大麦籽粒植酸及其他相关化学组分的动态变化

Dynamic changes of phytic acid and other related chemicals in barley grains

应用MMF方程对3个大麦品种籽粒发育期间的植酸累积过程进行拟合分析，并研究其与蛋白质、总磷含量动态累积之间的关系．结果表明：籽粒发育期间，供试大麦品种的植酸含量随时间变化过程符合“s”型曲线，累积速率变化则呈“慢一快一慢”的单峰曲线，累积高峰出现在花后13～14d；不同大麦品种的植酸累积特征存在着一定的差异，裸大麦品种CAW453的植酸累积持续时间较2个皮大麦品系（03—34和06—08）短，但其累积速率的变化幅度较大．相关分析结果表明：籽粒发育期间植酸含量和粒质量变化之间呈显著正相关；植酸累积动态并不受蛋白质和总磷含量的影响，其合成速率与蛋白质、总磷累积速率之间关系不密切．本研究结果显示，大麦籽粒中植酸和磷的累积机制可能彼此独立，在大麦籽粒发育期间可能存在着比植酸合成更为活跃的其他磷代谢行为．

Three barley genotypes, differing in phytic acid （PA） content were field-grown, and the dynamic changes of PA, protein and total phosphorus （P） contents as well as grain mass were studied during grain filling. MMF equation was used to describe the dynamics of PA accumulation. The results show that the pattern of PA accumulation was basically similar for three barley cultivars, and could be described as an ＂S-curve＂. The rate of PA accumulation was fitted to a ＂single-peak curve＂, with the maximum value occurring at around 13-14 d after anthesis. CAW453, a naked variety, had the larger accumulation rate and the shorter accumulation time in comparison with those of the two hulled genotypes, 03-34 and 06-08. The positive correlation was found between PA content and grain mass during grain filling. However, there was no significant correlation between dynamics of PA accumulation and protein, total phosphorus accumulation in barley grains. Moreover, no significant correlation was found between the rates of PA synthesis and protein, total phosphorus accumulation. The results above suggest that PA and P accumulation is independent each other during grain filling and there exists a specific pathway of P metabolism, which is probably more active than PA synthesis and accumulation.