Understanding nutrient competition between Echinochloa spp. and Oryza sativa L.
Weed competition in southern Brazil is one of the main limiting factors for Oryza sativa L. (flooded rice) yield. Echinochloa spp. (barnyardgrass) occurs at a high frequency. Although the potential for weed interference in this cereal is well known, there is little information available about the...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Polish Academy of Sciences
2020-08-01
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| Series: | Journal of Plant Protection Research |
| Subjects: | |
| Online Access: | https://doi.org/10.24425/jppr.2020.133320 |
| Summary: | Weed competition in southern Brazil is one of the main limiting factors for Oryza sativa L.
(flooded rice) yield. Echinochloa spp. (barnyardgrass) occurs at a high frequency. Although
the potential for weed interference in this cereal is well known, there is little information
available about the impact of nutrient competition on rice. Thus, this study aimed to evaluate
the relationship between the increase of the barnyardgrass population and the development
and nutrition of flooded rice plants at different stages of development. The treatments
consisted of growing populations of barnyardgrass competing with the crop from stage V4,
which were: 0, 1, 6, 13, 100 and 200 plants · m−2. The experimental design was randomized
blocks with two replications, and the experimental units were plots 1.53 m wide by
5 m long. Plant biomass, nutrient uptake and loss of productivity were determined with
three replications. An increase in the barnyardgrass population reduced the dry mass of
rice leaves and stems, regardless of the evaluation period and the vegetative or reproductive
period. Barnyardgrass plants had a significant impact on the reduced grain yield of
a flooded rice crop, mainly due to high nutrient competitiveness, especially N in the vegetative
period and K in the reproductive period. Barnyardgrass caused a loss of yield by
unit · m−2 of 1.13%. The competition for N between rice and barnyardgrass plants was
higher in the vegetative period, while for K, Ca and Mg the highest competition occurred
in the reproductive period. |
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| ISSN: | 1899-007X 1899-007X |