Effect of water regimes on weed competition in upland rice (Oryza sativa) (Philippines)
1984
Janiya, J.D. | Moody, K.
Rice had higher nitrogen content but lower nitrogen uptake than the weeds. The nitrogen content of rice was unaffected by competition from weeds but nitrogen uptake increased when weeds were controlled. The leaf water potential of rice drastically decreased at soil moisture contents below 16 cm soil depth while in the unweeded plots it extended below 30 cm. However, soil water loss was greater in the weed free plots than in the unweeded plots. Water loss was higher at high soil water content and decreased with decrease in soil moisture content. Significantly yield increases were obtained with one hand weeding at high soil moisture contents but not at low soil moisture contents
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