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1.
Flowering phenology and sexual dimorphism are two major features that affect stem and seed production in hemp (Cannabis sativa L.), a short-day naturally dioecious plant. The sowing time is of primary importance because it affects flowering time and thereby influences stem yield. In spite of their unstable sexual phenotype, monoecious cultivars facilitate the harvest of both stems and seeds by reducing crop heterogeneity. The main objective of this paper was to determine the stem and seed yields for five monoecious hemp cultivars in relation to their flowering phenology and sex expression. Sowing was carried out on five distinct dates during 2007 and 2008 at two sites in Belgium. The duration from sowing to flowering in days, both stem and seed yields and the seed harvest index decreased when sowing was postponed from mid-April to the end of June. The stem and seed yields from the mid-April sowing (approximately 12.5 and 1.9 t ha−1, respectively) were within the ranges that were reported for fibre and both fibre and seeds production, respectively, in monoecious hemp. No interaction was observed between the sowing date and cultivar for both yields. Sex expression varied among cultivars, indicating that it might be selected, and was partly linked to earliness. Stem yields were lowest in the earliest cultivar (Uso 31) and highest in the latest one (Epsilon 68) while seed yields were lowest in the most masculinized and earliest cultivar (Uso 31) and highest in the most feminized and early (Fedora 17) or mid-early (Felina 32) ones. Both stem and seed yields correlated best with the duration from sowing to full female flowering or from sowing to the end of male flowering.According to our results, harvesting the seeds in addition to the stems in monoecious hemp requires early sowing and the selection of feminized early or mid-early cultivars, earliness depending on the climatic conditions in the cultivation area. Therefore, it might be agriculturally valuable to take sex expression into account in addition to earliness during the selection of cultivars that are adapted to a dual purpose. 相似文献
2.
黄麻纤维产量与主要农艺性状的相关分析 总被引：2，自引：0，他引：2
研究黄麻纤维产量与主要农艺性状的相关性, 可为高产育种与生产利用提供科学依据。本文159份不同来源黄麻种质资源的12个农艺性状对纤维产量即单株干皮重的影响表明, 各性状的变异系数变化在11.89%至38.50%之间, 表现出丰富的遗传变异。黄麻纤维产量与各性状均呈极显著正相关, 其中, 与单株鲜皮重、株高、始花期的相关系数较大, 分别为0.814、0.760和0.648。黄麻纤维产量和单株鲜皮重、株高、出麻率、鲜皮厚的回归方程达显著水平, 其标准回归系数依次为0.443、0.437、0.291和0.113。通径分析显示, 单株鲜皮重、株高在决定黄麻纤维产量时起主要作用。出麻率的相关系数(0.253)与直接通径系数(0.291)表现基本一致, 说明出麻率直接对黄麻纤维产量起作用, 具极显著正相关。因此, 在黄麻高产育种中, 应该以始花期、单株鲜皮重、株高、出麻率与鲜皮厚为主要筛选对象, 兼顾综合性状的改良。 相似文献
3.
Marcel A. J. Toonen Chris Maliepaard Theo H. Reijmers Hilko van der Voet H. Dick Mastebroek Hetty C. van den Broeck Michel J. M. Ebskamp Waltraud Kessler Rudolf W. Kessler 《Euphytica》2004,140(1-2):39-45
Summary Fibre formation in hemp (Cannabis sativa L.) is a dynamic process. In order to follow this process, the chemical composition of the hemp stem was studied during plant development using the acid and neutral detergent fibre and lignin methods. Additionally, near infra-red spectroscopy was carried out. To predict the chemical composition of the stem samples partial least square (PLS) analysis was carried out. The developed PLS models can predict the level of %ADF and %NDF in the hemp bast and core samples. For %ADL, the models are only suited for either core or bast tissues and can not be used for both tissues simultaneously. 相似文献
4.
