Grain Sorghum Field Emergence and Seed Vigor Tests

Grain Sorghum Field Emergence and Seed Vigor Tests
Author: C.E. Detoni
Publisher:
Total Pages: 129
Release: 1997
Genre:
ISBN:

Poor 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 50o.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 loction 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 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.

Effect of Seed Vigor Upon Field Performance and Yield of Grain Sorghum (Sorghum Bicolor (L.) Moench)

Effect of Seed Vigor Upon Field Performance and Yield of Grain Sorghum (Sorghum Bicolor (L.) Moench)
Author: Cilas P. Camargo
Publisher:
Total Pages: 150
Release: 1971
Genre: Sorghum
ISBN:

Hybrid grain sorghum seeds were aged artifically for 0, 3, 5, 7, and 11 days at 42oC and 100% RH, wich produced high, medium, low and lowest vigor level. Among the various laboratory tests performed, standard germination and field mergence, were the least sensitive in discerning the physiological condition of the seed lots. The speed of germination more accurately differentiated the degree of deterioration of the seed lots and was closety correlated to yield. Adverse effect of planting low vigor seeds was found to be related to plant height, panicle exsertion, anthesis, tillering capacity, length of the panicle, and yield. Less vigours seeds produced plants which were not able to "catch up" to the vigorous ones. These slow growing plants were significantly inferior in panicle exsertion to those produced from more vigorous seeds. Seeds aged for 7 and 11 days had their process of exsertion delayed for about 2 and 3 days, respectively. Anthesis, conseguently, was also significantly retarded. Tillering capacity of plants produced from low vigor seeds was significantly reduced, as well as grain yield. Primary head yield was also significantly reduced about 14% for the more deteriorated seeds, and 12% for the mixed treatment, as compared to the control. Yield reductions of 9, 4, and 3% were also detected in seeds aged for 7, 5, and 3 days, respectively, as compared to the check. Seed moisture content generally increases as the vigor level decreased, indicating that the process of maturation was delayed as a (...).

Relation of Seed Size and Specific Gravity to Germination and Emergence in Sorghum (Sorghum Bicolor (L.) Moench).

Relation of Seed Size and Specific Gravity to Germination and Emergence in Sorghum (Sorghum Bicolor (L.) Moench).
Author: A. L. Alvim
Publisher:
Total Pages: 51
Release: 1975
Genre:
ISBN:

Two seed characteristics of grain and forage sorghum were studied to determine the extent to which they were associated with viability and vigor. These characteristics were seed size and specific gravity. Fifty seed were obtained from the Mississippi State Seed Testing Laboratory. Twenty-five lots were separated into three size classes designated as large, medium, and small. The other twenty-five lots were separated into three specific gravity cclasses and designated as light, medium, and heavy. The physiological quality of seed from various seed sizes and specific gravity classes of each lot was evaluated for vaibility by the standar germination test and for vigor by the accelerate aging technique and filed emergence response. There was no consistent relationhip between seed size and viability of processed lots of seed. Each seed lot reacted differently, and there was considerable variations among the lots. Specific gravity seemed to be more consistently related to viability in processed lots than was seed size. In general, in each seed lot, an increase in specific gravity of the seed was accompanied by an increase in germination. Accelerated aging technique as a test for seed (capacity to germinate and emerge after being stressed) revelated that seed of the small size and those of light weight were more inferior after accelerated aging than the other size ans weight classes. In general, large, heavy seed gave better responses than did small, light seed. In the field emergence experiment, the relationships (...).