Identification of genomic regions associated with seed dormancy in white-grained wheat

Pre-harvest sprouting (PHS) in developing wheat (Triticum aestivum L.) spikes is stimulated by cool and wet weather and leads to a decline in grain quality. A low level of harvest-time seed dormancy is a major factor for PHS, which generally is a larger problem in white-grained as compared to red-grained wheat. We have in this study analyzed seed dormancy levels at the 92nd Zadok growth stage of spike development in a doubled-haploid (DH) white wheat population and associated variation for the trait with regions on the wheat genome. The phenotypic data was generated by growing the parent lines Argent (non-dormant) and W98616 (dormant) and 151 lines of the DH population in the field during 2002 and 2003, at two locations each year, followed by assessment of harvest-time seed dormancy by germination tests. A genetic map of 2681 cM was constructed for the population upon genotyping 90 DH lines using 361 SSR, 292 AFLP, 252 DArT and 10 EST markers. Single marker analysis of the 90 genotyped lines associated regions on chromosomes 1A, 2B, 3A, 4A, 5B, 6B, and 7A with seed dormancy in at least two out of the four trials. All seven putative quantitative trait loci (QTLs) were contributed by alleles of the dormant parent, W98616. The strongest QTLs positioned on chromosomes 1A, 3A, 4A and 7A were confirmed by interval mapping and markers at these loci have potential use in marker-assisted selection of PHS resistant white-grained wheat.     

Identification and validation of quantitative trait loci associated with seed yield in soybean

In soybean [Glycine max (L.) Merrill], the genetic analysis of seed yield is important to aid in the breeding of high-yielding cultivars. Seed yield is a complex trait, and the number of quantitative trait loci (QTL) involved in seed yield is high. The aims of this study were to identify QTL associated with seed yield and validate their effects on seed yield using near-isogenic lines. The QTL analysis was conducted using a recombinant inbred line population derived from a cross between Japanese cultivars ‘Toyoharuka’ and ‘Toyomusume’, and eight seed yield-associated QTL were identified. There were significant positive correlations between seed yield and the number of favorable alleles at QTL associated with seed yield in the recombinant inbred lines for three years. The effects of qSY8-1, a QTL promoting greater seed yield, was validated in the Toyoharuka background. In a two-year yield trial, the 100-seed weight and seed yield of Toyoharuka-NIL, the near-isogenic line having the Toyomusume allele at qSY8-1, were significantly greater than those of Toyoharuka (106% and 107%, respectively) without any change for days to flowering and maturity. Our results suggest that qSY8-1 was not associated with maturity genes, and contributed to the 100-seed weight.     

Effects of high oleic acid soybean on seed yield,protein and oil contents,and seed germination revealed by near‐isogeneic lines

Typical soybean oil is composed of palmitic, stearic, oleic, linoleic and linolenic acids. High oleic acid content in soybean seed is a key compositional trait that improves oxidative stability and increases oil functionality and shelf life. Using a marker‐assisted selection method, near‐isogenic lines (NILs) of G00‐3213 for the high oleic trait were developed and yield tested. These NILs have various combinations of FAD2‐1A and FAD2‐1B alleles that were derived from the same backcrossing populations. The results indicated that G00‐3213 NILs with both homozygous mutant FAD2‐1A and FAD2‐1B alleles produced an average of 788 g/kg oleic acid content. The results also demonstrated that possessing these mutant alleles did not cause a yield reduction. Furthermore, seed germination tests across 12 temperatures (12.8–32.0°C) showed that modified seed composition for oleic acid in general did not have a major impact on seed germination. However, there was a possible reduction in seed germination vigour when high oleic seeds are planted in cold soil. The mutant FAD2‐1A and FAD2‐1B alleles did not hinder either seed or plant development.     

Combining ability of seed vigor and seed yield in soybean

Studies have shown no consensus in relationships between seed yield and vigor in soybean [Glycine max (L.) Merrill]. The lack of information regarding the inheritance of seed vigor prompted this study to determine the types of gene action and combining ability estimates for seed vigor and its related traits. Five high and six low seed vigor soybean genotypes were crossed in a diallel, and selfed to produce 55 F₂ progenies, which were examined, along with the parents, for seed vigor, yield, and seed weight. Significant genotype and environment effects were found for seed vigor and yield. General combining ability (GCA) effects for seed vigor and seed yield were significant (p≤ 0.01) and larger than specific combining ability (SCA) effects. Significant GCA and SCA effects were found for seed weight, indicating that both additive and non additive genetic effects were involved in conditioning seed weight. The ratios of mean square, 2GCA / (2GCA+SCA), were 0.96 for seed vigor and 0.93 for seed yield. These ratios indicated that additive gene effects were more important than non additive gene effects for seed vigor and seed yield in these crosses. Mean seed vigor(83.8%), as determined by accelerated aging germination, and mean seed yield (2,155 kg ha^-1)in high vigor × high vigor crosses were higher than the high vigor × low vigor and low vigor × low vigor crosses. Mean percent accelerated aging germination rates in F₂ populations from diallel crosses were significantly related to mid-parent seed vigor(r² = 0.52^**) and midparent seed size (r² = 0.31^**). These results indicated that levels of seed vigor can be improved through breeding, while maintaining high yields because of the predominance of GCA effects in both seed vigor and seed yield. This revised version was published online in July 2006 with corrections to the Cover Date.     

