60Co γ辐照与NO复合处理对杂交石斛类原球茎生长和生物碱合成的影响

摘要：以杂交石斛类原球茎为材料，硝普钠（sodium nitroprusside, SNP）为NO的供体，研究了60Co γ辐照和ＳＮＰ复合处理对石斛悬浮培养类原球茎的生长和生物碱合成的影响。结果表明，60Co　γ和ＳＮＰ单独或复合处理都能促进类原球茎生物碱的合成，且复合处理对石斛类原球茎生物碱的合成有一定的累加效应, 但类原球茎生长减缓。适宜的复合处理组合为01mmol/L SNP+10Gy60Co γ辐照，此时类原球茎生物碱含量高达00676%，与各因素单独处理差异显著，单位培养基生物碱产量为对照组的635倍。NO抑制剂L NAME和cPTIO均能抑制各处理组合对类原球茎生物碱合成的促进作用。复合处理影响类原球茎抗氧化酶POD、SOD、CAT活性，从而调控石斛类原球茎生长和生物碱合成。

BIOLOGICAL AND PHOTOSYNTHETIC CHARACTERISTICS OF LOW PHYTIC ACID MAIZE INBRED LINE MUTANT

In this paper, the main biological characteristics and photosynthetic rate of low phytic acid (LPA) maize mutant and its wildtype were compared through field experiment and nutrient solution culture experiment respectively. The results showed that, compared with wildtype, many changes had taken place in low phytic acid maize mutant. For example, the durations from seeding to tasselling and from seeding to silking were prolonged; the leaf area was diminished; the shoot and root dry matter weight were all reduced; root shoot ratio was increased; chlorophyll SPAD value was reduced, however, the net photosynthetic rate was increased. Furthermore, the countermeasures and proposals about the breeding improvement using low phytic acid maize were suggested according to the biological characteristics of low phytic acid maize mutant.