随着测序技术的发展,主要麻类作物(黄麻、红麻、苎麻、亚麻和工业大麻)参考基因组从2011年至2020年陆续完成测序,这标志着麻类作物科学已经进入基因组时代。文章首先详细概述主要麻类作物基因组测序。其次,评述了基于基因组学的麻类作物重要应用价值基因挖掘。基于参考基因组和转录组测序,大量关于纤维发育、响应非生物胁迫的候选基因被挖掘,以促进麻类作物纤维的物种特性和“不与粮食争好地”的逆境农业。同时不同麻类作物特异性状候选基因陆续被报道,如红麻雄性不育、亚麻种子含油量和大麻大麻素相关候选基因等。再次,麻类作物基因组测序完成为基于组学的麻类作物遗传改良提供可能:有助于麻类作物种质资源形成和演化机制研究,系统解析纤维产量、纤维品质、抗病耐逆等农艺性状形成的分子基础;有助于建立高通量基因型-表型数据库,挖掘优异基因资源与创制新种质;有助于创新并集成分子标记辅助选择、基因组选择、转基因等技术,建立高效的快速育种技术体系。宜选育高产高效、抗逆抗病、适宜轻简化机械化、优质专用的多用途麻类作物新品种,以满足麻类作物相关产业的市场需求,适应麻类作物生产方式。尽管已经获得重要基因以及位点的信息,但如何高效率利用已有基因资源对麻类作物进行遗传改良仍需面临一系列挑战,如成熟稳定的遗传转化体系、麻类作物基因编辑体系构建及基因组选择育种等。 相似文献
5.
Paolo Ranalli 《Euphytica》2004,140(1-2):121-131
Summary Hemp is a multi-use crop, able to provide fiber, cellulose, seeds and seed oil, cannabinoid, and biomass. Integrating many agroindustrial chains, Cannabis is considered a crop model in which insights into specific metabolic pathways and biosynthetic processes are valuable for improvement of the plant for all sets of industrial derivatives. In this review the hemp breeding status is elucidated and many aspects are focused: (i) recovering, maintenance and characterization of genetic resources; (ii) widening of germplasm and genetic variability; (iii) marker-assisted selection and development of breeding programs; (iv) sexual differentiation; (v) monitoring of THC content. Modern hemp varieties for fiber and other specific end uses have been developed and new varieties are entering production. The scenario for the breeding advances in hemp relies on basic and applied research which provides insights to identify a strategy for the design of modified plants with enhanced performance. This is accounted by the dissection of traits into components and the modification of single steps of the related metabolic pathways. These advances are provided by genomic techniques and are able: (i) to identify key genes encoding enzymes and regulatory factors participating in cannabinoid, fiber and oil biosynthesis; (ii) to identify the mode of regulation of these genes; (iii) to characterize the function of the selected genes through higher, lower or specific expression incited by specific promoters. The identification of molecular markers for specific traits, gathered in a saturated linkage map, will have a remarkable impact on hemp breeding. The advances in basic and applied research make it possible to design methods for the identification of superior parents and cross combinations and the development of selection schemes that rely on less labour-intensive and time-consuming methods. 相似文献
6.
对４份毕节高支苎麻的主要农艺性状进行遗传分析的结果表明：鲜皮出麻率和单纤维支数等农艺性状具有较大的遗传力,可在早代单蔸（株）选择或直接选择,产量、鲜皮厚、茎粗等性状的遗传力较低,应根据各性状同相关关系进行间接选择或推迟到晚期世代选择。遗传变幅较大的性状有鲜皮出麻率、株高、单蔸产量等,由于性状的改良效果主要由性状的遗传力和变异幅度及选择强度所决定,因此,在５％的选择强度下,遗传改良效果好的性状为株高 相似文献
7.
为了明确大麻雌雄株之间的差异及为大麻全雌、全雄、雌雄同株育种提供理论依据,本试验以‘火麻一号’、‘汉麻5号’和‘汉麻2号’为试验材料,分析了大麻雌雄株之间原茎产量和农艺性状的差异及其相关性。结果表明,雌株的原茎产量比雄株高出18.18%~24.56%,差异显著;雄株的株高和节数分别比雌株高出了3.08~5.86 cm、0.28~1.92节,株高差异显著;雌株的茎粗和穗长分别比雄株高出了0.05~0.08 cm、3.35~4.90 cm,穗长差异显著;雌株的根长略高于雄株,而雄株的工艺长度比雌株高出了3.26%~5.55%,差异显著;雌株的茎干重、根干重分别比雄株高出了22.16%~27.06%、21.97%~31.91%,茎干重差异显著;雌雄株的节数、穗长及叶干重与雌雄株单株的原茎重呈负相关关系,雌雄株的株高、茎粗、根长、工艺长度及根干重与雌雄株单株的原茎重呈正相关关系。纤用工业大麻高产栽培技术及高产育种要以雌雄株比值小,叶少、节数少、穗短、株高和茎粗适中、工艺长度长、根干重及单株原茎重大作为主要目标。 相似文献
8.
