Wuhan 430062, China; 2. School of Life Sciences, Hubei University, Wuhan 430062, China; 3. Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei University, Wuhan 430062, China)
Abstract: To increase the efficiency of molecular marker-assisted selection on plant height and ideotype, data from 3 environments were collected using recombination inbred lines (RILs) population of Brassica napus, and genotypic data from 7 877 SNPs were investigated for genome-wide association. 5 significant SNPs (Bn-scaff_15794_3-p62430, Bn-A02-p9599263, Bn-A02-p9409799, Bn-A02-p9993945 and Bn-A02-p9636219) for plant height had been identified in at least 2 environments. They were located on A02 chromosome. Compared to QTL linkage analysis, the markers (Bn-A02-p9599263 and Bn-scaff_15794_3-p62430) respectively located on the peak of QTL qPH2-2 and qPH2-4. Markers Bn-A02-p9636219 and Bn-A02-p9993945 were located in 2-LOD (log of the likehood odds ration) confidence interval for QTLs qPH2-3 and qPH2-4. Bn-A02-p9409799 was found near distance of 0.3 cM confidence interval QTL (qPH2-2). The interval range of QTL by genome-wide association studies (69.5-80.7 cM) was 24 cM shorter than that by QTL linkage analysis (60.7-95.9 cM). According to the reference genome annotation information, a candidate gene (GSBRNA2T00090973001) corresponding to the significant SNP (Bn-scaff_15794_3-p62430) was predicted, locating in 2 kb away from the SNP. These results indicated that using single RIL population for gene-wide association studies not only compensated QTL's linkage results, but also provided theoretical basis for fine mapping and gene cloning.
To gain more information of the cytological of Tibetan yellow-seed rape (Brassica rapa L.), 8 yellow-seed rape landraces from Tibet China were selected and performed by tabletting observation based on karyotypic parameters. Results showed that each material had 20 chromosomes composed by median region chromosomes (m) and sub-median region chromosomes (sm) with a pair of satellites. Their karyotype belonged to 2A type. Their chromosome morphology was different. The differences included Lt/St (1.60-1.91) (with average arm ratio of 1.33-1.52) and asymmetry index from 56.08% to 58.85%. According to karyotype dissymmetry coefficient, their evolution degree showed that Taba Monastery yellow-seed was the highest, and Xialu Monastery yellow-seed was the lowest. 8 landraces could be divided into 3 groups by karyotype features. Evolution and cluster analysis results showed that the evolutionary rate of yellow-seed rape landraces from Tibet was slow. These landraces were still at their original evolutionary stage.
Downy mildew of Brassica napus, caused by the oomycete Hyaloperonospora parasitica, is an important disease during the epidemic. In this study, F2 population derived from a susceptible-parent and resistant-parent was used to construct resistant and susceptible pools. In order to obtain molecular markers related to disease resistance to downy mildew, BSA and SLAF-seq technique were developed. Firstly, reference genome of B. napus was used to design marker discovery experiments in silico by simulating the number of markers produced by different enzymes. Secondly, the SLAF library was conducted and sequenced by paired-end sequencing. 132 519 SLAF labels were obtained and 264 256 SNPs were found. Thirdly, the associated region was located by SNP-index, and the SNPs locating at the associated region were analyzed between the two parents. After annotation, 2 non-synonymous -coding SNPs were found. By verification, these SNPs were considered to be related to resistance to downy mildew and were genetically stable. Finally, 2 specific primer pairs for each SNP were obtained by SNAPER software which designed primers generated differences in the amplification products.
