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研究表明，马唐的生育期为６２—１１１天，需＞０℃积温１３８０—２７１６。其生殖生长阶段对季节的温度要求严，营养生长阶段宽，生育期长短主要靠营养生长期的长短来调节。马唐种子休眠期一般为１５０天，休眠期长短和解除休眠速率与种子贮藏条件关系密切，以恒温贮藏最快。种子发芽起点温度为１５℃，６０％种子发芽的有效积温平均为５５５．１３℃。马唐种子发芽对光照要求不敏感。在农田７ｃｍ土层内的种子均能出苗，但以１—４ｃｍ层最佳。马唐的再生能力强，试验表明，凡是带有须根和幼芽的任何断节都能发生新的植株。通径分析结果表明，马唐是我国北方夏播粮田的主要杂草。马唐群体水平（ｘ，株／ｍ￣２）与夏玉米籽粒减产率（ｙ，％）间呈以下关系模式：（１）ｙ＝０．１５３２ｘ￣（１．５５７４）（ｘ≤２０株／ｍ￣２）（２）ｙ＝－１８．４００＋１１．３１５ｌｎｘ（ｘ＞２０株／ｍ￣２）与夏玉米共同生长日数对作物籽粒减产率呈以下关系模式：ｙ＝５４．５９５６／ｌ＋８９．７９６２ｅ￣（－０．１１８４ｘ）根据推算，在石家庄地区夏播玉米田，马唐的允许存在密度即生态经济阈值为５．８株／ｍ￣２。
Studies have shown that the growth period of Crabgrass 62-111 days, need to> 0 ℃ accumulated temperature 1380-2716. Its reproductive growth stage of the temperature on the strict requirements of the vegetative growth stage, the length of growth depends mainly on the length of vegetative growth period to adjust. Crabgrass seed dormancy is generally 150 days, the duration of dormancy and release of dormancy rate and seed storage conditions are closely related to the fastest storage temperature. The starting temperature of seed germination was 15 ℃, and the effective accumulated temperature of 60% seed germination was 555.13 ℃. Crab seed germination is not sensitive to light requirements. Seeds in the 7 cm soil layer can emerge, but the best 1-4 cm layer. Crabgrass has a strong regenerative capacity and tests show that new plants can occur in any section with fibrous roots and buds. Path analysis showed that Crabgrass was the main weed in summer sowing grain fields in northern China. (1) y = 0.1532x ~ (1.5574) (x≤20 plants / m ~ 2) and summer maize grain yield (y,%) m ~ 2) y = -18.400 + 11.315lnx (x> 20 plants / m ~ 2) and summer maize growth date on crop grain yield rate was the following relationship model: y = 54.5956 / l 89.7962e ~ (-0.1184x) According to the projections, in Shijiazhuang summer sowing field, the allowed density of crab that ecological and economic threshold of 5.8 strains / m ~ 2.