Germination biology of Hibiscus tridactylites in Australia and the implications for weed management.

Bhagirath Singh Chauhan

doi:10.1038/srep26006

Abstract

Hibiscus tridactylites is a problematic broadleaf weed in many crops in Australia; however, very limited information is available on seed germination biology of Australian populations. Experiments were conducted to evaluate the effect of environmental factors on germination and emergence of H. tridactylites. Germination was stimulated by seed scarification, suggesting the inhibition of germination in this species is mainly due to the hard seed coat. Germination was not affected by light conditions, suggesting that seeds of this species are not photoblastic. Germination was higher at alternating day/night temperatures of 30/20 °C (74%) and 35/25 °C (69%) than at 25/15 °C (63%). Moderate salinity and water stress did not inhibit germination of H. tridactylites. Seedling emergence of H. tridactylites was highest (57%) for the seeds buried at a 2 cm depth in the soil; 18% of seedlings emerged from seeds buried at 8 cm but no seedlings emerged below this depth. Soil inversion by tillage to bury weed seeds below their maximum depth of emergence could serve an important tool for managing H. tridactylites.

Highlights

Be useful, the germination requirements of H. tridactylites in Australia may be different from those of H. trionum in Greece
It was hypothesized that: a) the germination percentage of H. tridactylites seeds will increase with scarification, b) the germination percentage of H. tridactylites seeds will decrease linearly with increasing salt and water stress, and c) the percent emergence of H. tridactylites seedlings will decrease linearly with increasing seed burial depth in soil
Scarification stimulated germination of H. tridactylites, indicating that the hard seed coat is the primary reason for the inhibition of germination

Summary

Introduction

Be useful, the germination requirements of H. tridactylites in Australia may be different from those of H. trionum in Greece. A study was conducted to determine the effects of scarification, temperature and light, salt and osmotic stress, and burial depth on seed germination and seedling emergence of H. tridactylites. It was hypothesized that: a) the germination percentage of H. tridactylites seeds will increase with scarification, b) the germination percentage of H. tridactylites seeds will decrease linearly with increasing salt and water stress, and c) the percent emergence of H. tridactylites seedlings will decrease linearly with increasing seed burial depth in soil

Methods

Results

Conclusion