Energy allocation to seed production of Poa annua L. populations derived from a putting green and an orchard

Abstract

In order to clarify the mechanism of the adaptability of Poa annua L. to putting greens where mowing stress are imposed remarkably with frequent and very low clipping, two populations of the weed derived from a putting green (PG) and an orchard (OR) were compared in terms of energy allocation to seed production. The results obtained from the present study were summarized as follows. When energy allocation to seed production were estimated as NSD [ (total number of seed/plant) / (dry weight of shoot) ] and WSD [ (total weight of seed/plant) / (dry weight of shoot) ], both NSD and WSD values of PG exceeded those of OR at 30 days after heading. However, no significant difference in NSD and WSD between PG and OR were observed at 60 days after heading, and contrary to above results, PG exceeded OR in NSD and WSD at 90 days after heading. These results indicate that although PG is slightly below to OR in the energy allocation at relatively early periods after heading, PG exceeds OR at late periods after heading; showing that an adaptability of Poa annua L. to a putting green partly depends on a high energy allocation to seed production.