Oilseed rape is the most widely cultivated oil crop in China. A systematic review of the production and utilization of oilseed rape straw resources in China is vital for extending the oilseed rape industry chain. Based on the crop straw resource ledger data of the Ministry of Agriculture and Rural Affairs and publications, we have conducted a systematic analysis of the base number and utilization status of oilseed rape straw resources in China. Moreover, suggestions for future development have been proposed. The results showed that in 2021, the production of oilseed rape straw in China was 29.147 million tons (excluding Hong Kong, Macao, and Taiwan Province of China), and the collectable amount was 23.684 million tons, following to the three major grain crops of maize, rice, and wheat. The fertilizer utilization of oilseed rape straw accounts for an absolute proportion of 63.9%, especially for directly return to the field of 51.4%. The potential of utilization for feed and energy was enormous, while the proportion of base material or raw material utilization was relatively low. In the future, it is necessary to strengthen the support of key technologies and equipment for returning to the field and feed utilization, and pay attention to the construction of policy systems to enhance the level of industrial development.
In order to facilitate the increase in national Camellia oleifera production, promote the high-quality development of the C. oleifera industry, and ensure national grain and oil security. Using the LMDI model to decompose the yield formula of C. oleifera, quantitatively calculate the contribution of unit yield and planting area to the production increase of C. oleifera during the "11th consecutive increase" period from 2010 to 2021, both at a national and from regional perspectives, and comprehensively explore the regional pattern and contributing factors of C. oleifera production increase in China. The results are as follows: Nationally, the production increase is dominated by the improvement of per unit yield; Regionally, the increase in the core production area is mainly due to the improvement of per unit yield with super-high speed, while the production increase in the active production area and general production area is mainly due to the expansion of plantation area, resulting in "lagging increase" and "synchronized increase" levels respectively. Among them, 6 provinces (autonomous regions, municipalities under the State Council) demonstrate higher contribution from increased per unit yield, while 8 provinces (autonomous regions, municipalities under the State Council) show higher contribution from expanded planting area. Hunan, Jiangxi, and Guangxi, which have increased production by over 200 000 tons each, constitute the core areas of C. oleifera production, accounting for 75.6% of the total increase nationwide. 6 provinces (autonomous regions, municipalities under the State Council), including Anhui, Hunan, Hainan, Chongqing, Sichuan, and Guizhou, have reached the level of super-high speed in terms of production increase. To conclude, the underlying causes of the explicit contributing factors to the production increase of C. oleifera were explored, the factors that constrain the development of the C. oleifera industry were summarized, and targeted suggestions were proposed.
Sunflower is considered one of the crucial oil crops, ranking only behind soybean, peanut and rapeseed on both area and yield in China. However its growth is manifestly stunted by broomrape with inadequate seed development, which was initially reported in Russia in 1866, sunflower broomrape proliferated extensively across sunflower-growing regions globally, leading substantial damage on sunflower production. To combat the prevalence of sunflower broomrape, researchers have focused on understanding its parasitic mechanisms, and also sunflower's defenses for better control. Romania researchers revealed evolutionary transition of sunflower broomrape from race A to I and beyond. The sustained evolution of sunflower broomrape's virulence stems from 2 primary factors. Firstly, sunflower broomrape's expansive seed bank provides ample material for mutations. Secondly, gene exchanges among populations, and wild species continually reshuffles their genome, enhancing population genetic diversity and hastening sunflower broomrape's virulence evolution. Most sunflower varieties exhibit vertical resistance to sunflower broomrape, which governed by a single dominant gene. Each resistance gene corresponds directly to an avirulence gene in sunflower broomrape, following the gene-for-gene interaction. While incorporating a single dominant gene expedites sunflower breeding for resistance, it remains rapidly overcome by new and more virulent race. Thus the future focus of resistance breeding might lean toward pyramiding multiple dominant genes or quantitative resistance genes. Researchers have devoted efforts to identify resistance genes, sourcing them from