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Full-Text Articles in Life Sciences
Influence Of Cultural Practices On The Sunflower Seed Weevil In South Dakota, Joe V. Gednalske
Influence Of Cultural Practices On The Sunflower Seed Weevil In South Dakota, Joe V. Gednalske
Electronic Theses and Dissertations
The purpose of this study was to evaluate cultural methods for sunflower seed weevil control. Procedures examined included the influences of tillage methods, crop rotation, date of planting, hybrid maturity, and degree-day units in emerging seed weevil populations. Tillage practices done as both fall and spring treatments including discing, chisel plowing, nobel blading, and moldboard plowing were examined for their effect on larval position in the soil, time of adult weevil emergence, and the number of adults emerging from the soil. Crop rotations were investigated for possible influence on weevil mortality and time of adult emergence. Sunflower planting date and …
Effects And Interactions Of Nitrogen And Soil Moisture Status Under A High Yield Irrigated Corn Environment, Dwayne L. Beck
Effects And Interactions Of Nitrogen And Soil Moisture Status Under A High Yield Irrigated Corn Environment, Dwayne L. Beck
Electronic Theses and Dissertations
A two-part study was conducted during the 1979 and 1980 growing seasons on irrigated lands adjoining the Missouri River in central South Dakota. Empirical [sic] models were developed to describe the response of irrigated corn (Zea mays L.) to soil water status and nitrogen fertilization at a location recently developed for sprinkler irrigation. Nitrogen fertilizer rates of 0, 100, 200, and 400 kg of N/ha were used under water treatments consisting of a 2.5 cm irrigation when soil water matric potential at a depth of 40 cm decreased to -35, -50, and -75 kPa. Yield differences due to soil water …