pAccording to the location of SSR primers in genetic linkage map, 200 pairs of primers were selected with uniform distribution on the chromosome. Then, through olyacrylamide gel electrophoresis and silver stain technology, 120 primers were chosen with clear bands and repeating. Finally, using capillary electrophoresis technology to screen, primers with uniform distribution on the chromosome were selected with the alleles number more than 4, and polymorphism information content (PIC) value higher than 0.4, and heterozygosity being lower than 0.1 primers. 60 of primers were selected to identify fingerprint of peanut cultivars as core primers, which had abundant polymorphism, broad representative and uniform distribution of genome, with good amplification effect in both common primers and fluorescent primers. Among 60 core primers, 352 polymorphic alleles were amplified in 100 peanut varieties with the average polymorphic alleles being 5.87, and the average number of genotypes distinguished being 6.35, and the mean PIC being 0.54. Primers accounted for 66.67% with high polymorphism primers, and heterozygosity was below 0.06. The genetic similarity coefficient among cultivars ranged from 0.530 to 0.683. Fingerprint establishment of 100 peanut varieties provided a foundation for the construction of DNA fingerprint database of peanut varieties and resources.
Heat shock protein 70 is a kind of molecular chaperones. They play an important role in cell responses to stresses. In this study, genome identification and analysis of Hsp70 gene family members in Arachis duranensis and Arachis ipaënsis were performed using bioinformatic methods. The results showed that A. duranensis contained 34 Hsp70 genes, and A. ipaënsis contained 35 Hsp70 genes. The orthologous gene pairs located at the similar position in A. duranensis and A. ipaënsis. AdHsp70 and AiHsp70 family genes were classified into 3 types based on their sub-cellular locations, and the gene structures were relatively conserved in each type. AdHsp70 and AiHsp70 family genes were divided into ClassⅠ (Hsp70) subfamily and ClassⅡ（Hsp110） subfamily base on evolutionary analysis, and ClassⅠ subfamily was further divided into 3 small families. Evolutionary analysis of Hsp70s in diverse species revealed that Hsp70 gene families occurred before the monocot and dicot differentiation. GO analysis showed a complete consistency between the function category of AdHsp70 gene family and AiHsp70 gene family, and the changes of function category proportion were similar. This study provided the complete profiles of Genus Arachis Hsp70 gene family for future study on their functions related to the molecular mechanisms of stress physiology.
SUMO is an ubiquitin like peptide that binds to the target protein after translation. The sumoylation in plant has demonstrated an important role for the process in growth and development, stress response such as heat shock, flowering control and pathogen defense. In this study, soybean SUMO related gene and protein structure were analyzed by bioinformatics tools. The phylogenetic tree showed that most of soybean SUMO related genes were closely relatedly to woody plants, which indicated that soybean SUMO related genes(GmSUMO,GmSAE1,GmSCE,GmE3f) evolved from woody plant. 6 genes in SUMO (GmSUMO2, GmSUMO3, GmSAE1b, GmSCEb, GmE3f, and GmESD4d) were analyzed by real-time PCR. With 0 to 30 minute heat shock treatment, the gene expression of 6 soybean SUMO genes showed obvious change, GmSAE1b first starts. After 10 min, relative expression level of GmSUMO2/3 reached the minimum. However, relative expression level of GmESD4d raised nearly 40 fold in leaf, which might play a major role of desumoylation in leaf. Then, 30 mins after heat shock, relative expression level of GmSUMO2 increased nearly 27 times, GmSCEb 10 times, GmE3f nearly 40 times in root, which showed that GmSUMO2, GmSCEb and GmE3f mainly functioned in the root.
In national winter rapeseed region of the Yangtze River Basin, rapeseed plantlets regenerated from microspore culture had to pass the long and hot summer season. At present, multiple subculture technique was used as common practice with cumbersome procedure, high requirement of technology and had high risk of microbe contamination. Features of the present technique severely restricted the development of microspore culture. To improve the technique, we modified hydroponics methods prompting rapeseed microspore plantlets to pass the summer. The hydroponics obtained more than 90% survivals of rapeseed plantlets and more than 93% survivals of field-transplanted seedlings. In economy, this technology saved more than 90% chemical reagents and labor costs. It simplified the over-summer operational process greatly.