Unconditional and conditional QTL underlying the genetic interrelationships between soybean seed isoflavone,and protein or oil contents

Selection for soybean (Glycine max L. Merr.) rich in isoflavones, protein and oil has been difficult due to negative genetic interrelationships. In this study, genetic interrelationships among seed isoflavones and protein and oil contents were evaluated using both unconditional and conditional QTL mapping. Daidzein (DZ), genistein (GT), glycitein (GC) and total isoflavone (TI) contents were analysed in F_5:6, F_5:7 and F_5:8 recombinant inbred lines (RILs) derived from a cross between ‘Zhongdou 27’(TI 3791 μg/g; protein content 42.84%; oil content 18.73%) and ‘Jiunong 20’ (TI 2061 μg/g; protein content 34.05%; oil content 21.42%). When DZ, GT, GC and TI were analysed for their genetic relationships with protein or oil contents, eight conditional QTL were detected, which included DZ|pro, GC|pro, GT|pro, TI|pro, DZ|oil, GC|oil, GT|oil and TI|oil. Seventeen QTL that had significant genetic associations between seed isoflavone, and seed protein or oil contents were found, including two for DZ conditioned on protein (qDZ|proK‐1, qDZ|proF‐2); one for GC conditioned on protein (qGC|proM‐1); three for GT conditioned on protein (qGT|proM‐1, qGT|proA2‐1, qGT|proL‐1); three for TI conditioned on protein (qTI|proM‐1, qTI|proA2‐1, qTI|proF‐2); one for DZ conditioned on oil (qDZ∣oil K_1); one for GC conditioned on oil (qGC∣oilI_1); four for GT conditioned on oil (qGT∣oil A2_1, qGT∣oil F_1, qGTF_2, qGT∣oilD2_1); three for TI conditioned on oil (qTI∣oilA2‐1, qTI∣oilE‐1, qTI∣oilL‐1). Few epistatic interactions among loci were detected. These loci may be valuable for improving seed isoflavone, protein and oil contents.     

Identification of quantitative trait loci associated with boiled seed hardness in soybean

Boiled seed hardness is an important factor in the processing of soybean food products such as nimame and natto. Little information is available on the genetic basis for boiled seed hardness, despite the wide variation in this trait. DNA markers linked to the gene controlling this trait should be useful in soybean breeding programs because of the difficulty of its evaluation. In this report, quantitative trait locus (QTL) analysis was performed to reveal the genetic factors associated with boiled seed hardness using a recombinant inbred line population developed from a cross between two Japanese cultivars, ‘Natto-shoryu’ and ‘Hyoukei-kuro 3’, which differ largely in boiled seed hardness, which in ‘Natto-shoryu’ is about twice that of ‘Hyoukei-kuro 3’. Two significantly stable QTLs, qHbs3-1 and qHbs6-1, were identified on chromosomes 3 and 6, for which the ‘Hyoukei-kuro 3’ alleles contribute to decrease boiled seed hardness for both QTLs. qHbs3-1 also showed significant effects in progeny of a residual heterozygous line and in a different segregating population. Given its substantial effect on boiled seed hardness, SSR markers closely linked to qHbs3-1, such as BARCSOYSSR_03_0165 and BARCSOYSSR_03_0185, could be useful for marker-assisted selection in soybean breeding.     

SCAR and RAPD markers associated with 18-carbon fatty acids in rapeseed, Brassica napus

Breeding rapeseed for enhanced oil quality includes the development of varieties with low linolenic acid content. The breeder also aims to develop varieties with a high linoleic acid content because of its nutritional value. Restriction fragment length polymorphism (RFLP) and random amplified polymorphic DNA (RAPD) markers have been developed for linolenic acid content, but they are not best suited for a direct application in marker-assisted selection. The RFLP technique is too complex and time-consuming and RAPD markers lack codominance, precluding the distinction of homozygous from heterozygous individuals. In this report the conversion of a RAPD marker to a codominant sequence characterized amplified region (SCAR) marker named L1L9 is described. One of the alleles consisting of an 899 bp fragment (allele A), is associated with low linolenic acid content. The other allele consists of an 641 bp fragment (allele B) and is associated with high linolenic acid content. This marker explains approximately 25% of the genetic variation for this trait. Linkage analysis in the mapping population indicates that the SCAR marker probably tags an ω-3 desaturase gene in B. napus. Two RAPD markers were found to be associated with oleic/linoleic acid content. Markers M14-350 and I06-650 explained approximately 10% and 7% of the genetic variation for linoleic acid content, respectively. These two markers were found linked at 12.3cM in the segregating B. napus F₂ progeny used for mapping. All the markers reported in this paper should be useful in breeding programmes for developing high linoleic and low linolenic acid rapeseed varieties.     