local, cultivated, and wild sunflower species. Identified genes to date include Or1-Or7, OrDEB2, and OrSII . Advances in DNA markers and sunflower genome refined mapping of these antagonistic genes. For instance, the OrDEB2 gene is located within a 0.9 cM-interval on chromosome 4's upper segment, corresponding to 1.38 Mb-genome section, with 9 candidate genes available for direct application on resistance. Sunflower's resistance to broomrape spans 3 stages: pre-attachment, pre-haustorial, and post-haustorial, each evolving distinct physical and chemical barriers to thwart parasitism. Leveraging sunflower's resistance mechanisms to cultivate diverse resilient varieties emerges as the most cost-effective method for crop control. Furthermore, preventive and control strategies encompass early prediction, agronomic practices, chemical and biological interventions. The synergistic use of these strategies yields optimal control outcomes. In summary, this paper provides an overview of sunflower broomrape seed germination mechanisms, parasitic process, domestic and global distribution of sunflower broomrape physiological races, sunflower's resistance mechanisms against broomrape, and the latest sunflower broomrape prevention and control technologies. Research on control technology of sunflower broomrape requires collaboration from multiple disciplines including plant pathology, pesticide science, and breeding. This will accelerate the development and improvement of control technologies for broomrape.
In recent years, due to the delayed harvest time of rice in China, the sowing date of rapeseed has been continuously postponed, making it more difficult for seeds to germinate under low temperatures. The main rapeseed production areas in the Yangtze River Basin often experience “cold spell in later spring” weather, which seriously endangers the flowering and pollination of rapeseed, reduces seed setting rate, and leads to a serious reduction in rapeseed production. The development of new rapeseed varieties that can quickly germinate under low temperature conditions and tolerate low temperature during flowering has become one of the key issues that urgently need to be solved for rapeseed production. Based on 49 early maturation breeding backbone resources screened previously, we further identified rapeseed germplasm that can germinate under 8℃ low-temperature in this study. The speed breeding growth chamber was employed to promote rapeseed flowering and a rapid method for assessing low temperature tolerance during flowering was established. Two new early maturation rapeseed varieties with low temperature tolerance both at flowering and germination stages were screened using this technology.
Our previous study revealed that BnaC3.CCD4 encodes carotenoid cleavage dioxygenas whose mutations altered flower color from white to yellow in rapeseed. Interestingly, we observed that the white flowers of functional BnaC3.CCD4 transgenic lines showed pale yellow in the morning and still became pure white in the afternoon during the daytime. In order to explore whether environmental signals such as light and temperature have a regulatory effect on carotenoid biosynthesis and metabolism, RNA-seq was performed for transcriptomic analysis on them at two different timepoints in the present research. The analysis results of gene ontology (GO) and kyoto encyclopedia of genes and genomes (KEGG) revealed that a number of differential expression genes were significantly enriched in pathways related to light signal, circadian rhythm, stimulus response and carotenoid biosynthesis et al. Through further analyzing the top 50 differentially expressed genes, it was revealed that the light signal might be the key factor for the flower color change of BnaC3.CCD4 transgenic lines. Therefore, it was inferred that the light signal factors potentially regulate the expressions of the genes in the carotenoid biosynthesis pathway by binding to their photoresponsive elements to control the carotenoid contents in the petals and then cause their color change.
Rapeseed production is severely restricted by Sclerotinia disease. Elongator complex protein (ELP) is a 6-subunit complex that interacts with RNA polymerase II, involved in plant defense response. To deeply understand its gene function, we constructed vectors on overexpressed-BnA06.ELP2 and knockout-BnA06.ELP2 (by gene editing) using homologous recombination method, and then investigated their transgenic plants. Disease resistance experiments showed that BnA06.ELP2 overexpression plants exhibited better resistance compared to wild-type, while gene edited BnA06.ELP2 plants led to a decrease of resistance. Further RT-qPCR analysis indicated that BnA06.ELP2 could regulate transcription of catalase BnCAT1 and BnCAT2 (marker genes of JA/ET pathway), jasmonate synthesis related genes BnLOX2 and BnOPR1, and BnPDF1. These results indicated that BnA06. ELP2 function in rapeseed is involved in defense response against Sclerotinia sclerotiorum infection.
