荔枝和龙眼种子胚轴的脱水及贮存

新采收的荔枝和龙眼种子的离体胚轴,在pH4.8 8.0的WPM培养基中均可正常生长成苗,加入KT和NAA对胚轴的生长有—定的抑制作用。荔枝和龙眼种子离体胚轴的临界含水量分别为30％和23％,低于此阈值时,生活力迅速下降,且培养25天不能成苗。经短期贮存的荔枝和龙眼种子离体胚轴生活力下降很快,其中脱水的较未脱水的胚轴下降快,且贮存后的胚轴接种后易感染。脱水至临界含水量的龙眼离体胚轴经液氮贮存后约有25—50％的存活率,荔枝胚轴则不能存活。

THE DESICCATION AND STORAGE OF EMBRYONIC AXESOF LYCHEE (LITCIII CHINENSIS SONN. ) AND LONGAN(DIMOCARPUS LONGAN LOUR. ) SEEDS

Embryonic axes excsied from fresh lychee and longan seeds could be cultured and developed into plantlets in non-hormonal WPW medium with pH4. 8-8. 0. The addition of NAA and KT to the medium caused the inhibition on the normal growth of embryonic axes. The critical moisture contents of the embryonic axes of lychee and longan were about 30% and 23% respectively. Desiccation beyond these thresholds, the viability fell rapidly, and the embryonic axes could not produce normal plantlets after incubation for 25 days. The viability of embryonic axes desiccated by silica gel decreased more quickly than that of non desiccated ones after short-time storage , and the embryonic axes were easily infected by bacteria during incubating. The survival percentages of lychee and longan embryonic axes desiccated to about the critical moisture contents were 0 and 25-50%, respectivity, when they had been storaged in liquid nitrogen for 24 hours.