Impact of Row Covers on Yield Performance, Sensory and Phytochemical Analysis of Leafy Green Vegetables Grown in Organic Management System
Row covers are gaining interest in crop production for their potential to protect crops from insect pests, frost, increase soil and air temperature, and extend growing season, thus producing higher crop yield. However, research on the performance of green leafy vegetables grown under row cover in organic management system is scarce. The field trials were conducted in the spring 2018, 2019 and 2020 (February–May) to analyze the growth and yield responses of leafy greens (collard, kale, lettuce and swiss chard) in row covers as well as to analyze sensory attributes, phytochemical qualities and soil properties of leafy greens grown at organic and conventional management at the Tennessee State University Nashville, TN. Results showed that fresh weight per plant significantly (P < 0.05) increased under agribon cloth in kale, swiss chard and collard, while lettuce produced significantly higher yield under insect net relative to open (control) in the 2018 whereas in 2019, swiss chard and collard yield was higher under plastic, and lettuce yielded higher under agribon cloth and kale under insect net compared to open. Similarly, in 2020 the fresh weight of leafy greens was higher (P < 0.05) under row covers. In comparing the yield of leafy greens from organic and conventional management, maximum fresh weight per plant was obtained from conventionally grown kale and the lowest was recorded for conventionally grown lettuce. For lettuce, significantly greater fresh weight was obtained in the organic compared to conventional and no difference in fresh weight between organic and conventional production for swiss chard. All differences in the sensory qualities between the two production systems do not create major sensory differences in the leafy greens vegetables evaluated. Further studies are needed to confirm and investigate the consumer preference towards organic products growing under different row covers. The Vitamin C content of leafy greens were significantly reduced after 10 and 20 days of storage at 4 °C in both organic and conventional management but for DPPH (2, 2-diphenyl-1-picrylhydrazyl) free radical scavenging activity and reducing power, there was no significant changes in 10 days but after 20 days it was numerically reduced. Organic production system promoted microbial biomass governed by the elevated carbon use efficiency and limited soil heterotrophic respiration to the atmosphere. Thus, row covers are a viable option in sustainable production of leafy greens for organic vegetable growers to grow crops earlier in the season.
"Impact of Row Covers on Yield Performance, Sensory and Phytochemical Analysis of Leafy Green Vegetables Grown in Organic Management System"
ETD Collection for Tennessee State University.