To facilitate the screening of excellent peanut germplasm, 25 small-pod peanut varieties were used to genetic diversity analysis based on 18 phenotypic traits. Results revealed that the 25 small-pod peanuts had abundant genetic diversity, and the highest Shannon-Wiener diversity index among quality traits was leaf shape (0.95), the highest Shannon-Wiener diversity index among quantitative traits was productivity per plant (1.959), and the highest coefficient of variation was the number of full pods per plant (46.421%). Results of factor analysis indicated that cumulative contribution rate of the first 3 main factors extracted was 80.506%. The first factor mainly reflected peanut yield traits, such as 100-pod weight and 100-seed weight. The second factor mainly represented the yield components such as total branche number, branche number with pods, full pod number and the productivity per plant. The third factor mainly reflected the plant height. The 25 small-pod peanuts were divided into 3 groups by cluster analysis. The Group Ⅰ included varieties with higher main stems, longer lateral branches and greater potential for yield increase. The Group Ⅱ included varieties with coordinated growth of main characteristics and better stable yield. The Group Ⅲ included varieties with relatively single excellent characteristics. By calculating the comprehensive score of peanut varieties, the highest score was of Jihua 10, and the lowest was of Jihua 8.
To improve peanut breeding, we comprehensively analyzed the main agronomic traits, yield, quality and disease resistance of peanut varieties registered in China from 2017 to 2022. Results showed that totaly 1168 varieties were registered during this period, among them 85.6% were by crossbreeding, and common type was the dominant. Scientific research institutes are the leading force in peanut breeding. By analyzing their parents, it was found that 9 varieties were the backbones for up to 300 varieties. The backbone parents included Kaixuan 01-6, Baisha 1016 and Yuhua 15. Pod number per plant and oleic acid content of the registered increased each year, while linoleic acid content and resistance showed significantly decrease. Yield and other traits remained relatively stable with minor variations. Correlation analysis showed that dry pod yield and kernel yield were both significantly positively correlated with total branching number, number of branches with pod, pod weight, kernel weight and oil content. And, they were significantly negatively correlated with main stem height, lateral branch length, and protein content, indicating that yield could be improved by increasing branch number and appropriately reducing main stem height. Synergistic relationship between yield and quality provided possibility for peanut breeding with high yield, high oil and high oleic acid.
To identify the members of Oleosin gene family and analyze its structure and function, Hiddne Markov Model (HMM) was used to search the protein databases of wild peanut (Arachis duranensis) and (Arachis ipaensis). The bioinformatic method was carried out to predict and analyse the physicochemical properties,gene structure,and gene location. The expression patterns of these genes in different peanut tissues and organs and under different stress conditions were analyzed by qRT-PCR. In this study a total of 7 AdOleosin genes and 6 AiOleosin genes were identified. Results showed that all Oleosin genes except Aiole-2 are acidic proteins. Further analysis showed that Oleosins were basic small molecular proteins with α-spiral as the main structure. They have 2-3 transmembrane domains, a conserved central hydrophobic region and a highly conserved proline junction. The AdOleosin and AiOleosin gene families have similar chromosomal localization, which no localization on chromosomes 1 and 6, and 3 family members each on chromosomes 4 and 7. There are multiple hormone and stress-related cis-acting elements, indicating that the gene family is involved in stress response. Further, the expression patterns in different tissues were investigated by qRT-PCR. Results showed that the Oleosin gene expressed in peanut seeds is temperature dependent and expression in peanut roots, stems, leaves were induced by drought stress, salt and ABA. The above results provide a theoretical basis for in-depth study of the gene function of the Oleosin family.