Quantitative trait locus analysis for soybean (Glycine max) seed protein and oil concentrations using selected breeding populations

Soybean seed protein and oil concentrations are important traits that directly affect the quality of soyfoods. Many studies and breeding programmes have been conducted to find major quantitative trait loci (QTL) that regulate protein and oil concentrations and to develop soybean cultivars with high protein and/or oil content. The purpose of this study was to identify these QTL using a selected breeding population. The population was tested in field conditions over a period of 3 years. Seed protein and oil concentrations were measured each year. Single‐nucleotide polymorphisms (SNPs) were used to construct genetic map using a 180K SoyaSNP array, which identified 1,570 SNPs. We identified 12 QTL for seed protein, 11 for seed oil concentration and four for both traits. Among these, 17 QTL were closely mapped to previously reported QTL, whereas ten sites were novel. Several QTL were detected across at least two experimental years. These loci are good candidate QTL for optimal seed protein and oil concentrations. Our results demonstrate that favourable target QTL can be successfully identified using selected breeding populations.     

高油高产抗病大豆新品种合农69选育

合农69（试验代号合交05-648）,是黑龙江省农业科学院佳木斯分院2002年以高油、高产、抗病、半矮秆耐密植品种合交98-1622（北丰11譎obbit）为母本,与丰产性好、适应性强、抗灰斑病、生产上大面积种植的品种垦丰16为父本,经有性杂交,系谱法选育而成。2014年由黑龙江省农作物品种审定委员会审定推广。该品种亚有限结荚习性,顶荚丰富,每节荚数多,三、四粒荚多,高产稳产,丰产性突出;株高稍矮,秆强耐密植;籽粒圆形,大小均匀一致,种皮金黄色,有光泽,种脐浅黄色,商品性好;脂肪含量高,属高油品种;接种鉴定抗大豆灰斑病;熟期适中,属中早熟品种;适应性广,适于黑龙江省第三积温带大面积种植和第四积温带作为搭配品种种植。     

Identification of quantitative trait loci underlying seed protein and oil contents of soybean across multi‐genetic backgrounds and environments

Seed protein and oil contents are important quantitative traits in soybean. Previously, quantitative trait loci (QTL) associated with seed protein and oil were mostly identified in single genetic background. The objective of this work was to identify QTL and their epistatic effects underlying seed protein and oil contents in three recombinant inbred line populations (two of them used one common female parent) across eight environments by composite interval mapping. Forty QTL underlying protein content and 35 QTL underlying oil content were identified. Among them, nine were universal QTL underlying protein content and four were universal QTL underlying oil content. Epistatic interactions between QTL underlying seed protein/oil and different genetic backgrounds were detected. Different pairs of epistatic interactions were observed in diverse genetic backgrounds across multi‐environments. Common marker intervals were observed to simultaneously underlie seed protein and oil contents with different epistatic interactions. The results in this study suggested that a specific genotype with high oil content and low protein content might significantly affect the selection of soybean lines for high seed protein.     

Identifying plant architectural traits associated with yield under intercropping: Implications of genotype-cropping system interactions

Increased yields of some crops have resulted from indirect selection of plant architectural traits related to yield. This study examines the potential relationship between plant architecture and yield for a legume grown under intercropping, Field experiments were conducted in 1991 to examine the response of two cowpea (Vigna unguiculata (L.) Walp.) genotypes with contrasting plant habits to sole crop and intercrop with pearl millet (Pennisetum americanum (L.) Leeke), and to identify cowpea traits associated with yield under intercropping. The cultivur with a bush-type habit was higher-yielding in sole crop, whereas the cultivar with a spreading habit was higher-yielding in intercrop. For F₂ cowpea populations, pod number was most highly correlated with seed yield in intercrop. The number of branches and nodes, particularly in areas with increased access to light, and increased internode length were also important in intercrop. Selection for improved yield in sole crop may not necessarily lead to improved yield in intercrop, and different plant traits may be more appropriate for cultivars intended for use in inter-crop than for those intended for use in sole crop.     

