通常人们认为,多年生黑麦草(Loliumperenne L.)耐寒力差(Beard,1973;Turgeon,1980),因此在冬季比较寒冷的地区,它的利用已受到很大的限制。但最近据苏联的一些考查者报道,黑麦草生长的原产地冬季十分寒冷(Funk,1980)。又有人报道,目前栽培地区选出的许多新良种,其耐寒力已得到提高。我们需要这些品种具有很强耐寒力的资料,以便把它们引入北方。由于变化莫测的气候条件,要获得准确的田 It is generally believed that perennial ryegrass (Lolium perenne L.) has poor cold tolerance (Beard, 1973; Turgeon, 1980) and therefore its use has been severely limited in colder winter regions. But recently, according to some investigators in the Soviet Union, the origin of ryegrass is very cold in winter (Funk, 1980). Others reported that the cold hardiness of many new varieties selected in the current cultivation areas has been raised. We need information about the strong cold hardiness of these species in order to bring them to the north. Due to unpredictable climatic conditions, to obtain accurate field