|Zhang, Lingxiao -|
Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: September 25, 2009
Publication Date: N/A
Technical Abstract: Soybean seed produced from the Early Soybean Production System (ESPS) in the Midsouth often has low germination with poor seed quality. The mechanism of this phenomenon is not clear. A field study was conducted in 2008 and 2009 on a silt-loam -soil at the Delta Research and Extension Center, Stoneville MS, to investigate the role of certain fatty acids in seed quality and germination ability. Two maturity group (MG) IV soybean varieties, AG4403 (relative maturity, RM is 4.4) and AG4903 (RM 4.9), were planted in late April and mid-May. Plants matured from late August to late September. Seeds were harvested at three (3) and six (6) weeks after maturity (WAM), respectively. Preliminary results from 2008 indicated that soybean yield was reduced with delayed harvest (at 6 WAM); however, seed germination was not significantly affected. Planting dates ( seed maturity dates) affected soybean seed compositions and germination. Regression analysis indicated a significant positive correlation between seed germination and concentration of seed linoleic acid in two tested cultivars (R2 = 0.72, P<0.05). Early maturity variety AG4403 planted early had the lowest linoleic acid content while late maturity variety AG4903 planted late had the highest linoleic acid concentration. Concentration of oleic acid in the seeds had an opposite pattern compared with that of linoleic acid. Results from this study indicated that the concentration level of certain seed composition constituents such as linoleic and oleic acids in seed may be involved in the germination ability of soybean seeds. The temperature, especially at seed maturity period, may be an essential factor in altering the concentration of the fatty acid (s), which further determines the seed germination ability.