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NW Washington | John Baker did considerable research on how to best get seeds to germinate in less than good conditions while he was a professor at Massey University in NZ. From this came first his "inverted T" hoe type opener that was used mainly for seeding pastures. Baker claims that he gets better seed germination in the open inverted T slot that when using regular disc or hoe type openers. The Cross Slot is basically a disc version of his inverted T. When one of these drills goes through soil it tends to lift the soil around the opener and then press it back down. And the seed in only down about 1.5" anyway.
Also, a USDA researcher has cast some doubt on the importance of seed soil contact and germination which seems to back up Bakers earlier findings.
Here is the abstract of Stewart Wuest's paper on the subject.
GERMINATION
Vapor Transport vs. Seed–Soil Contact in Wheat Germination
Stewart B. Wuesta, Stephen L. Albrechta and Katherine W. Skirvina
a USDA-ARS, Columbia Plateau Conservation Res. Ctr., P.O. Box 370, Pendleton, OR 97801 USA
[email protected]
The assumption that seed–soil contact is important for germination of seeds has influenced imbibition research and equipment design but has not been tested. This study compared germination with and without seed–soil contact. Over a temperature range from 3 to 28°C, wheat (Triticum aestivum L.) seed was either provided with good seed–soil contact or separated from soil by fiberglass cloth. The germination system was sealed to prevent evaporation. At soil water potentials of -4.5 and -2.3 MPa, no seeds germinated in either treatment. When the soil water potential was -1.1 to -0.15 MPa, the average increase in germination time due to the absence of seed–soil contact was 0.3 d (5.6%). Days to germination ranged from 1.1 d at -0.15 MPa and 28°C, to 18.3 d at -1.1 MPa and 3°C. These results show that vapor transport may be the most important mechanism for imbibition and that liquid transport through seed–soil contact may make little contribution. Recognition of vapor transport as a sufficient, and perhaps dominant, mechanism for water transport between seed and soil should improve modeling efforts and planting equipment designs.
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225 Bushel Wheat