In order to solve the problems of large number of soybean germplasm resources，heavy renewal burden and low breeding efficiency for fine varieties in Shanxi, the genetic diversity of 20 phenotypic traits for 1999 soybean germplasm resources was used to establish a core germplasm collection. Unweighted pair-group method with arithmetic means was used to construct core germplasm by randomly sampling the resources in each region after systematic clustering. The core germplasm retained 10.66% of the total number of original germplasm. The representativeness of the established core collection was comprehensively tested by both multiple characteristic values (minimum, maximum, mean, standard deviation, coefficient of variation, and diversity index) and evaluation parameters (percentage of mean difference, percentage of variance difference, range coincidence rate, variable rate of coefficient of variation, and phenotypic retention ratio). The results indicated that the t-test results of diversity index of 19 phenotypic traits between core germplasm and original germplasm were not significant, and the percentage of mean difference, range coincidence rate, variation rate of coefficient of variation and variance difference were 0, 136.29%, 106.44% and 15.79%, respectively. The first 7 principal components of core germplasm and original germplasm were the same, and the cumulative contribution rate was 85.761% and 85.857%, respectively. The results demonstrated that a total of 213 core germplasm resources effectively represented the genetic diversity of Shanxi soybean local varieties.
To establish a simple and efficient method of salt tolerance assessment in sunflower, clarify the difference in salt tolerance among different genotypes of sunflower and select the highly salt-tolerant cultivars, in this study, the seeds and seedlings from 20 sunflower varieties were subjected to different concentrations of NaCl salt solutions, then the changes of every index for each variety were observed under different treatments and time points, and correlation, principal component, membership function value, cluster analysis and comprehensive evaluation of salt tolerance were conducted based on each index to compare the salt tolerance of those varieties. The results showed that seed germination and seedling height of some varieties had a certain promotion effect under the treatments with the NaCl concentration below 160 mmol/L compared to the control. However, with the increase of concentration and the delay of treatment time, seed germination and seedling growth were inhibited to different degrees and the suppression was more obvious. Under NaCl treatment, K+/Na+ of seedling leaves was significantly higher than that of root, and the relative SPAD value initially increased and then decreased with the increase of NaCl concentration. Under the same stress concentration, the relative values of each observed index of salt-tolerant varieties (compared with 0 mmol/L control) exhibited higher than those of salt-sensitive varieties, indicating that salt-tolerant varieties were less affected by NaCl compare to salt-sensitive ones, and had a certain salt tolerance. It was concluded that the optimal concentration for NaCl salt tolerance identification in both sunflower germination and seedling stages was 250 mmol/L. The salt tolerance at the germination stage was compared by investigating the comprehensive membership function values of relative germination rate, relative germination potential, relative radicle length and relative germ length; Salt tolerance of seedlings was determined on the 14 day after NaCl treatment (250 mmol/L), by examining the comprehensive membership function values of relative survival rate, relative leaf area, relative plant height, relative SPAD value, relative fresh weight of above-ground tissues and relative fresh weight of roots. Two varieties No.67 and HZ001 with salt tolerance were obtained by the above method.
