Key enzyme of SA (salicylic acid) synthesis is isochorismate synthase 1 (ICS1). To better understand the function of this enzyme gene in Brassica napus against infection by Sclerotinia sclerotiorum, cDNA of BnICS1 was cloned based on homologous sequence in B. rapa. The complete open reading frame of BnICS1 is 1 719 bp long, encoding 572 amino acids with a predicted chorismate-bind domain. Real-time RT-PCR showed that BnICS1 expression increased at 6hpi (hours post-inoculation), but decreased after 24hpi. SA signaling pathway genes were induced. MPK4 expression decreased at 6hpi, but increased after 24hpi. These revealed that SA synthesis was induced by S. sclerotiorum at the beginning, but suppressed after necrotic lesions appeared. Expressions of EDS5 and PR1 were increased from 6hpi, and PDF1.2 was decreased after inoculation. Results indicated that SA signaling pathway eventually led to necrotic lesions, while jasmonic acid pathway was inhibited.
To adapt to machine harvesting, pod shatter resistance of oilseed rape is essential. To better understand the resistance genetics, a 726 bp open reading frame (ORF) of BnFUL coding 241 amino acids was cloned from a pod shatter resistant line R1-1 (Brassica napus) based on genome sequence of AtFUL in Arabidopsis thaliana. The deduced BnFUL protein contained a typical MADS-box and K-box conserved domain. Multiple sequence alignments showed that FUL protein sequences from different species were highly conserved within Cruciferae family, especially in MADS-box and K-box domains. Sequence variation of FUL homologs mainly occurred at 3′-end in Cruciferae. Ectopic expression of BnFUL in Arabidopsis thaliana resulted in pleiotropic phenotypes, including elevated resistance to pod shattering, earlier flowering and single peduncle with 3 siliques. These demonstrated that BnFUL gene controlled flower and fruit development in oilseed rape.
To explore the role of chalcone synthase (CHS) gene in stress tolerance mechanism of sunflower, a full-length cDNA of CHS (LSK-2) was cloned based on Helianthus annuus transcriptome induced by Sclerotinia sclerotiorum. Sequence analysis showed that HaCHS (GenBank No. KR921882) cDNA contained 1 197bp ORF encoding a protein of 398 amino acids residues with molecular mass of 43.54kDa and theoretical pI of 6.17. HaCHS protein contained 3 conserved active sites (C167, H306 and N339) and a family signature sequence of GVLFGFGPGL. Phylogenetic analysis revealed that HaCHS shared 93%-94% identities with CHS proteins of Dahlia pinnata, Rudbeckia hirta and Ageratina adenophora in Asteraceae. qRT-PCR results showed that HaCHS was highly expressed in flower, much more than in sunflower root. Its expression was significantly regulated by S. sclerotiorum, wounding, 4℃ chilling and Jasmonic acid (JA), but not by salicylic acid (SA) and abscisic acid (ABA).
Agrobacterium tumefaciens-mediated transformation of soybean is highly genotype-dependent, which strongly limits the effective progress for transformation. In this study, 13 elite soybean varieties from different producing regions were selected for comparison of their shoot induction, shoot elongation and transformation efficiency. The results showed that there were apparent varietal variation in shoot induction and significant differences in shoot elongation efficiencies after Agrobacterium infection and glufosinate screening, which led to large varietals variation of transformation efficiency. Transgenic plants were obtained from 7 out of 14 varieties, with the transformation efficiency over 2% in 4 varieties. Zhonghuang 42, a high protein variety, possessed the highest transformation efficiency of 4.1%, which can be used as a receptor material in transgenic soybean breeding in the future.
Hybrid seed production requires the removal of 50% fertile plants by using recessive genic male sterile (RGMS) two-line system (dual purpose line, AB line), which limited its utilization for sesame hybrid production. To simplify the seed production, different sesame germplasm were used as pollen donors to testcross with sterile plants (0176A) from RGMS 0176AB line. A large number of fertile plants were then selected from testcrossing separation generation with more than 60% sterile plant. Those fertile plants were paired crossed with 0176A again. Meanwhile, the male parents of fertile plants were self-fertilized for increased percentage of male sterile plants. After 13 years of testcross, self-cross, multiple generation systemic selection, relocation propagation, identification and gene polymerization, new bred lines WB51220 (maintainer), WB7-1D (maintainer), W0176A (highly sterile) and W71A (complete sterile) were obtained. Genetic tests showed that genotype of maintainer WB7-1D was msms + rf1rf1 rf2rf2…rfirfi. By using the new bred sterile and maintainer lines, new cultivars Wanzhi 6 (W0176A×Wanzhi 1 F1) and Wanzhi 11 (W71A×Wanzhi 2181 F1) were bred. The 2 cultivars had 8.27% and 23.0% higher yield than Yuzhi 4 (CK) respectively.
