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1.
Summary In the framework of a comprehensive Dutch research project the feasibility of hemp cultivation for paper pulp production is being investigated. This project also includes a hemp breeding programme which was initiated at CPRO-DLO in 1990. Hemp breeding is primarily aimed at improving bast fibre production since bast fibre is qualitatively superior to woody core fibre for paper pulp production. The progress of the ongoing breeding programme is hampered by the lack of knowledge on the inheritance of agronomic traits.The following traits were examined on 252 parental plants in 1991 and subsequently on their progenies in 1992: fibre content, plant height, date of flowering, stem diameter and cannabinoid contents. For each trait heritabilities were estimated and direct and indirect effects of artificial selection were studied.The heritability of bast fibre content was high and mass selection proved to be an efficient method causing no undesirable influence on other characters. Characters not directly related to bast fibre yield such as date of flowering, plant height and stem diameter were shown to have disadvantages as selection criteria for the improvement of bast fibre yield.The cannabinoids THC and CBD were studied, as the acceptance of hemp cultivation requires a low level. The content of THC, the psychoactive component can be successfully reduced by mass selection, but it is not certain that mass selection is the most efficient method.  相似文献   

2.
Vernalization and photoperiodism are two important physiological processes related to yield of many cool-season annual crops. The flowering response of 20 flax (Linum usitatissimum L.) genotypes to two vernalization regimes (vernalized and unvernalized) and two photoperiod treatments (10 and 14 h) was evaluated in a growth chamber study in 2010 and 2011. The results suggest that photoperiod, vernalization, and genotype all had an effect on earliness as measured by days to anthesis. Unlike flax grown in the Upper US Midwest and Canada, Texas flax is grown in the fall due to high spring and summer temperatures. Genotype interaction was observed with both vernalization and photoperiod. Specifically, flax genotypes from Texas (winter type) were sensitive to both vernalization and photoperiods for flowering. Texas genotypes delayed anthesis for 7 days or more in unvernalized seedlings, whereas flowering time of most other spring grown flax genotypes was unaffected by the vernalization treatments. Texas genotypes also delayed anthesis for 12 days or more under vernalized and short day conditions, whereas most other genotypes were not influenced by photoperiodism in vernalized seedlings. The selection for vernalization and photoperiodic sensitivity in Texas genotypes and introgression of these traits into recently adapted spring grown genotypes is needed for development of high yielding flax genotypes for southern Great Plains production areas.  相似文献   

3.
Nine polycross (PX) and nine different self (S1) progenies were randomly chosen from 43 selected tall fescue genotypes and evaluated for in vitro digestible organic matter (IVDOM), crude protein, neutral detergent fibre, acid detergent fibre and acid detergent lignin of whole plants, leaf blades and stems (stem plus leaf sheath) at each of four harvest dates in 1991 and 1992. Significant variation for all whole‐plant and leaf quality traits occurred among the PX progenies at the May harvest. Variation among S1 progenies was significant for almost all of the stem traits. Genetic variance components for both progeny groups were significant for almost all of the traits, confirming the presence of additive genetic variation. Heritability estimates on a progeny‐mean basis ranged from medium to high for almost all the traits of the whole‐plant and the leaf and stem fractions. The results suggest that spring would be the time at which direct selection for high IVDOM or low fibre content would be successful and that selection for leaf or stem quality traits improves whole‐plant quality. Selection for quality traits in the summer or in the autumn would be difficult since no significant genetic variability was found.  相似文献   

4.
S.R. Verma  M. Yunus  S.K. Sethi 《Euphytica》1998,100(1-3):15-18
Three populations of an intervarietal durum wheat cross IWP5308/PDW208, F5, F5BIP1 (population derived after intermating in F2) and F5BIP2 (population derived after intermating in BIPF1), were evaluated under three different agronomic environments for mean performance and stability of genotypes for grain yield, yield components and protein content. Though the biparental progenies indicated a higher mean performance, they did not differ significantly from progenies of the pedigree method for almost all characters. The biparental progenies, however, produced a higher number of stable genotypes for grain yield per plant, grains per ear and protein content. The F5 population had a higher number of stable genotypes for 1000 grain weight and number of tillers per plant. The BIP progenies also had a higher number of genotypes with above average mean performance, and many were significantly higher than the checks WH896 and WH542, compared with F5 progenies. Hence, in spite of high G x E interactions, the use of cycles of biparental mating and selection of top yielding lines on the basis of yield components can enable selection of stable genotypes with high protein content. Number of tillers per plant and 1000 grain weight were the yield component characters which made maximum contribution to phenotypic stability of the genotypes. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

