Abstract:
The influence of cultural practices can be modified by environmental conditions such
as container-type or positioning. The objective of the study was to determine whether
container-type and positioning would have an influence on the growth of tomato
plants and suppression of Meloidogyne javanica exposed to biomuti (Trial 1) and
Afrikelp (Trial 2). Different container-types were filled with approximately 10.4 L
growing mixture comprising steam-pasteurised sandy loam soil and Hygromix-T at
3:1 (v/v) ratio. The containers were established in microplots at 0.6 m × 0.6 m
spacing, with treatments being brown pot-below; brown pot-above, black pot-below,
black pot-above, plastic bag-above and plastic bag-below. Tomato (Solanum
lycopersicum L.) cv. 'Floradade' seedlings were each transplanted and irrigated with
500 ml chlorine-free tapwater every other day. Seven days after transplanting, each
plant was inoculated with 2000 eggs and second-stage juveniles (J2) of M. javanica.
Biomuti and Afrikelp, obtained from the Agricultural Research Council (ARC)
Vegetable, Ornamentals and Plants (VOP), were applied in separate trials weekly at
2.5%. At 56 days after inoculation, plant growth including selected nutrient elements
and nematode variables were measured. Data were subjected to analysis of
variance, with separation of means achieved using Fisher’s Least Significant
Difference test at the probability level of 5%. In the biomuti trial, container-type and
positioning had a significant effect on plant height, fruit number, dry root mass, dry
shoot mass and fruit mass, contributing 82, 48, 44, 85 and 89% in total treatment
variation (TTV) of the respective variables. Relative to brown pot-below; black pot
above, plastic bag-above and brown pot-above reduced plant variables, whereas
treatment effects were not significant on nematode variables. In the Afrikelp trial,
trends where similar to those in biomuti, treatments had highly significant effects on
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plant height, dry root mass, dry shoot mass and gall rating, contributing 91, 88, 66
and 60% in TTV of the respective variables. Relative to brown pot-below; black pot
above, plastic bag-above and brown pot-above reduced the plant variables, but had
no significant effects on nematode variables. Generally, plastic bags and
polyethylene pots below-ground improved most plant growth variables when
compared to those in containers positioned above-ground.