In order to investigate the appropriate fertilizing periods for no-tillage aerial-sowing mode of oilseed rape with complete rice straw incorporation in the rice-oil cropping system in the Yangtze River Basin, 4 consecutive field experiments were conducted in Wuxue and Huangpi City of Hubei Province in the years 2020/2021 and 2021/2022. 7 treatments were set up in the experiment, with no fertilizer treatment as control. Fertilizing periods of the other treatments were 3, 5, 7, 9, 12 and 17 days after sowing, respectively. The optimal fertilizing periods for no-tillage aerial-sowing oilseed rape were determined by investigation of agronomic traits in reproductive period, and also rapeseed yield and its components at maturity period, and by calculation of nutrient uptake of the aboveground parts. Results indicated that fertilizing periods significantly affected agronomic traits. When fertilized within 5 days after sowing, the average of density, plant height, stem thickness, and maximum leaf area during the overwintering period of the fertility phase increased by 43.2%, 18.2%, 13.9%, and 37.3% than other 5 treatments respectively. Fertilizer application significantly increased rapeseed yield, and the average yield of all fertilizer treatments was 3.57 times higher than that of control (no fertilizer treatment). In the two-point trials in 2020/2021, rapeseed yield reached the highest when fertilizer was applied within 5 days after sowing, resulting in an average yield increase of 27.5% compared with the others. The two-point trials in 2021/2022, rapeseed yield was the highest when fertilized within 7 days after sowing, having 33.8% increase over the other treatments. Fertilizing periods significantly affected the harvest density and siliques per plant. Compared with fertilizer application within 5 days after sowing, the average harvest density of the other treatments was reduced by 19.9%, and the average siliques per plant were reduced by 16.9%. Fertilizing periods significantly affected the contribution rate of fertilizer and nutrient accumulation, and their impact on yield in oilseed rape cultivation. In a series of two-year experiments, the highest contribution rate of fertilizer to yield and the accumulation of nitrogen (N), phosphorus (P) and potassium (K) in the aboveground plant occurred within 5 days after sowing. During this period, the average fertilizer contribution rate increased by 16.2%, and the accumulation of nitrogen, phosphorus and potassium increased by 19.2%, 32.3% and 34.5%, respectively, compared with the other treatments. In summary, the suitable fertilizing periods for no-tillage aerial-sowing oilseed rape is within 7 days after sowing, with the best timing being around 5 days after sowing. Delaying the fertilizing periods hinders the growth and development of oilseed rape populations and individuals by restricting nutrient absorption of oilseed rape, which reduces the yield of oilseed rape.
Without shattering resistance and different pods ripen time of indefinite inflorescence in rapeseed maturating stage, combine harvest usually result to more than 20% of rapeseed yield loss in China. In order to reduce rapeseed combine harvest loss, we used two kinds of Diquat dibromide monohydrate (C12H14BrN2O) as desiccant in rapeseed maturating stage, to analysis effect of Diquate for desiccating efficiency and yield. The results showed that the moisture content of the sample pods and stems were decreased significantly which compared with the natural maturity after spraying diquat (“Reglone” from Syngenta and “Linongshou” from LuBachem). After spraying for 5 d with Syngenta Diquatand LuBachem Diquat, the moisture content of the pod decreased from about 45% to 9.58% and 16.05%, and the moisture content of the stem decreased from about 55% to 37.14% and 45.02%, respectively. Compared with LuBachem Diquat, Syngenta Diquat showed better fast and stable characteristics in raining weather. The suitable period of spraying Diquat were maturity stage of 80% pod color become yellow (in mid maturity), the yield increased by 9.69% and 4.15% compared with natural maturity combined harvest, and the average combine harvest loss rate were 4.63% and 9.45% which spraying Syngenta Diquat and LuBachem Diquat. Spraying Diquat in later stage of 100% pod color become yellow (in late maturity) lead to a significant increase harvest loss rate in 13.80% and 15.87%, respectively. Syngenta Diquat concentration of 9-45 g/hm2 and LuBachem Diquat of 9-27 g/hm2 didn't have influence with the descendant yield, while the high concentration (36 g/hm2,45 g/hm2) of LuBachem Diquat decrease descendant yield by 5.76% and 8.69%. Diquat didn't affect Erucic acid, Oleic acid, Glucosinolate, water content, germination potential and germination rate of seeds. As Diquat were registered as a desiccant plant growth regulation in China and other country with studies showed a strong safety, we suggest that Diquat maybe an increasing efficiency method to reduce harvest loss in rapeseed production in China and it has positive significance for improving rapeseed yield and production efficiency.