Exploring the accumulation patterns of salt-related cations in rapeseed would benefit in discovering salt tolerance mechanisms of this important oilcrop. In this study, two rapeseed genotypes (tolerant WH126 and sensitive WH137) were treated with gradient concentration of NaCl solutions at seedling stage. Results indicated that shoots and roots dry weight of sensitive line WH137 decreased more than those of tolerant WH126. Four cations (Na+, K+, Ca2+ and Mg2+) accumulations showed that Na+ in shoots and roots presented a rising trend and contents of the other three ions (K+, Ca2+ and Mg2+) had down-trend with the increase of NaCl concentration. Compared with WH137, WH126 had less increase of Na+ in shoots and roots and had less decease of K+ in shoots under salt stress. No difference on the variations of Ca2+ and Mg2+ accumulations in neither shoots nor roots. Changes of K+/Na+, Ca2+/Na+ and Mg2+/Na+ ratios were not correlated to salt tolerance of rapeseed. Therefore, results demonstrated that the mechanism of ‘preventing entry of Na+ and retaining K+’ might be one of the major reasons for their discrepancy in rapeseed salt tolerance.
To better understand waterlogging response of sesame during full flowering stage, pot experiments were conducted by using 2 cultivars (sensitive Zhengzhi 13 and high tolerant Zhengzhi 98N09). Sesame dry matter accumulation and distribution were investigated under different durations. The treatments included flooding for 12 h (W12h), 24 h (W24h) and 36 h (W36h). Result showed that dry matter weight in both cultivars decreased with the treatment durations. Moreover, larger differences of dry matter were showed at longer treatments. From full flowering to harvest, the distribution ratio of dry matter decreased in stems and leaves, but increased in capsules. At final flowering and harvest stages, yield and other agronomic traits decrease with the durations, which including plant capsules, capsule grains, 1 000-grains. Their decrease among each treatment was statistically significant. Logistics model fitted the dynamic of dry matter accumulation well with the determination coefficient above 0.99. Maximum accumulation rates (Rmax) of the 2 cultivars were decreased with waterlogging durations, and the time of maximum accumulation rate (Tmax) were shortened. Accumulation rate in fast-increase period (R2) and slow-increase period (R3) decreased with increasing waterlogging duration, while duration of fast-increase period (T2) and slow-increase period (T3) increased. Between the 2 cultivars, Tmax, Rmax, T2, R2, R3 of Zhengzhi 13 were lower, but only T3 were higher. The fast-increase period (T2) would last from 46.44 to 64.79 d after emergence, which was the same duration of time from full flowering to final flowering stages. Simulated results showed that dry matter dynamic accumulation was closely related to yield formation under waterlogging in full flowering stage. The dry matter increased sharply from full flowering to final flowering. The difference of dry matter accumulation was mainly due to the difference of T2 and R2 between sensitive and tolerant cultivars.
Soybean cultivar Beidou 44 seedlings were used as test materials in pod experiment, to study the effects of exogenous abscisic acid (ABA) and brassinolide (BR) on drought resistance of soybean. The results showed that with the normal water supply, BR inhibited the photosynthesis of seedling, ABA promoted stomatal closure, and decreased intercellular CO2 concentration, BR enhanced the effect of ABA. Under drought stress, high concentrations of BR (0.4 mg/L) accelerated the damage of seedling caused by drought, but ABA relieved the damage severity; low concentration of BR increased chlorophyll content, ABA could alleviate the effect of BR on chlorophyll; BR (0.2, 0.4 mg/L) reduced the influence on soybean photosynthesis under drought. The combination of ABA and BR showed greater effect on photosynthesis in soybean; BR reduced the promotional effect of stomatal closure caused by ABA, and increased Fv/Fm and ФPSII in PSII reaction center, which were consistent with the effect on photosynthesis. Therefore the interaction of ABA (2 mg/L) and BR (0.2 and 0.4 mg/L) made greater contribution to drought resistance of soybean. In conclusion, appropriate concentration of ABA and BR could effectively alleviate the drought stress, and maintain the normal metabolism of soybean.
