| Abstrakt: |
The lack of published reports on the effects of chemicals and light on germination of dormant indiangrass (Sorghastrum nutans(L.) Nash) seed prompted this study. Cleaned hand‐harvested spikelets were planted between layers of germination toweling in covered plastic boxes, or on top of or between several layers of filter paper in plastic petri dishes. Each germination test consisted of 4 replicates of 100 spikelets, with or without moist prechilling at 4‐6 C for 2 or 4 weeks, held for 7 to 15 days at alternating temperatures of 18–22 C (night) and 25–28 C (day), with or without light. Some tests received red light. In other tests, various concentrations of gibberellic acid were used as the moistening agent; in others, seeds were presoaked in sodium hypochlorite or sulfuric acid. Spikelets stored dry at room temperature (18–28 C) remained dormant for 7 months before dormancy began to decline. Pregermination moist chilling for 4 weeks usually resulted in near maximum germination. Light was required for maximum germination of seed chilled for 2 weeks. Red light was more effective than daylight when exposure time was 2 hours or less. Generally, spikelets failed to respond to light once they had failed to germinate in the dark. Soaking spikelets in sodium hypo‐chlorite solution increased germination only in the presence of light. Sulfuric acid and gibberelic acid treatments increased germination in the dark, but higher germinations were obtained in the presence of daylight. |
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