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Some aspects of secondary seed size and primary:secondary seed weight ratios in Avena sativa L.Tibelius, Anne Christine Smith. January 1984 (has links)
The primary grain in oat spikelets is larger than the secondary grain. Oat genotypes were grown to determine the effects of planting primary and secondary grains separately on vegetative and reproductive growth. Plants from primary seeds had higher yields than those from secondary seeds. The advantage was associated with earliness of heading. It was concluded that increased seed uniformity would be advantageous. / Reductions in panicle size by removal of all primary grains and some secondary grains indicated that secondary grains have more growth potential than observed in untreated panicles. However, secondary grains in the treated panicles did not achieve weights equalling those of primary grains in the untreated panicles. / Variation in primary:secondary seed weight ratios was found among experiments. The variability was attributed mainly to instability of secondary grain weight. / The inheritance of secondary grain weight and of the primary:secondary seed weight ratio was studied at two locations. For both traits, additive and non-additive genetic effects were evident. Dominant gene action was relatively unimportant, suggesting good potential for improvement through pure-line breeding.
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Some aspects of secondary seed size and primary:secondary seed weight ratios in Avena sativa L.Tibelius, Anne Christine Smith. January 1984 (has links)
No description available.
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THE INFLUENCE OF SEED QUALITY ON GROWTH AND DEVELOPMENT OF THE COTTON PLANT.Alemayehu, Makonnen. January 1984 (has links)
No description available.
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Priming techniques and size characteristics of triploid and tetraploid watermelon seedLoehrlein, Marietta Margaret, 1957- January 1988 (has links)
Triploid and tetraploid watermelon seed are visually indistinguishable, increasing costs to growers, who cannot market the low-quality 4N melons. Efforts were made to separate 3N and 4N seeds by thickness and weight. Means in both cases were not separable. Successful seed 'priming' would be beneficial to seedless watermelon growers. Seeds from the open-pollinated 4N x 2N cross were primed in solutions of distilled water, polyethylene glycol '8000' (PEG), and potassium nitrate (KNO₃), or left untreated; treated seeds were subsequently dried for either 1 or 7 days. Seeds were scored for germination or emergence in the lab and for emergence under field conditions. Water was better than KNO₃ or PEG, but not always better than the control. One day in treatment was superior to 3 or 6 days; length of drying time was insignificant. In the field trial, treatments did not differ in emergence.
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Influence of etched seedcoats on the durability of soybean seed during conditioning, weatherability in the field, and the effect of cultural practices on the incidence of etched seedcoats in a seedlotBurchett, Clyde Alan January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
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Influence of vigor and seed source on soybean productivityIzaurralde, Maria Cristina Quiroga Jakas de. January 1984 (has links)
Call number: LD2668 .T4 1984 I92 / Master of Science
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Effects of delayed harvest on the quality of cotton planting seedHofmann, Wallace Craig January 1980 (has links)
No description available.
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Effect of seed quality on yield of Pima cottonSarmadnia, Gholam Hossein January 1979 (has links)
No description available.
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The relationship between soybean (Glycine Max (L.) Merrill) seed quality and the response to molybdenum seed treatmentBilbe, Sara Ann 12 1900 (has links)
Thesis (MScAgric.)--University of Stellenbosch, 2000. / ENGLISH ABSTRACT: Experi!11entsin KwaZulu-Natal showed that seed treatment with molybdenum
(Mo) could double the yield and increase the protein content by 1.9% of
soybeans grown on acidic soils. However, it was also found that soybean yield at
five of the localities was reduced on average by 8% after Mo seed treatment. It
was surmised that the yield reductions observed after Mo seed treatment were
connected to the quality of the seed used for planting. The aim of this project was
to assess the relationship between seed quality and Mo seed treatment and find
a fast, easy quality assessment test that could be used to adapt Mo treatments
according to seed quality.
The first investigation entailed assessing the quality of the seed obtained, from
various seed lots, for planting. A number of different seed quality testing
techniques were performed and they included the accelerated ageing test,
tetrazolium test, conductivity test, standard germination test and an emergence
. test planted at different depths with incubation at different temperatures. All the
test results were compared with the accelerated ageing test results, to find the
test most closely correlated to the accelerated ageing test, which is regarded as
the most accurate indicator of soybean seed vigour. It was found that the
emergence test where the seeds where planted at 10 cm presented a close
correlation with the accelerated ageing test. An assessment of seed quality
revealed that the four different seed lots provided seed of three significantly
different levels of quality, which could be used for further investigations.
The second investigation was concerned with the reaction of the seed of different
quality levels to Mo seed treatment. Firstly, seeds from four different seed lots
were treated with five different concentrations of Mo and planted under acidic
conditions. The establishment was monitored up until six weeks, at which point
the experiment was terminated. In the second planting, seeds from the four
different seed lots were treated with six different concentrations of Mo and planted under optimum pH conditions. Emergence was monitored and after
thinning out the remaining plants were left to mature and produce seed. The
emergence percentage results from both of these two plantings did not reveal the
alleged positive effect Mo seed treatment has produced in the field and no
definite relationship between seed quality and Mo seed treatment was observed.
The third investigation was concerned with the effect that osmoconditioning had
on the reaction of seed to Mo seed treatment. Seeds from two seed lots, one of
very poor quality and the other of good quality, were pre-treated with four
different levels of poly-ethylene glycol (PEG 6000) and then treated with four
concentrations of Mo. They were planted under optimum pH conditions and
establishment was monitored. After being thinned out the remaining plants were
allowed to mature and produce seed. The emergence percentage results
revealed that the PEG pre-treatments greatly improved emergence percentages,
especially in the poor quality seed. There were some positive effects of Mo seed
treatment observed where the lower concentrations of Mo were used, but again,
no definite relationship between seed quality and Mo seed treatment was found.
