There are large areas ofBrasscia napus, Fagopyrum esculentum and F. tataricumcultivation in northwest China and north China, their seeds left in soil after harvesting emerge in the next year and turn into weeds of serious damage to linseed, and this has become a major problem in linseed production. Field efficacy trial was conducted in linseed field to evaluate control effects of four kinds of herbicides on B. napus, F. esculentum and F. tataricum. The results showed that 40% MCPA-sodium and bromoxynil octanoate EC, 25% bromoxynil octanoate EC and 80% bromoxynil SP were high-effective herbicides to control B. napus. In linseed field, the plant and fresh weight control effects were 100% after 45 days treatment at the dosages of 600, 450 and 480 g/hm², the yield growth rate of linseed was 83.24%, 87.79% and 88.13%, respectively, the three kinds of herbicides were safe to linseed at the recommended dosages, their suitable dosages in large-scale demonstration and popularization were 600, 450 and 480 g/hm². 40% MCPA-sodium and bromoxynil octanoate EC, 25% bromoxynil octanoate EC, 80% bromoxynil SP and 24% picloram AS were high-effective herbicides to control F. esculentum in linseed field, the plant control effects were between 90.32% to 98.07% and the fresh weight control effects were between 97.30% to 99.27% after 45 days treatment at the dosages of 660, 450. 540 and 180 g/hm², the yield growth rates of linseed were from 87.31% to 92.80%, the four kinds of herbicides were safe to linseed at the recommended dosages, their suitable dosages in large-scale demonstration and popularization were 660, 450, 540 and 180 g/hm², 24% picloram AS need to use protective cover nozzle for directional spray. 24% picloram AS was a high-effective herbicide to control F. tataricum in linseed field, the plant and fresh weight control effects were 91.42% and 98.71% after 45 days treatment at the dosage of 216 g/hm², the yield growth rate of linseed was 94.24%, the herbicide was safe to linseed at the condition of directional spray using protective cover nozzle, its suitable dosage in large-scale demonstration and popularization was 216 g/hm².

The paper aims to investigate the colonization of GFP-labelled Bacillus amyloliquefaciens Bam22 in Brassica napus and lay a solid foundation for the application of this biocontrol agent. In this study, plasmid pGFP4412 containing green fluorescent protein gene was introduced into Bam22 cells by natural transformation method to construct GFP fluorescent labelled strain. The growth curve and inhibition activity to pathogenic microorganism of wild type strain Bam22 and Bam22-GFP were compared. The number of colonized strains in different tissue parts of B. napus was observed, and the colonization rule and ability were analyzed. The results showed that the labelled strain Bam22-GFP emitted strong green fluorescence under the excitation light wavelength of 488 nm, and the GFP fluorescent protein labelling and its gene expression did not affect the growth curve and inhibition activity to pathogenic microorganism of Bam22. The labelled strain could colonize in the B. napus plant through the root irrigation, and was transmitted from the root to the stem and leaf of B. napus. The colonization rules of Bam22-GFP in the root, stem and leaf all showed a trend of first increase and then decrease. On the 45 ^th day after inoculation, the labelled strains could still be detected in the roots, stems and leaves of B. napus. The results show that Bam22 could colonize and transfer in B. napus by root irrigation and display good colonization ability, and it has a good application prospect in agricultural production.

Aiming at the low quality of rape straw laying, which could result in the uncontrollable afterripening and great lost of pick- up value, the 4SY- 2.2 rape windrower was designed to achieve dividing, cutting, conveying and laying operation. The authors analyzed the movement process of rape straw on and out of the cutting platform, and then determined the essential condition for smooth convey and cast of rape straw. The analysis of the movement curve of the dropping rape straw showed that the rape laying angel was related with its own biologic characteristics, windrower structural parameters and motion parameters. Field experiments showed that the laying of rape was orderly after windrower operation, the average value of laying angel was 48.4°, the average layer height was 511.6 mm and the width was 797.8 mm, the average height of the cutting stubble was 365.5 mm. It indicated that the laying quality could reach the requirement of after-ripening and pick-up operation.

In order to evaluate the suitability of climate condition in rape’s growth period, and provide the scientific guidance for the government strategy and farmers’ field management and agricultural production, by using the meteorological data from rape planting area in Anhui Province, and on the basis of physiological characteristics of rape and the research results of predecessors, the suitability models in different regions about climate were constructed, and the suitability models had been verified. According to the relationship between climate suitability and bumper or poor harvest index of rape, climatic suitability indicators on different time scales were set up. The results indicated that the climatic suitability model could dynamically reflect the suitable level of meteorological condition on rape growth/yield. Climatic suitability indicators had high evaluation accuracy, and they could satisfy the needs of operational services.

The paper aims to analyze the main factors affecting the yield of Brassica napus with different maturity stages under climatic conditions in Chengdu, and provide a theoretical basis for resistance breeding of B. napus. Correlation analysis, path analysis and principal component analysis were used to analyze the relationship between the agronomic traits, the stem breaking resistance, the incidence of Sclerotinia sclerotiorum and the yield of B. napus. The yield of early-maturing rape varieties was significantly and positively correlated with the number of effective siliquae per plant, the number of seeds per siliquae, and the breaking resistance of the middle and upper part of the stem. The yield of mid-maturing rape varieties was significantly and positively correlated with the plant height, the first branch height, the number of effective siliquae per plant, the breaking resistance of the lower part of the stem, and the breaking resistance of the lower and middle part of the stem. The greatest direct path coefficient of yield was the number of effective siliquae per plant in both early-maturing rape varieties and mid-maturing rape varieties. The greatest indirect comprehensive effect on yield were the number of seeds per siliquae in early-maturing rape varieties and the breaking resistance of the lower part of the stem in mid-maturing rape varieties, respectively. The principal component analysis showed that the 15 agronomic traits were divided into four major categories in early-maturing rape varieties and three major categories in mid-maturing rape varieties. For early-maturing rape varieties, they were lodging resistance traits, plant type traits, yield components traits and disease resistance traits. For mid-maturing rape varieties, they were yield components traits, plant type traits and lodging resistance traits. Under the natural climatic conditions of Sichuan Province, in the breeding of early-maturing and mid-maturing rape varieties, the selection of plant type, lodging resistance traits and disease resistance should be strengthened while ensuring the yield components traits.

