Genetic Diversity of Rumex k-1(Rumex patientia×R.tianschanicus cv.Rumex k-1) and Wild Rumex spp. Research on the Agronomy Characters of Three Continued Generations of Rumex patientia×R.tianschanicus cv. Rumex K-1 SELECT OF MODEL AND RECOMMENDATION OF NITROGEN FERTILIZATION FOR RUMEX K-1 HYBRID DOCK EFFECT OF RERTILIZER N RATE ON NITROGEN UTILIZATION AND BALANCE OF RUMEX K-1 HYBRID DOCK