Department of Agricultural Chemistry, The University of Tokyo, Bunkyo-ku, 113, Tokyo.
Planta. 1979 Jan;146(2):185-91. doi: 10.1007/BF00388230.
The major endogenous gibberellin (GA) in shoots, roots and ears of the rice plant, Oryza sativa L. japonica cv. Nihonbare, was identified as GA19 by combined gas liquid chromatography-mass spectrometry (GC-MS) and GC-selected ion current monitoring (GC-SICM). Another GA present in these tissues in small quantity was tentatively identified as GA1 by GC-SICM, and GA4 may be present in the seeds (kernels) of 3rd-leaf-stage seedlings. Using GC-SICM, the GA19 content was quantified throughout the life cycle of rice plants. It was found to reach high levels (ca. 10-15 μg/kg fresh weight) in 3rd-leaf seedlings, at panicle initiation (shoots), and during heading and anthesis (ears). The levels of GA19 in Oryza sativa indica cv. T-136 underwent changes closely similar to those found in Nihonbare. The growth-promoting activity in rice of exogenous GA19 is generally considerably less than that of GA1. It therefore seems possible that GA19 functions as a "pool GA". The level of active GAs such as GA1 may be regulated by the rate of biosynthesis of GA19 or its metabolic conversions.
在水稻植株的茎叶和根中，主要的内源性赤霉素（GA）被鉴定为 GA19，这是通过气相色谱-质谱联用（GC-MS）和 GC-选择离子流监测（GC-SICM）联合分析得到的。在这些组织中，还存在少量的另一种 GA，通过 GC-SICM 初步鉴定为 GA1，GA4 可能存在于三叶期幼苗的种子（谷粒）中。利用 GC-SICM，对水稻植株整个生命周期中的 GA19 含量进行了定量分析。结果表明，在三叶期幼苗、穗起始期（茎叶）、抽穗期和开花期（穗）中，GA19 的含量达到了较高水平（约 10-15μg/kg 鲜重）。在籼稻品种 T-136 中，GA19 的水平变化与在 Nihonbare 中发现的变化非常相似。外源 GA19 在水稻中的生长促进活性通常明显低于 GA1。因此，GA19 可能作为一种“池 GA”发挥作用。像 GA1 这样的活性 GA 的水平可能受到 GA19 生物合成的速度或其代谢转化的调节。