The lateral bud, flower bud receptacle, hypocotyl and cotyledon derived from sterile seedlings of elite Brassica napus restorer line 627R, 621R and 616R were used as explants for tissue culture. The research explored the effects of different seedling ages, pre- culture time, different hormone ratios of pre- culture medium, callus differentiation medium, shoot induced medium and shoot growth medium on shoot regeneration and plant growth vigor. The high frequency of shoot regeneration resulted from hypocotyl and cotyledon derived from 6 days growth seedlings cultured in the following procedure, after 3 days in pre-culture medium (MS+ 2.0 mg/L 2,4-D+ 1.0 mg/L 6-BA+ 30 g/L sucrose+ 8 g/L agar, pH 5.85, the explants were transferred to callus differentiation medium, MS+ 3 mg/L 6-BA+ 1.0 mg/L NAA+ 5 mg/L AgNO3+ 30 g/L sucrose+ 8 g/L agar, pH 5.85, or MS+ 3 mg/L 6-BA+ 1.0 mg/L IAA+ 5 mg/L AgNO3+ 30 g/L sucrose+ 8 g/L agar, pH 5.85. The high frequency of shoot regeneration derived from lateral and buds in the flower bud development could be cultured 30 days in callus or shoot regeneration medium(MS+ 10 mg/L 6-BA+ 1 mg/L NAA+ 30 g/L sucrose+ 8 g/L agar，pH 5.85). All the plants from explants culture had abundant fine roots such as increased root hair number and length, and excellent seedling vigor after transferring to medium with 15 mg/L CCC (MS+ 15 mg/L CCC+ 15-20 g/L sucrose+ 8 g/L agar，pH 5.85) for 30 days. The tissue culture system established for different explants of Brassica napus restorer line will accelerate the reproduction and evaluation of rapeseed varieties.

In order to study the influence of different Zinc (Zn) levels on physiological characteristics, Zn accumulation in grains of rape, the plant growth, physiological characteristics, concentration and accumulation of Zn in grain for five varieties (LPJCZ, ENW, SYKC, NTHYC and H33) were compared at Zn (0, 1.0, 5.0, 10.0 and 20.0 mg/kg) treatments in pot experiments. The dry weights of roots, leaf, straw, grain and plant, physiological characteristics, concentration and accumulation of Zn significantly differed among different varieties and Zn levels. The activities of net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), and dry weights of plant, straw, leaf and grain increased at Zn≤5.0 mg/kg. Zinc concentration of roots, straw and leaf for five varieties, and grain Zn concentration for LPJCZ and SYKC increased by increasing of Zn, but grain Zn accumulation for five varieties, and grain Zn concentration for ENW, NTHYC and H33 increased at Zn≤5.0 mg/kg, then decreased at Zn>5.0 mg/kg. The high concentration and accumulation of Zn in grain were observed in ENW by 172.34 mg/kg (2.932 mg/pot) and 164.10 mg/kg (2.575 mg/pot) at 5.0 and 10.0 mg/kg Zn treatments.

Rapeseed is the most important oil crop, and stable increase of rapeseed yield is significant for edible oil security. In the past 30 years, China’ s rapeseed breeding has achieved significant progress in quality improvement while the rapeseed yield is in a wandering status. The high photosynthetic efficiency breeding of Brassica napus could increase yield by changing the space of leaves, branches and pods, increase the net photosynthetic rate and decrease respiration consumption. This paper reviewed research progress of high photosynthetic efficiency breeding of rapeseed (Brassica napus L.) by 4 morphological traits: leaf type, plant height, branching characteristics and pod type, and 5 physiological traits: dry matter, photosynthetic area, net photosynthetic rate, chlorophyll content and root. The study pointed out 5 problems in current rapeseed breeding: ①more studies on individual trait but less study on population traits; ②more studies on individual photosynthetic factor but less holistic study; ③more studies on static traits but less study on dynamic traits;④ physiological high photosynthetic efficiency breeding of Brassica napus was still in an exploring stage;⑤ less research on root. Finally, the author suggested that the research of rapeseed highly photosynthetic efficiency breeding in the future should inherit the achievements of available rapeseed breeding, and combining with high oil content breeding, mechanization, ecology breeding and heterosis.

Film mulching is an effective technology for yield increase of dry cultivation, which can significantly improve the ecological condition of soil moisture and temperature, and promote plant growth and development. In order to understand the effects of film mulching cultivation on the growth, yield and quality of spring rapeseed in Tibet, based on field cultivation with ‘Shanyou No.4’ as the material, the effects of film mulching cultivation on the growth period, dry matter accumulation, agronomic characters, yield and quality of spring rapeseed were analyzed. The results show that compared with open field cultivation, the film mulching cultivation could shorten the growth period by 5 days, increase the plant height, branching position, effective branch number, effective pod number per plant, seed number per pod, and decrease 1000-grain weight. The yield of film mulching cultivation was 2601.67 kg/hm², increased by 508.34 kg/hm² compared with that of open field cultivation, and the yield increase rate was 24.28%. The oil content was increased by 2.4%, while the content of erucic acid and glucosinolates did not change much. The study indicates that the film mulching cultivation can improve the yield and quality of spring rapeseed in Tibet, and can be used as an important cultivation measure in the production.