5.
Reciprocal recurrent selection (RRS) exploits the genetic complementarity of dura populations of palms with a small number of large bunches and tenera/pisifera group of palms with large number of small bunches. An extra phase was introduced to RRS just after the second cycle of selection where outstanding dura derived from (DA3D × DA5D) combinations of the second cycle were self-pollinated for seed production. Best palms based on the phenotype were selected and crossed with pisifera of second cycle offspring of LM2T. [(DA3D × DA5D) self-pollinated × LM2T self-pollinated] progenies were field tested at La Dibamba (Cameroun) from 1987 to 1997. They were precocious with regard to the three-first years’ bunch yields (13.16–15.77 t/ha). Homogeneity for all bunch yield components and homogeneity for vertical growth were illustrated by low values of the variation coefficient (5.75–7.75%). The oil yield was 107% of the control against 115% from [(DA3D × DA5D) × LM2T self-pollinated] progenies of the second cycle of RRS, mostly due to poor mesocarp to fruit and poor oil to mesocarp ratios which led to a low oil extraction rate. The extra selection phase led mainly to homogenisation of progenies but also reduced the fruit quality. However, three progenies whose average oil yield represented 115% of the control (4.87 t/ha) in addition to their precocity can be released to oil palm growers. The extension of RRS did not fully meet expectations and poses the problem of its reliability.  相似文献   

6.
Breeding in oil palm aims mainly at improving palm oil yield. Short palms are also desired because they are easy to harvest and increase the economic life of the plantation. A total of 23 progenies from Deli × La Mé and Deli × PO 1097 P (Yangambi) crosses were field tested at La Dibamba Oil Palm Research Centre in Cameroon from 1988 to 1998. Oil yield components were measured on per palm basis from 3 to 9 years after planting, and the vertical growth at 6 years after planting. The mean oil yield of the trial was average, representing 102% of the control (3.515 t/ha), and the mean height 6 years after planting was 101% that of the control (88.0 cm). The analysis of variance detected differences among progenies for various yield parameters and vertical growth. The comparison of means showed clear separation of groups of progenies for oil yield at the juvenile period (3–5 years after planting). At maturity (6–9 years after planting), the groups of progenies were overlapping indicating that progenies were comparable each other. However, four precocious progenies and high oil yielding at maturity (119–122% of the control) in absolute values can be released to planters. Though their vertical growth represented 116–127% of that of the control, short pisifera palm are expected from parental selfs or crosses given the intrinsic heterozygosity of oil palm.  相似文献   

7.
Summary Two fibre plants are under cultivation in the European Union – flax on approximately 125,000 ha and hemp on approximately 15,500 ha in the year 2004. Seeds, hurds and especially fibres of hemp are used for further processing. The most important markets for hemp fibres produced in the EU are pulp and paper and the automotive industry. Just under 5% of the EU hemp fibres were used in the construction sector. Approximately 95% the whole production of 40,000 t of the hemp hurds are used as animal bedding and 95% of the estimated 6000 t per year hemp seeds are sold for animal feed, mainly as bird feed.  相似文献   

8.
Seed production in perennial ryegrass, Lolium perenne L., is low. Early selection for high seed yield carried out in spaced plants would be valuable for breeders, but only if this potential is also expressed in derived progenies sown later in drilled plots. Therefore, spaced-plant traits assessed on clonal ramets of 31 genotypes in each of two perennial ryegrass varieties in four environments were related to seed production characteristics in drilled plots of open-pollinated progenies of these plants. Significant differences were found among these half-sib families for seed yield, thousand-grain weight, spring performance and earliness. The number of spikelets per ear in the maternal plants was negatively correlated with the seed yield of the progenies, explaining 17 % of the variation for seed yield in the cv. ‘Barenza’ and 14 % in the cv. ‘Wendy’. Multiple regression analyses revealed that no combinations of plant traits consistently explained a major portion of the variation for seed yield of the progenies. The results indicate that in these varieties, spaced-plant data are of limited value in predicting seed production. Direct selection for seed yield in drills of progenies in later stages of the breeding programme remains the best method for obtaining varieties with sufficient seed production.  相似文献   

