Journal of Stress Physiology &
Biochemistry, Vol. 9 No. 4
2013, pp. 85-100 ISSN 1997-0838
Original Text Copyright (cc) 2013 by Barakat, Kabeil, Hegazy, Singer
ORIGINAL ARTICLE
Data source : Google Scholar
QueryDate : 2016-12-24
Cites : 1
Synergetic action of light and
temperature on seed germination of some solanaceae members
Nasser A.M. Barakat 1*,
H.F. Kabeil2, A.K. Hegazy2 and Nesrine S. Singer1
1 Botany and microbiology
department, Faculty of science, Minia University, 61519. Egypt. 2 Botany and microbiology department, Faculty of science,
Cairo University, Giza 12613, Egypt.
The objective of
the present study was to
evaluate the effects of nine
combinations of temperature and light on
seeds germination of four solanaceae
species (Datura innoxia,
Hyoscyamus muticus, Solanum nigrum and Withania somnifera) in
germination chamber. The influence of combined of three alternative
temperature regimes from 10 to 40 °C, with 10°C intervals, under three
light levels (the continuous white light, alternative and darkness)
were tested. The germination parameters as germination percentage, seed
vigor index, dormancy, germination speed and
germination index, and were measured
and calculated. The data reveled some similarities in
germination percentage and seedling vigor index among Datura innoxia, Solanum nigrum in
one hand and between Hyscyamus muticus and Withinia sommenefreae on the other
hand, while germination speed and germination index showed some
similarities between Datura
innoxia, Withinia sommenefreae
and between Hyscyamus muticus
and Solanum nigrum. The
optimum condition for the germination of the seeds was varied
with species (species-dependent): some
species Hyoscyamus
muticus and Withinia
sommenefreae germinate easier under combined effects of light
and temperature, whereas, Solanum
nigrum and Datura innoxia
decreased their germination in darkness conditions. The maximal
germination was reached in Hyoscyamus
muticus follwed by Withania
somnifera, Solanum nigrum
and Datura innoxia species
under wide range of selected combinations. With the
exception of Datura
innoxia all other species seemed
a photoplastic character. No relationship
was found between germination percentage
and alternating temperature especially in Hyoscyamus muticus and Withania somnifera. Alternating
temperature is not the main factor affecting
germination percentage. We concluded that
the regime of light suppressed the
effects alternating temperatures on seed
germination of Datura
innoxia species. It was concluded that
synergized effects of light and
alternating temperatures, enhanced seed germination of Hyoscyamus mutucs and Solanum nigrum. Thus, the light
regime can play a vital role in present and future weed management
strategies.
Key
words: germination ecology, solanaceae,
combined alternate temperature and light,
seeds, Germination index, vigor, Dormancy
