Critical Period of Weed Competition in Curcuma Lanna Snow Field

Abstract

The effects of weeds on crops can cause weed interference, which is the result of their competition with each other. The influence of weed interference periods on growth and inflorescence of Curcuma was investigated under field experiment. The critical period for weed control consists of the increased duration of weed competition period during the weed-infested treatment, and the increased duration of weed free period during the weed-free treatment. Weed-free and weed-infested treatments were used to identify the critical period for weed control with acceptable yield loss of 5 and 10%. The results revealed that weed infested periods at 10, 12, 14 and 16 weeks after planting and weed free periods at 0, 2 and 4 weeks after planting significantly reduced the leaf number, height of inflorescence, width of inflorescence and length of inflorescence of Curcuma, while plant height was slightly affected by weed-free treatment. In addition, the critical period for weed control with 5 and 10% acceptable yield loss was estimated to be between 6 to 10 weeks after planting and 5 to 8 weeks after planting, respectively. The critical period for weed control at 10% acceptable yield loss was shorter than the critical period for weed control at the level of 5%. However, the determination of appropriate critical period for weed control should be concerned to have better crop yield and reduce cost. Weed control estimation and recommendations can enhance more precise weed management, which is helpful in formulating appropriate weed-control strategies in Curcuma fields.