Growth And Yield Of Fluted Pumpkin

Introduction:

Vegetables are considered as minor crops and as such are planted in small patches or as individual stands or at the fringes of the farms (Chiweya and Eyzaguirre, 1999). Different tillage methods are used in different regions of humid tropical Africa for fluted pumpkin (Telfaria occidetalis Hook. F). Depending on soil type, rainfall and cropping patterns, farmers in Africa plant fluted pumpkin on flat, ridges or mounds. However, productivity improvement in fluted pumpkin is constrained by a number of biotic and abiotic stresses. This is a way to improve in the productivity; appropriate methods and indigenous soil management practices should be studied.

Although, planting on flats is the best method for weed suppression, its tillage requirement is inconclusive. Therefore this work was conducted to ascertain its productivity performance in relation to tillage practices in the Southwest Nigeria. These tillage methods degrade soil quality; reduce chemical and biological qualities especially in case of altisoils located in the rainforest areas of Southwest Nigeria (Awodun, 2006).

Materials and Methods:

Field Experiments:

Experiments were conducted at two sites (Oda and Aponmu) in Akure (Latitude 70 30’ and Longitude 30 52’E) in 2002 and 2003. The surface soils which overlie metamorphic rock of the basement complex is classified as Oxic Tropuldalf (Luvisol) (Akintunde et al., 2000). Four tillage treatments replicated three times were applied to groundnut in a randomized complete block design. The treatments were:

• Manual clearing (i. e initial clearing with cutlass eight days to planting).

• Manual heaping (with hoe).

• Manual ridging (with hoe).

• Manual bed-making (with hoe and rake).

Each plot was 9m2 and seeds bought from the Horticultural unit of Ondo State Agricultural Development Project (ODSADEP), Ondo State, Nigeria, were extracted by cutting open the pods with a sharp cutlass. The extracted seeds were packed into polythene bags

containing sawdust and shade dry for 5 days to induce germination and reduce dormancy period. It was then planted on the field at a spacing of 1m x 0.8m.

Initial soil analysis:

Surface (0-15cm) soil samples were collected from Oda and Aponmu sites and bulked for routine analysis. The soil samples were air-dried and sieved (2mm). Mechanical analysis was done using the Bonyoucous hydrometer method, soil organic matter was determined by wet digestion method, total N was determined by the micro-kjeldahl method, available P was extracted with Bray-1-solution and determined by molybdenum blue colorimetry; exchangeable k, Ca and Mg were extracted with ammonium acetate, k was determined using flame photometer and Ca, Mg by EDTA titration (Carter, 1993).

Growth and Yield Data:

Ten plants were selected per plot for determination of growth (Days of emergence; number of leaves; length of vine; plant height; number of branches; length of nityriods and stem girth) and yield (whole plant weight, leaves weight, vine weight and root weight) parameters. All these yield data collected for the two cations were similar, so it was linked to get the final yield data

Statistical Analysis:

Plant data were subjected to analysis of variance and least significant difference at 95% level of probability was used to compare data on treatment basis.

Results and Discussion:

Surface soil layers (0-5, 5-10, 10-15cm) at the sites were sandy clay loam with sand between 59-60%, silt 24-25% and clay 4-15%. Organic matter varied between 1.34- 2.24, total N 0.08-0.14%, available P 0.7-2.6 mg/kg, exchangeable k 0.03-0.46 cmol/kg, exchangeable Mg 0.40-1.10 cmol/kg. The soils were marginal in organic matter, deficient in N, P, k and Ca and adequate in Mg (Akinrinde and Obigbesan, 2000).

Table 2 presents data on number of leaves as influenced by tillage methods adopted in both sites of the experiments. At 2 weeks after planting, there were significant differences regarding stem girth between bed and other tillage methods but there seems to be no different in flat, heap and ridge compared. Considering other weeks (4, 6, and 8 weeks) of data observation, it shows that the same trends persist, that is ridge, gave highest number of leaves of Telfaria. Also, Table 3 has data on the effect of tillage on the length of vine of Telfaria occidentalis. There were significant differences between plants grown in the ridge and those grown on each of the other tillage systems (Bed, flat and Heap).

Tables 4 and 5 present data on number of branches and length of materials as influenced by the different tillage methods used. At 2 and 4 weeks after planting there were significant difference between heap and ridge treatments. Equally, at 4 and 6 weeks after planting there were significant difference in the length of materials between bed and flat system of tillage treatments. At harvest approximately twelve weeks after planting (12 WAP) in figure 1. Compared with ridging treatments, bed, flat and heap gave lower values of telfaria yield. The overall marketable yield (Plant weight) per plant were 327.0, 290.1, 307.1 and 547.7g for bed, flat heap and ridge treatment respectively. Also in figure 1, the consumable yield (average leaves weight) increased in the order of flat, heap, bed and ridge. The overall mean values of leaves weight were 172.0, 177.0, 190.0 and 434.5 respectively. Figure 1 still shows the vine length and root weight respectively. There were significant differences in the weight of vines planted on beds, flat and heap but compared with ridge, significant differences exist (P=0.05). Average root weight was 27.5, 28.0, 29.5 and 31.9g per plant for heap, ridge, bed and flat tillage treatment respectively.

The overall pictures of all the parameters observed clearly showed that ridge gave higher values and tended to be the best of all the tillage treatments compared this might be attributed to the fact that, ridging reduce soil density, increased soil macro porosity thereby reducing conduct of heat into the soil during the day (Awodun, 2006). Although, in the other tilled plots (heap and bed) considerable good performances were observed on the total parameters observed this is because, there is better uptake of nutrient especially phosphorus which result due to mineralization or organic matter when mixed with soil during tillage (Taylor et al 1986 cited by Awodun and Ojeniyi, 2002). However loosening of soil enables root elongation and better uptake of nutrient below the surface due to downward movement of the absorbing roots.

Conclusion:

Ignorantly, fluted pumpkin is traditionally grown on the flat, bed, heaps and ridges unminding the yield gotten therefrom. This study has been able to show that the most suitable soil tillage practice for the profitable production of fluted pumpkin (T. occidentalis) is the ridge. This is evident from number of leaves, length of vines, plant height, number of branches as well as the total yield of plants planted in ridges compared with plants on other soil tillage practices.

Author:

M. A. AWODUN
Department of crop, soil and pest management, Federal University of Technology,