Growth responses of Tomato (Lycopersicon Esculentum Mill)to different growing media under Greenhouse and field conditions

Green houses provide opportunity for year round crop production. Although tomatoes are an option for utilizing greenhouse space, performance of tomato under these conditions has potential limitations which may include root restriction and its attendant impacts such as artificial media effects on varietal characteristics. Decline in profitability of rose production for which greenhouses in Zambia were used has left excess capacity. Tomatoes provide a profitable
option for farmers. A study was conducted was to evaluate growth responses of tomato grown in different growing media under controlled environment (greenhouse) and Field conditions of three tomato varieties (Star 9030, Tengeru and Rodade) under different growing media (Peat in
sleeve, Coccus in sleeve, Coccus in trough, Soil in sleeve and Soil bed). The experiment was conducted at the Natural Resources Development College in Lusaka between May to October 2011. Two experiments were carried out; the first one was a Greenhouse study under an open sided naturally ventilated Plastic greenhouse. The experimental design adopted was a Split plot design where, varieties were assigned to the main plots and the media to subplots. The field
experiment involved the same varieties planted directly into the soil but used a Randomized Complete Block Design. The parameters measured included vegetative variates i.e. plant height and root/ canopy ratio; reproductive variates were; total fruit number per plant and total yield.
Fruits were harvested at breaker stage when the skin colour was 30% pink red. Fruit quality parameters including shape (indicated by the ratio of fruit diameter to height) and Brix (Total soluble solutes content). The results from the study showed that: In the greenhouse Star 9030 grown in soil bed grew taller than the other 2 varieties. The trend of these results was significant from 4 weeks after transplanting. The total fruit number and weight of Star 9030 grown in soil
bed (29 and 19.5t/ha) was significantly higher than Rodade (14 and 8t/ha) and Tengeru (24 and 15t/ha) compared to other media (p ≤ 0.001), whilst the root: shoot ratio was not significant different among the cultivars and media. The total soluble solid content expressed as Brix was
significantly different between varieties, Tengeru with 5.0 was highest followed by Star 9030 with 4.0, Rodade with 3.5. ). Fruit diameter: height ratio was not different between Rodade and Tengeru but significantly lower than Star 9030 whilst the effect of media showed no significant
differences. In comparison to the greenhouse results, the field experiment performance was as follows; the mean fruit weight was; Star 9030 (12 t/ha), Rodade (5 t/ha) and Tengeru (10 t/ha) whilst total soluble content at 4.7 for Star 9030, 3.5 for Rodade and 3.7 for Tengeru was not significantly different among the different varieties .