Thesis (M. Agricultural Management (Plant Production)) -- University of Limpopo, 2020 / Tomato is a major vegetable crop produced in Limpopo province by subsistence and
commercial farmers. Biotic and abiotic factors such as diseases and drought affect its
productivity and yield negatively. The most economically important tomato disease in
Limpopo is early blight, caused by Alternaria solani. Early blight affects tomato
growing under stressful conditions such as drought. The main aim of this study was to
evaluate water management in tomato production and its effect on tomato yield, early
blight occurrence and severity under smallholder farming systems in Giyani. A survey
study and field experiments on early blight occurrence and severity were conducted in
the Greater Giyani municipality in Limpopo province. Firstly, a survey of early blight
was conducted in tomato fields selected from three service centres namely Guwela,
Hlaneki and Mhlava Willem. Twenty five potential tomato grower’s farms were
randomly selected for survey based on the location and production management
strategies. A second study was carried out by establishing field experiments at two
farms in the same area, namely: A hi tirheni Mqekwa and Duvadzi farms. The
experiments were laid out in a randomized complete block design (RCBD) in a split
plot arrangement, with irrigation as the main plot treatment and tomato variety as the
subplot treatment. Each treatment was replicated four times. The irrigation treatments
consisted of full irrigation up to field capacity and deficit irrigation. The tomato varieties
planted were HTX14, Rodade, STAR9006 and Commander, and were irrigated with a
drip irrigation system. The overall survey results showed that Guwela s/c had high
disease incidence and the lowest disease severity as compared to the other two
service centers. The lowest disease incidence was observed at Hlaneki s/c whilst
Mhlava willem s/c had the highest disease severity. The two water treatments (full and
deficit irrigation) in both farms have shown no significant pairwise differences among xx
the volumetric water content means. There was no significant difference (P≥0.05) in
early blight disease severity in both farms. Results shows that, all tomato varieties did
not differ significantly (P≥0.05) in yield observed between treatments at Duvadzi and
A hi tirheni Mqekwa Farm. Deficit irrigation can be used effectively to produce high
yields in tomato production provided the cropping season window does not coincide
with the hottest time of the year. Full and deficit irrigation did not have influence on the
early blight disease incidence on tomato plants.
Key words: Alternaria solani; disease incidence; disease severity and drip irrigation
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:ul/oai:ulspace.ul.ac.za:10386/3349 |
| Date | January 2020 |
| Creators | Lebea, Tebogo Johannes |
| Contributors | Kena, M. A., Jovanovic, N. |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Type | Thesis |
| Format | xx, 111 leaves |
| Relation |
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