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Studies on changes in the early stage of germination of glycine max (L.) Merr.January 1985 (has links)
by Lee Yuen Chong. / Bibliography: leaves 112-131 / Thesis (M.Ph.)--Chinese University of Hong Kong, 1985
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Nutritive value of sunflower seed for swineLaudert, Scott January 2011 (has links)
Digitized by Kansas Correctional Industries
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Evaluation of bean cultivars under high temperature stressUpson, Steven Douglas January 2011 (has links)
Photocopy of typescript. / Digitized by Kansas Correctional Industries
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Quantitative changes in certain constituents of corn grain during germinationJassim, Maysoon Najeeb January 2011 (has links)
Photocopy of typescript. / Digitized by Kansas Correctional Industries
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Dormancy and germination of true potato (Solanum tuberosum L.) seeds : characterization of endo-β-mannanase genesMonteros, Alvaro R. 06 December 2002 (has links)
True potato (Solanum tuberosum) seed (TPS) is used for preservation of
variable genetic lines of wild and cultivated potatoes (Hawkes et al., 2000) and for
propagation of food crops in some developing countries. TPS has advantages over
seed potato tubers in storage and transportation and favors lower virus infection
levels in fields. However, TPS has thermodormancy and will not readily germinate
at 25°C and above (D'Antonio and McHale, 1988; Pallais, 1995a, b; Alvarado et
al., 2000). TPS can be extremely unreliable when planted directly in fields due to
poor emergence related to diseases and soil crusting.
Germination tests were conducted with two lots of TPS derived from cvs.
EB-8109 and All Blue, respectively, to study dormancy mechanisms. Seeds were
germinated under four temperature regimes (10°C, 15°C, 20°C and 25°C). The two
lots showed distinctly different germination characteristics. EB-8109 seeds showed
only thermodormancy whereas All Blue seeds showed very deep dormancy.
A carotenoid synthesis inhibitor, fluridone, which blocks abscisic acid
(ABA) synthesis, effectively broke thermodormancy in EB-8109 TPS but did not
break primary dormancy in All Blue seeds. Additional treatments, including pre-chilling
and hormonal regimes, also failed to break All Blue deep dormancy. When
the micropylar region of the endosperm (endosperm cap) was removed from seeds
of both seed lots, radicle elongation was observed, suggesting that mechanical
resistance from the endosperm cap restrains radicle protrusion, and that weakening
of the endosperm cap is requisite for TPS germination.
Endo-β-mannanase expression was measured to help characterize
mechanism underlying the weakening of endosperm cap tissues. This enzyme is
thought to permit radicle protrusion by degrading cell walls thereby weakening the
tissues of the endosperm cap (Groot et al., 1988). The coding region of
germination-specific mannanase was isolated from the potato genome by use of
polymerase chain reaction (PCR) with primers specifically designed for the tomato
germination-specific mannanase gene (LeMAN2, Nonogaki et al., 2000). The
cDNA of the TPS mannanase was identical to that of LeMAN2. The expression of
mannanase mRNA was detected in the endosperm cap of germinating TPS after 72
h of imbibition at 15°C, while no expression was detected at 25°C (thermodormant
condition). Fluridone induced mannanase expression in the micropylar region of
the endospem at 25°C. Thus, there was a correlation between induction of
mannanase and dormancy breakage.
A major increase in TPS post-germinative endo-β-mannanase activity was
detected by use of gel diffusion assay. Two isoforms of mannanases were detected
in the protein extracts of germinated TPS by activity staining of native
polyacrylamide gel electrophoresis. The post-germinative mannanase was detected
in the whole endosperm of germinated TPS by using tissue printing with the
LeMAN1 (Bewley et al., 1997) RNA probe. These results suggest that, as with
tomato, TPS also expresses post-germinative mannanase activity.
The promoter region of a new tomato mannanase was isolated during this
research. This promoter was shown to be involved in anther-specific expression of
mannanase. / Graduation date: 2003
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Post-dispersal seed fates in a Western Oregon native prairieClark, Deborah L. (Deborah Louise) 17 April 1996 (has links)
Knowledge of post-dispersal seed fates and other regeneration characteristics is
crucial for predicting abundances and distributions of populations and, ultimately,
community species composition and diversity. Seed fate studies, however, are rare
primarily due to the difficulty of determining seed fates and causes of mortality.
This thesis investigated post-dispersal seed fates for four species common to
western Oregon native prairies: Bromus carinatus Hook and Am. var. carinatus,
Cynosurus echinatus L., Daucus carota L., and Prunella vulgaris var. lanceolata
(Barton) Fern. The general approach was to sow seeds of these species into
experimentally manipulated field plots for each of two years, and to recover these seeds
from the soil one year later to determine their fates (persistence, death, or establishment
as seedlings). The effect of mowing on seedling establishment was also addressed.
Additional studies focused on the effects of a single mortality factor, fungal disease, on
seed and seedling deaths.
The fate of most seeds was death (44%-80%). Few seeds established as seedlings
(4%-17%), and mowing did not significantly increase seedling establishment. Only
Daucus carota formed a persistent seed bank.
Fungal disease generally caused less than 10% mortality. Pot studies
corroborated these field results. Other investigators have suggested higher levels of
disease in natural vegetation.
Vertebrate predation significantly reduced seed numbers for only Bromus
carinatus (21%). The largest cause of death for all species for both years was the
combined group of other mortality causes (invertebrate predation, interference, and
abiotic factors) (52%-73%). The components of this combined group, however, differed
among species. The most likely components for Bromus carinatus and Cynosurus
echinatus were interference (competition plus allelopathy) and abiotic factors, although
invertebrate predation cannot be ruled out for Bromus carinatus. Seedling death due to
abiotic factors was most likely the largest component for Daucus carota. The most
probable components for Prunella vulgaris were invertebrate predation and abiotic
factors.
Implications of these findings for population patterns and for restoration of native
prairies are discussed. / Graduation date: 1996
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Flowering, seed maturation, and harvest timing for turf-type tall fescueAndrade, Ronaldo Pereira de 17 December 1993 (has links)
Graduation date: 1994
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De fructibus et seminibus ex formatione lithanthracumBerger, Reinhold, January 1900 (has links)
Thesis (doctoral)--In Universitate Viadrina, 1848. / Vita. Includes bibliographical references.
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Breaking barriers of regeneration examining the effectiveness of bird perches in facilitiating seed dispersal in a tropical dry forest /Muldrow, Milton, January 2007 (has links)
The entire thesis text is included in the thesisfinalFINAL_(2).doc file; the title page, table of contents, and figures and illustrations list are included in the coverpages_(2).doc file. Title from title page of Word Document (University of Missouri--St. Louis, viewed March 1, 2010). Includes bibliographical references (p. 22-27).
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Seed dispersal, seedling emergence and bird community structure in a human-modified landscape mosaic in Sri LankaMogollones Barrera, Sol C. January 2013 (has links)
No description available.
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