Maturity group (MG) is a widely-used system for soybean varieties classification in the world．For better introduction in the regions, MG of 23 varieties (lines) were categorized. The collected materials were mainly from the cultivars, and the newly bred varieties (lines) of Guizhou Province, and the introduced varieties (lines) as well as 27 MGⅠ-MGⅧ standard varieties introduced from the North America. The MG of 23 materials ranged from MGⅡto MG Ⅴ according to the tested results in 2011 to 2014. Four-year results showed that Qiandou 4, Qiandou 1, Zhonghuang 30 and Zhongdou 40 belonged to MGⅡ; Qiandou 3 and Qiandou 5 belonged to MGⅢ; Andou 5, Dian 86-5, Qiandou 2, Qiandou 6, Qiandou 7, Qiandou 8, Qiandou 08002, Andou 7, Youchun 06-8, Guichun 8, Xudou 9, Tianlong 1, Zhonghuang 50, Zhonghuang 48, Zhonghuang 42, Zhonghuang 39 and Qiandou 08014 belonged to MGⅣ; Diandou 7 belonged to MGⅤ. Most of the tested materials belonged to MG Ⅳ, and the classification criterion was clear. Varieties belonged to MGⅡ and MGⅢ were indistinct classification because that the borders of MGⅡand MGⅢ was not specific. The results of this experiment could provide a reference for the scientific classification of soybean maturity group in China and provide a basic understanding for varieties introduction in different regions.
GGE-biplot was used to analyze yield data of Heyou peanut tested in 7 sites including Ganzhou, Quanzhou, Zhanjiang, Luoding, Hezhou, Guiping, Wuxuan in southeast China. The results showed that Heyou 11 and Heyou 12 had higher yield ability and stability than other Heyou cultivars. Average yield and the highest yield of Heyou 11 were 3 510.7 kg?hm-2 and 4 447.5kg?hm-2¬, and those for Heyou 12 were 3 440.2 and 4 575.0kg·hm-2 respectively. Both Heyou 11 and Heyou 12 adapted to most sites tested, except Heyou 12 in Hezhou. The rest of cultivars had their own special adaptive regions. Heyou 9 was most suitable for planting in Hezhou, Heyou 10 in Luoding Guangdong, Heyou 13 in Zhanjiang Guangdong and Ganzhou Jiangxi, respectively. Their yields were higher than 3 410.0 kg·hm-2 in their adapted regions. GGE-biplot method could provide a guideline on cultivar breeding and yield evaluation at different conditions, and this study could contribute to peanut expansion and peanut breeding of Heyou improvement.
For effective pollen storage for Camellia germplasm, 3 camellia species were studied by anther cryopreservation in liquid nitrogen (LN) and water bath thawing. The 3 species were C. sasanqua, C. yuhsienensis Hu and C. polyodonta How. Results showed that desiccation duration and pre-chill method had significant effects on pollen germination after cryopreservation. Data indicated that after LN treatment, anthers of C. sasanqua which dried at 30℃ for 4h when anther water content reached 26.92% had the highest viable pollen. Anthers of C. yuhsienensis Hu which dried at 30℃ for 2-4h when anther water content reached 27.52%-33.71% had the highest pollen germination rate. Anthers of C. polyodonta How which dried at 30℃ for 1-3h when anther water content reached 20.98%-37.95% had the highest viable pollen than other drying treatments. Pre-chilled at -26℃(for 1h) could significantly increase the viability of pollen stored in liquid nitrogen. Rapid thawing with 38℃ hot water for 2min was the best method for pollen preservation and recover. Compared to room temperature conservation, fresh pollen of the 3 anthers lost their viability within 20-40d, while cryopreserved anthers still kept their higher germination rate after half a year, even which was relatively higher than that of fresh pollen in C. yuhsienensis Hu.
