Effect of optimized nitrogen rates and intercropping okra with mungbean on crop nutrient uptake
Creators: name: A, Wen
name: Pawera L
Publisher: name: World Vegetable Center
Year: 2024
Subjects: subject: NITROGEN FERTILIZERS
subject: OKRA
subject: INTERCROPPING
subject: VEGETABLE LEGUMES
subject: SUSTAINABILITY
subject: FIELD TRIALS
subject: HEAVY METALS
subject: HUMAN HEALTH
subject: Nitrogen fertilizer rates
subject: Vegetable production
subject: Okra growth
subject: Okra yield
subject: Okra quality
subject: Intercropping
subject: Legumes (mungbean)
subject: Agroecological practice
subject: Nutrient use efficiency
subject: Field experiment
subject: Split-plot design
subject: Nitrogen application rates (0%, 50%, 100%)
subject: Intercropping patterns (okra monoculture, mungbean monoculture, mixed intercropping, row intercropping)
subject: Leaf sampling
subject: Analysis of variance
subject: R software version 4.4.1
subject: Tukey HSD test
subject: Optimum nitrogen rates
subject: Mungbean intercropping
subject: Nutrient uptake
subject: Heavy metal absorption
subject: Plant and human health

description: Nitrogen fertilizer rates are crucial in vegetable production, as inadequate and excessive nitrogen can negatively impact okra growth, yield, and quality. Intercropping vegetables with legumes like mungbean is an agroecological practice that could partially substitute synthetic nitrogen fertilizers use and increase nutrient use efficiency. This study aimed at evaluating the effects of different okra + mungbean intercropping patterns and nitrogen rates on nutrient uptake. A field experiment was conducted at the World Vegetable Center in Taiwan from April to July 2024. The trials used a split-plot design in three replications. Treatments included three N-application rates (0%, 50%, and 100% of the farmers recommended rate) as the main plot factor. The sub-plot factor comprised of four intercropping patterns: okra monoculture, mungbean monoculture, okra + mungbean mixed intercropping, and okra + mungbean row intercropping. Leaf samples for both okra and mungbean was collected from the field at harvest. Samples preparation was done at World Vegetable Center and was later taken to Tainan DARES (District Agricultural Research Extension Station) laboratory for analysis. Data was subjected to analysis of variance using R software version 4.4.1 to identify the differences among nitrogen rates and intercropping patterns. Means, where different were separated using the Tukey HSD test at a 5% level of significance. This study aimed at investigating optimum nitrogen rates for okra production and the use of mungbean intercropping as a complementary nitrogen supply strategy. Mixed intercropping demonstrated a higher nutrient uptake rate compared to row intercropping, though the difference in certain element absorption was not significant. As expected, mungbean showed very low absorption of heavy metals, a positive outcome for plant and human health. Both N50 and N100 nitrogen application rates were effective for nutrient absorption in both crops, with no significant difference between them, indicating that nitrogen rates can be reduced to N50 without compromising nutrient uptake.