Evaluation of various solvent systems for lipid extraction of wheat Triticum aestivum L. cv. Rideau seeds showed that boiling 2-propanol followed by the Bligh-Dyer procedure was the most efficient method, with respect to lipid yield and ability to inactivate lipolytic enzymes. Ten phospholipids were identified in dry seeds; the major components being phosphatidyleholine, lysophosphatidylcholine, N-acyl lysophosphatidylethanolamine, N-acylphosphatidylethanolamine, and phosphatidylethanolamine. After growth for 1 week (2 C) or 31 hours (24 C), the proportions of phosphatidylethanolamine + lysophosphatidic acid and phosphatidic acid increased, lysophosphatidylcholine decreased, and the remaining phospholipids showed little change. At 5 weeks (2 C) or 72 hours (24 C), the seedlings showed 5-fold increases in the proportion of phosphatidic acid largely at the expense of phosphatidylcholine, small decreases in N-acyl lysophosphatidylethanolamine and N-acylphosphatidylethanolamine, and significant increases in lysophosphatidylcholine. The changes in phosphatidic acid and phosphatidylcholine are interpreted as being partially due to increasing phospholipase D activity during germination. In general, the phospholipid composition was similar in morphologically equivalent seedlings grown at 2 C or 24 C. The increased membrane content in seedlings grown at 2 C does not reflect any preferential synthesis of individual phospholipids.In a previous study (8) seedlings of Triticum aestivum L. cv.Rideau grown at 2 C were found to be more resistant to freezing temperature than their morphological equivalents germinated at 24 C. This resistance was correlated with increased synthesis and unsaturation of cell membrane phospholipids at the lower temperature. Knowledge of the changes in amounts of individual phospholipids in wheat seedlings during germination at both temperatures is required to clarify further the biochemical mechanisms underlying cold-hardiness.The phospholipid composition of wheat seeds has not pre- III. Petroleum ether (b.p. 30-60 C); three 1-hr extractions each with 10 ml of solvent at room temperature (3).IV. Chloroform-methanol-water (1:2:0.8); by the BlighDyer procedure (8). V. Boiling 2-propanol; two extractions each with 5 ml of solvent followed by a Bligh-Dyer extraction (8) of the meal residue; the extracts were combined.VI. Chloroform-methanol (2: 1); four 1-hr extractions with 10 ml of solvent followed by gel filtration on Sephadex G-25 (29).All total lipid extracts were brought to dryness under N2, and the residues were dried in a vacuum desiccator to constant weight, dissolved in 5 ml of chloroform, and aliquots were taken for phosphorus and fatty acid analysis (8).Phospholipid Composition of Seeds. Seeds were imbibed for 5 hr at 24 C, incubated at either 24 C for 31 and 72 hr or at 2 C for 1 and 5 weeks as described elsewhere (8); 2-g lots of seeds were macerated with 0.5 g of silica gel in a mortar with pestle, and total lipids were extracted separately by the methods IV and V. An aliquot of t...

All possible crosses, excluding reciprocals, among the nine strains [Illinois high oil (IHO), reverse high oil (RHO), switchback high oil (SHO), low oil (ILO), reverse low oil (RLO), high protein (IHP), reverse high protein (RHP), low protein (ILP), and reverse low protein (RLP)] in the Illinois long term selection experiment for percent oil and protein in corn (Zea mays L.) were grown to measure their performance and to study; 1) the effects of oil and protein percentage on grain yield and other agronomic traits, 2) the effects of selection for percent protein on components of percent protein, 3) the relationship of percent oil and protein to calorie production, and 4) the importance of genetic effects for several traits.Results obtained suggest that; 1) grain yield is negatively correlated with percent oil and percent protein, 2) percent protein in the kernel is primarily determined by percent protein in the endosperm, 3) calories per g dry matter are largely determined by percent oil while calories per kernel or ha are largely determined by kernel weight or grain yield, 4) the sum of squares (s.s.) due to heterosis accounted for only 5 and 7%, respectively, of the entry s.s. for percent oil and percent protein but over 50% of the entry s.s. for yield of grain and protein, and 5) evidence was obtained of dominance for both high and low percent oil.

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or1"2-corrponent arising from thc interaction between years, locations and cultivars.

The effects of fatty acid concentration and positional specificity on maize triglyceride structure were evaluated from the stereospecific analyses of triglycerides from 12 genotypes. The fatty acids at each position were influenced by the fatty acid concentration in the total triglyceride except for the saturates in the 2 position. The fatty acid concentration had the greatest effect on the fatty acid composition of position 3. The existence of positional specificity was evident from the nonrandom distribution of the fatty acids among the three positions of the triglycerides. The concentration and positional specificity effects could be separated in selected genotypes and their crosses. This indicated different genetic controls for each effect.