To simplify rapeseed cultivation, yield formation and N accumulation and translocation under different planting patterns, 5 patterns of A-E were used for this study. A: ridging and seedling-set by machine with rice straw returning to soil. B: ridging and seedling-set by machine without rice straw. C: manual-digging-hole transplanting with rice straw returning to soil. D: manual-digging hole transplanting without rice straw. E: direct-sowing. Traits of cultivar Suyou 6 including yield, dry matter accumulation, N accumulation and translocation were investigated. Results showed that yield under pattern A was significantly higher than those under manual-digging-hole transplanting and direct-sowing. Yield increases under ridging and seedling-set by machine were mainly resulted from significantly increased pods per plant and seeds per pod. Yield under all-rice-straw-returning to soil and no-rice-straw-returning had no significant difference. Dry matter accumulation under pattern A was the highest, with the order of A (and B)> C (and D)> E. Difference of the accumulation grew with the seedling development. Significant difference was found on N accumulation and translocation under different patterns. During the periods of early-to-end flowering and end flowering to maturity, N accumulation order was A>B>C>D>E. Compared to direct-sowing (E), the 2 transplanting methods (A and B) significantly increased N translocation of stem and leaf after flowering. But stem N translocation and contribution were lower than those of E. In summary, both ridging-and-seedling-set-by-machine (A and B) methods significantly increased dry matter production of rapeseed, N accumulation and translocation after flowering, which further improved rapeseed yield.
To understand photosynthetic characteristics and their relationship with yield of soybean, 9 soybean cultivars derived from the same ancestor parents (Williams and Amsoy), 4 from Ohio, 5 from Liaoning, were studied at different growth stages. Results showed that the trends of photosynthetic traits of soybean cultivars from Liaoning and Ohio were consistent during program of seed yield improvements. Leaf area index, leaf greenness (SPAD), net photosynthetic rate (Pn), stomata conductance (Gs) and transpiration rate (Tr) increased with the progress of breeding, whereas, intercellular CO2 concentration (Ci) decreased. Pn, Gs, Ci, Tr increased initially and then decreased, and they reached the peak at flowering stage. At late growth stage, Pn decrease of Ohio current cultivars were less than that of Liaoning current cultivars. Gs of Liaoning cultivars was higher than that of Ohio at seedling stage. Ci concentration from Liaoning was significant higher than those from Ohio at flowering stage and later seed filling stage. Tr of Liaoning current cultivars was higher than that of Ohio cultivars for the whole growth stages. SPAD had highly significant positive correlation with soybean yield at seedling, flowering stages and medium stage of grain filling, while Tr had significant negative correlation with seed yield. In summary, photosynthetic characteristics of cultivars had been improved together with soybean grain yield improvement.
In order to explore the effect of low light level on growth, photosynthesis and grain yield of soybean, effects of normal light (100%) and low light (20% of normal light) on changes of morphological characteristics, photosynthetic parameter and leaf structure and grain yield were investigated with 3 soybean cultivars as materials. The plant height of soybean increased by 0.98, 2.27, 1.39 times under low light conditions compared to those of normal light. The tallest plant was 69.83cm, which appeared in Wudou. But stem diameter, aboveground and underground biomass, and root shoot ratio of soybean decreased significantly under low light. Whereas, leaf thickness, palisade tissue thickness and spongy tissue thickness were decreased and cells were loosely packed. The difference of epidermal thickness was not significant in both treatments. Hypodermis thickness, palisade tissue thickness, spongy tissue thickness and leaf thickness were significantly different. The ratio of palisade tissue thickness and spongy tissue thickness of Nandou 12 were increased under low light level. In addition, contents of chlorophyll a and total chlorophyll in Nandou 12 and Yongshengheidou were increased under low light. Opposite results were found in Wudou. Leaf net photosynthetic rate and yield per plant of all cultivars in low light were decreased compared to those of normal light. Grain yield declined by 17%, 63% and 76%. Yield per plant of 3 soybean cultivars showed in trends of Nandou 12> Wudou> Yongshengheidou. However, yield per plant of Nandou 12 was less than those of Wudou and Yongshengheidou under normal light. Therefore, the response of soybean to low light was a complex issue. Choosing appropriate shade-resistant varieties was important for higher yield.
