Some
of the most wide spread and troublesome weeds in cucurbit crops in the southern
region includes ; pigweeds(amaranthus
spp) especially palmer amaranth (A.palmeri) yellow and purple nut sedges (cyperus esclentus and C.rutundus)
and morning glories (ipomea spp) (Weaber,2002;Webser,2006). Bermuder grass(cynodon dactylon)crab grass(digitaria spp), horsoettle(solarium carolinese),common pink
purslanes (portolaca oleracea and p.
pilosa) florida pusley(richardia scabra and sicklepod)(cassia obtusitoha ) have been sited as wide spread or troublesome
in several southern state.
Field trials in fiorider showed that just
one or two pigweed plant per squre yard growing with cucumber throughout
cropping cycle can reduce yields by 10% while 5-7 weed per square yard can cut
yield by half or more (Berry et al,2006)
Plant Spacing
Pant spacing is the way plants are arrange
on a row in a farm there are countless ways of spacing plants. observation of
the morphological characteristics of the plants together with experience will
help the gardener to choose the arrangement best suited to local conditions.
Advantages of
Spacing to Vegetable Crops Includes
1.
Right
spacing result in an efficient use of space and reduce competition between
plants with the same cultural requirements.
2.
The
distance between plants will also affect microclimate particularly with
reference to wind and moisture.(Nguyen,1989).
3.
Plant
spacing increases the benefit between different plants. The benefit can take
many forms such as enriching the
nitrogen content of the soil , repelling
pest or giving shade.
Dena harris item number: article21, have it
that trellised cucumber should be planted 2-3 feet apart on a trellised,
approximately 6 feet high. For ground varieties plants at least 18 inches apart
60-91cm and 45cm.
In
an experiment to test the effect of pruning and two plant spacing 75× 30cm and 75× 40cm on tomato, zero pruning at the
closer spacing (75 ×30cm) had a significantly higher yield than the wider plant
spacing (75×40cm) (Evan,1982). Tomato variety seed was grown in five different
spacing -30cm ×100cm, 40cm ×100cm, 50cm ×100cm,50cm ×100cm and 75cm ×100cm. the
result showed that the closest plant spacing (30cm 100cm) gave the highest
total yield (21.3t/ha) and marketable yield (17.5t/ha) while the widest spacing
(75cm×100cm) gave the lowest total and
marketable yield of 12.4t/ha and 9.3t/ha respectively (Monjur,1984).
Shuangxi(1984)reported that the yield of
marketable fruits from Tainan,no2 tomato plant grown in the closest spacing of
100cm×30cm was significantly higher than those grown in wider spacing. An
increase in marketable fruit yield of 15.22t/ha was produced as the area per
plant decreased from 1.7 to 0.30 square
meter.
In a trial with tomato planted at different
seedling ages of 15, 20, 25 and30 days
and plant spacing of 50cm ×100cm,40cm ×100cm, 30cm ×100cm and 20cm
×100cm, Asoka(1986) reported that the 25day old seedling planted at a spacing
of 20cm ×100cm produced the highest yield.
Nguyen(1989) found that with six different
spacing (60cm ×100cm, 40cm× 100cm, 25cm ×100cm,60cm× 75cm, 40cm ×75cmand 25cm
×75cm)on the tomato cultivars- p502,plant spacing of 25cm×75cm gave the highest
total and marketable yields.
Uddin
(1996) reported that two stem pruning and the closest plant spacing
(40cm×100cm) gave the highest yield of 56.2t/ha.
Yanrong(1998)
evaluate the effect of pruning and two spacing treatments-80cm× 50cm and 80cm×
40cm on tomato. He observe that plant spaced at 80cm ×40cm had higher yield of
41.8t/ha than those spaced at 80cm ×50cm whose yield was 36.7t/ha.
Indeterminate tomato variety was grown in one
plant per hill and two plants per hill with four different spacing via-85cm
×25cm,85cm ×30cm, 85cm ×40cmand 85cm ×50cm. Ali(1995) reported that there were
no significant difference on the marketable and total yield among the spacing
and that the widest spacing -85cm ×50cm with one plant per hill was found to be
better overall other treatments.