9.
为了进一步明确播期对胡麻产量、品质和农艺性状的影响,本研究选用5个胡麻品种,设置4个播期,调查了产量、品质和农艺性状相关的15个性状。结果表明：（1）随着播期的推迟,5个胡麻品种的单产显著减少,籽粒的营养物质主要表现为减少趋势,其中棕榈酸含量能够保持稳定或略有增加;（2）‘坝选十六’和‘选三’的单产在4个播期均高于其他品种,其中‘坝选十六’的单产最高,而且含有丰富的亚麻酸、亚油酸、蛋白质、木酚素等营养物质,含油率较高,为供试品种中的最佳品种。本研究进一步量化了播期对胡麻产量、品质和农艺性状的影响,早播有利于获得高产、增强品质,并且筛选出‘坝选十六’为最佳品种,为胡麻生产的良种良法配套提供理论依据。  相似文献   

10.
Renewed interest in natural fibres, decreasing subsidies to European producers, and high production costs have led the move to reintroduce fibre flax (Linum usitatissimum L.) production into eastern Canada. Research was conducted at the Macdonald Campus of McGill University, Québec, Canada in 1998 and 1999 and at Winchester and Kemptville, Ontario, Canada in 1998, to assess the performance of seven European fibre flax cultivars. Parameters evaluated included plant density, branching ratio, stem diameter, fresh and dry biomass, and mean harvest height. Data from all sites and years were subjected to a pooled anova where appropriate. The cultivar main effect was detected for all parameters measured, with the exception of mean fresh weight and mean height at harvest. There was also a site main effect for all parameters except for branching ratio. A cultivar–site interaction was found for all parameters except for mean stem diameter and mean dry weight. Results indicate a strong potential for producing fibre flax in eastern Canada using currently available European cultivars.  相似文献   

11.
The purpose of this study was to investigate variation of and relationships among seed colour, seed weight and seed oil content in cultivated flax (Linum usitatissimum L. ssp. usitatissimum). Seed from 2934 flax genebank accessions recently grown at Saskatoon, SK, Canada, originating from 72 countries was used to describe the variation of the seed characters. The dominant seed colour of the accessions was medium brown (2730 accessions, 93.0%), followed by yellow (126 accessions, 4.3%). Based on single observations for all accessions, the overall mean and standard deviation was 5.95 ± 1.22 mg/seed for seed weight and 38.3 ± 1.74% for oil concentration. Within three infraspecific groups of flax, seed weight, oil concentration and oil amount per seed increased in the following order: fibre flax (convar. elongatum), intermediate flax (convar. usitatissimum), large‐seeded flax (convar. mediterraneum). The world collection exceeded the range of variation of seed weight and oil concentration found in 52 North American cultivars. There was a weak, positive association of higher oil concentration with higher seed weight (r2 = 0.32; P < 0.001). Yellow‐seeded flax had a higher seed weight (6.31 vs. 5.92 mg/seed) and oil concentration (39.4% vs. 38.3%) than brown‐seeded flax. There was a tendency for yellow seed colour to be associated with higher oil concentration in all seed weight classes. The results suggested that indirect selection for increased seed oil concentration in flax is possible by selection for higher seed weight and yellow seed colour.  相似文献   

12.
Successful castor (Ricinus communis L.) cropping in Greece depends on the yielding ability and yield stability of the cultivars (hybrids or inbreds) as well as the reliability of production systems. The adaptation and yielding ability of 19 modern castor oil genotypes were studied for 3 years in two sites of Northern Greece. Genotypes combining high seed and oil yield and desirable morphological characteristics were tested for 2 or 3 years, whereas the rest were tested for 1 year only. The growing period in both locations was long enough for ripening the first raceme and a number of secondary racemes depending on the genotypes. The plant height was dependent mainly on the genotypes but also was affected by the site and the year of the experimentation and ranged from 79 to 278 cm. The seed yield varied between 2.5 and 5.0 Mg ha−1, values that are among the highest reported in the literature. The seed yield was higher in the site where plants produced and ripened more secondary racemes. The seed oil content was dependent mainly on the genotype and ranged from 44.5 to 54.2%. The oil yield followed the changes in seed yield. The variation in seed yield between years was low and in most genotypes less than 20%. Results indicate that the castor oil crop was satisfactorily adapted in the area.  相似文献   