In order to clarify the physiological role of S3307 in reducing the damage of soybean flooding stress, effects of uniconazole on leaf photosynthetic characteristics and yield of soybean under waterlogging stress were studied. A pot experiment with 2 soybean varieties Kenfeng 14 (waterlogging-tolerant) and Kenfeng 16 (waterlogging-sensitive) was conducted，and leaf photosynthetic characteristics were determined in V3, V3-3d (flooding 3d), V3-5d (flooding 5d), and normal water conditions (R1, R3, R5), to analyze the regulation effect of spraying uniconazole on the relative chlorophyll content, photosynthetic indexes, and yield per plant under waterlogging stress. The results showed that reduction of leaf net photosynthetic rate (Pn), transpiration rate (E), stomatal conductance (C) and intercellular CO2 concentration (Ci) in Kenfeng 16 were greater than those of Kenfeng 14 during waterlogging stress period (V3-3d to V3-5d); leaf Pn in Kenfeng 14 increased significantly in comparison to Kenfeng 16 under normal water conditions. Compared with spraying water under waterlogging, uniconazole could improve the leaf Pn, E, C and Ci under waterlogging stress. Moreover, leaf SPAD, photosynthetic indexes in uniconazole were higher than those with normal water (CK) treatment. The yield per plant of Kenfeng 14 in uniconazole under waterlogging stress was increased by 105.81% and 28.17%, compared with spraying water under waterlogging stress and CK respectively; the increases were 10.16% and 23.93% in Kenfeng 16. Therefore, spraying uniconazole improved the leaf photosynthetic characteristic, resulting in higher yield per plant under waterlogging stress, but the sensitivity of different soybean varieties was different.
: For reasonable fertilization of oil flax on dry land (on hilly area of the loess plateau), the effect of nitrogen-phosphorous combination on phosphorus utilization was investigated by using cultivar Longyaza 1. Four fertilizer treatments were designed: 2 for nitrogen (N1: 75 kg·hm-2 and N2: 150 kg·hm-2) and 2 for phosphorus (P1: 75 kg·hm-2 and P2: 150 kg·hm-2). Their combinations were coded as N1P1, N1P2, N2P1 and N2P2. N0P0 was the control without additional nitrogen and phosphorous. Results showed that the trends of phosphorus uptake at different growth stages were similar. Phosphorus absorption of oil flax reached top level during anthesis to maturity. Leaf was the main organs for phosphorus transformation. 25.03% to 72.52% more phosphorus, a significantly higher level were translocated under N2P1. 38.07% to 51.88% of grains phosphorus accumulation were transferred by leaves. Especially under N2P1, 36.28% more phosphorus were translocated from leaves to leaves. Grains obtained the most phosphorus (40.11%-45.86%) followed by stem (31.34%-36.36%). Compared to N0P0, grain yields under N1P1, N1P2, N2P1 and N2P2 were significantly enhanced by 18.95%, 32.26%, 50.41% and 38.29% respectively. The maximum phosphorus harvest index, phosphorus agronomic efficiency and phosphorus apparent use efficiency were 45.86%, 6.54 kg·kg-1 and 21.51% respectively under N2P1. Based on synthesized grain yield and phosphorus utilization efficiency, the optimal nitrogen and phosphorus application rate for oil flax was 150 kg·hm-2 (N) and 75 kg·hm-2 (P2O5) on hilly area of the loess plateau.
Clubroot disease caused by Plasmodiophora brassicae became serious in winter rapeseed production in China. To identify pathotypes of different isolates and to evaluate resistance of rapeseed resources, 16 isolates of P. brassicae from 8 provinces were identified with Williams differential hosts in green house. Results indicated 9 isolates from Anhui (Xiuning, Yixian and Guangde), Sichuan (Guanghan, Meixian and Qionglai), Hubei (Shayang, Dangyang) and Guizhou (Jinsha) belonged to pathotype 4. The other 4 isolates from Anhui (Ningguo), Yunnan (Chuxiong), Hunan (Taojiang), Liaoning (Shenyang) and Heilongjiang (Aching) belonged to pathotype 2. Isolates from Anhui (Jixi) belonged to pathotype 5 and those from Hubei (Huangpi) belonged to pathotype 7. In artificial climate chamber, 12 resistant lines were respectively inoculated by 7 isolates. Results showed that all 12 resistant lines had different resistant degree to 3 pathotypes (2, 4 and 5). Resistant line CR5 was immune to 6 isolates from Anhui and Sichuan provinces. In field disease nursery (using pathotype 4), 176 rapeseed cultivars were evaluated. Among them, Zhongdouyou 998 and Rongyou 9 had resistance (R), and 11 cultivars had moderate resistance (MR) to pathotype 4.