In order to provide technical support to light simplified production of rapeseed in delayed harvest rice fields of eastern Hubei Province, this study made a comparison on the yield and benefits of rapeseed under two aerial sowing modes based on the same crops for rotation condition. Field experiment of two years was conducted with winter rapeseed as material, and the data of yield and benefits of rapeseed under the two aerial sowing modes was obtained. Compared with rotary-tillage aerial sowing mode, the yield of rapeseed under no-tillage aerial sowing mode was increased by 561.5 kg/hm² on average, and the rate of yield increase was 25.7% on average in the two years. The main reason of yield increase was that the number of siliques per plant increased significantly, and the average increase was 28.6%. The production value of rapeseed under no-tillage aerial sowing mode was increased by 3023 yuan/hm², and the gross income was increased by 4523 yuan/hm² on average in the two years. The main reason was that the no-tillage aerial sowing mode reduced the investment on removing straw from the field, seed and pesticide, preparing soil by rotary tillage, and weeding and disease preventing. The total investment decreased by 1500 yuan/hm² on average in the two years. The no-tillage aerial sowing mode can not only reduce the investment, but also increase the yield and benefits of rapeseed. It has the advantages of cost saving and benefit increasing, and is suitable for popularizing and applying in delayed harvest rice fields in eastern Hubei Province.

The paper aims to select new forage rape varieties suitable for planting in northeast Sichuan. Six new double-low rape lines were used as experimental materials. The biological yield, botanical characteristics, nutritional components, dynamic changes of agronomic characters and nutritional quality during cutting were recorded, and their feeding value was evaluated. The results are as follows. (1) The lines regenerated during cutting at the early flowering stage, and they could be cut twice in the whole growing season, with a cutting interval of 35-37 days. The fresh grass yield was 43.24-50.89 and 13.94-20.03 t/hm² respectively for the two cutting, the annual fresh grass yield was 57.40-70.46 t/hm², and the annual hay yield was 6.11-7.28 t/hm². Among the rape lines, the fresh grass yield of ‘Zhongmianyou 783’ was the highest, which was 70.46 t/hm² and significantly higher (P<0.05) than that of other test lines. (2) Different rape lines showed significantly different agronomic characters at the first cutting. The plant height of ‘Nanyou 714’ was the highest, up to 162.11 cm; ‘Zhongmianyou 783’ had the largest number of leaves (19.11), and the stem leaf ratio of ‘Nanyou 658 ‘was the lowest, which was 0.91. (3) The crude protein content of ‘Nanyou 12’ was 15.64% at the first cutting, which was significantly higher (P<0.05) than that of other test lines, neutral detergent fiber of ‘Zhongmianyou 783’ was the lowest (25.65%), and acid detergent fiber of ‘13Za768’ was the lowest (20.80%). (4) With the advance of the growth period, the plant height of each line increased gradually, and the plant height did not change in the late pod setting stage. The number of leaves increased first and then decreased, and the number of leaves was the most at the initial flowering stage. The dry matter content and stem leaf ratio increased continuously with the advance of the growth period. (5) The crude protein content of each line decreased with the advance of the growth period, and was the highest at initial flowering stage, which was 12.87%-15.64%. The change trend of neutral detergent fiber and acid detergent fiber were the same, and most of them increased with the advance of the growth period. The content of crude ash decreased with the advance of the growth period. Most of the crude fat increased first and then decreased, and reached the highest at full flowering stage. The feeding value of the first cutting of each rape line was 231.20-262.47, and there was no significant difference (P<0.05) between ‘Zhongmianyou 783’ and ‘13Za768’, but the feeding value of the two lines was significantly higher than (P<0.05) that of other lines. ‘Zhongmianyou 783’ has the best comprehensive performance in the test site and can be popularized and utilized in similar ecological areas.

The goal of drought-resistant breeding of rapeseed (Brassica napus L.) is to cultivate water-saving and high-yield new varieties under drought conditions. In this research, drought-resistance identification of rapeseed was studied through morphological and growth indicators, physiological and biochemical indexes (including photosynthesis, osmotic adjustment, antioxidant enzyme activity, endogenous hormones, water use efficiency, etc.), yield and quality indexes, and comprehensive evaluation indexes, etc. It was found that water stress had an important influence on the morphology and growth of rapeseed at different stages. The existing problems in drought resistance identification of rapeseed were analyzed by retrospective study, while the relevant indexes and techniques were discussed to provide references for research and production of rapeseed drought resistance. It is concluded that the molecular mechanism of rapeseed drought resistance would bring drought resistance breeding to a new stage.

Based on the observation data of rape fixed-point experiment from 2011 to 2018, the effects of low temperature on rape podding rate and seed number per pod were analyzed in different flowering periods. Furthermore, the quantitative relationship between meteorological factors and seed loss rate was established. The results showed that: the effects of low temperature on seed setting were mainly moderate and severe before February 25, mainly mild in the middle and last ten days of March, and mainly mild and moderate from February 26 to March 10. The relationship between rape seed loss rate with the average daily minimum temperature and daily average rainfall during the flowering stage was not significant, but the relationship between seed loss rate with average temperature, average daily maximum temperature, average sunshine hours, and average daily relative humidity at flowering were significant. With the decrease of average flowering temperature, the average maximum temperature decreased and the relative humidity increased. When the relative humidity of air was 70% and the daily average temperature was ≤6.9℃, or the relative humidity of air was 80% and the daily average temperature was ≤8.0℃, rape would suffer from moderate damage. When the relative humidity of air in flowering time was 80% and the daily average temperature was ≤4.3℃, or the relative humidity of air was 85% and the daily average temperature was ≤4.8℃, the rape would suffer from severe damage. The cold accumulated temperature indexes of rape flowering and seed setting under different weather types were determined. When the cold accumulated temperature index of sunshine and low temperature weather was ≥16.5℃, or the index of cold accumulated temperature of no sunshine and low temperature rainy weather was ≥5.0℃, it was moderate damage. When the cold accumulated temperature index of sunshine and low temperature weather was ≥37.5℃, or the cold accumulated temperature index of no sunshine and low temperature rainy weather was ≥26.0℃, it was severe damage. The results could provide technical support for early warning evaluation and agrometeorological service of disaster reduction and prevention in rape production.