Tariq Mahmood Muhammad H. Rahman Gary R. Stringam Francis Yeh Allen G. Good 《Euphytica》2007,154(1-2):101-111
A doubled haploid population of Brassica juncea, developed from a cross between two parental lines differing for days to maturity, was used to study the efficiency of indirect
selection for a primary trait through selection of secondary trait(s) over direct selection for the primary trait when quantitative
trait loci information is available for both primary and secondary traits, and applied. Days to maturity was considered as
primary trait, while days to first flowering, days to end of flowering, flowering period and plant height were considered
as secondary traits. An RFLP linkage map was employed for QTL analysis of maturity and maturity-determinant traits, and a
stable QTL B6 simultaneously affecting these two types of traits was identified. This linked QTL explained 11.7% phenotypic
variation for days to maturity, 20.7% variation for days to first flowering, 24.3% variation for days to end of flowering
and 14.4% variation for plant height. Phenotypic evaluation of maturity and/or maturity-determinant traits, viz. days to first
flowering, days to end of flowering and plant height revealed that limited genetic advance for early maturity can be achieved
through phenotypic selection of the primary and/or the secondary trait(s). However, the estimates of genetic advance for early
maturity based on combined phenotypic evaluation and linked QTL data was found to be, at least, three times higher compared
to genetic advance based on phenotypic evaluation only, demonstrating the potential of marker-assisted selection in breeding
for early maturity in B. juncea. 相似文献
9.
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
10.
Mary J. Guttieri Katherine Frels Teshome Regassa Brian M. Waters P. Stephen Baenziger 《Euphytica》2017,213(4):87
Wheat genotypes that efficiently capture and convert available soil nitrogen into harvested grain protein are key to sustainably meeting the rising global demand for grain protein. The purposes of this study were: to characterize the genetic variation for nitrogen use efficiency (NUE) traits within hard winter wheat adapted to the Great Plains of the United States and evaluate trends in the germplasm with year of release; to explore relationships among traits that may be used for selection within breeding programs; and to identify quantitative trait loci associated with NUE traits in this germplasm. NUE traits were measured in a panel of 299 hard winter wheat genotypes, representing historically important and contemporary germplasm, from across the growing region. Trials were grown in two years at two levels of nitrogen fertility. Genotype and genotype × year interaction effects were highly significant for NUE traits, while genotype × nitrogen rate interactions were non-significant. Strong genetic correlations of plant height and flowering date with NUE traits were observed. Wheat breeders have improved NUE: the subset of 183 genotypes that were released as cultivars after 1960 demonstrated significant trends with year of release for improved grain N yield, grain yield, nitrogen harvest index, nitrogen uptake efficiency, nitrogen utilization efficiency, and post-anthesis nitrogen uptake. In genome-wide association analyses, plant height and flowering date were important covariates in the mixed models, and plant height and flowering date substantially explained the variation in NUE traits in this germplasm. Marker-trait associations were identified that may prove useful in breeding. 相似文献
11.
Identification of genic SSRs in jute (Corchorus capsularis,Malvaceae) and development of markers for phenylpropanoid biosynthesis genes and regulatory genes 
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下载免费PDF全文 Pratik Satya Avrajit Chakraborty Sourav Jana Snehalata Majumdar Maya Karan Debabrata Sarkar Subhojit Datta Jiban Mitra Chandan S. Kar Pran Gobinda Karmakar Nagendra K. Singh 《Plant Breeding》2017,136(5):784-797
12.
