Objectives
1. Compare the seed and fiber yielding ability of fourteen fiber flax varieties and two oilseed varieties at a location near Saskatoon in the year 2000;
2. Produce a larger quantity of fiber flax seed that can be used in more extensive agronomic and variety comparison trials in 2001 and thereafter, and
3. Compare the fiber content and strength of the retied straw produced by each variety at maturity.
Project Description
To generate these results, two plot experiments, each with four replicates, were set up near Saskatoon in May 2000 to produce seed and fiber. The variety trial consisted of fourteen fiber varieties and two oilseed varieties planted on May 23’d using a seeding rate of 65 kg/ha in plots with dimensions of 12 feet by 70 feet. The seeding rate trial used two fiber varieties planted on May 24th at seeding rates of 40 kg/ha, 80 kg/ha and 120 kg/ha in plots with dimensions of 3 feet by 20 feet. Plots were sprayed for weeds at the appropriate time, but a late flush of weeds reduced seed and straw yields, even though the plots were sprayed a second time. In October 2000, when the seed was ripe, a plot harvester was used to cut the seed bolls off the stems as high as possible from the ground to maximize the height of the remaining stubble. The resultant seed was cleaned and used to calculate the seed yield of each plot. It is now being stored at Biolin Research Inc. for use in further agronomic trials.
After the seed harvest was complete, one-meter square samples from the stubble remaining in the plots were pulled out of the ground, wrapped, labeled and stored. Sub-samples of each straw sample were prepared and retted by staff of Biolin. A reciprocating blade-type breaker/decorticator was used to roughly separate clean bast fibers from the retied dry straw and final cleaning of the bast fibers was done by hand. Un retied subsamples were also cut at ground level and at three inches above ground level to generate data that could be used to calculate straw yields per hectare under several different straw harvest scenarios. Sub-samples of retted straw from each plot were conditioned in a closed chamber for 24 hours at 60% relative humidity and 21 degrees Celsius. Two bundles of fiber approximately 20 mg. in weight were then taken from each sub-sample and tested for strength using a set of custom-made pins and “Quick-Clamps” on an lnstron machine.
Variety Trial
In the case of the variety trial, the results showed that the average plot seed yield of fiber varieties ranged from 1.8 bus/ac to 5.6 bus/ac. However, only Opaline had an average plot seed yield that was significantly lower than the other tested fiber varieties and only Viking had an average yield that was significantly higher than the other tested fiber varieties. The average plot seed yield from the oilseed varieties was significantly higher than for the tested fiber varieties with Flanders yielding 9.6 bus/ac and Valour yielding 12.2 bus/ac.
The bast fiber content, expressed as a percent of unretted straw weight, varied from 27.6 to 36.4 percent in the fiber varieties. Hermes, Ilona, Escalina and Diva had fiber contents that were significantly higher than other tested varieties. Only the two oilseed varieties, Flanders and Valour, had fiber contents that were significantly lower than the other tested varieties, at 23.4% and 19.6%, respectively.
The length of salvaged straw was assumed to be all the stubble remaining three inches above the ground that was not cut off by the plot combine when it was cutting the seed bolls off. In general, the combine operator can cut taller varieties at a greater height than shorter varieties, however, if a variety has uneven heights or bolls that are positioned lower down on short tillers, the operator would have to cut the stubble low even, if it were a tall variety. The salvaged height of plots ranged from 30.4 to 43.9 cm with no variety being significantly taller than average, but Valour, Flanders and Viking were significantly shorter than the other tested varieties.
The yield of bast fiber yield per hectare was estimated by multiplying the percent of bast fiber in unretted stems by the weight of unretted salvaged straw. This calculation gave bast fiber yields that varied from 247 to 886 kg/ha with Hermes, Ilona and Escalina having significantly higher bast fiber yield per hectare and Valour and Flanders having significantly lower bast fiber yield. Seed and straw yields were both negatively impacted by the late flush of weeds that came up after the initial spraying of weeds had been completed.
Although the fiber of some varieties appeared to be stronger than others, there was no statistically valid difference in fiber strength between any of the varieties. This may have been due to the fact that all varieties were fully mature when the straw samples were collected and hence do, in fact, have roughly the same fiber strength when fully mature. It could also be because there are small differences in fiber strength, but these cannot be detected using statistical tests unless a large number (e.g., >20) of fiber bundles were tested from each sub-sample.
Seeding Rate Trial
In the case of the two fiber varieties planted at three different seeding rates, the results showed individual plots ranged from 6.6 bus/ac to 19.2 bus/ac. Seed yields at 40 kg/ha were significantly higher than seed yields at 80 or 120 kg/ha. The bast fiber percent was not significantly different between the three seeding rates but the variety, Hermes, had significantly higher fiber content than the variety, Evelin. Straw length was not significantly different between the two varieties but the 40 kg/ha seeding rate produced straw that was significantly longer (about 12%) than the other two seeding rates. The salvageable straw yield was significantly lower for the 40 kg/ha seeding rate but there was no significant difference between the 80 and 120 kg seeding rates. Hermes did not produce significantly more salvageable straw per hectare, but it did produce significantly more bast fiber per hectare. Since straw length and salvageable straw yield were approximately the same between Hermes and Evelin, the higher yield of bast fiber per hectare from Hermes must be due entirely to its higher fiber content relative to Evelin.
There was no statistically significant difference in fiber strength between Evelin and Hermes. Fiber from the 80 kg/ha seeding rate appeared to be slightly stronger than from the other two seeding rates but it was not a statistically significant difference.
The reader should keep in mind that seeding was done in narrow rows, and this could have easily masked the potential benefits of heavier seeding rates. In addition, resources were not available to compare all the possible fiber characteristics (e.g., fineness, percentage of long line); some of which could be significantly affected by seeding rates.