To study the relationship among agronomic traits of Brassica napus and improve the breeding efficiency of new varieties, the correlation analysis and principal component analysis of agronomic traits were carried out for 229 DH materials, those traits included plant height, height of branch, number of first effective branches, height of main inflorescence, number of main inflorescence pods, economic yield per plant and biological yield per plant. The results showed that: plant height, height of branch, height of main inflorescence, economic yield per plant and biological yield per plant were partial to male parent, but the number of first effective branches and the number of main inflorescence pods were partial to female parent. The correlation analysis indicated that plant height, height of branch, number of main inflorescence pods, economic yield per plant and biological yield per plant were significantly and positively correlated, and the number of first effective branches was negatively correlated with plant height and branch height. Through the principal component analysis, the rapeseed quality traits could be integrated into plant height, number of first effective branches, and number of main inflorescence pods and branch height, with the total cumulative contribution rate of 90.0%, which basically covered the full information of the agronomic traits of Brassica napus.

To explore the role and economic value of honeybee pollination in oilseed rape production, the annual value of the rape production attributable to honeybee pollination and the pollination requirements of bee colonies were evaluated based on honeybee pollination dependency model. The results indicated that the total value of honeybee pollination service to oilseed rape production in China in 2018 was 10.419 billion Yuan, accounting for 15.75% of the annual domestic oilseed rape production value (almost 66.141 billion Yuan). In Sichuan, Hubei and Hunan, the value of honeybee pollination service to rape production was all over 1 billion Yuan. It is estimated that over 16.3765 million bee colonies are needed each year to pollinate oilseed rape in China, more than the present 9.0884 million bee colonies. Hunan and Sichuan have the largest demand for honeybee pollination in rape production, accounting for more than 1/3 of the total domestic bee colonies. Therefore, bee pollination is an important input in rape production, the public awareness of the economic value of bee pollination should be gradually raised, and bee pollination technology in rape production should be vigorously promoted.

To breed rapeseed varieties with early maturity and yield stability for the mountain area in Yunnan Province, and to promote the sustainable development of agricultural production, the domestic excellent varieties were introduced and crossed with the local elite varieties with good quality, high yielding and high level resistance. Two new rapeseed varieties of‘Yuhongyou 3’and‘Yuhongyou 4’with early maturity, high oil content and yield stability were developed and released at provincial level in Yunnan using multiple generation selection and quality analysis. In this study, the breeding process of the new rapeseed varieties of ‘Yuhongyou 3’and‘Yuhongyou 4’was elaborated. Furthermore, the suitable cultivation techniques of these two varieties were provided. The breeding process and cultivation techniques are important for the rapeseed breeding in Yunnan, and the application of these two new rapeseed varieties plays a significant role in promoting the development of rapeseed industry in Yunnan Province.

By the means of extensive collection of various information, this paper reviewed the status quo of the development of oilseed rape industry in Chongqing, summarized the constraints in terms of low planting benefits, weak industrialized management, and lagging brand building. Moreover, it analyzed favorable conditions and policies of planting foundation, comparative advantages, and planting space and opportunities for industrial pattern and planting structure. Therefore, we put forward suggestions including establishing high-quality oilseed rape industrial production bases, advancing farming system reform, improving the production mechanization rate, and accelerating the integration of agriculture and tourism development, aiming to provide intellectual support for the sustainable and healthy development of Chongqing’s oilseed rape industry.

To explore the adaptability and wind erosion resistance of different varieties of winter rapeseed in semi-arid agricultural areas of central Gansu, six winter rapeseed varieties (winter Brassica rapa ‘HN12PZ16-2’,‘HN12PZ16-65’ and ‘Pingshi 8’, winter Brassica napus ‘QL-GAU-201’, ‘QL-GAU-196’ and ‘Low(1)-19’) were selected as the research objects, and their overwintering rate, wind erosion resistance, yield and oil content were analyzed in detail. The results showed that, the root-shoot ratio of winter Brassica rapa was significantly higher than that of winter Brassica napus before winter, and the overwintering survival rate was also significantly higher than that of winter Brassica napus. The overwintering rate of ‘HN12PZ16-65’ was the highest, reaching 88.33%. The yield and oil content of winter Brassica rapa were significantly higher than those of winter Brassica napus due to high plant height and 1000-grain weight, and the yield (2937.00 kg/hm²) and oil content (43.67%) of ‘HN12PZ16-65’ were the highest. The dry matter accumulation of winter rapeseed was high before winter, which increased the starting wind speed of farmland and significantly reduced the wind erosion of farmland. The wind erosion of farmland soil of the six winter rapeseed varieties decreased by 88.77%-92.79% compared with that of the open field. Therefore, ‘HN12PZ16-65’ has strong drought resistance, high overwintering rate, high yield and oil content, good adaptability and good wind erosion resistance in central Gansu, which is suitable for wind erosion wintering cultivation in semi-arid agricultural areas.

The aims are to determine the effect of Coniothyrium minitans on soil microbial community structure, and to provide a theoretical basis for the application of this biocontrol fungus in production. The occurrence of Sclerotinia stem rot was investigated by spraying C. minitans as treatment group (CM) and spraying clean water as control group (CK), and the changes of soil microbial community were analyzed by high-throughput sequencing technology. The results showed that the incidence rate and disease index of Sclerotinia stem rot in control group were up to 74.64% and 46.13, respectively. While, the incidence rate and disease index were reduced to 23.33% and 9.37, respectively, in treatment group, and the control effect was 79.70%. In addition, the soil microbial community structure was changed and the abundance and diversity of soil fungi were significantly increased after spraying C. minitans. At the phylum level, the relative abundance of Proteobacteria, Gemmatimonadetes, Ascomycota, Mortierellomycota and Basidiomycota were increased, but the relative abundance of Actinobacteria was decreased after spraying with C. minitans. At the genus level, the abundance of Sphingomonas, Lysobacter, Dokdonella, Trichocladium, Fusarium, Aspergillus and Plectosphaerella were increased, while, the relative abundance of unidentified_Chitinophagaceae, Stenotrophomonas, Geobacter, Thielavia and Cutaneotrichosporon were decreased after spraying with C. minitans. The application of C. minitans could effectively control Sclerotinia stem rot, increase the abundance and diversity of soil fungi, and improve soil microbial community structure. The results of this study can provide a basis for the large-scale promotion of C. minitans in the field.