Impacts of erucic acid and glucosinolate content on genetic relationships between protein content and fatty acids of rape seed across environments

Impacts of erucic acid content (EAC) and glucosinolate content (GSLC) on the genetic correlations between protein content (PC) and oil content (OC) or PC and fatty acid contents (FAC) in rape seed (Brassica napus L.) was analyzed by using unconditional and conditional methods related to genetic effects from the diploid embryo nuclear genes, cytoplasm genes and diploid maternal plant nuclear genes. A diallel mating design in two environments was conducted by using eight varieties along with their F₁ and F₂. It was found that there were significant relationships between PC and EAC or PC and GSLC of rape seed, and the conditional analysis method could be used to exclude the influences of EAC or GSLC for further revealing the actual genetic relationships between PC and OC or PC and FAC. The results from conditional analysis showed that when PC was conditioned on EAC or GSLC the conditional phenotypic and genotypic relationships between PC|EAC and oleic acid content or PC|GSLC and OC were changed to significantly positive, while those between PC|EAC and eicosenoic acid content or PC|GSLC and linolenic acid content became significantly negative. Thus, the levels of EAC and GSLC of rape seed could affect the correlations between PC and OC or PC and FAC. For the conditional genetic relationship analysis of different genetic systems, visible changes were found for many genetic correlation components from the embryo, cytoplasm and maternal plant between PC and OC or PC and FAC after eliminating the influences of EAC or GSLC, especially for conditional embryo dominance, cytoplasmic, maternal additive main covariances and conditional embryo dominance interaction covariance.     

Intercropping corn with soybean,lupin and forages: yield component responses

Intercropping systems influence yield variables of the component crops, such as harvest index, hundred seed weight, number of reproductive organs and number of seeds, within each reproductive unit. Two experiments were carried out at each of two sites during 1993 and 1994. The first experiment investigated the effects of seeding soybean or lupin alone or in combination with one of three forages (annual ryegrass, Lolium multiflorum Lam.; perennial ryegrass, Lolium perenne L.; red clover, Trifolium pratense L.) with corn on the yield components of corn, soybean and lupin. The second experiment examined the effects of seeding date (simultaneous with corn or 3 weeks later) and number of rows of large seeded legumes (one or two) seeded between the corn rows. Corn grain yield was generally not affected by any intercrop treatment, although in 1993 some simultaneously seeded treatments resulted in decreased yields. Soybean grain yield was decreased by most treatments, although some simultaneous seedings produced yields similar to soybean monocrops. Lupin grew poorly as an intercrop component, producing little or no grain. Corn harvest index was not affected by any intercrop treatments. Seeding corn and large-seeded legumes simultaneously resulted in decreases in corn hundred seed weights by as much as 6.6 g compared with the monocropped corn. In 1993 (a year with normal precipitation levels), the hundred seed weight and number of seeds per soybean pod were decreased by intercropping, although the harvest index was not affected. In a high precipitation year (1994), the soybean harvest index was decreased by intercropping, but not the seed components. The underseeded forages, annual ryegrass, perennial ryegrass and red clover, had no effect on yields or yield components of the other intercropped species.     

高油抗SCN3大豆新品种齐农1号的选育

齐农1号是黑龙江省农业科学院齐齐哈尔分院于2002年以嫩950127-4?东农42的F1为母本,与以嫩丰16为父本,进行有性杂交选育而成的大豆新品种。该品种适应性广,稳产丰产性好,2年区域试验10点次试验全部增产,平均公顷产量 2656.0 kg,平均比对照品种嫩丰18 号增产14.1%,一年生产试验,5点次试验全部增产,平均公顷产量 2281.9 kg,平均比对照品种嫩丰18号增产12.4%;蛋白质含量为40.46 %,脂肪含量为21.53%,中抗大豆孢囊线虫3号生理小种,适宜黑龙江省第三积温带上限种植。2013年通过黑龙江省农作物品种审定委员会审定推广应用种植,是一个稳产、抗线性状较为突出的高油大豆新品种。     

Pure line selection for improved yield, oil content and different fatty acid composition of sesame, Sesamum indicum

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.     

Relationships between seed oil content and fatty acid composition in high stearic acid sunflower

The high stearic acid sunflower mutant CAS-3 is characterized by a low seed oil content, which might represent a constraint for the commercial production of high stearic acid sunflower oil. The objective of the present research was to investigate the relationships between fatty acid profile and seed oil content in CAS-3. Plants of CAS-3 were reciprocally crossed with plants of breeding line ADV-37, with high oil content and standard fatty acid profile. Oil content and fatty acid composition were measured in individual F₂ seeds and F₂ plants (F₃ seeds averaged). Both F₂ seeds and F₂ plants from the cross ADV-37 × CAS-3 had a significantly higher oil content than those from the reciprocal cross, which indicated the existence of cytoplasmic effects in the genetic control of the trait. A consistent negative correlation between oil content and palmitic acid and a positive correlation between oil content and oleic acid were detected both in F₂ seeds and F₂ plants. Conversely, no consistent correlation between oil content and stearic acid was observed, which suggested the feasibility of simultaneous selection for both traits.