ARS | Publication request: Composition, vigor, and proteome of mature soybean seeds developed under high temperature

Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 20, 2008
Publication Date: N/A

Interpretive Summary: Prolonged high temperatures during soybean seed development can impact seed quality. High temperatures occur frequently during soybean seed development and maturity, especially in the Southern USA, and have been reported to have a considerable effect on soybean yields, seed composition and seed vigor. The effects of a high temperature (37/30ºC) treatment on the proteome were investigated using developing (R5-days 1 and 4, and R7-days 1 and 4) and mature seeds harvested from plants grown in environment-controlled chambers. High temperature treatment decreased seed quality resulting in a greater proportion of abnormal seeds and reduced seed germination. No significant change in total seed protein concentration was detected when seed developed under high temperature conditions. Comparisons of developing and mature embryos treated with high temperature, versus the control, detected changes among proteins having important functions in plant growth and development. This information will be important to soybean researchers in their attempts to understand the effects of environmental stresses on crop performance and other plant scientists who will try to design more tolerant crop plants using classical breeding or biotechnology.

Technical Abstract: Prolonged high temperatures during soybean (Glycine max [L.] Merr.) seed development can impact seed quality. The effects of a high temperature treatment on seed composition, quality and proteome were investigated using seeds harvested from plants grown in environment-controlled chambers. After being treated with high day and night temperatures (37/30ºC) from stages R5 through R8, the total fatty acid concentration increased in mature dry seeds, while the ratio of palmitic (16:0), stearic (18:0) and oleic (18:1) acids increased, and the ratio of linoleic (18:2) and linolenic (18:3) acids decreased. Sugar also decreased, but total protein and phytic acid concentration changes were not significant. The high temperature treatment decreased seed quality resulting in a greater proportion of abnormal seeds and reduced seed germination. Proteomic analysis detected 20 protein spots whose accumulations in mature dry seeds were changed by the high temperature treatment. Among them 14 spots were identified as seven subunits of seed storage proteins and the remaining six proteins were identified as those responding to abiotic stresses or having a function in respiration: i) sucrose binding protein (SBP), ii) Class III acidic endochitinase, iii) heat shock protein (HSP22), iv) late embryo abundant protein (EM), v) Bowman-Birk proteinase inhibitor, and vi) formate dehydrogenase (FDH).