杉木组培嫩梢增殖与复壮的分析

用取自1、5和10年生母本上的杉木茎段作为原始外植体,接种于含有BAP 0.75mg/l和IBA 0.25mg/l的“GN”培养基中(NH_4~+:NO_3~-=1∶2.86)。经1a连续4代培养,结果表明:嫩梢及苗木产量因外植体母本的年龄不同有很大差异。如母本年龄为1a的外植体,每个平均可获嫩梢170.3—445.7根,其中有效嫩梢78.0—194.9根,包括Ⅰ级(好的,可供继代培养继续增殖)11.1—25.1根;Ⅱ级(中等,可供生根培养以成苗)36.1—87.9根;Ⅲ级(须继续培养)29.5—78.6根。随着原始外植体母本年龄的增加,以上各项数值都相应下降。 另一方面,由于组织培养对于成年母本的外植体具有不同程度的复壮效应,使得嫩梢增殖效果差异很大。如取自年龄为5、10年生母本上的外植体,平均年嫩梢产量为4.1—234.3根,如此大范围的变化为培养体的复壮选择提供了可能性。 此外,本文还对嫩梢增殖的生产效应作了初步分析。

AN ANALYSIS OF SHOOT MULTIPLICATION AND REJUVENATION OF CHINESE-FIR IN VITRO

Segments of stem cutting from 1- 5-and 10-year-old Chinese fir (Cunninghamia lanceolata) were cultured in vitro on GN (NH4+:NO3- = 1:2.86) medium containing BAP (0.75mg/l) and IBA (0.25mg/l). After four successive subculture lasted for one year, the results show that there is a great difference in yields of shoots and nursery stocks due to different ages of maternal plants of the explants. For example, an explant which was one year old obtained 170.3-445.7 shoots on average, including 78-194.9 efficient shoots. Among these shoots there were 11.1-25.1 shoots of 1 degree (advanced, able to be on subculture); 36.1-87.9 shoots of 2 degree (moderate, able to be rooted) and 29.5-78.6 shoots of 3 degree (to be needed to subculture). And it is estimated that the yield of nursery stocks can reach 34.7 on average. With the increase of ages of maternal plants of the explants, the above data decreased. However, the yield of shoots per explant, 5- and 10-year-old, was 4.1-234,3 because of an effect of rejuvenation in vitro as well as a great difference in shoot multiplication. Thus, there is a possibility in selecting rejuvenated cultures. Besides, this paper put forward a preliminary analysis on the effect of production of shoot multiplication.