春季低温对紫叶小檗和朝鲜黄杨苗木生长的影响

[目的]研究春季低温对苗木生长的影响。[方法]以一年生紫叶小檗和朝鲜黄杨扦插苗为试材,于春季芽膨胀期和展叶初期2个阶段设置了0、-2、-6℃3个温度水平,分别持续1、3、6 h处理,以自然条件为对照,研究冷冻温度与低温持续时间对苗木的成活率、植株生长量、根茎叶的干物质含量以及根冠比等指标的影响。[结果]结果表明:保定地区脱锻炼期间温度降至-2~0℃时,不需要防寒措施,两种苗木便可安全度过霜期;但降到-6℃,则有必要采取保护措施。[结论]该研究为北方地区在春季遭遇晚霜等冻害的情况下,确定和采取防护措施具有重要的指导意义。

Influences of Low Temperature on Berberis thumbergii f. atropurpurea and Buxus microphylla var. Koreana in Spring

[Objective] The purpose was to research the influence of low temperature in spring on seedling growth.[Method] With one-year-old cutting seedlings of Berberis thumbergii f.atropurpurea and Buxus microphylla var.koreana as test materials,they were exposed to the temperatures at 0 ℃ for 1 h,-2 ℃ for 3 h and-6 ℃ for 6 h resp.in two periods of bud-expansion and initial leaf-expansion in treatments.With the seedlings in nature as CK,the influences of freezing temperature and low temperature duration on the indexes such as survival rate,plant growth and dry matter contents in roots, stems and leaves,as well as ratio of root to shoot were studied.[Result] The results indicated that when the temperature dropped to-2～0 ℃ in the deacclimation stage in Baoding,it was not necessary to take cold-proof measures for these two kinds of seedlings,as they could get through frost season safely.However,when the temperature dropped to-6 ℃,it was necessary to take protective measures for them.[Conclusion] The research was important to confirm and take protective measures under the conditions that the seedlings met the freezing injury such as late frost in the north in spring.