In the development of new crops such as Dimorphoteca pluvialis (L.) Moench, improvement of flowering synchronisation is an important breeding objective. The flowering of single plants
of Dimorphotheca pluvialis could be described by a logistic curve obtained by the regression of cumulative number of open flowers on time. The curve
is characterised by three parameters, corresponding with the total number of flowers produced by the plant, the rate of flowering
development and the day at which peak bloom is reached. From these parameters two other characteristics were derived, i.e.,
onset of flowering and duration of flowering. The use of the flowering model for selection for improved flowering synchronisation
is discussed. Heritabilities of flowering traits were estimated using parent-offspring regression and variance components
analyses. Onset of flowering and date of peak bloom showed high (>0.69), and total number of flowers moderate to high (0.30–0.90)
heritability values, indicating that for these traits considerable progress may be expected from mass selection, particularly
in the early selection generations. Duration of flowering showed low to moderate values (0.25–0.45), and methods other than
mass selection (e.g. family selection) should be considered. Determination of phenotypic and genetic correlations revealed
only an additive genetic correlation between date of peak bloom and duration of flowering (r
A
= 0.80 and 0.69 for 1993 and 1994, respectively), suggesting the possibility of indirect selection for curtailed duration
of flowering by means of selection against late date of peak bloom. Duration of flowering, total number of flowers and onset
of flowering were not correlated.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
13.
The phenotypic variability and adaptability for bio-agronomic traits in berseem populations (Trifolium alexandrinum L.), was evaluated. The number of genotypes was 32 (26 of southern Italy origin and 6 Egyptian). They were evaluated under field conditions for two years (1989–90) in Foggia (Italy) adopting different cutting regimes: at 7–8th inter-nodes stem length, beginning of flowering, and no cutting. The genotypes of the Italian origin appeared to be better adapted when the cut was applied in the early stage of development, and more productive in seed yield. The Egyptian populations were most productive in forage in the later cuts and had a higher seed weight. The range of variation among the bio-agronomical traits was higher when the cut was applied at early flowering. The traits with wider range of variation were: dry matter, plant height at cut, regrowth at the fourteenth day after cut, tiller density and seed yield. Considering a multiplicative selection index, 6 populations were well adapted and could be used as parents in breeding programs and in extended farm cultivation. 相似文献
14.
Piera Medeghini Bonatti Chiara Ferrari Bonaventura Focher Carmen Grippo Giangiacomo Torri Cesare Cosentino 《Euphytica》2004,140(1-2):55-64
Summary The composition and supramolecular structure of hemp primary bast fibres have been assessed using microscopy, compositional analysis, wide-angle X-ray diffractometry and CP-MAS 13C-NMR, in order to unambiguously define some quality parameters. The main components of the fibre wall were detected by histochemical reactions and modifications occurring during the plant growth have been pointed out. Some differences in fibre lignification degree were recorded among cultivars and confirmed by means of compositional and structural analysis. As for flax and kenaf, X-ray patterns revealed semicrystalline structure of hemp cellulose. NMR spectra and their probabilistic elaboration by MaxEnt method gave further insight on the presence of paracrystalline and amorphous phases and provided an accurate evaluation of polymeric components. 相似文献
15.
Sylvain Niyitanga Yi Xu Aminu Kurawa Ibrahim Lilan Zhang Shusheng Fang Jianmin Qi Liwu Zhang 《Plant Breeding》2019,138(6):897-906
Cellulose is one of the main chemical component of bast fibre in jute. However, quantitative trait loci (QTL) for bast fibre cellulose content remains elusive. In this study, we identified 846 new SSR markers from 70,792 unigenes in the NCBI and validated them in a panel of 24 diverse jute accessions. Of 846 SSRs, 748 (88.41%) were successfully amplified, and 585 (69.14%) showed polymorphisms, implying that these are high‐quality SSRs. Furthermore, 585 SSRs along with 5,074 polymorphic SLAF (specific locus amplified fragment) and 173 InDel markers were used to reconstruct a high‐dense linkage map in a recombinant inbred population with 104 F8 lines. Totally, 835 markers were successfully mapped to a whole length of 604.5 cM with a mean distance of 2.84 cM between adjacent markers. Furthermore, five QTLs for bast fibre cellulose were identified. One major QTL (qBFC1‐1) was stable in 2 years and explained average phenotypic variance with 14.34%. These results may be useful for developing enhanced bast fibre quality in white jute through marker‐assisted selection (MAS) breeding. 相似文献
16.
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
17.