13.
喷施硒肥对胡麻子粒硒含量、产量及品质的影响   总被引：2，自引：0，他引：2  
以晋亚10号胡麻为试验材料,研究盛花期和青果期两次喷施不同剂量的硒肥对胡麻子粒硒含量、产量和品质的影响,为富硒胡麻栽培提供科学依据。供试硒肥有机硒含量6g/L,共设置6个硒肥剂量,分别是1 500mL/hm 2（T1）、3 000mL/hm 2（T2）、4 500mL/hm 2（T3）、6 000mL/hm 2（T4）、7 500mL/hm 2（T5）和清水对照（T0）。结果表明,叶面喷施硒肥能显著提高胡麻子粒硒含量,且随着硒肥喷施量的增加,胡麻子粒中的硒含量逐步增加,T5处理胡麻子粒中硒含量最高,达0.507mg/kg,是对照组胡麻含硒量的18.1倍。适量喷施硒肥能显著提高胡麻产量,具体表现是随着硒肥喷施量的增加,胡麻子粒产量先增加后减小,T4处理产量最高,达858.2kg/hm 2,比对照增产9.5%。结论喷施合适剂量的硒肥可以提高胡麻子粒硒含量和产量,且对胡麻品质影响较小。综合分析,以有机硒含量6g/L的硒肥在盛花期和青果期进行两次喷施,6 000mL/hm 2为胡麻叶面喷施硒肥的最佳施用量。  相似文献   

14.
胡麻栽培技术的研究进展   总被引：6，自引：3，他引：3  
胡麻油质优良、营养价值丰富,抗逆性强、适应性较广,是中国主要的油料作物。长期以来,粗放的栽培技术、落后的管理措施等导致胡麻产量低、品质差。为了促进胡麻生产实现高产优质,介绍了胡麻的应用价值和栽培特性,重点阐述了胡麻的适时播种、平衡施肥、间套作以及地膜覆盖等栽培技术,探讨了目前中国胡麻的生产现状和存在的问题,并提出了今后的发展对策,旨在为快速推进胡麻生产和栽培技术研究提供理论参考。  相似文献   

15.
Flax is an established crop in many parts of the world due to its positive health effects and numerous industrial uses. Due to increasing interest in biofuels, flax has been evaluated throughout the U.S.A. as a potential biodiesel crop. The main purpose of this research was to evaluate current and historical genotypes of flax in different regions of south‐east Texas. Twenty genotypes of flax were evaluated under dryland conditions for their agronomic and yield potential in College Station and McGregor, TX starting in 2008 thru 2011. The results suggest that all genotypes developed in Texas showed acceptable cold tolerance compared with genotypes developed in other locations. There were significant genotype–environment interactions (P < 0.001). A cross between Caldwell/Dillman (Texas genotype) was highly adapted to the environments of south‐east Texas. Nekoma and York (genotypes developed in North Dakota) yielded well in non‐cold years (>28 °F) at College Station. Utilization of cold tolerance trait identified in Texas genotypes coupled with high yield potential of modern genotypes would have a significant impact on yield improvement of flax in south‐east Texas. Overall, flax is well adapted to growth in the area surrounding College Station, TX and has potential as an oilseed crop for production in south‐east Texas.  相似文献   

16.
H. Baydar    R. Marquard  I. Turgut 《Plant Breeding》1999,118(5):462-464
The aims of this study were estimation of the variability of seed yield, oil content, oleic acid and linoleic acid content in single plant progenies and lines derived from Turkish sesame populations, and the improvement of different type lines with regard to high seed yield, high oil content and specific fatty acid composition. Different types of lines were developed—i.e. lines which yielded over 1000 kg seeds/ha from the yield type progenies and lines which yielded over 63% of oil content from oil type progenies—but it was not possible to improve lines where fatty acid composition differed dramatically from that of oleic and linoleic type progenies.  相似文献   