To select safe, high efficient and low cost herbicide for rapeseed in sprouting stage, the control effect of different herbicides and their application amount on weed in rapeseed field were studied. The results showed that all the applied herbicides were safe to rapeseed plants in this experiment, and the control efficiency was above 94% to gramineous weeds and broadleaf weeds in the field, the income increase was above 4340 yuan/hm2. Among all the herbicides application, soil surface spraying after planting with 50% different pine·acetochlor 1200 mL/hm2 mixed with water 1125 kg/hm2 had the best weeding and yield-increasing effect.

The aims are to alleviate the negative effects of rice-residue returning to field on direct-seeding rapeseed, and achieve the full and strong seedling. ‘Fengyou 737’ was used as material, and the effects of different seed soaking reagents on the germination and seedling of direct-seeding rapeseed were studied under rice-residue returning to field. Results showed that under rice-residue returning to field, treated with C₁ (40 mg/L gibberellin + 200 mg/L ammonium molybdate + 2000 mg/L potassium dihydrogen phosphate + 400 mg/L boric acid) and C₂ (100 μmol/L melatonin + 200 mg/L ammonium molybdate + 2000 mg/L potassium dihydrogen phosphate + 400 mg/L boric acid), the number of seedlings per square were increased by 23.28% and 3.97% compared with that of CK. The root length and hypocotyl length of seedlings treated with C₁ reagent were increased. The toot length was increased and the hypocotyl length was decreased compared with those of CK in the C₂ reagent treatment. The dry matter accumulation of seedlings treated with C₁ and C₂ reagents were all increased compared with that of CK. We also found that C₁ and C₂ reagents relieved the harmful effect of rice-residue returning to field on the seedling of direct-seeding rapeseed. C₂ reagent treatment was better than C₁ reagent treatment by promoting the root development and strong seedling under rice-residue returning to field.

In order to explore the application effect of silicon, calcium, magnesium, phosphorus and potassium fertilizer on rape, a field plot experiment was conducted during 2013-2014 in Anhui Province to investigate the effects of silicon, calcium, magnesium, phosphorus and potassium fertilizer on the rape yield, utilization of phosphorus and potassium and soil nutrient contents. The results showed that in comparison with farmer practice fertilizer (CF₁) and farmer practice fertilizer with phosphorus and potassium halving (CF₂), silicon, calcium, magnesium, phosphorus and potassium fertilizer could increase yield of rape. And the yield was 4.0%-20.8% and 10.2%-28.0% more than that of CF₁ and CF₂, respectively. Silicon, calcium, magnesium, phosphorus and potassium fertilizer could increase the number of seeds per pod. With the increasing of the application amount, contents and uptake amounts of phosphorus and potassium in grain increased, and the application of 1500 kg/hm² (T₁₀₀) was higher than farmer fertilizer practice. Silicon, calcium, magnesium, phosphorus and potassium fertilizer could increase soil available calcium, available magnesium and pH, but had no significant effects on soil organic matter and available nitrogen content. It suggested that the yield of rape, phosphorus and potassium absorption and soil nutrient contents could be significantly improved by the rational application of silicon, calcium, magnesium, phosphorus and potassium fertilizer, which was1500 kg/hm² (T₁₀₀).

Owing to thinner hull, less fiber, higher oil and protein content than its black-seeded counterpart with a dark, thicker, and more lignified seed coat, yellow seeded variety is an important goal for breeding of oilseed Brassica napus. In order to investigate genetic classification and diversity, we tested the allelisms among different yellow-seeded accessions and studied the genetic diversity through clustering. Results showed that according to the result of allelism test, by investigation of the segregation of seed coat colour in F1 and F2 of cross between different accessions, 11 yellow-seeded rapeseed accessions could be divided into five groups: group Ⅰ including‘Youyan10’ , CZV55, E718, and Arm, mostly followed a dominant inheritance model; group Ⅱ including Q33 and D615, in incomplete dominant inheritance; group Ⅲ including 2006C, X2006, and 740C; the rest two groups only including Polo and HY15, respectively. The last three groups were generally in recessive genetic model. However, the inheritance of yellow- seeded traits of‘Youyan10’and 2006C was various from dominant to recessive when they crossed with the different genotypes of brownseeded. Cluster based on SSR molecular polymorphism showed that 35 yellow- seeded rapeseed accessions could be classified into three main groups: B.napus, B.rapa, and B.juncea. The group B.napus could be further divided into eight subgroups, the representations of them were 2006C and 740C, Youyan system, Q33, Ramiro from French, GQ4 from Shaanxi, Arm and prof from Canada, and yellow Polo from Polish cultivar Polo. This generally agrees with the pedigrees, breeders and originations. The results could provide the theoretical basis for the heterosis utilization of yellow- seeded rapeseed.

As the most important oil crop in China, rapeseed plays an important role both in our daily life and industrial production. In this paper, the biochemical process of seed oil synthesis, three main ways and the progress of improving oil content by genetic engineering techniques in rapeseed were reviewed. The paper also introduced the latest research advances of genetic engineering techniques which used in improving the quality of rape fatty acids，such as oleic acid, erucic acid and lauric acid. In addition, the application tendency of genetic engineering techniques in rapeseed oil was discussed.