Key words: Plasmodiophora brassicae; Rapeseed; Pathotype; Resistance; Variety resource
To survey the damage of peanut field by Holotrichia diomphalia Bates and to development an economic threshold for pest management in Shenyang district, the third instar of H. diomphalia larvae with different population dendsity were inoculated in the peanut field, and the relationship between peanut yield and density of larvae was investigated.The results showed that the peanut yields gradually decreased with the increased population density of grubs. Their linear euqation was y﹦−8.315x+417.87 with the correlation coefficient of 0.996, which showed significant differences, y was the yield of peanut, x represented the population density. With each grub added, the yield loss was 8.315g and the yield loss rate was 1.99%. The economic threshold of the third instar of H. diomphalia lavae in the peanut field was 1.98 heads per square meter around Shenyang district.
Field trials were conducted to evaluate the efficiency of 3 new fungicides for control peanut leaf spot diseases with carbendazim as control in Shijiazhuang, Xiangyang and Hefei in 2015. The results showed that peanut leaf spot diseases occurred seriously in these sites in 2015. Peanut leaf spot diseases developed slower in fungicide treated plots than their water control in these sites. Application of 55% flusilazole•carbendazim and 20% SYP-1620•tebuconazole produced 21% and 1% higher control effect, 13% and 9% higher pod yield, 15% and 10% higher kernel yield than that of 50% carbendazim in Shijiazhuang. Application of 55% flusilazole•carbendazim, 70% metiram and 20% SYP-1620?tebuconazole showed 10%-34% higher control effect, 9%-17% higher pod yield and 9%-18% higher kernel yield than that of 50% carbendazim in Xiangyang. Application of 55% flusilazole•carbendazim, 70% metiram and 20% SYP-1620?tebuconazole had 6%-10% higher control effect, but less pod and kernel yield than carbendazim in Hefei.
To identify wild bacteria with high yield of eicosapentaenoic acid (EPA), gas chromatography and 2,3,5-triphenyltetrazolium chloride (TTC) methods were used to select 176 strains from the Arctic area. Four EPA-producing bacteria strains were obtained and further confirmed by gas chromatography and mass spectrometry (GC-MS). Among them, strain 6-42 had the highest EPA content (up to 4.9% of total fatty acids) which was identified as Shewanella baltica by 16S rDNA sequencing. The strain was named as S. baltica 6-42. Temperature and cerulenin effects were investigated. Results showed that in 3 μg/mL cerulenin at 0℃,? the EPA content and EPA titer of S. baltica 6-42 reached 11.5% and 6.7 mg/g respectively. When cultured at 10℃ with shaking, 3.6 mg/L EPA were yielded.
A multi-component immunoaffinity column (MIAC) were prepared by covalently coupling 4 high specific monoclonal antibodies, such as anti-aflatoxin (AFT, including AFB1, AFB2, AFG1, AFG2), anti-zearalennone toxin (ZEA), anti-T-2 toxin and anti-fumonisin B1 toxin (FB1), with CNBr-activated Crystarose 4B, after the investigation of 3 carriers and 2 coupling methods. In addition, with the optimization of extraction solvent, extraction method and loading condition, a method of high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) combined with self-made MIAC was established for simultaneous and quantitative determination of these 7 major mycotoxins in vegetable oil. The linear ranges of regression equation were greater and the correlation coefficients were higher than 0.992. The limits of detection to AFB1, AFB2, AFG1 and AFG2 were 0.02-0.08μg/kg and ZEA, T-2 and FB1 were 0.10-0.50μg/kg respectively. The recoveries of these 7 mycotoxins in spiked vegetable oil samples were in the range of 80.22%-106.10% with the relative standard deviation of 1.05%-6.56%. The method had the advantages of simple operation, effective purification, high recovery rate and less organic solvent consumption, which provided an efficient, accurate and sensitive technique of multi-component determination for mycotoxins in edible vegetable oil.