Developing vegetable and oilseed rape is an important multifunctional utilization of this crop. To better understand the application impact of follow-up nitrogen (N) fertilizer on stalk-free and stalk-cut rapeseed field on yield and its components, field experiments were carried out in Honghu City and Wuxue City, Hubei Province in 2022-2023. Main treatment was set as stalk-free and stalk-cut, secondary treatment was fertilizers (N) as 0, 22.5, 45.0, 67.5, 90.0 and 112.5 kg/hm2. Under the conditions of (Fresh) stalk harvesting of 6217 kg/hm2 and 6613 kg/hm2 respectievely in Honghu and Wuxue sites, seed yields were average reduced by 5.0% and 24.7%, compared to stalk-free. Among them, yields from the no- and low-adopted treatments were higher than those of the medium- and high-adopted treatments. Follow-up N fertilizer application during the shoot stage significantly increased seed yield of stalk-cut, and its response degree to N application was higher than that of stalk-free. The highest yields were obtained when 40.6 kg/hm2 and 42.2 kg/hm2 of follow-up N fertilizer were applied with stalk-free and stalk-cut respectively at Honghu site, while the corresponding optimal application of follow-up N fertilizer at Wuxue were 33.4 kg/hm2 and 40.3 kg/hm2. It indicated that the N amount applied to vegetable and oilseed rape with stalk-cut was higher than that of the general. Follow-up N fertilizer increased the number of siliques on the primary meristem of stalk-free rapeseed, and the number of siliques on the secondary meristem of stalk-cut rape. Stalk-cut significantly increased the number of seeds per silique but decreased thousand seeds weight. Oil content of stalk-cut was slightly higher and the application of follow-up N fertilizer could reduce the oil content of rapeseed, and improve oil production when follow-up N fertilizer application was suitable. These results indicated that under the condition of about 6.4 t/hm² of stalk cutting during shoot stage, no matter whether follow-up N fertilizer is applied or not will significantly reduce rapeseed yield, and the application of follow-up N fertilizer could make up for the yield loss. And the suitable amount of N fertilizer is about 40.0 kg/hm².
This study aimed to investigate the critical periods of cadmium (Cd) accumulation in peanut kernels and the dynamics of Cd absorption throughout peanut growth. Three peanut varieties, namely Huayu 22, Xianghua 2008 and Yueyou 43, were selected for field experiment. This study investigated the dynamic changes in Cd concentration in different organs of peanuts and its transfer coefficients at various growth stages, and differences among the varieties. Results revealed that over 69% of Cd in peanut kernels came from the early pod-setting stage to the early pod-filling stage, coinciding with kernel biomass indeased. Cd absorption peak occurred at the mid pod-setting stage but sharply decreased in the early pod filling stage. Peanut roots efficiently absorbed and transported Cd to above ground parts, with transfer coefficients peaking at flowering stage, then gradually declining but maintaining relatively high level (TF > 1). Cd transfer from aboveground parts to pods was relatively inefficient (TF ≤ 0.2) during whole reproductive growth stage. However, Cd transfer from pod shells to kernels was efficient, peaking at early pod filling stage and then remaining stable or slightly decreasing. Most absorbed Cd was allocated to stems and leaves, accounting over 80% of the total Cd accumulation. Lower Cd accumulation in Huayu 22 kernels was attributed to vigorous stem and leaf growth and a relative lower translocation factor from shell to kernel compared to other two varieties. Reducing Cd absorption from soil, minimizing Cd transfer from the aboveground parts to pods during the reproductive growth stage, particularly after the early pod-setting stage, and restricting Cd transfer from pod shells to kernels from early pod-setting to early pod-filling stage are crucial for safe peanut production.
