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INHERITANCE OF SUBCROWN INTERNODE LENGTH IN WINTER BARLEY AND RELATED STUDIES INVOLVING WINTERHARDINESS
Abstract
The inheritance of subcrown internode length in the winter barley cross NE62203 x MO B2632 was investigated as a component for increasing winter survival. Mean subcrown internode lengths of NE62203 and MO B2632 were 0.2 and 4.3 cm, respectively. F(,2) plants segregated in a continuous distribution except for 13% which were in the 0.0 to 0.5 cm class. Heritability estimates, calculated by the variance of F(,2) plants method and parent-offspring regression of F(,3) family means on F(,2) plants, were 85.3 and 86.9%, respectively. The high heritability of this character indicates that selection for short subcrown-internode length should be effective. Results from generation means analysis showed that additive gene effects accounted for 95.0% of the total genetic variation. However, significant dominance, additive x additive epistasis, and additive x dominance epistasis were also detected. Controlled environment tests investigating a genotype x environment interaction for field winter survival in winter barley were conducted. The variety Kearney dehardened at a faster rate, and had a greater reduction in survival at high crown-moisture contents that the three Nebraska lines tested. The differential effects of crown moisture content on cold injury in the cultivars studied could explain the genotype x environment interaction for field winter survival. Production studies conducted at two Nebraska locations for 3 years demonstrated that winter barley yields obtained with no-tillage were comparable to those obtained with conventional tillage. Fourier (harmonic) analysis was performed on soil temperature data measured at two depths under no-tillage and conventional tillage and temperature prediction equations were computed. Soil temperature fluctuations were smaller and minimum temperatures were warmer with no-tillage compared to conventional tillage. This was due to a more compact soil and the presence of protective residue with no-till. Because minimum soil temperatures at the depth of crown formation with no-tillage were often significantly warmer ((GREATERTHEQ) 2.0 C) than those with conventional tillage, the practice of no-tillage should increase winter survival.
Subject Area
Agronomy
Recommended Citation
DOFING, STEPHEN MICHAEL, "INHERITANCE OF SUBCROWN INTERNODE LENGTH IN WINTER BARLEY AND RELATED STUDIES INVOLVING WINTERHARDINESS" (1983). ETD collection for University of Nebraska-Lincoln. AAI8328165.
https://digitalcommons.unl.edu/dissertations/AAI8328165