To explore the response mechanism of soil microecology to rice-rapeseed system annual tillage patterns, a rice-rapeseed rotation experiment was conducted on the long-term no-tillage direct seeding soil of Dongting Lake area of north Hunan. The differences of soil enzyme activity, microorganism quantity, diversity and microbial community function between the double no-tillage direct seeding (DNT) and double rotary-tillage transplantation (DT) were compared to illustrate the effects of different tillage patterns on soil microecology. The metagenomic sequencing showed that there were similar bacterial types under the two patterns, the bacterial diversity was higher under DNT, but the fungal diversity under DT was higher. Function analysis illustrated that the relative abundance of aerobic and facultative anaerobic prokaryotes was higher in DNT; the relative abundance of prokaryotes related to nitrogen metabolism was higher in DNT, while the relative abundance of prokaryotes related to carbon metabolism was higher in DT. The number of culturable bacteria, fungi, actinomycetes and nitrifying bacteria in DNT soil was significantly lower than that in DT, while the number of ammonifying bacteria was significantly increased. Enzyme activity analysis showed that urease activity of DNT was 58.12% higher than that of DT, while the activities of invertase, phosphatase and cellulase decreased by 28.57%, 11.00% and 57.73%, respectively. The results indicated that the DNT rice-rapeseed rotation system was beneficial to improve the bacteria diversity, and the relative abundance of aerobic and facultative anaerobic prokaryotes, and was conductive to the transformation and utilization of nitrogen in the soil. The study provides a basis for the selection of reasonable tillage patterns of rice-rapeseed system in Dongting Lake area.

Soil cadmium pollution is serious in southern China, and has a great deal of adverse effects on agriculture development and safety of agricultural products. Phytoremediation is a promising way to restore cadmium contaminated farmland, but suitable phytoremediation plants are insufficient. In this study, an economic crop of Brassica napus, which is widely planted in the middle and lower reaches the Yangtze River, is taken as raw material to study the effects of excessive cadmium content on Brassica napus growth and the quality of rapeseed oil. Four different cadmium concentrations of 0, 5, 15 and 25 mg/kg are adopted in pot cultivation. The results show that excessive cadmium content could have adverse effects on the growth of Brassica napus, but the cadmium content in rapeseed oil is far lower than that in the international standard, indicating that the rapeseed oil produced on cadmium pollution soil would not affect its consumption value. At the same time, Brassica napus used as remediation plant could increase the income of local farmers and the supply of vegetable oil in China, to alleviate the increasing shortage of edible oil supply. Therefore, Brassica napus is an ideal remediation plant for cadmium contaminated soil.

The paper aims to decipher the role of volatile odorants of flowers in attracting foraging of pollinators. Solid phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) were used to detect the components of volatile odorants in the whole flower, anther and nectar of pear and oilseed rape flowers, principal component analysis and correlation analysis of insects foraging were also conducted. 9 and 23 volatile odorants of pear and oilseed rape flowers were identified respectively, alkanes, accounting for 44.44%, was the main volatile odorant of pear flowers, odor contributions of pear flowers mainly were from dimethyl sulfide, tetradecycloheptachiloxane, phenylpropionitrile, benzaldehyde and other compounds studied by principal component analysis. Esters and alkanes accounted for 8.7% and 16.09% respectively, which were the main volatile odorants of oilseed rape flowers, odor contributions of oilseed rape flowers mainly were from compounds such as reverse 2-hexenal, isothiocyanate-2-phenyl ethyl ester, 4-isothiocyanate root-1-butene, dimethyl disulfide, dimethyl disulfide and other compounds studied by principal component analysis. Anthers had more volatile odorants than nectar. There were 4 orders, 10 families and 11 species of pollinators in the test site, and the number of pollinators between pear and oilseed rape also had a significant difference (P<0.05). However, there was no significant correlation between each component and the number of pollinators (P>0.05). Significant differences are identified between the constituents of volatile odorants of pear and rapeseed flowers, laying a foundation for further studies on the role of major contributors of odorants in attracting pollinators.

The paper aims to study correlation between of pod length and the yield components in hybrid Brassica napus, 649 combinations of Brassica napus were used for field experiment, laboratory test and correlation analysis. The results showed that: The average pod length of Hybrid Brassica napus was 6.4596 cm, the range was 4.7184-8.6463 cm, Pod length between 5~7cm material accounts for 96.76% of the proportion of the total, However, the material with average angular fruit length greater than or equal to 8cm is only 1.54% of the population, and the material less than 5cm is only 1.70% of the population, Instructions there are few short - Angle pod in the rape.Pod length and 1000-grain weight(r=0.3815), seeds pod(r=0.4324) and yield were very significant positive correlation (r=0.2347), with pods per plant(r=0.0076) and pod length has no significant positive correlation, at the same time in the breeding of longer pod materials that not only can improve the Angle of 1000-grain weigh , seeds pod and yield plant , and will not reduce the pods per plant. Therefore, increase of rape pod length, improve rape production.

To meet the needs of fresh-cut rape packaging, this paper adopted the combination of the packaging bags with the modified atmosphere (MA) windows of different permeability and different areas to conduct the tests, and through the analysis of the sensory quality and gas composition in the packaging bags of fresh-cut rape, developed the optimum modified atmosphere packaging (MAP) of fresh-cut rape. The results showed that the suitable MA window for fresh-cut rape was: the transmittance rates of O₂ and CO₂ were 4×10⁵ and 1.6×10⁶ cm³/(m²·d·atm), respectively; the area of rape needed was 2~6 cm²/kg. Comparing the permeability of modified atmosphere window and film, the permeability amount of O₂ and CO₂ in packaging bags suitable for fresh-cut rape should be 2.08×10³-2.99×10³ and 0.96×10⁴-1.32×10⁴cm³/(kg·d·atm) respectively, which could solve the problem of odor and maintain shelf quality for more than 5 days. When the appropriate gas concentration of fresh-cut rape was reached, O₂ was 6.50%-9.69% and CO₂ was 6.46%-7.10%. The MAP bag can not only improve the storage quality of fresh-cut rape and make fresh-cut rape in the appropriate gas state, but also solve the odor problem caused by anaerobic breathing, and retain the original smell of fresh-cut rape and prolong the shelf life.