PEG pre-treatment appeared to help make the seeds more "resistant" to the
harmful effects of Mo. / AFRIKAANSE OPSOMMING: Navorsing in KwaZulu-Natal het aangetoon dat saadbehandeling met molibdeen
(Mo) die opbrengs van sojabone op suurgrond kan verdubbel en die
proteieninhoud met tot 1.9% kan verhoog. Daar is egter ook gevind dat
sojaboonopbrengs op vyf lokaliteite met gemiddeld 8% gedaal het na
saadbehandeling met Mo. "nVermoede bestaan dat die opbrengsverlagings wat
voorgekom het na saadbehandeling met Mo verband hou met die kwaliteit van
saad wat vir die aanplantings gebruik is. Die doel van die projek was om vas te
stel wat die verband tussen saadkwaliteit en Mo saadbehandeling is en om "n
vinnige en maklike toets te vind om saadkwaliteit te bepaal om sodoende Mo
behandelings aan te pas volgens saadkwaliteit.
In die eerste eksperiment is die kwaliteit van verskillende saadlotte wat verkry is,
getoets. "n Aantal verskillende tegnieke om saadkwaliteit te bepaal is uitgevoer.
Die tegnieke was die versnelde verouderingstoets, tetrazoliumtoets,
konduktiwiteitstoets, standaard ontkiemingstoets en "n vestigingstoets waar saad
op verskillende dieptes geplant en by verskillende temperature geïnkubeer is.
Die resultate van die verskillende toetse is gekorreleer met die resultate van die
versnelde verouderingstoets, wat beskou word as die toets wat die beste
aanduiding gee van saadgroeikragtigheid. Daar is gevind dat sade wat 10 cm
diep in sand geplant is, se opkoms die beste korrelasie met die versnelde
verouderingstoets toon en dus as "n goeie aanduiding van die kwaliteit van saad
beskou kan word. Daar is gevind dat daar drie saadlotte is met duidelike
kwaliteitsverskille wat gebruik kon word in verdere eksperimente.
Die tweede eksperiment het die reaksie van saad van verskillende
kwaliteitsvlakke teenoor molibdeen saadbehandeling ondersoek. Eerstens is
saad van vier verskillende saadlotte behandel met vyf verskillende konsentrasies
Mo en onder baie suur toestande geplant. Die vestiging is gemonitor vir ses
weke waarna die eksperiment gestaak is. Daarna is saad van dieselfde vier saadlotte behandel met ses verskillende Mo konsentrasies en onder optimum pH
toestande geplant. Vestiging is gemonitor en na ses weke is die plante uitgedun
en twee plante per pot is gelaat om saad te produseer. Die
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vestigingspersentasie van beide die eerste en tweede plantings het nie die
verwagte positiewe effek teenoor Mo saadbehandeling getoon nie en geen
betekenisvolle verwantskap tussen saadkwaliteit en Mo saadbehandeling kon
waargeneem word nie.
Die derde eksperiment het die invloed van osmokondisionering op die reaksie
van saad op Mo saadbehandeling ondersoek. Saad van twee saadlotte, een van
goeie kwaliteit en een van swak kwaliteit, is voorafbehandel met poli-etileen glikol
(PEG 6000) en daarna met vier konsentrasies van Mo behandel. Die sade is
onder optimum pH toestande geplant en die vestiging is gemonitor. Nadat dit
uitgedun is, is die oorblywende twee plante gelaat om saad te produseer. Die
vestigingspersentasies het getoon dat PEG voorafbehandelings vestiging
betekenisvol verbeter, veral in die geval van lae kwaliteit saad. Daar was 'n
. positiewe effek van Mo saadbehandeling waar relatief lae konsentrasies
molibdeen toegedien is, maar daar kon weereens nie 'n duidelike verwantskap
tussen saadkwaliteit en Mo saadbehandeling waargeneem word nie. Dit blyk dat
PEG voorafbehandeling die sade meer bestand teen die skadelike invloed van
Mo gemaak het.
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Germination and emergence salt tolerance of sorghum (Sorghum bicolor L.) as influenced by seed quality and generations.Alemayehu, Makonnen. January 1989 (has links)
Artificially aged and non-aged seeds of 22 grain sorghum (Sorghum bicolor L.) F₁ hybrids and their F₂ and F₃ generations were evaluated for germination salt tolerance. Six of the hybrids, along with their F₂ and F₃ generations, were tested for emergence salt tolerance. Effects of seed production environments on germination salt tolerance were also studied using F₂ generations of 12 sorghum hybrids produced under full-season irrigation, limited irrigation, and double-cropping conditions. Germination tests were conducted in a growth chamber, on trays, while the emergence test was conducted in a greenhouse in flats filled with sand. The experiments were conducted under non-saline and saline conditions in randomized complete block designs. Artificial seed aging resulted in significant reductions in germination percentages under both non-saline and saline environments. The overall mean reduction in germination caused by seed aging was more than twice as much under salinity stress as under the non-stress conditions (48 vs. 17%), indicating differential effects of salinity on different quality seeds. Entries that appeared to be resistant to seed aging also had higher germination percentages under salinity stress. Seed production environment influenced germination performance in both non-saline and saline environments. The overall mean germination percentages of sorghum seeds produced under three different field environments were significantly different from one another. Significant differences were observed in germination and emergence percentages within F₁, F₂, and F₃ generations. Except for the F₁ entries, however, emergence index differences within the F₂ and F₃ generations were not significant. Correlations between germination and emergence percentages in the non-saline and saline treatments were generally nonsignificant. This suggests that germination and emergence responses of sorghum may vary under different salinity levels and different environments.
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