This paper aims to clarify the genetic mechanism that is responsible for the accumulation of cannabigerol (CBG) in certain
phenotypes of Cannabis sativa L. CBG is the direct precursor of the cannabinoids CBD, THC and CBC. Plants strongly predominant in CBG have been found in
different fibre hemp accessions. Inbred offspring derived from one such individual were crossed with true breeding THC predominant-
and CBD predominant plants, respectively. The segregations in the cross progenies indicate that CBG accumulation is due to
the homozygous presence of a minimally functional allele, tentatively called B0, at the single locus B that normally controls the conversion of CBG into THC (allele BT) and/or CBD (allele BD). The fact that CBG accumulating plants have so far been found in European fibre hemp populations that are generally composed
of BD/BD plants, and the observation that the here investigated B0 allele possesses a residual ability to convert small amounts of CBG into CBD, make it plausible that this B0 is a mutation of normally functional BD. Therefore, B0 is considered as a member of the BD allelic series encoding a CBD synthase isoform with greatly weakened substrate affinity and/or catalytic capacity. 相似文献
18.
The usual practice of estimating association and direct and indirect effects among various traits in Gossypium hirsutum is with ungrouped genetic material based on staple length and strength. During 2003–2004 and 2004–2005 genotypic and phenotypic
association among ten characters were estimated in G. hirsutum genotypes: (i) set-1: 10 genotypes of low fibre strength (≤196.2 mN/tex) and medium staple length (≤25.0 mm), (ii) set-2:
10 genotypes of high fibre strength (≥235.44 mN/tex) and long staple length (≥28 mm) and (iii) set-3: 20 genotypes of set-1
and 2. The differences in the estimates of associations, direct and indirect effects for different characters in fibre quality
groups were examined. The complete analysis of variance for the characters under study viz; days to 50% flowering, plant height
(cm), number of monopodial and sympodial branches per plant, seed cotton yield per plant (g), boll weight (g), total number
of bolls per plant, lint %, 2.5% span length (mm) and fibre strength (mN/tex) indicated highly significant genotypic differences
for genotypes, years and genotype × years interaction. Variation within medium staple length and low strength (set-1), high
staple length and high strength genotypes (set-2) and their interaction with year were also significant. Medium staple length
and low strength (set-1) versus high staple length and high strength component (set-2) was significant for all the traits
indicating significant variability between the sets. A true relationship and direct selection were observed for days to 50%
flowering, number of monopodial and sympodial branches per plant with seed cotton yield in the three sets suggesting that
separation of genetic material based on staple length and fibre strength for improvement of seed cotton yield through these
traits is not required. Magnitude and direction of direct effect and association with yield of the other traits; plant height,
number of total bolls per plant, boll weight, lint %, staple length and fibre strength differed between the sets. This study
concluded that more successful planning of a breeding programme can be made through path coefficient analysis if the genetic
material is grouped based on staple length and fibre strength.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
19.
Summary The reliability of a selection among crosses based on a cross prediction in early generations was investigated in spring rapeseed. The performance of the parents, the F2 generation, and random F3 lines from four crosses were used to predict the probability of finding superior recombinant lines. These predictions were made for two years and compared with the observed performance of F6 lines in the second of these two years and in an additional year. Predicted and observed performances coincided reasonably for the characters plant height, standability, maturity and an index calculated from seed yield, oil content and protein content. For seed yield and flowering time, the predictions were very unreliable. In conclusion, prediction methods may be useful in rapeseed breeding, if quality traits are of major commercial interest. 相似文献
20.
Summary As the seed market for forage grasses in France is rather limited, proposed varieties should have a broad adaptation to a range of different environment. Therefore a comprehensive strategy of multisite recurrent selection has been devised for perennial reyegrass. It is based on an experimental cooperative network between National Institute for Agronomic Research (INRA) and private companies. A pragmatic approach has been retained that gives a compromise between theoretical and practical considerations. The method is illustrated by results from a breeding population consisting of 33 half-sib families derived from a local germplasm. Family selection with an intensity of 30% was applied to yield and persistence data from sward plot trials. The strategy was based on a multisite index where trait x location combinations are considered as different traits and given equal economic weights. Improvements of 10–15% were expected for summer-autumn production and persistence. For spaced plant nursery traits, a subset of locations was chosen according to a multiplicative model decomposition of G x E interaction, where a 10% mass selection was practised. This leads to interesting progress on crown rust tolerance, growth scores, leafiness and persistence. Moreover, the expected indirect responses from selection on spaced plant traits to sward traits and vice-versa are almost all favourable. As significant improvements are expected for most traits in all locations, this programme should allow to increase the general adaptation of ryegrass varieties for France. 相似文献