pest Control
The Weed control was by both manual weeding at 3, 7 and 10 weeks after planting and chemical control which
was done three times during the period of experimentation. The herbicide used was glyphosate and applied at the
rate of 3 l/ha. Pests were controlled through application of cypermethrin (500 l/ha) and spraying commenced at
the onset of flowering and at weekly interval till the end of the experiment.
1.4 Data Collection
Data collection on growth and yield parameters commenced from the third week after planting 3(WAP) and was
terminated at the 12WAP when fruits were harvested. Data were taken on the number of leaves, vine branches,
flowers and fruits per plant; vine length per plant. Also observed were the number of cracked and rotten fruits per
plant; fruit girth and length and fruit weight per plant. The number of leaves, vine branches, flowers and fruits per
plant were determined by a visual counting of leaves, vine branches, flowers and fruits on the watermelon plant.
The vine lengh per plant was determined using a measuring tape to measure the length of the main vine from its
attachment to the root on the soil to the tip of the vine of the watermelon plant. The number of fruit rots and
cracked fruit per plant were determined by visual counting of rotten fruits and cracked fruits that were on the
watermelon plant before harvesting of fruits. Fruit length and diameter was measured using a measuring tape
around the outer part of the fruit when it has been detached from the main plant. The fruit weight was determined
as the fruit was placed on a measuring scale to give the weight of each fruit in kilogrammes. Samples of harvested
fruit from each treatment were taken to the laboratory for analysis of chemical and proximate composition. The
chemical and proximate constituents measured include N, P, K Ca and Mg, moisture content, ash, crude fibre and
ascorbic acid were determined using standard laboratory procedures and methods as described by AOAC (2002).
1.5 Data Analysis
The statistical significance of the data collected on growth and yield were subjected to analysis of variance
(ANOVA) to estimate the variance components due to manure types and watermelon varieties and their
interactions on the variables examined (Steel and Torrie, 1997). Treatment means were separated using Duncan’s
New Multiple Range Test (DMRT).
2 Results
2.1
Initial Soil Physical and Chemical Properties
The data on the initial physico-chemical properties of the soil of the site of experiment are presented in Table 1.
The particle size fraction showed that the soils are sandy clay loam in texture and low in fertility as reflected by
the low content of organic matter (3.87g kg
-1
) and total nitrogen (0.94%). The soil pH (5.52) shows that the soil is
acidic. The available phosphorus (P) with mean value of 19.60mg kg-1 was adequate. However, soil potassium (K)
content with mean value of (0.25cmol/kg) was low (FMANR, 1990).
Table 1 Physio chemical properties of soil before experimentation
Parameters
Value
Sand (%)
50
Silt (%)
27
Clay (%)
23
Textural Classification (USD)
Soil PH
5.52
Organic Carbon (%)
2.23
Organic Matter (g kg
-1
)
387
Total N (%)
0.94
