Type of Document Dissertation Author Detoni, Cezar Ernesto Author's Email Address email@example.com URN etd-63197-21517 Title Grain Sorghum Field Emergence and Seed Vigor Tests Degree PhD Department Crop and Soil Environmental Sciences Advisory Committee
Advisor Name Title Brann, Daniel E. Welbaum, Gregory E. Wolf, Dale D. Abaye, Azenegashe Ozzie Committee Chair Parrish, David J. Committee Co-Chair Keywords
- seed tests
- heat shock
- electrical conductivity
Date of Defense 1997-06-30 Availability unrestricted AbstractPoor emergence of sorghum [(Sorghum bicolor (L) Moench] affects the stand and
potential yields. The major objective of this research was to find correlations
among field emergence data and laboratory seed vigor tests. Thirty-two and 30
hybrids of sorghum were planted at three Virginia locations in 1995 and 1996,
respectively. Field emergence was subsequently compared with results from
laboratory tests that included: 1) standard germination; 2) osmotic-stress using
polyethylene glycol 8000 (mw); 3) heat-shock using 2 hr at 50?C stress; 4)
electrical conductivity of steep water of germinating seeds; and 5) seed mass.
Field emergence of grain sorghum differed among hybrids, years and locations.
Mean emergence across years and locations was 67.5%, whereas mean
germination in the laboratory was 87.8%. There were interaction between hybrid
and location and between hybrid and year. Germination under optimal conditions
(standard germination test) and with osmotic or heat-shock stress differed among
hybrids. Regression analyses showed a weak correlation between laboratory
germination (with or without stress) and field emergence in both years. The fresh
weight of seedlings whether from standard germination or stress tests also
differed among hybrids in both years, and the associations with field emergence
were weakly correlated in 1996. Hybrids showed significant differences in radicle
length when grown under laboratory stress in both years following standard
germination. There was a weak correlation with field emergence and radicle
length following heat-shock treatment in 1996. The measurement of electrical
conductivity in the seed steep water showed significant differences among
hybrids. A weak correlation with field emergence was seen in 1996.
Conductivity values per gram of seed and per cm2 of seed area revealed
differences among hybrids. The correlation of these parameters with field
emergence was higher than conductivity per seed. Seed mass varied among
hybrids in both years , but was no correlation between seed mass and emergence.
Of the laboratory parameters examined, germination proved to be the most
consistent predictor of variations in field emergence of sorghum hybrids.
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28.8 Modem 56K Modem ISDN (64 Kb) ISDN (128 Kb) Higher-speed Access ABSTRACT.PDF 79.51 Kb 00:00:22 00:00:11 00:00:09 00:00:04 < 00:00:01 APPEND.PDF 50.53 Kb 00:00:14 00:00:07 00:00:06 00:00:03 < 00:00:01 CHAP1.PDF 59.62 Kb 00:00:16 00:00:08 00:00:07 00:00:03 < 00:00:01 CHAP2.PDF 58.92 Kb 00:00:16 00:00:08 00:00:07 00:00:03 < 00:00:01 CHAP3.PDF 96.44 Kb 00:00:26 00:00:13 00:00:12 00:00:06 < 00:00:01 CHAP4.PDF 97.60 Kb 00:00:27 00:00:13 00:00:12 00:00:06 < 00:00:01 CHAP5.PDF 104.84 Kb 00:00:29 00:00:14 00:00:13 00:00:06 < 00:00:01 CHAP6.PDF 94.37 Kb 00:00:26 00:00:13 00:00:11 00:00:05 < 00:00:01 CHAP7.PDF 87.29 Kb 00:00:24 00:00:12 00:00:10 00:00:05 < 00:00:01 CHAP8.PDF 30.42 Kb 00:00:08 00:00:04 00:00:03 00:00:01 < 00:00:01 CHAP9.PDF 63.55 Kb 00:00:17 00:00:09 00:00:07 00:00:03 < 00:00:01 TIT.PDF 30.02 Kb 00:00:08 00:00:04 00:00:03 00:00:01 < 00:00:01 VITA.PDF 2.74 Kb < 00:00:01 < 00:00:01 < 00:00:01 < 00:00:01 < 00:00:01
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