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1.
R. N. Kulkarni 《Euphytica》1990,47(2):147-151
Summary Honeycomb and simple mass selection for herb yield and inflorescence to leaf + stem ratio were studied in a population of palmarosa (Cymbopogon martini Stapf. var. motia) grown at a plant spacing of 90 cm. The inflorescence to leaf + stem ratio was studied for indirect selection for oil content. The effects of selection were evaluated at high (30×30 cm) and low (45×45 cm) plant densities. Honeycomb selection was effective in improving herb yield at both plant densities while simple mass selection was effective only at low plant density. Both selection methods were equally effective in improving inflorescence to leaf + stem ratio but only when the populations were grown at low plant density. Increases in oil content were obtained even when selection for an increased inflorescence to leaf + stem ratio was ineffective. Improvements in each of the three studied traits did not affect any other studied trait. 相似文献
2.
Vernonia galamensis is a wild plant from the family Asteraceae which is endemic to East Africa and has the potential to become a new oil crop for industrial uses. Its seed oil is rich in vernolic acid, a fatty acid of high interest for oleochemical applications. However, a breeding program for Vernonia galamensis cultivars with high seed and oil yields requires knowledge about the genetic variability of traits that influence seed and oil production. This study was undertaken to examine phenotypic and genotypic variability, broad-sense heritability, genetic advance under selection and interrelationships of agronomic and seed quality traits. A total of 122 Vernonia accessions, 115 collected from different regions of Ethiopia and seven introduced, were grown at two locations in Ethiopia (Alemaya and Babile), in 2001/2002 and were analyzed for 20 traits including phenology, yield, yield components, and seed quality with special emphasis on fatty acid composition. The collections exhibited significant variation for all traits except for days to emergence. Genotypes and locations interacted significantly (P 0.01) for all traits. Broad-sense heritability estimates ranged from 11% (for days to emergence) up to 79% (for days to maturity). Expected genetic advance was between 1.3% (for days to emergence) and 44.8% (for seed oil yield). Genetic correlation analysis revealed that seed yield per plant is highly and positively correlated with seed weight and head number; highly significant and negative correlations (r = –0.59, –0.82, –0.85, and –0.89) were found between vernolic acid and palmitic, stearic, oleic, and linoleic acid, respectively. Highly significant positive correlations (r = 0.55, 0.44, and 0.36) were observed between vernolic acid and oil content, meal protein content and seed oil yield, respectively. Path-coefficient analysis indicated seed weight and secondary head number to be the most important components of seed yield per plant. Vernolic acid, oleic acid and linoleic acid had positive direct effects and stearic acid had a negative direct effect on oil content. The direct positive effect of oleic acid on oil content was, however, compensated by the negative indirect effects of stearic and vernolic acid resulting in a negative correlation (r = –0.60) between oleic acid and oil content. These observations will support the selection of accessions with high seed and oil yield, high meal protein contents, and high vernolic acid content. 相似文献
3.
R. N. Kulkarni 《Euphytica》1994,78(1-2):103-107
Summary Phenotypic recurrent selection was carried out for oil content in East Indian lemongrass, Cymbopogon flexuosus (Steud) Wats. In each cycle, the top 5% of plants for oil content were selected. Their ramets were used for the establishment of replicated polycross blocks in isolation. Realized gains from selection were determined by evaluating the populations and the best clones from each population in separate two-year replicated trials. Three cycles of recurrent selection increased oil content by 32% per cycle at the population level. Realized gains from selection were slightly smaller or similar to predicted gains. Mean realized heritability for oil content was 0.56. At the clonal level, the best C1 and the best C2 clones had, respectively, a 22% and 73% higher oil content than the best clone from the base population (C0). Selection for oil content did not adversely affect leaf yield, dry matter content or citral content in oil. Probable reasons for the high response to selection are mentioned. 相似文献
4.