To evaluate heat tolerance and screen identification indexes of different genotypes soybean, 155 soybean cultivars (lines) from China and other countries were used and treated in intelligence greenhouse for 12 days (40±2℃, 9:00-16:00/d) at flowering and seed filling stages respectively. Natural temperature outside greenhouse was used as control. 13 traits were investigated at mature stage，including 100-seeds weight (X1), seed weight per plant (X2) and pod weight per plant (X3)，pods per plant (X4), seeds per plant (X5), seeds per pod (X6), shoot dry weight per plant (X7), stem length (X8), stem diameter (X9), main stem node number (X10), internode length (X11), protein content (X12), fat content (X13). The heat tolerance coefficients of all traits were used to comprehensively evaluate the heat-tolerance and select indexes of heat-tolerance for identification by principal component, membership function method, hierarchical cluster analysis and stepwise regression analysis. The results showed that 13 indexes were transformed into 6 comprehensive indexes through principal component analysis. The comprehensive heat-tolerance values (D) of flowering and seed filling stages were obtained by the membership function method and further used for cluster analysis respectively. The 155 soybean cultivars (lines) were classified into 6 types at both treatment stages, which were strong heat-tolerance type, heat-tolerance type, medium heat-tolerance type, medium sensitive type, sensitive type and strong sensitive type. The comprehensive heat-tolerance values (D) of both treatment stages were significantly correlated (r=0.262**) and had a certain consistency. Considering the identification results of both treatment stages, this study selected 4 heat-tolerance cultivars (lines) and 63 heat-sensitive cultivars (lines). Meanwhile, stepwise regression analysis showed that 100-seeds weight, pod weight per plant, seeds per pod, stem diameter, main stem node number, internode length and protein content could be used as identification indexes of heat tolerance at flowering stage. Seed weight per plant, pod weight per plant, pods per plant, seeds per pod, shoot dry weight per plant, stem length, and internode length could be used as identification indexes of heat tolerance at seed filling stage.
To better understand the effects of nutritional deficiencies on rapeseed roots, experiments were designed according to rapeseed (Brassica napus L.) nutrient requirement at seedling stage. Different nutrient deficiencies in hydroponics were applied for 28d cultivation using cultivar Zhongshuang 11 (ZS11) as material, the Changes (including phenotype, biomass, root-shoot ratio, chlorophyll (a, b), carotenoid content and root morphological traits) respond to N, P, K, Ca, Mg, B, Fe, Cu, Zn deficiencies were systematically investigated. Results showed that rapeseed seedlings exhibited various typical symptoms under nutrient deficiencies. Seedlings growth was significantly affected by macro-nutrients (N, P and K) deficiencies. Iron deficiency dramatically inhibited chlorophyll (a, b) biosynthesis in young leaves. Zinc deficiency facilitated accumulation of chlorophyll a and carotenoid in young leaves. Boron deficiency had the most influence on anthocyanin content of old leaves. Root biomass, root-shoot ratio and root growth of rapeseed seedlings were also affected by nutrient deficiencies. Root biomasses were significantly decreased by different nutrient deficiencies except Fe and Zn deficiencies. Root-shoot ratio was significantly increased by deficiencies of N, P, Ca, Fe, Cu and Zn. Primary root length was significantly increased by deficiencies of N, P, Mg, Cu and Zn. Lateral root length increased under N and P deficiencies. While both primary and lateral root growth were significantly limited by K, Ca and B deficiencies.
To find out the most effective application time of bolting fertilizer on rapeseed, ridge transplanted (on October 25th, 2013) cultivar Ningza 1818 (Brassica napus L.) was investigated. In base fertilizer, 375kg/hm2 compound fertilizer (with N-P-K, 16%-16%-16%), 187.5kg/hm2 urea and 15kg/hm2 boron fertilizer were used. In bolting fertilizer, 225kg/hm2 compound fertilizer and 150kg/hm2 urea were used. 3 application dates for bolting fertilizer application were chosen, which were the time when the plant stem heights were 10cm (CK), 30 cm and 50 cm. Internode length, canopy structure and yield of the transplanted rapeseed were investigated after the bolting fertilizer application. Result showed that earlier bolting fertilizer led to longer main stem, taller plant, and shorter rachis length. The later bolting fertilizer application led to lower main stem pod starting point, thicker canopy, and higher productivity of canopy structure. Among the 3 treatments, the yield of the latest treatment was the highest, with more pods and greater 1 000-seed weight. It could be concluded that when the bolting fertilizer was applied at the period of 50cm stem height of Ningza 1818, the rapeseed produced higher yield resulted from better population structure. The higher yield exceeded 4 000kg/hm2.
