**3.1. Effects of agricultural practices on phytochemicals in fruits and vegetables**

Undisputedly, the introduction of pesticides (synthetic) like insecticides and herbicides in the period between 1970 and 1980 contributed to increased agricultural productions. However, this intervention in agriculture has had some unintended results toward human life. The criticism of the usage of pesticides is mainly based on their direct cause of fatal health challenges and chronic diseases due to their poisonous effect upon exposure [10]. However, in addition, the potential consequences of the limitations in the phytochemical accumulations by agricultural plant products are not being given adequate attention or canvassing in the public discourse.

The effect of pesticide application on the phytochemical accumulation in fruits and vegetables could be assessed through the comparison of phytochemical quantities between crop products produced through organic farming, which does not involve the use of synthetic pesticides, and those produced through conventional farming that uses synthetic pesticides. In this regard, organic farming was reported to have been given yield to sweet pepper (*Capsicum annum*) of higher intensities in color (both red and yellow); higher mineral contents and higher total carotenoids than those produced through conventional farming [11]. In addition, the same study reported that highest antioxidant activity was found in red peppers produced through organic farming. In a separate study, a higher ratio of reducing sugars/organic acids, as well as high amounts of total sugars, vitamin C, and total flavonoids were recorded in tomato fruits produced by organic farming compared to those of conventional farming practice [12]. According to Oliveira et al. [13], the accumulation of more phytochemicals such as phenolics and vitamin C in tomato fruits from organic farming was a result of the stressing conditions associated with the farming system. It thus follows that conventional farming practice reduces or remove stressful growing conditions that then limit the accumulation of important phytochemicals in crops. The demonstration through some studies that the production of food products through conventional farming methods with the excessive use of insecticides and herbicides may limit the accumulation of phytochemicals in fruits and vegetables necessitate the assessment of potential implications of such limitations on people's health.

The quality and quantity of phytochemicals in plants depend on a number of factors that include the growing environment. Organic farming inherently provides a different growing environment compared to conventional farming, which relies heavily on inputs such as pesticides, synthetic fertilizers, and excessive irrigation. The growing environment in organic farming exposes plants and crops to biotic stress due to pests and diseases [14]. Herbivore and pathogen attack lead to enhanced biosynthesis and accumulation of defense-related phytochemicals in fruits and vegetables [15]. Deficiency of nitrogen, phosphate, and iron that emanate from non-application of synthetic fertilizers in organic farming contribute to the accumulation of phenolic compounds in fruits and vegetables [15]. Drought or less irrigation associated with organic farming also induce accumulation of polyphenols and total tannins in crops through the activation of the phenylalanine ammonia-lyase enzyme that is involved in the biosynthesis of phytochemicals in plants [16].