Five cycles of phenotypic recurrent selection for increased essential oil content were carried out in East Indian lemongrass, Cymbopogon flexuosus. In each cycle, the top 5% of plants for essential oil content were selected and their ramets were planted in isolated polycross blocks to produce the seed of the next cycle. Response to selection for essential oil content and its effect on three unselected traits, leaf yield, dry matter content in leaves and citral content in the essential oil, were determined by evaluating C0‐C5 populations in a replicated trial. Genetic variation, heritability estimates and intertrait correlations for essential oil content, leaf yield, leaf width, tiller number and citral content in the essential oil in C4 were determined, by evaluating 40 clones and their half‐sib progenies produced from 40 randomly selected C4 plants, in a replicated experiment. These were compared with those determined in C0 earlier. The mean essential oil content increased from 0.66% in C0 to 1.67% in C5 (i.e. by about 31% per cycle over C0). Selection for essential oil content did not affect leaf yield and its effect on dry matter content in leaves was marginal. The first three cycles of selection for essential oil content did not affect citral content in the oil but two further cycles significantly decreased citral content. Heritabilities and intertrait correlations between all traits studied, except citral content and essential oil content, were similar to those found in C0. 相似文献
5.
Nagawara Seshagirirao Ravindra Srinivas Iyer Ramesh Mahesh Kumar Gupta Tripta Jhang Ashutosh Kumar Shukla Mahendra Pandurang Darokar Raghavendra Narayanrao Kulkarni 《Journal of Crop Science and Biotechnology》2012,15(1):33-39
Patchouli (Pogostemon patchouli) is an important, exclusively vegetatively propagated aromatic plant, whose essential oil is widely used in perfumery and
cosmetic products. Forty SC1 generation (first generation following in vitro phase) somaclones selected randomly from about 400 somaclones developed from the variety Johore, were multiplied through
stem cuttings and evaluated in SC2 and SC3 generations to study the extent of somaclonal variation generated for plant height, herb yield, essential oil content, essential
oil yield, and seven constituents of the essential oil. Significant or highly significant somaclonal variation was observed
for plant height, herb yield, essential oil content, essential oil yield, and contents of patchouli alcohol, α-guaiene, α,δ-patchoulene,
and α-bulnesene in the essential oil. The number of somaclones significantly superior to the parental variety for plant height,
herb yield, essential oil content, and patchouli alcohol content in the essential oil ranged from 8–16 and the maximum superiority
over the parental variety for these traits ranged from 21–79%. Broad-sense heritability estimates of plant height, herb yield,
and essential oil content were 0.60–0.70 while those of essential oil yield and patchouli alcohol content were 0.44 and 0.47,
respectively. Heritability estimates of other studied essential oil constituents were generally low (0.12–0.38). A high positive
correlation was observed between essential oil yield and herb yield suggesting that selection for herb yield would be effective
in improving essential oil yield. Patchouli alcohol content in the essential oil was negatively correlated with all the studied
traits. Somaclonal variation, heritabilities of traits, and inter-trait correlations are reported for the first time in patchouli. 相似文献
6.
Summary A germ plasm collection of safflower, Carthamus tinctorius L., with about 900 lines from over twenty countries was evaluated in Utah, USA for head width and outer involucral bracts (OIB) dimensions, traits affected by both human and natural selection. The regional germ plasm pools contained considerable variability for these traits. Plants bearing short or long as well as narrow or wide OIB were well adapted. Geographical clines were detected for the means of OIB dimensions, indicating possible gene flow. The correlations of the OIB dimensions with yield, yield components, oil content and growing period were not instructive and at times very inconsistent. Primary head diameter varied considerably within the regional gene pools. Its correlations with yield/plant, number of heads/plant, seed weight and oil content were inconsistent. Capitulum width was positively and significantly correlated with the number of seeds per head. Head diameter, however, can vary considerably without affecting seed yield per unit area. 相似文献
7.
