Evaluation of Flax and Other Cool-Season Oilseed Crops for Yield and Adaptation in Texas

Finding the alternate biofuel feedstock(s) in addition to and/or replacement of traditional soybean feedstock is necessary to meet the future demand of biofuels. Two field studies were conducted in diverse environments in Texas during 2007-2011 to evaluate the yield, adaptation, and oil content of 4 cool-season crop species (rapeseed, safflower, flax, and camelina). In addition to the evaluation of yield and adaptation in these cool-season crops, two more studies were conducted during 2009-2011 to study flax yield components (field study) and the effect of vernalization and photoperiod on flowering of flax (growth chamber study). Out of two field studies conducted in Texas, the evaluation of four cool-season crops was designed as a randomized complete block with fifty-one genotypes (four species) and three replications in nine locations across the Texas. In addition to the evaluation of cool-season crops, an exclusive replicated study was conducted in flax to evaluate 20 genotypes for the yield, adaptation, and association between yield and its components in three locations in South Texas. Additionally, a growth chamber study was setup as a split-split plot design with twenty genotypes, two vernalized treatments (vernalized and unvernalized), and two photoperiods (10 hours and 14 hours). Spring rapeseed (canola) and safflower were the highest yielding crops with a maximum yield of 1372 kg ha-1 and 1240 kg ha-1, respectively. In South and Central Texas, fall - seeded flax yield averaged 1075 kg ha^-1 with a mean oil content of 38.3%. The flax genotype evaluation in Southeast Texas suggested that all genotypes developed in Texas showed relative cold tolerance compared to genotypes developed in other locations. A cross between Caldwell / Dillman (Texas genotype) was highly adapted to the environments of southeast Texas. Nekoma and York (genotypes developed in North Dakota) yielded well in non-cold years (> -2 degrees C) in College Station. Overall, flax is well adapted to growth in the area surrounding College Station, TX. The results of association of yield and its components in flax suggest that tiller number was the most significant contributing factor (p