To systematically solve the problems in the production of peanut, such as scattered planting, low emergence rate, and difficult emergence of the first pair of lateral branches, the 'Twice Compaction' cultivation technique was developed. In order to evaluate the effect of this technique on peanut cotyledon node excavation and yield increase, Huayu 25 （HY25） and Huayu 36 （HY36） were selected as experimental materials. Three treatments including Control （CK）, Cleaning stem base soil （QK）, and Twice compaction （ZY） were set up to investigate the effects on the emergence rate, strong seedling rate, cotyledon node extraction rate, agronomic traits, dry matter accumulation, yield composition and quality of different peanut varieties. The results demonstrated that both QK and ZY were beneficial to seedling growth, however ZY significantly improved the emergence rate and cotyledon node extraction rate of peanut, leading to a further improvement in strong seedling rate compared to QK. Specitically, ZY increased the seedling strength rate of HY25 and HY36 by 13.1% and 12.4%, respectively. ZY has more significant regulatory effect on HY25, which has a lower rate of native cotyledon node emergence. ZY could reduce main stem height and lateral branch length, promote root development, and increase the number of green leaves and leaf area index of main stem at maturity. Moreover ZY promote fruiting and full pod, increase the proportion of dry matter distribution to pod, increase economic coefficient and the number of harvested plants, and finally increase pod yield significantly, meanwhile increase the oil content and O/L value of peanut kernels to improve peanut quality. In summary, the "Twice compaction" cultivation technique is conducive to improving the emergence rate, strong seedling rate, and cotyledon node emergence rate of peanut, improving agronomic traits, promoting dry matter accumulation and the proportion of distribution to pod, increasing yield and improving quality. It provides a theoretical basis and technical support for the light, simple and efficient cultivation technique in peanut production.
In order to explore the effects of peanut/maize intercropping system on the occurrence of two speices of important agricultural pests, Holotrichia parallela and Anomala corpulenta,the oviposition selectivity of these two scarab species between maize and peanut was studied under three conditions (i.e., mesh-covered cultivation pool, net house and open field), and the effects of peanut/maize intercropping on the occurrence of the two species of scarab larvae were discussed. The results revealed that H. parallela represented obvious oviposition preference for peanut and A. corpulenta hada certain degree of oviposition preference for maize. The larval population density of H. parallela in peanut monoculture area is 3.55-6.59 times that in maize monoculture area; however, there was no significant difference in larval population density of A. corpulenta between the two monoculture areas. In the peanut/maize intercropping system, the population density of the H. parallela larvae in the whole intercropping area and the peanut plot decreased by 43.38%-70.84% and 33.55%-54.33%, respectively, compared with that in peanut monocropping area. Meanwhile, the average larval population density of A. corpulenta in peanut and maize monoculture areas was slightly different from that in peanut and maize monoculture areas, but there was no statistically significant difference. In summary, the peanut/maize intercropping system can significantly reduce the population of the H. parallela larvae, while it has no significant impact on the A corpulenta larvae.
For guiding the precise control of peanut thrips in China, differences were observed on dominant species of peanut thrips across different peanut-producing regions. The investigation and identification of peanut thrips, based on plant-flapping and color-trapping methods, were implemented in 6 representative regions. Diversity and similarity of thrips communities were analyzed. Hierarchical cluster analysis based on species composition structure was carried out. Results revealed that a total of 14 234 thrips were collected from all sampling sites (Urumqi in Xinjiang, Gongzhuling in Jilin, Fenyang in Shanxi, Qingdao in Shandong, Quanzhou in Fujian, and Zhanjiang in Guangdong), belonging to 10 species, 6 genera and 3 families. In terms of genera/species composition, the proportion of genera/species in the family of Thripsidae is the largest. Overall, Frankliniella intonsa/ F. occidentalis, Thrips tabaci, Megalurothrips usitatus and Anaphothrips obscurus are the main species of thrips in peanut fields. Shannon-Wiener diversity index of thrips communities in the different regions could be ranked as: Qingdao> Urumqi> Quanzhou> Gongzhuling> Zhanjiang> Fenyang; and Simpson dominance index as: Zhanjiang> Fenyang> Gongzhuling> Quanzhou> Urumqi> Qingdao. The Jaccard similarity coefficient between the 2 thrips communities ranged from 0.40 to 1.00, representing medium dissimilarity, medium similarity and extremely similarity, and medium similarity was in the majority. The 6 regions were obviously clustered into 2 categories: northern production regions and southern production regions. In the 4 northern regions, the dominant species were F. intonsa/ F. occidentalis and T. tabaci, which accounted for 35.72% to 40.35% and 15.20% to 56.55%, respectively. M. usitatus were the dominant species in the 2 southern regions, accounting for 31.09% to 74.32%. F. intonsa/F. occidentalis and M. usitatus occurred throughout the growth period of peanut, while T. tabaci occurred mostly in the early or early middle stages. A. obscurus, rarely studied on peanuts, occurred in large numbers and steadily in both northern and southern China, with potential risks of harming peanuts. In addition, it was found that different survey methods had influence on both the number and proportion of thrips species.