Summary Groat oil of oat (Avena sativa L.) is a well-balanced oil with respect to saturated, monounsaturated, and polyunsaturated fatty acids. In this study, we measured the effect of six cycles of recurrent selection for high groat-oil content on the fatty acid composition of the groat oil. From each cycle of selection, 50 oat lines were grown in a replicated field experiment at two sites and were evaluated for groat-oil content and fatty acid composition.Concentrations of palmitate and linolenate decreased moderately over cycles of selection, whereas stearate content increased. A major increase occurred in the content of oleate and a major decrease in linoleate. Most of the modification of fatty acid composition took place within the saturated and unsaturated classes. The ratio of unsaturated to saturated fatty acids increased over cycles of selection. Significant genetic variation was present for each fatty acid, indicating that selection for different desired fatty acid compositions in groat oil of oat should be possible in this population.Abbreviations GO
groat-oil content
- 16:1
palmitate
- 18:0
stearate
- 18:1
oleate
- 18:2
linoleate
- 18:3
linolenate 相似文献
8.
Summary An investigation was made to the interrelationships of agronomic and seed characters and their effect upon seed yield. Twenty genotypes of sunflower (Helianthus annuus L.) from diverse origin were studied in spring and autumn season, 1989.Most of the studied characters exhibited different relationships in spring and autumn seasons. The correlations between plant height and oil content, 100-achene weight and number of achenes per head and plant height and head diameter were, however, consistent in both seasons and across the seasons. Stepwise multiple regression analysis identified six relevant characters on which path analysis was done.Path analysis indicated that yield components like head diameter, number of achenes per head and 100-achene weight had comparatively smaller direct effects on seed yield (0.22, 0.15 and 0.23, respectively). Days to physiological maturity, plant height and oil content had relatively stronger direct effects on seed yield (0.33, 0.38 and 0.29, respectively). Days to physiological maturity, plant height and head diameter had considerable indirect effects. Head diameter, 100-achene weight and number of achenes per head were indentified as selection criteria for yield improvement. 相似文献
9.
Summary Four populations of linseed derived from five parents were advanced from the F2 to the F6 generation by SSD and to the F5 by pedigree selection. These populations were used to compare the efficiency of the two methods in order to provide superior genotypes with respect to grain yield and oil content, i.e. oil yield. The results showed minimum differences between pedigree and SSD lines for grain yield, where in only one cross the SSD lines were significantly superior to the pedigree lines. Since pedigree selection was carried out for both, seed yield and oil content, a positive response to selection was expected. However, early selection for yield, a character with low heritability, was not successful. On the contrary, significant differences for oil content were detected between the two groups of lines in three of the four crosses studied. In these cases the pedigree lines were superior to the SSD lines. These results demonstrate that strict selection in early generations for oil content, a character with comparatively high heritability, is feasible and successful in linseed. However, selection for seed yield should be postponed to later inbred generations. Consequently, in breeding for maximum oil yield of linseed a two-step selection procedure is recommended.Abbreviations PS
pedigree selection
- SSD
single seed descent
- TGW
thousand grain weight 相似文献
10.
Summary Dry seeds of palmarosa (Cymbopogon martinii
Stapf) var. motia were subjected to 12 doses of gamma rays ranging from 5 kr to 100 kr to find out the effects of gamma irradiation on growth parameters, herbage yield and yield and quality of essential oil. Several biological parameters such as seedling growth, pollen fertility, mitotic chromosome behaviour, productive tillers/plant, leaf area index, leaf/stem ratio (by fresh weight) and total herbage yield/ /plant together with yield and quality of oil have been studied in the first (M1) generation. Marked stimulatory effects of gamma radiation in 10 kr and 15 kr doses have been compared with the control for herbage yield, oil percentage and total alcohols (free geranyl and geranyl acetate).The two yield contributing traits, herbage yield/plant and leaf area index were remarkably increased in 15 kr, which indicates that in palmarosa the 15 kr dose is more effective than the higher doses in producing microlevel mutations. The yield and quality of oil at 10 kr and 15 kr doses were enhanced significantly. The results on high yield and quality of oil as induced by gamma-irradiation were discussed from the point of view that a gene may have been altered by mutagen treatment to produce a metabolic block between geraniol and geranyl acetate on the biosynthetic pathway or that modifier genes controlling the expression of a key precursor molecule may have been further modified to give rise to a geraniol rich chemotype in palmarosa. 相似文献
11.