The paper aims to study the correlation and regression relationship between the harvest index and plant traits. We determined harvest index, yield per plant, plant height, 1000-grain weight, seeds pod, the main inflorescence pod length, pods per plant, effective branch position, first branch number and the main inflorescence length of 649 new combinations of Brassica uapus . The harvest index of different new combinations varied significantly. The amplitude of variation was 0.1292-0.3358, and the average was 0.2247. The proportion of harvest index which was more than 0.30 only accounted for 0.31%. The harvest index showed highly significant correlation with yield per plant, grain number, number of silique per plant, first branch number, length of main inflorescence and plant height. The results of regression analysis showed that five traits including plant height, number of silique per plant, length of main inflorescence, 1000-grain weight and grain number had greater impact on the harvest index. Thus, we can improve grain number and 1000-grain weight of breeding materials by utilizing the correlation among the traits and selecting materials that have longer silique and main inflorescence. In addition, we can select materials which are relatively higher with longer main inflorescence and more branches to improve the number of silique per plant of the bred material, to breed a combination (or variety) with higher single plant yield eventually.

The whole-process mechanization is an inevitable trend in rape production, but the current level of mechanization in rape production in China is still low. This study analyzed the situation of the mechanized production of direct-seeding rape, and elaborated the high-yield and high-efficiency agronomic measures suitable for the whole-process mechanized production of direct-seeding rape in China from six aspects: variety selection, farmland preparation, sowing, fertilization, pest control and harvesting. In view of the problems in the promotion of direct-seeding rape, this study put forward corresponding improvement measures and possible research priorities in the future, in order to enhance the mechanized production level of direct-seeding rape, accelerate the integration of agricultural machinery and agronomic measures, and promote the high-quality development of the rape industry.

To explore the effects of tobacco-rape rotation and balanced fertilization on soil organic carbon (SOC) content, a two-factor split plot design, which included tobacco rotation with three rape varieties (‘Chongrongyou 1’, ‘Deyouzao 1’ and ‘GSX-1’) and balanced fertilization (nitrogen reduction and phosphorus increase), was adopted to analyze the content of soil total organic carbon (TOC) and dissolved organic carbon (DOC) in rape season and tobacco season. The results showed that from the initial stage of rape transplanting to harvest, the SOC content increased to varying degrees, ranging from 7.7% to 166.49%. The content of TOC and DOC of the rotation increased compared with those of the control, and the content of TOC and DOC of ‘Chongrongyou 1’during the harvest period (180 d) were the highest, which were 1.26 and 4.78 times that of the control, respectively. In the whole growth period of tobacco, except some individual treatments, the DOC content in soil showed a downward trend, while the TOC content increased. In addition, in terms of fertilization mode, nitrogen reduction treatment had the best effect. In the harvest period of tobacco, except ‘Deyouzao 1’, the TOC content of soil in nitrogen reduction treatments was the highest, which was 1.20, 1.44 and 1.02 times that of the control, respectively. In conclusion, the SOC content is relatively high under ‘Chongrongyou 1’ -tobacco rotation and nitrogen reduction, which is a good local planting system.

To investigate the synergistic effect of poly-γ-glutamic acid (γ-PGA) on different forms of nitrogen fertilizers (urea, ammonium chloride, sodium nitrate and combined application of organic and inorganic fertilizers), a pot experiment was conducted to study the effects of γ-PGA combined with different forms of nitrogen fertilizer on rape yield, quality and utilization rate of fertilizer. [Result]The results showed that the yield of rape was increased by 1.25%~26.77% under 4 forms of nitrogen fertilizer combined with γ-PGA. With 4.3 mg/kg soil of γ-PGA, the synergistic effect was better under urea and combined application of organic and inorganic fertilizers. The contents of soluble sugar, soluble protein and free amino acid were increased by 49.60%, 23.62% and 132.79% respectively, and the nitrate content decreased by 6.18%~46.08%. The synergistic effect was better under ammonium chloride and combined application of organic and inorganic fertilizers. The utilization rates of nitrogen, phosphorus and potassium were increased by 0.63%~7.61%, 0.01%~1.66% and 0.78%~6.49% respectively. The utilization rates were higher under urea and combined application of organic and inorganic fertilizers. [Conclusion]In conclusion, according to the short-term pot experiment, γ-PGA combined with urea or organic-inorganic fertilizer was recommended in agricultural production, and the dosage of γ-PGA was 4.3 mg/kg soil.

Semi-automatic transplanter is the main type of transplanting machinery in China, its process of picking seedling needs to rely on casting seedlings by hand while planting by mechanical parts, which leads to high labor intensity and low production efficiency. The authors designed a picking up and delivering seedlings system for rape plug seedling, aiming to provide reference for designing a whole automatic rape seedling transplanting machine. The test bench was manufactured and the experiment was carried out. The results showed that, the seedling frequency had little effect on the lateral seedling feeding precision, and when the seedling frequency was 70 /min, the lateral error was ±1 mm, and the longitudinal seedling error was ±2 mm，the success rate of seedling pick-up was over 95%. The design can meet the application requirements.

