植物不同组织部位的植硅体形态、组合研究有助于准确鉴定考古地层植硅体来源植物的具体种类以及组织部位;生长周期内植硅体形态、组合变化研究有利于探讨植硅体的形成机制,认识植硅体形态组合变化与环境因子之间的关系,科学解释土壤及沉积物植硅体古植被、古环境信息。玉米变种亚航0919在生长的初期,尤其是前3片真叶,含比重较高的3片以上的多铃型植硅体;随着玉米生长天数增加及生长温度的升高,第4—5片真叶3片以上多铃型植硅体消失,哑铃型植硅体含量逐渐增加,尖型及棒型植硅体含量有所降低,叶片哑铃型植硅体长度(L)及宽度(W)有增加的趋势;相同生长阶段,叶片与叶脉植硅体组合及大小显著不同,叶脉相对叶片含较低比重的哑铃型植硅体、较高比重的十字型和椭圆-哑铃型植硅体,叶脉中哑铃型植硅体小于叶片中的。玉米叶片植硅体形态、组合在生长季节内的变化主要与植物的成熟阶段及生长环境温度的变化有关,其植硅体形态、大小和组合,尤其是哑铃型植硅体大小能够响应温度变化。
Studies on the morphology and assemblage variation of phytolith from tissue to tissue and within specific tissues help us refine species identifications from prehistoric strata and define specific tissues from which the phytoliths came. The investigations on phytolith morphology and assemblage variation within plant during growing season can help to understand phytolith formation mechanism, the relationships between phytolith assemblages and environmental factors which can explain the palaeoenvironment and palaeovegetation information of phytolith in soils and sediments. The larger proportions of polylobates, which are bilobates with one or more links in the shaft, were produced in leaves, especially the first three new born real leaves of maize variety (Yahang 0919) in early growing stage. The ploybilobates with more than 3 lobes disappeared, bilobates phytolith content decreased, hair cell and elongate phyto- liths increased, and the size of length (L) and width (W) of bilobates phytolith got larger and larger in the fourth and fifth real leaves as the plant grown under the increasing continuously air temperature. At the same growth stages, the shape, size and assemblage differ between silica bodies of leaves and those of main veins. Midrib cells produce a lower proportion and smaller size of bilobate, higher proportion of cross and elliptoid/bilobodi forms compared to leaves. The variation of phytolith morphology, size and assemblage in maize leaves were influenced by the stage of plant maturity and its growing environmental conditions. The leaf phytolith types, sizes and assemblages, especially bilobate sizes can respond to the temperature changes.