Summary In order to assess the potential of Crambe hispanica, either in breeding programmes of C. abyssinica or as an oilseed crop in itself, 36 accessions of C. hispanica (29 of var. hispanica and 7 of var. glabrata) were grown in a greenhouse and evaluated for morphological characteristics, earliness, plant habit, seed characteristics and fatty acid composition. Four lines of C. abyssinica were included for reference. The 29 accessions of var. hispanica showed significant variation for all observed characteristics. Besides morphological characteristics, large variation was found for earliness, number of primary branches, seed yield, 1000 seed weight and volume, and linoleic, linolenic and erucic acid content. Morphological characteristics, earliness and plant habit did not show any high correlations with seed characteristics or fatty acid composition, except for seed hull (pericarp) mottling, which was related to a high oil and erucic acid content. The seven accessions of var. glabrata showed little variation. The large genetic variation in combination with promising figures for several characteristics, found in C. hispanica, may be useful in breeding programmes of the oilseed crop C. abyssinica, for which the available genetic variation is limited. Prospects of selection for high-erucic acid genotypes are discussed. Compared to C. abyssinica, both botanical varieties of C. hispanica are characterized by a cordate shape of the basal leaves, lack of seed retention and a lower DNA content. Plants of var. glabrata differed from var. hispanica in a sparsely hispid upper leaf surface and round stems and branches covered with a waxy layer. These clear differences and lack of success in intercrossing both varieties of C. hispanica strongly suggest that their taxonomic classification should be reconsidered. 相似文献
12.
Summary One hundred random oat (Avena sativa L.) lines from a base (C0) and each of three populations (C1, C2, and C3) improved for groat (caryopsis) oil content by phenotypic recurrent selection were evaluated for correlated changes in several unselected agronomic traits. In addition, the parents of the base population and four check varieties were evaluated for the same traits. Phenotypic recurrent selection for high groat-oil content resulted in no significant correlated response in mean expression of any trait. Mean grain yield, biomass, groat yield, and harvest index of the improved populations were equal or superior to the mean of the parents and, with the exception of harvest index, equivalent to the mean of the check varieties. Mean test weight and seed weight of all populations were lower than for parents or check varieties. Selection for high groat-oil content caused a decline in genotypic variance for test weight and groat fraction, but reductions in genotypic variance for heading date and plant height may have resulted from culling for good agronomic type. Broad-sense heritability remained moderate to high for all traits except groat fraction. Phenotypic and genotypic correlation coefficients revealed negative, though mostly nonsignificant, relationships between groat-oil content and several traits, which may reflect a purported bioenergetic limitation to increasing groat-oil content in oats. Oil yield, however, was positively correlated with grain and groat yield, groat fraction, biomass, and harvest index. Results suggest that development of high-oil oat cultivars with current levels of production traits via phenotypic recurrent selection is possible.Journal Paper no. J-13038 of the Iowa Agric. and Home Econ. Exp. Stn., Ames, IA 50011. Project 2447. 相似文献
13.
Increasing protein content is an important objective in breeding high protein oilseed yellow mustard (Sinapis alba L). The objectives of this research were to increase meal protein content, study population variation during three cycles of selection for increased meal protein content, and quantify the relationships of protein with oil and 1000‐seed weight. Recurrent selection was employed with half‐sib family evaluation in replicated field trials. Meal protein content increased by an average of 1 % per cycle. The correlation between meal protein and seed oil content was negative (r= ‐0.49 to ‐0.58). The population shifts, with selection, reflected successful increase of average meal protein content, and an increased frequency of genotypes with high meal protein content. Furthermore, simultaneous selection for meal protein and seed oil content was possible. The correlation between meal protein content and seed weight was positive (r= 0.29‐0.39) and thus selecting for increased meal protein content posed no risk of decreasing seed weight in this yellow mustard germplasm. 相似文献
14.
