Premium
Germination under Controlled Temperature and Field Emergence of 13 Sorghum Cultivars
Author(s) -
Brar G. S.,
Stewart B. A.
Publication year - 1994
Publication title -
crop science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.76
H-Index - 147
eISSN - 1435-0653
pISSN - 0011-183X
DOI - 10.2135/cropsci1994.0011183x003400050036x
Subject(s) - germination , sorghum , cultivar , biology , horticulture , agronomy , sorghum bicolor
Temperature and cultivar strongly influence the establishment of dryland sorghum [ Sorghum bicolor (L) Moench]. Little is known about the extent of variability in germination and emergence among different sorghum cultivars as affected by temperature. Our objective was to monitor cultivars for germination under different temperature regimes in the laboratory, and subsequently to test their performance in the field for emergence. Sorghum seeds were screened for germination during 10 d in polyethylene growth pouches held in the dark at constant temperatures of 10, 15.5, 21, 26.5, 32, or 37.5°C. In the field study, 13 hybrids were planted on 4, 13, 21, and 26 June 1991, and observed for emergence. Germination percentage significantly ( P < 0.05) increased as temperature of treatment increased from 15.5 to 26.5 or 32°C when averaged across the cultivars, with no germination at 10°C. As temperature increased from 15.5 to 37.5°C the average time to germination decreased significantly ( P < 0.05). Cultivar Richardson‐9112 had the greatest germination percentage (98%) and DK‐46, well as DK‐42, had the least (79%) when averaged across the five temperatures. For 80% or above of the seeds to germinate, it required 7 d at 15.5, 3 d at 21, 2 d at 26.5 and 32, and 1 d at 37.5°C temperature. An optimum temperature of the cultivars investigated varied between 26.5 and 32°C. Mean field emergence was significantly ( P < 0.05) greatest (83%) with Richardson‐9112 and least (36%) with DK‐42Y as well as DK‐46 compared to nine cultivars. Relative mean emergence in the field regressed with relative mean germination in the laboratory yielded a significant ( P < 0.05) correlation r 2 = 0.77). This study demonstrates the cultivar differences for response to temperature and information concerning variability in germination, and emergence.