EFFECT OF NATURAL SOIL FERTILITY ON Lycopersicon esculentum (TOMATO)
CHAPTER ONE
INTRODUCTION
Tomato (Lycopersicon esculentum Mill.) constitutes one of the most valuable horticultural crops, not only because of its economic importance, but also for its sensory qualities and nutritional value. It is consumed in the form of fresh as well as processed products. More than 80% of tomatoes grown throughout the world are processed into products such as sauce, juice, ketchup, canned tomato, stew and soup (Viskelis et al., 2015). Epidemiological studies have proved the importance of tomato and its products in reducing various ailments because they contain high amounts of antioxidants such as carotenoids, polyphenols, ascorbic acid and many others (Perveen et al., 2015). Lycopene is the most plentiful carotene in the tomato fruit, comprising up to 90% of the total carotenoids present (Viskelis et al., 2015), and is the most important antioxidant with a high oxygen free radical-scavenging and quenching capacity, and thus provides protection against chronic diseases, such as several types of cancer, including cancer in the mouth, pharynx, esophagus, stomach and large intestine, and cardiovascular diseases (Perveen et al., 2015). Lycopene is also the pigment mainly responsible for the red colour of tomato fruits.
Various studies have reported that the lycopene content in tomatoes is most notably influenced by various genetic and environmental factors, such as the cultivar, growing season, cultivation conditions and harvesting stage (Toor et al., 2006; Rickman Pieper and Barrett, 2008). Successful production of processing tomato requires to increase both yield and fruit quality. There has been a substantial research effort devoted to the processing tomato; however, it is not clear how the environment, cropping techniques and crop management affect each of the fruit characteristics measured at harvest to estimate the quality of processed products. In addition, during the last decades, the demand for organically grown products has increased because many people are concerned about the environment and believe that organic products are healthier than the conventional ones (Riahi et al., 2009).
Several experiments investigating the