To develop a rapid determination method for sucrose content of peanut seed kernel, the near infrared spectrums of 72 high quality edible peanut germplasm at home and abroad were collected with Perten DA7200 NIR spectrometer, and a NIR calibration model was established by partial least squares method (modified PLS). The results showed that this model showed a high calibration coefficient of 0.822 and a small standard error of calibration of 0.386, which could replace chemical analysis to determine sucrose content.
To better use the specific oil species of almond, comparison study was performed for cold pressed oil extracted from 8 almond cultivars from Xinjiang region. The chemical composition, fatty acid, antioxidant properties (total phenol, phytosterol, Vitamin E), thermal stability (IP value and DSC) and flavor properties of the oils were determined. Results showed that SC-18 and SC-Zhipi had higher content of total fat and amino acid than others. Oleic acid exceeded 70% in SC-9, SC-Zhipi, SC-Taxi and SC-Huang cultivars. Three cultivars (SC-9, SC-Zhipi, SC-Taxi) had more than 6 types of tocopherol and tocotrienols, and were the top three in phytosterol content among all cultivars. They had longer IP time and thermal oxidation temperature than others. The key flavor of almond oil mainly included hexanal, benzaldehyde, benzeneacetaldehyde, nonanal, vanillin 2,4-decadienal, (E,E)-, phenylethyl alcohol, hexanoic acid, estragole. In summary, almond oils produced from SC-9, SC-Zhipi and SC-Taxi had better quality including nutrition, oxidation stability and flavor quality. Thus，those three cultivars were suitable for cold pressed process.
Plant root architecture, the 3-dimensional (3D) distribution of different root types in soil, is a key feature for plant to acquire environmental resources like mineral nutrients and water, especially under limiting conditions. Increasing attention was on methodology research and resulted in substantial progress in describing and quantifying root system. The advances on phenotype root system had been briefly summarized in this paper, with a special focus on a novel high throughput root architecture quantification and 3D reconstruction system (root 3D system). Oilseed rape is an important oil crop with a fine dense root system difficult to quantify. Accordingly, improvements had been made for oilseed rape on root 3D system from root growth to imaging system, which allowed greater image sensitivity, higher efficiency, and a broad array of growing conditions. The performance of the updated root 3D system had been evaluated and proved to be highly reliable. To illustrate the use of this root 3D system, the growth dynamic of oilseed rape root was quantified. Further improvement for the system was also discussed.
The achievements in novel germplasm development of Brassica napus in China are reviewed. As an important oil crop, B. napus was introduced into China during 1930s and 1940s, and was started to be cultivated widely during 1960s and 1970s when replacing native species of B. rapa and B. juncea. Bottleneck of narrow genetic diversity obstructed the breeding of B. napus in China. For their wide variations of B. rapa and B. juncea, these two species became potential sources for B. napus genetic improvement by artificial synthesis and interspecific cross. During the last decades, the interspecies hybrids of B. napus with B. rapa and B. juncea were extensively made. Elite germplasm sources and cultivars were selected and used as core parents in breeding programs. The hybrids included ‘Zhongyou 821’, and lines with yellow seeds, resistances to stem rot and club root. By tissue culture and somatic fusion, many sexual and somatic intergenetic hybrids of B. napus from other relative species were produced. Subsequent alien additions, substitutions, translocations and introgressions were obtained. Particularly, novel cytoplasmic male sterile lines were produced by mitochondrial DNA recombination during somatic fusion, and restoration lines were selected by introgressing the related restoration genes from alien chromosome.
Peanut is a major oil crop and an important economical crop in China. Drought is one of the most important environmental stresses affecting the productivity and quality of peanut. The paper analyzed the regulation dynamics of peanut growth and metabolic physiology, concluded the changes of peanut quality, and summarized the response of peanut water use efficiency to water stress and re-water. Elucidation of the complex mechanism will provide a theoretical basis for further implement of peanut water-saving cultivation techniques and choice of peanut deficit irrigation regime.
