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Cook, C.G. and A.W. Scott, Jr. 1993. Utilization of methanol stress for
evaluating kenaf quality. p. 411-412. In: J. Janick and J.E. Simon (eds.),
New crops. Wiley, New York.
Utilization of Methanol Stress for Evaluating Kenaf Quality
Charles G. Cook and Andrew W. Scott, Jr.
- METHODOLOGY
- RESULTS
- DISCUSSION
- REFERENCES
- Table 1
- Table 2
Problems encountered in the establishment of uniform, vigorously growing kenaf
(Hibiscus cannabinus L.) may result from poor seed quality. Although
germination may remain relatively high, poor quality seeds often lack seedling
vigor and are more susceptible to diseases and environmental stresses. Studies
with soybeans (Mugnisjah and Nakamura 1986) and cottonseed (Hernandez 1987)
show that methanol stress mimics the effects of weathering and accelerated
aging, and may be a useful screening tool for evaluating seed quality and
seedling performance. The objective of this study was to determine whether
methanol stress could be used in the evaluation of kenaf seed to rapidly
ascertain seed quality.
Seed of five kenaf genotypes with similar seed production and weather exposure
history were immersed in 20% methanol-water solutions for four selected
durations (0, 1, 3, 5 h), and sown in the field. Genotypes included:
'Everglades 71' (E71), 'Tainung 1' (T1), 'Cuba 108' (C108), '15-2' (X15), and
'19-117-2' (X117). The study was conducted at two Texas locations, Weslaco and
Monte Alto. Experimental design was a randomized complete block, with four
replications. Single row plots were 6.7 m in length and spaced 1.0 m apart.
One hundred seed were planted with a cone planter in each plot and the number
of emerged seedlings were counted on weekly basis for six weeks. Initial
emergence and final stand establishment were determined at seven and 42 days
after planting respectively. Post-emergence damping off was determined
throughout the six week period and expressed as the percentage of dead emerged
seedlings.
No significant genotype x location or treatment x location interaction was
observed for initial emergence, final stand establishment, or post-emergence
damping-off. Therefore, results presented here were combined over the two
locations. Genotypes differed for initial emergence under the methanol
treatments (Table 1). Emergence of E71 and T1 was greater than X117 under the
control treatment. Differences also occurred among genotypes in the methanol
treatments, with E71 consistently having the highest emergence. In the 3 and 5
h treatments, lower seedling emergence occurred for T1, X15, and X117, with X15
having the least emergence in the 5 h treatment.
Final stand establishment differed among genotypes across treatment durations.
In the control treatment, final stand of E71 was significantly greater than X15
and X117. All genotypes produced greater stands than X117 in the 1 h
treatment. For the 5 h treatment, E71 had significantly greater stands than
the other genotypes. In the 5 h treatment X15 produced the lowest final plant
stands.
Initial emergence and final stand establishment differed significantly between
treatments (Table 2). Compared to the control, seed and seedling performance
were adversely affected in the 3 and 5 h treatments. Post-emergence
damping-off in the 3 h treatment was observed to be significantly greater than
in the untreated control and 1 h methanol treatments.
Genotypes differed significantly in seed quality. When the control and 5 h
treatments were compared, stand reductions due to artificial aging were
greatest for X15 (43.2 vs 24.8%) and T1 (50.7 vs 30.5%). Except for T1,
emergence and final stand were not severely reduced until seeds were soaked
with methanol for 3 h. Although X117 exhibited poorest seed quality in the
untreated treatment, T1 and X15 showed the greatest deterioration when exposed
to the longer methanol treatments. These results suggest that methanol stress
may be used to artificially deteriorate kenaf seed for the evaluation of seed
quality. Such a methanol stress test may possibly be utilized as a selection
tool for genetically improving or for screening kenaf seed quality.
- Hernandez, V.H. 1987. Effects of cultivar, seed quality, pathogen virulence,
inoculum density, and seed depth on host resistance to the seed-seedling
disease complex of cotton. PhD diss. Texas A&M University, College
Station.
- Mugnisjah, W.Q. and S. Nakamura. 1986. Methanol and ethanol stress for seed
vigour evaluation in soybean. Seed Sci. Technol. 14:95-103.
Table 1. Effect of simulated aging by 20% methanol-water seed treatment
on initial plant emergence and final stand of five kenaf
genotypesz.
| Emergence (%)y | Final stand (%)y |
| Genotype | Genotype |
Methanol treatment (h) | E71 | T1 | C108 | X15 | X117 | E71 | T1 | C108 | X15 | X117 |
0 | 60.3ax | 55.8a | 52.3ab | 49.5b | 42.5b | 53.3a | 50.7ab | 46.2abc | 43.2bc | 36.8c |
1 | 57.5a | 55.6ab | 55.5ab | 48.8b | 39.0b | 51.1a | 48.9a | 48.7a | 45.5a | 36.7b |
3 | 52.0a | 39.8b | 47.8ab | 41.2b | 39.8b | 45.1a | 35.3b | 42.0ab | 36.1b | 36.3b |
5 | 44.2a | 33.6b | 35.4b | 26.7c | 34.3b | 40.4a | 30.5b | 31.3b | 24.8c | 30.3b |
zInitial plant emergence and final stand establishment were recorded
at 7 and 42 days after planting, respectively, and expressed as % of total seed
planted.
yCombined over the Weslaco and Monte Alto, TX locations.
xMeans in a row followed by the same letter are not significantly
different according to Duncan's multiple range test (P = 0.05). Data were arc
sin transformed for statistical analysis, actual means presented.
Table 2. Initial plant emergence, final stand, and post-emergence
damping-off of kenaf seed across five genotypes under 20% methanol-water
treatments to simulate artificial aging.
Methanol treatment (h) | Emergence (%) | Final stand (%) | Damping-off (%) |
0 | 52.1az | 46.0a | 21.5a |
1 | 51.3a | 46.2a | 22.2a |
3 | 44.7b | 39.0b | 25.4b |
5 | 34.8c | 31.6c | 23.9ab |
zMeans in a column followed by the same letter are not significantly
different according to Duncan's multiple range test. (P = 0.05). Data were
arc sin transformed for statistical analysis, actual means presented.
Last update April 23, 1997
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