Effect of Medium Culture, pH, Activated Carbon, and Light on Germination, Rooting and Growth of Tomato (Lycopersicum Esculentum Mill.)

This study was carried out to compare germination rates, rooting, and growth of three varieties of Lycopersicum esculentum Mill.namely Rio Grande, Campbell 33 and Assala under different growing conditions (greenhouse, petri dish and in vitro culture), as well as a study of the influence of growing medium, light, activated carbon and pH.The seeds were disinfected before being grown under different conditions.For greenhouse cultivation, a sand/peat mixture (50/50) was used.The germinated seeds were monitored regularly under controlled conditions.For the petri dish culture, seeds were germinated on moistened sterile filter paper.As for the in vitro culture, the seeds were grown on MS and ½ MS medium.Activated carbon was added in order to study its effect on germination at a concentration of 5g/L.They were then incubated in the absence or presence of light.Concerning the effect of pH, five values were tested (4,2 -5-5,8-7-10).The analysis of the quantitative data revealed that the variety Rio Grande has a high germination capacity compared to Campbell 33 and Assala.Regarding the cultivation conditions, the results showed that in vitro cultivation gave the best germination rate (79.66%).In this case, incubation in the dark was considered more effective than light as it ensured a higher rate (76.99%).In addition, ½ MS medium promoted the root system of the seedlings by accelerating the speed of appearance of adventitious roots and their number compared to the MS medium.This same effect was also observed in the presence of activated carbon.The results also indicated a direct effect of the pH of the medium on germination.Indeed, pH 5.8 was advantageous for the Rio Grande and Assala (95.99% and 75% respectively).For the Campbell 33, pH 7 was more suitable than the other pH tested (81.66%).This work suggests that in vitro culture is a promising tool for improving the yield of this plant and the resulting in vitro plants can be used as source material for molecular biology.