Summary Twenty nine strains of vegetable amaranth (Amaranthus tricolor were grown for two successive seasons to study different selection parameters for foliage yield and its nine contributing morphological and quality traits. The strains AV-38 (5.06 kg/plot) and AV-31 (5.04 kg/plot) recorded highest foliage yield, followed by AV-30 (4.78 kg/plot) and AV-23 (4.70 kg/plot). The protein and carotenoid content averaged 1.24 ± 0.03 mg/100 mg and 0.83 ± 0.02 mg/g respectively. The leaves of A. tricolor also have considerable quantities of ascorbic acid (112.33 ± 5.00 mg/100 g) and fibre (8.39 ± 0.10%). The mean of individual cuttings for plant height, leaf size, stem diameter, foliage yield, protein, ascorbic acid and fibre content increased with successive cuttings till third cutting and thereafter showed a decline. Genotypic coefficient of variation (GCV) values ranged from 6.80 to 28.25%. However, the fibre content, branches/plant, leaves/plant, plant height and stem diameter showed lowest values of GCV. The values of heritability estimates were high for all the traits in all the cuttings as well as on pooled basis and ranged from 0.89 for branches/plant to 0.98 for foliage yield. Highest expected genetic advance was noticed for ascorbic acid (57.48%), followed by foliage yield (48.30%) and leaf size (29.51%). 相似文献
15.
Summary The expected improvement in grain yield if selection was made for plant characters measured between flowering and maturity was evaluated in populations of rapeseed (Brassica campestris and B. napus) grown in a droughted environment. Drought was commenced at flowering in each species and measurements were made on plants at the commencement of the drought stress, during the stress treatment and at crop maturity.Substantial genetic and phenotypic variation was observed in yield as well as the different morphophysiological determinants of yield. In B. campestris no single parameter was found to be a suitable alternative selection criterion to yield since the correlated responses in yield if selection was for another character was lower than if selection was for yield alone. By the use of a selection index however, joint selection for yield, as well as harvest index, 1000 seed weight and seeds per pod, was expected to be 20% more effective than direct selection for yield under drought. In the B. napus population direct selection for flowering time or for harvest index was predicted to result in a genetic advance in yield equal to or greater than that obtained by direct selection for yield, whereas joint selection for flowering time and yield should result in a 16% greater yield increase. Selection for increased yield in these populations grown in droughted conditions is discussed. 相似文献
16.
Increases in the groat-oil content of oat (Avena sativa L.) increase the energy value of the grain and improve the feasibility of extracting oat oil for use as a vegetable oil.
Nine cycles of recurrent selection for greater groat-oil content conducted in a genetically broad-based oat population resulted
in dramatic increases in groat-oil content. Our objectives were todetermine if selection for greater groat-oil content affected
fatty acid composition, grain quality traits (test weight and seed weight), or agronomic traits (straw yield, biomass, harvest
index, heading date, and height). We evaluated 100 random lines from the base (C0) population and each of the nine selection
cycle populations in three environments in order to estimate means, genetic variances, heritabilities, and genotypic and phenotypic
correlations of grain quality and agronomic traits. We also evaluated 20 random lines from each population to estimate changes
in fatty acid contents. Oleate and stearate contents increased over cycles of selection, as did the ratio of unsaturated to
saturated fatty acids. Palmitate, linoleate, and linolenate contents and all grain quality and agronomic traits except harvest
index decreased over cycles of selection. There was no evidence for reduced genetic variance or heritability in C9 for any
trait, but the genotypic and phenotypic correlations between agronomic traits and oil content fluctuated over cycles. Selection
for increased groat-oil content improved oil quality but reduced grain quality and agronomic performance of the population.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
17.
