Analysis of factors regulating growth phase of individual tillers in rice, barley and wheat

众所周知，植物生长阶段从营养生长阶段向生殖生长阶段的转变主要取决于其生长时期的日照长度和温度。近年来，同一株植物的分蘖发育幼穗的时间明显不同。在叶片出芽和抽穗日期的调查中，得到如下结果：1。单株分蘖上的叶片按“片山”同步叶片生长理论的规则顺序展开。初生分蘖比主茎多一片叶，次生分蘖也比初生分蘖多一片叶。从主茎第6 ~ 8节开始的初生分蘖，叶片展开间隔短，抽穗早。初生分蘖从主茎下节萌发的时间比6 ~ 8分蘖晚。由于在直接播种植株上观察到这一现象，认为上述趋势可能是水稻植株的固有特性。在主茎上每一个偶数节的初生分蘖膨大结束时切掉叶片，偶数初生分蘖抽穗晚。而叶片完整的奇数初生分蘖对抽穗率无显著影响。用注射器将赤霉素注入主茎叶静脉，使处理过的叶片节间伸长。然而，他们的舵柄根本没有回应。这表明同一株植物上的单个分蘖在生长方面是独立的。在大麦和小麦中，随着分蘖节点位置的上升，初蘖抽穗数据有所延迟。

It is well known that conversion of growth phase, from vegetative growth to reproductive one, is mainly dependent on day length and temperature in their growing period. Recently, it is clear that the same plant has a different time to develop young panicle in their individual tillers. In an investigation of leaf emergence and heading date, results obtained were as follows :1.Leaves on individual tillers expanded in regular sequence of synchronous leaf growth theory by 'Katayama'. Primary tillers had one more leaf than that of main stem, and secondary tillers had also one more leaf than that of primary tillers.2.Primary tillers which originated from 6 - 8th node on main stem showed short intervals of their leaves expansion and earlier heading.3.Primary tillers emerged from lower node on main stem headed later than that of 6 - 8th tillers. As this was observed in direct seeding plant, it is considered that above tendency may be inherent properties in rice plants.4.When the leaves of primary tillers from every even numbered nodes on main stem were cut at the end of their expansion, even numbered primary tillers showed late heading. Whereas, odd numbered primary tillers which had intact leaves, did not show any influence in heading.5.Gibberellic acid, injected by syringe to the vein of main stem leaf, elongated upper internode of treated leaf. While, their tillers did not respond at all. These suggests that individual tillers on a plant were independent as to their growth.6.In barley and wheat, heading data of primary tillers delayd as the node position of primary tillers proceed upwards.