Challenges and suggestions of Chinese rapeseed industry
Rapeseed industry is a central link in edible oil production, and plays a key role in edible oil safety. In order to resolve current problems of Chinese rapeseed industry, suggestions were put forward by combing present situation, prediction and practicable strategies of rapeseed industry. Challenges in Chinese rapeseed industry were analyzed, which included competition from international company; separation between breeding, popularization, and market demand; backward breeding model and R&D (research and development) in enterprise; lack of effective market regulation. Suggestions were made to improve rapeseed industry. First, comprehensive and rational modern rapeseed industry scientifc development view should be applied in regional distribution of rapeseed production. Second, rapeseed breeding of China should coordinated and a platform should be formed for breeding innovation. Third, rapeseed multifunctional development and utilization need to be improved to meet the new consumption demand. At last, market supervision must be strengthened to ensure the sustainability and healthy development of seed industry. This paper provided theoretical references for rapeseed breeding and production applications, and established a solid foundation for rapeseed production and popularization in China.
Mating behavior and sex pheromone release rhythm of Holotrichia parallela (Coleoptera: Melolonthidae)
Mating behavior and sex pheromone release rhythm of Holotrichia parallela was studied in this research. The maximum mating times were 3 for female and 4 for male. Average mating times were 1.06 for female and 0.91 for male. L-isoleucine methyl ester (LIME), a major component of pheromone, increased gradually from 14:00 and peaked at 19:00, then dropped sharply at 20:00 and remained low at 24:00. (R)-(-)-linalool (referred to as linalool below) maintained similar levels throughout the study period. Calling and mating activity significantly decreased LIME titer, but not linalool. Analyses of 11 samples collected during calling days (20 d-70 d) revealed that LIME production was affected by female age. LIME titers increased from 20 d to 45 d, and decreased from 45 d to 70 d. While linalool titers remained at similar levels at all sampling dates. The highest ratio between LIME and linalool was 12 and the lowest was 4. Field tests confirmed that the most attractive ratios of LIME: linalool in early season (June 1 to 20) and late season (August 1 to 20) were 6:1, while in the most serious injury stage (June 20 to August 1) was 12:1. This is the first report about circadian rhythmicity of sex pheromone in Holotrichia parallela, which provides a basis for controlling it in field.
Breeding and cultivation technology of high protein soybean variety ‘Qindou 2014’
Soybean variety ‘Qindou 2014’ with high protein content (47.79%) was bred through hybridization and pod mixed individual selection method. ‘96E218’ and ‘Pudou 10’ were used as female and male parent respectively. The near-infrared analytical method was used in low generation selection. ‘Qindou 2014’ also performed consistent high yield (3,739.8 kg/ha averagely), strong resistance to mosaic virus disease, wide adaptation, and good ftness to mechanized harvesting. The regional examination test was carried out and it was approved by the cultivar registration committee of Shaanxi Province in 2017. Experiments of sowing date and density were conducted to explore the suitable cultivation technologies for high yield. Results indicated that ‘Qindou 2014’ could fully exert its yield potential as sown at the density of 290,000 plants/hafrom May 25 to June 15. This study provides high quality soybean germplasm of future soybean industry.
Isolation and characterization of melanin derived from rapeseed meal
Melanin involves in various biological functions, widely used in cosmetic, pharmacology medicine and other felds. However, melanin application is limited due to low productivity and high cost. In this work, melanin extraction method from rapeseed meal (RSM) was explored. Effects of hydrochloric acid (HCl) concentration, ethanol concentration, extraction temperature and time, and solid-liquid ratio were evaluated systematically. According to results of single factor experiment and Box-Behnken experiment, the optimum extraction conditions of melanin from RSM were as follows: HCl concentration, 0.5 mol/L; ethanol concentration, 70%; extraction temperature, 40oC; extraction time, 1 h; solid liquid ratio, 1/4 g/mL. Under these conditions, extraction yields of crude melanin(CM) and purifed melanin (PM) were 9.00% and 1.44%, respectively. Compared with synthetic melanin (SM) from Sigma, the relative purities of CM and PM were 7.82% and 29.57%, respectively. Moreover, feedstuff value of RSM residue was also improved after melanin isolation by signifcantly reducing glucosinolate content.
RNA-seq analysis for soybean cyst nematode resistance of Glycine soja (wild soybean)
To explore genetic resource of wild soybean (Glycine soia. L), RNA-seq was used to investigate cyst nematode resistance of G. soja. Root transcriptome expressions were profled at 9, 15 and 20 d post inoculation (DPI) in resistant and susceptible G. soja to SCN (soybean cyst nematode). A total of 1,594 differentially expressed genes (DEGs) were identifed in roots infected by SCN compared with non-infected roots. In the resistant accession, 619, 65, and 8 DEGs were detected at 9, 15, and 20 DPI, respectively, while 327, 460 and 115 DEGs were detected at the same sampling point of susceptible accessions. DEGs were enriched in peroxidase gene sets which were involved in response to oxidative stress and oxidation reduction. Two gene families, ZIM transcription factor and WRKY transcription factor were enriched. WRKY transcription factor was only enriched in resistant accession. Moreover, gene expressions of 9 DEGs were validated by qRT-PCR. XLOC_023202, an unknown protein was up regulated more than 5 fold at 9 and 15 DPI in the resistant accession. These results provided an atlas of gene expressions of G. soja in response to SCN infection, and identifed candidate DEGs for future research.
An improved high-oleic line created by chemical mutagen of ‘Huayu 40’
By using chemical mutagenesis, ‘Huayu 40’, a normal-oleic (NO) large-seed high yielding peanut cultivar with wide adaptability was transformed into mutants with desirable high-oleic (HO) quality traits, comparable productivity and adaptability. Of the 3 chemical treatments, viz. 5 mM ethyl methane sulfonate (EMS), 25 mM EMS and 15 mM sodium azide (NaN3), only NaN3 produced HO M2 mutant plants. High oleate phenotype was initially identifed by near infrared spectroscopy (NIRS) screening, and was further confrmed by gas spectrometry (GC) analysis. Sequence analysis showed that HO plant had a 448G>A mutation in FAD2A and a 441_442insA mutation in FAD2B, respectively. Although the direct use of high yielding and stress resistant cultivars/lines to induce quality mutations might be a judicious choice to accelerate breeding, our results showed that chemical mutagenesis could quickly create HO peanut materials and expand the genetic bases of HO peanuts.
Preparation and characterization of nanocellulose from rapeseed hull
Rapeseed hull, a by product in rapeseed processing, deserves deep research for extensive application to promote its limited value at present. The aim of this study was to explore utilization of rapeseed hull as a source of raw material for nanocellulose. On the basis of pretreatment with sodium hydroxide solution and peroxide solution, nanocellulose from rapeseed hull (NRH) was prepared by sulfuric acid hydrolysis. Samples of different pretreatment stages were characterized using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, infrared spectrum and thermo-gravimetric analysis. Results showed that sodium hydroxide solution and peroxide solution pretreatment could signifcantly increase cellulose content of the material (p < 0.05). NRH prepared by sulfuric acid hydrolysis was of short rod structure, 50-250 nm in length with diameter of 5-25 nm. It had a typical type of celluloseⅠcrystal with 64.4% crystallinity. Initial thermal decomposition temperature of NRH was the lowest among all samples. NRH was expected to be applied in biodegradable composites. Therefore, this work will provide reference for further utilization of rapeseed hull as a low-cost source of nanocellulose.