Some plant rhizosphere bacteria can secrete indoleacetic acid (IAA) to promote the plant growth and increase crop yield. This research aimed to screen IAA-producing strains from rhizosphere of peanut in sandy soil, and to analyze their promoting effect. 5 IAA-producing strains were isolated from rhizosphere of a healthy peanut plant. Among them, strain HS10 had the highest IAA-production ability and was identified as Bacillus tequilensis by 16S rRNA gene sequencing combined with its physiological and biochemical evaluation. HS10 produced maximum IAA at 24h of incubation with optimum conditions as 30℃, pH8, fluid volume 25 mL/250 mL, fructose and potassium nitrate as carbon source and nitrogen source respectively. Pot experiment demonstrated that HS10 significantly promoted plant growth and root system of peanut compared to the control.
To better understand the relationship between bird damage and glucosinolates content of rapeseed, 43 bred lines from the National Regional Trail of Rapeseed (2013) were investigated, and 8 injured lines at bud stage were analyzed on their glucosinolates. Results showed that 13 rapeseed lines had more than 23μmol/g glucosinolates (in rapeseed cake), and they had no bird damage. Others with lower glucosinolates than 23μmol/g had bird damage in different degrees. Their damage index ranged from 14.3% to 50.0%. Among them, 8 injured lines had damage index of 25.0% to 77.22%. The damage was more serious on lines with less seed glucosinolates. T test result showed that 6 aliphatic glucosinolates profiles had significant difference between injured and healthy lines. Aromatic and indolyl glucosinolates profiles had no difference between these two types of lines. Results also showed that the aliphatic profiles had negative correlation with the index of bird damage, indicating that aliphatic profiles were the main contributing factors.
Virulence of sunflower broomrape is different due to different physiological races. In order to clarify the physiological race composition of sunflower broomrape in China, international differential hosts of sunflower broomrape were used. They included AD-66, KruglikA-41, B-RO-02A, Record, LC-1002B, LC-1003B, L-1390 and LG-SS88. Detected broomrape were collected from 13 different areas from 4 provinces: Xinjiang, Inner Mongolia, Jilin and Hebei. Results showed that the samples were classified into 4 types: A, D, E and F. Among them, race D and E existed in wider area, and mainly distributed in Jilin and Inner Mongolia. The higher virulent race F was found in Siziwangqi of Inner Mongolia, and the lower virulent race A was found in Zhangjiakou in Hebei Province.
China is the largest consumer and producer of peanuts. But aflatoxin is the primary risk affecting peanut consumption safety and limiting the peanut export trade of China. Early warning technique of peanut aflatoxin contamination will change the aflatoxin removal after harvesting into early warning and prevention prior to harvesting. It was an efficient way in peanut aflatoxin control. The technique could reduce detoxification cost as well as significantly reduce secondary pollution of chemical and biological detoxification. This paper reviewed peanut early warning techniques including pre-harvest warning, post-harvest warning and whole course warning in order to provide better understanding in effective control of aflatoxin contamination.
Flaxseed, a potential source of α-linolenic acid, lignans, polyphenols, phytosterols and tocopherols, has broad application in food and healthcare industries. However, the contents and compositions of these bioactive components were susceptibly affected by planting area, variety, processing tissue and techniques, leading to decreased value-added utilization of flaxseed, flaxseed oil and defatted flour. This paper systematically reviewed the quality characteristics of flaxseed for value-promoted techniques. The techniques include extraction and purification of specific bioactive components, optimization of processing technology, development of high-value products and improvement of variety breeding.
Lipid transfer protein (LTP) play an important role in plant defense. In this study, BnLTP1 gene was cloned from Brassica napus L. It harbored 93bp, encoding 31-amino acids with molecular weight of 3.4 kDa. The gene was synthesized artificially by overlap polymerase chain reaction (PCR) and cloned into the prokaryotic expression vector ET30a/His-EDDIE-GFP. Its peptide BnLTP1 was expressed in Escherichia coli BL21. Antimicrobial activity demonstrated that BnLTP1 exhibited strong antimicrobial activity against Gram-positive bacteria, Gram-negative bacteria and yeast. BnLTP1 also had strong antifungal activity against several plant pathogenic fungi, including Sclerotinia sclerotiorum, Magnaporthe oryzae and Botrytis cinerea.