17.
Cocoa butter is the major commercial product from seeds of Theobroma cacao (cacao). However, most cacao breeding programs have only considered as selection criteria total seed yield per plant and disease resistance. Progress in cocoa butter yield might be possible if variability for fat content exists and its associations with the other production components are established. The average fat content in dry unfermented seeds for 490 accessions of the Centro de Pesquisa do Cacau germplasm collection in Ilhéus, Bahia, Brazil was 53.2%, ranging from 45.4% in CC 57 to 60.3% in NA 312. Fat content averaged over series indicated that genotypes originally collected in the Upper Amazonian region had higher fat levels, while the Trinitario-Criollo and Bahian genotypes tended to have lower fat content. When considering total fat yield plant-1 an opposite trend arose with the series with low fat content having the highest total fat yield. The correlation between fat content and fat yield plant-1 was not significant, while there was a significant negative correlation between dry seed yield plant-1 and fat content. Despite the significant negative association between fat content and dry seed yield plant-1, the correlation coefficient was rather low, and genotypes could be identified with both high fat content and dry seed yield. A significant pollen effect on fat content was observed based on a complete diallel crossing scheme between three genotypes with high and three with low levels. The average fat content values in progenies were similar to the average of the parents, and the segregation range transgressed the distribution of the parents. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

18.
An essential quality improvement of rapeseed oil can be obtained by reduction of its linolenic acid (C18:3) content from about 10% to less than 3% of the total fatty acids. Genotypes low in C18:3 have been developed by mutagenesis. The initial summer rapeseed mutant had been low yielding and highly susceptible to various diseases. It has been debated whether the low C18:3 character can be successfully combined with high seed yield for physiological reasons. Therefore, the low linolenic character of mutant M48 was transferred into high-yielding genotypes by repeated backcrossing to well-adapted low erucic acid, low glucosinolate (00-) winter rapeseed cultivars. Lines with low C18:3 content were selected from BC3 and BC4 generations and examined in 1990–95. Positive selection response for seed yield was shown to continue over the years. Presently, the best lines are yielding as well as the control cultivars being equivalent also in oil and glucosinolate contents. In order to test the effect of a low C18:3 content on seed yield, plants with low and with high C18:3 content, respectively, were selected from 16 segregating BC5-F2 populations and bulked to form 32 F3 populations. These ‘isogenic’ bulk populations were tested for field performance at four locations in 1995. The results show that C18:3 content of the seed oil is not associated with seed yield, oil content, beginning of flowering, plant height and disease resistance. Means of relative seed yield for the high and the low linolenic F3 bulk populations were not significantly different with 88.0% and 86.9% of the control cultivars, respectively. There was a significant interaction between genotypes with high or low C18:3 content and location. This shows that under specific environmental conditions a low C18:3 content may be either favourable or unfavourable. The results indicate that the low C18:3 character of the original mutants per se does not cause a decrease in seed yield, oil content or general field performance.  相似文献   

19.
Flax plants were studied at two old sites (Kafer El-Sheikh and El-Fayoum) and a new site (El-Salhia). At the harvesting stage soil samples were collected and subjected to mechanical, physical and chemical analysis. The fibre yield, physical and chemical characteristics were studied and correlated with the major edaphic conditions of the old and new sites. The results indicate that the fibre yield and quality were quite high in the flax from the Kafer El-Sheikh site because of suitable climatic conditions and high fertility of the soil. Soil build up of the old site at El-Fayoum enhanced slightly high fibre strength and fineness, in spite of less fevourable climatic conditions compared to the El-Salhia site. Low organic matter and availability of nutrients in addition to high calcium content were the main factors affecting the quantity and quality of the flax fibre in the new cultivated area at El-Salhia.  相似文献   

20.
The feasibility of producing fibre flax in minimum tillage or zero tillage (ZT) systems was investigated. The results were variable between the sites, which differed in soil type and previous cropping history. Tillage regime had no impact on fibre flax phenological development including number of days to emergence, days to flowering and days to harvest at either site. However, tillage regime had a significant effect on mean stem diameter, dry matter content and plant height at all three sampling dates at the sandy loam site, and a significant effect on mid‐season plant height at the clay site. At the sandy loam site, ZT plots had the highest populations of plants with the finest stem diameters, the lowest branching ratios, but the shortest plants by the end of the season. Overall, plant densities were greater, stem diameters thinner, and biomass production higher in the heavier soil of the clay site. These results indicate that under the growing conditions present in 1998, fibre flax can successfully be grown in minimum or ZT systems on different soil types in Eastern Canada. Moreover, the growth of fibre flax in these systems does not compromise the proportion of tall plants having thin stems and minimal branching, a critical quality parameter for fibre flax production.  相似文献   

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