Summary The relationships between yield, its components and other associated characteristics, both within and across generations, were studied in the F2, F3 and F4 of two Hard Red Spring wheat (Triticum aestivum) crosses using simple correlation, path coefficient and step-wise multiple regression analyses. In the F2 and F3 the plants were grown 50 cm apart from each other while in the F4 they were grown under the usual farm practices. Selection was practiced for high and low yield in the F2 and F3 mainly on the basis of individual plant yield. Statistically significant, but not always practically useful, correlations were found between yield and its components and other associated characters. The relationship between yield and protein content was negative and significant within all generations but not so between F2 (and F3) and F4. The intergeneration correlation coefficients between F4 grain yields and grain yields measured in the F2 and F3 were all positive and highly significant. These coefficients, which are also heritability estimates in standard units, were small in magnitude.Stepwise multiple regression analysis identified plant yield as the most significant factor in determining F4 line yield, followed by its components in the order of 1000-kernel weight, grain yield per plant and number of tillers per plant.Path coefficient analysis identified tiller number per plant and grain yield per spike as having strong positive direct effects on single plant yield. Harvest index of individual F2 plants can be used as an indirect selection criterion for yield. 相似文献
18.
J. Langbehn F. Pank J. Novak W.D. Blüthner Ch. Franz W. Junghanns C. Vender 《Euphytica》2001,118(1):83-90
20 accessions of marjoram (Origanum majorana L.)were characterized in two field experiments in Quedlinburg, Germany in 1997. The variation was assessed both on single
plants as a base for the development of pollinator inbred lines of a prospective hybrid variety system and also on plots on
a larger scale. The characterization comprised yield of leaf-flower fraction, content of essential oil and its proportion
of cis-sabinene hydrate. The anther status of the regrowth after the herb harvest was used as an indicator of male fertility. The
investigations revealed a high variability between and within accessions. The correlation of some traits is discussed as a
clue to indirect selection. The yield rises with increasing bush diameter of the single plants and with longer vegetation
periods caused by late flowering. Relations between the essential oil content and the duration of the vegetation period were
not consistent and could be caused by the environment. There were no relations between the anther status and agronomical or
physiological traits.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
19.
To develop efficient breeding strategies for the improvement of oil content and onset of flowering in Dimorphotheca pluvialis, narrow-sense heritabilities of these characters were estimated. Forty plant progenies were tested in 2 years and heritabilities were estimated from parent-offspring regression as well as from half-sib family variance components analyses. For oil content, the heritabilities estimated by means of parent-offspring regression were 0.36 and 0.33 for 1993 and 1994, respectively. The heritabilities obtained from the variance components analyses were 0.41 and 0.23 for the two years. Heritability estimates for onset of flowering showed more variation. From parent-offspring regression, the heritabilities were 0.72 and 0.37, and from variance component analysis the estimates were 0.53 and 0.19 for 1993 and 1994, respectively. The obtained heritability values and realized responses suggest that particularly in early selection generations, even with mass selection, considerable progress can be expected. Since correlation studies revealed neither phenotypic nor genotypic correlation between oil content and onset of flowering, selection for both characters can be undertaken independently. 相似文献
20.
Summary Within-plant variation was studied in seed samples of sesame (Sesamum indicum L.). Central and lateral capsules were sampled in three entries. Three capsule postions-basal (nodes 16 to 20), intermediate (nodes 21 to 25), and apical (nodes 26 to 30)-were sampled in four other entries. Nuclear magnetic resonance and gas liquid chromatography were used to characterize within-and among-plants variation in the same genotype for oil content and its fatty acid composition, respectively.Central capsules had heavier seeds, and their oil had more palmitic and oleic acids than had seeds from the two lateral capsules. However, central capsules had seeds with less oil content, and the oil had less stearic, linoleic, and arachidic acids than seeds from lateral capsules. Seed weight and arachidic acid were found to be constant in seeds from capsules located at different nodes along the plant. Oil content had a significant variation with capsule position along the plant in only one entry. Percentages of palmitic and linoleic acids were lower, and those of stearic, oleic, and linolenic acids were higher in seeds from the apical capsules. In almost all cases, capsules located in the intermediate and basal sections had a similar oil composition. However, there was a lack of consistency in the within-plant variation from plant to plant for the different traits studied. It was concluded that within-plant variation need be taken into account only if the experiment was set up to detect small differences between treatments. Among-plants variation was found to be influenced by plant genotype. 相似文献