[Objective]As one of the major oil crops, oilseed rape has an important position in the national economy. The fragmentation of rape planting in our country significantly increased the difficulty of monitoring its growing area, as the regular ground survey takes much time and energy with low representation.Remote sensing, with the features of covering large areas and revisiting in a high frequency, has become the most ideal method for monitoring rape growing area. The common remote sensing monitoring methods including visual interpretation and supervised classification are comparatively more influenced by the subjectivity of the monitors, due to the high degree of human-computer interaction.Aiming at the above problems; this article proposes a new monitoring method on the basis of unsupervised classification after layering. [Method]The GF images of the year 2013 in Jiang County have been adopted for application and precision evaluation by equidistance layering and natural layering. [Result]The result shows that the unsupervised classification after layering is higher in the overall precision than the direct unsupervised classification. The overall precisions on the basis of equidistance layering and natural layering increased from 79.16% to 84.44% and 85.17% respectively. The user precision in the direct unsupervised classification is only 72.97%. After equidistance layering and natural layering, the precision rate have been raised up to 81.05% and 86.12% respectively, leading to a great reduction of misjudging the non-rape area as the rape area. The overall precisions of equidistance layering and natural layering are 84.44% and 85.17%, with the Kappa coefficient to be 0.69 and 0.70. There is no significant difference in the precision between two layering methods. But the natural layering has a comparatively higher degree of user precision, mapping precision and overall precision with higher reliability.[Conclusion] The new methods proposed in this article has little manual intervention and high precision, which has a large potential to be applied in area monitoring on the basis of mass images.

The aim of the study is to investigate the relationship between quality traits of Brassica napus, and promote and improve the quality traits of rapeseed. One hundred and seventy DH lines were tested at field experiments in 2009-2012 years and corresponding to phenotypic data of seed quality traits were obtained for three consecutive years. Through phenotypic, correlation and principal component analysis to analyze quality traits data of DH lines. The results showed that: the variation coefficient of the erucic acid content was the highest between the female and male parent (up to 15.53%). The variation range of glucosinolate content in DH population was the largest and reached to 128.43μmol/g, but the variation range of saturated fatty acids was the smallest, and only 1.97%. The quality phenotypic variation in DH population showed a phenomenon of over parental inheritance. In addition to erucic acid, oil content showed a significant negative correlation with other quality traits, especially the negative correlation coefficient with protein content was the largest (-0.72). The protein content was extremely significant positive correlation with oleic acid, linoleic acid, linolenic acid and glucosinolate content, but it was extremely negatively correlation with oil content and erucic acid content. Except for protein content, other quality traits contents showed extremely significant or not significant negative correlation with glucosinolate content. The quality traits can be synthesized into oleic and linoleic acid factors, protein factor, linolenic acid factor and glucosinolate factor via principal component analysis, and the cumulative contribution rate reached to 93.94%, which basically reflects the comprehensive information of the quality traits in DH population of Brassica napus.

To screen pod shattering resistant varieties and to promote the mechanized production process of rapeseed (Brassica napus L.) in areas of early-maturing varieties, pod shattering resistance index (SRI) of 98 early-maturing Brassica napus L. materials was assessed with random impact test method. The testing results were analyzed by cluster analysis and correlation analysis in combining with related agronomic traits. The results showed that the coefficient of variation (CV) of SRI was 41.38%, and the materials with SRI≥0.4 accounted for 68.4%. The cluster analysis demonstrated that the 98 early-maturing Brassica napus L. materials were clustered into three groups: A, B, and C. The average SRI of group A was 0.35, presenting easy shattering. The average SRI of group B was 0.93, presenting high resistance to shattering. The average SRI of group C was 0.65, presenting moderate resistance. The correlation analysis with main agronomic traits showed that SRI had an extremely and significantly positive correlation with pod length and a significantly positive correlation with 1000-seed weight, indicating that pod length and 1000-seed weight significantly affected pod shattering resistance, and both the two indexes could be used in shattering resistance screening of Brassica napus L.. Finally, the test materials with SRI>0.4 were screened in terms of yield and oil content, and 10 materials which had higher SRI and 5% more yield increase compared with that of CK (‘HY8’) were screened out. The study could provide theoretical guidance for phenotypic identification, genetic analysis and molecular marker-assisted selection of pod shattering resistance in early-maturing Brassica napus L..

In order to increase the application value of rape polysaccharide, the optimization of rape polysaccharide extraction process was studied with cruciferous plants of the Brassica chinensis as the research object. The rape was dried, crushed, through 100 mesh sieve and degreased. Rape polysaccharide was extracted by hot water extraction according to the extraction time, extraction temperature, extraction water ratio and times of extraction on condition of single factor experiment. The extraction optimization conditions of rape polysaccharide were obtained by orthogonal experimental design. The yield of rape polysaccharide was 17.85% under the optimum condition for the single factor; the yield of rape polysaccharide was 19.18% under the orthogonal optimization optimal conditions. The optimum extraction conditions of rape polysaccharide showed that the water content was 40 (1 g: 40 mL), the extracting temperature was 100℃, the extracting time was 1.5 h, the number of extraction times was two.

Wheat and rape are the two important staple crops in China, their spatial pattern change draws wide attention. Area data of wheat and rape from 1980 to 2014 were used, provincial level administrative region was taken as the study unit, combined with the rivalrousness of similar growth cycle crops, the spatial pattern and its change of wheat and rape were studied by the method of Pearson correlation analysis and GIS spatial geometric center of gravity analysis. The results showed that: the change of spatial pattern of wheat in the past 30 years was not significant, but the provincial distribution was unbalanced, the distribution center of wheat was always located in Henan Province; the distribution center of rape was southward from Hubei since 1980, and it is now located in Hunan. Affected by the interspecific competition of crops with similar growth cycle, the area variation of rape and wheat in Shanxi, Qinghai, Hubei, Hunan and Sichuan showed a significant“growthdecline” relationship, which was significantly negative correlated with each other.

The development of Chinese oil crops industry during past decades was reviewed in this paper. The production of major oilseed, import and export trade of concerned products and increase of domestic consumption were analyzed. The science and technology innovation in the fields of oil crops genetic enhancement, high yield cultivation, plant protection, mechanization, product processing and quality management during the past fifty years and their roles in promoting the industry were assessed. Further goals, priorities and policy strategies for oil crops industry development were discussed and proposed.