PERFORMANCE OF TOMATO CULTIVARS IN TEMPERATURE AND NON- TEMPERATURE CONTROLLED PLASTIC TUNNELS
The majority of tunnel production in South Africa is carried out in standard (non-temperature controlled) tunnels, while utilization of temperature controlled tunnels is increasing. Knowledge on the performance of common tomato cultivars utilizing tunnels is still very limited. Four tomato cultivars, namely, FA593, Malory, Miramar and FiveOFive were grown in an open-bag system with sawdust as growing medium in non-temperature controlled and temperature controlled tunnels. The latter was equipped with a fan-and-pad cooling system, while the non-temperature controlled tunnel relied on natural ventilation. A randomised complete block design with four cultivars replicated four times was used for both conditions. Fruit number and mass, as well as total marketable and unmarketable yield per plant were calculated for each cultivar. Miramar and FiveOFive produced the highest marketable yield in both structures. The average marketable yield was 88 and 59% of the total yield in the temperature controlled and non-temperature controlled tunnel, respectively. All cultivars produced a higher marketable yield in the temperature controlled tunnel than in the non-temperature controlled tunnel. The lower marketable yield in the non-temperature controlled tunnel was caused by the higher number of small-sized fruits and higher number of fruit cracking. This disorder was found to be directly correlated with fruit size, with cultivars Malory and FA593 more susceptible than the other two cultivars. Results emphasize the importance of cultivar selection, while illustrating that temperature control can improve yield and quality of tomatoes produced in tunnels.
Maboko, M.M., Du Plooy, C.P. and Bertling, I. (2012). PERFORMANCE OF TOMATO CULTIVARS IN TEMPERATURE AND NON- TEMPERATURE CONTROLLED PLASTIC TUNNELS. Acta Hortic. 927, 405-411
cultivar, fruit cracking, fruit size, temperature, tunnel, quality, yield