The impact of different crop production systems was investigated on incidence of insect pests and their natural enemies, soil microflora and enzymatic activity, and quality of fruits produced in spring planted tomato at Ludhiana, Punjab, during 2017 to 2019. Production systems included conventional farming whereby indiscriminate and excessive use of agrochemicals is practiced, organic farming, and farming following Good Agricultural Practice (GAP) with IPM adoption. Higher Aphis gossypii and Helicoverpa armigera infestation was observed in organic fields followed by IPM and conventional fields. Aphid population showed a negative correlation with maximum and minimum temperature but a positive correlation with relative humidity, while the tomato fruit borer showed a positive correlation with maximum and minimum temperature but negative correlation with relative humidity and rainfall. The mean fruit yield in the farming system following IPM was maximum (50120 Kg ha-1) followed by conventional farmers' fields (408.1 q/ha) and organic fields (403.9 q/ha). The mean spider population under organic conditions (0.39-0.56) was significantly higher than that of IPM (0.26-0.36) and conventional farmers' fields (0.02-0.10). Soil samples from conventional fields revealed the presence of quinalphos and chlorpyriphos, while tomato fruit samples showed the presence of triazophos and mancozeb during 2017 and 2018. In 2017, the flavonoids and percent antioxidant activity in fruits from organic field were higher. The bacterial count in organic and IPM field soil increased from 5.4x107 and 4.9x107 CFU g-1 in 2017 to, respectively, 7.1x107 and 6.5x107 CFU g-1 in 2019. The activity of alkaline phosphatase and urease was highest in organic fields.
