Growth and Yield Responses of Leafy Vegetables Grown in Organic and Conventional Agriculture Systems

Abstract

Several scientific reports indicate lower as well as higher relative yield stability in organic and conventional (chemical) agriculture systems. This study presents the results of on-farm trials conducted on leafy vegetables grown in organic and conventional management systems. Four leafy vegetables collard green (Brassica oleracea cv. acephala), kale (Brassica oleracea cv. sabellica), lettuce (Lactuca sativa) and swiss chard (Beta vulgaris L. cv. cicla) were grown in organic and conventionally managed plots in the spring 2018 and 2020. United States Department of Agriculture (USDA), National Organic Program (NOP) standards were followed for cultural and management practices in organically managed experimental field plots. Synthetic chemical fertilizer was applied in the experimental field plots managed in the conventional production system. Data on plant height, leaf number and total fresh weight of leafy vegetables were measured at the end of the experiment. There was no difference in plant height and number of leaf count between the two production systems for all four crops. Collard was the tallest in the organic system in both years, kale in 2018 and collard in 2020 were tallest in the conventional system while lettuce was the shortest in both the production systems. In terms of leaf number, organic kale had the highest leaf number; however, all other crops have the same number of leaves. In organic production, lettuce fresh weight was significantly higher than the collard and similar to the rest of the crops. In conventional production, kale fresh weight was significantly higher followed by collard, swiss chard and lettuce. Moreover, lettuce fresh weight was significantly higher in organic than conventional system, no difference was recorded for swiss chard between two systems while collard and kale fresh weight was significantly higher in conventional than organic production. Our results suggest that the organic system can be a best choice for lettuce and conventional system is best choice for collard and kale.

Productivity and Constraint in Multipurpose Tree Species Cultivation: A Case Study from Cilimus Village, Wan Abdul Rachman Forest Park, Indonesia

“…In the context of plant pests and diseases, climate change will also affect the incidence of disease and the occurrence of pest attacks on MPTS plants cultivated by farmers in Tahura WAR. Climate directly affects the bioecology of insect pests, such as drastic climate changes, which will disrupt the insect breeding process (decrease or increase) [22]. To reduce the risk of pest and disease attacks on MPTS plants, farmers are expected to select and plant quality MPTS plant seeds so that they can adapt to existing conditions.…”