Soybean rust caused by Phakopsora pachyrhizi, is a significant disease of soybean in tropical and subtropical regions, and results in serious soybean yield reduction. To futher understand the pathogen infection process, safranin fast green, DAPI (4',6-diamidino-2-phenylindole), calcofluorescent White (CFW) and WGA488 (wheat germ agglutinin, Alexa FluorTM 488 conjugate) staining were used to observe the rust pathogen infection process. The results indicated that safranin-fast green staining facilitated the distinct visualization of the layout of mesophyll tissue, spore pile, and newly-formed urediospores; DAPI staining can be employed to visualize the status of nuclei; CFW could distinguish the hyphae from plant tissue, facilitating the observation of spore invasion and hyphal distribution in mesophyll tissue; WGA488 dye is exclusively applicable for staining fungi and is suitable for assessing the integrity and coherence of hyphae formation in mesophyll tissue. Choosing appropriate staining methods is crucial for accurately understanding the microscopic structure and infection process of soybean rust in accordance with research needs.
To investigate the impact of synthetic bacterial flora of nodule endophytes on soybean growth and root microorganisms, this experiment used nodule endophytes isolated from soybean root nodules to construct four synthetic bacterial flora by complementation of strain functions, increase in diversity and superposition of growth-promoting effects. In the study, the bacterial groups Q1 and Q4 exhibited the best growth-promoting effects. Q1 significantly enhanced the stem length, stem fresh weight, root fresh weight and nodule number of soybean plants, increasing by 19.2%, 44.0%, 51.7% and 140.0% respectively. Q4 significantly increased the total root length, root surface area, root fresh weight and number of nodules of soybean plants, increasing by 24.3%, 34.0%, 40.0% and 200.0% respectively. The 16S rRNA sequencing results in the roots revealed that Bacillus and Klebsiella among the root nodule endophytes invaded soybean roots, increased the positive correlation among bacterial communities and the abundance of genes encoding genes related to ecological functions. Metagenomic sequencing results of rhizosphere soil showed that after inoculation with synthetic bacterial flora, beneficial bacterial genera such as Nocardioides and Pseudonocardia were enriched in the rhizosphere, and genes involved in nitrogen metabolism and indole-3-acetic acid （IAA） biosynthetic pathways were significantly increased, and rhizosphere bacteria to carry out biological processes such as coenzymes, amino acid transport and metabolism, carbohydrate metabolism and signal transduction were promoted. The results provided theoretical basis and technical support for the construction of soybean endophytic microbiome and the development of efficient microbial fertilizer.
To understand the biological characteristics of teliospores and aeciospores of P. helianthi, this study investigated the optimal germination conditions for these two types of spores. The results revealed that the collected fresh teliospore could only germinate after being stored at room temperature for more than 180 days. Storage at -20℃ had a better germination effect, with a germination rate of 39.45% after 180 days, however by 420 days, the activity of teliospores was basically lost. Teliospores could germinate on water agar medium at 15℃ for 12 hours, reaching a peak germination rate of 31.89% after 48 hours. Aeciospores began to germinate on water agar medium at 20℃ within 2 hours, and reached the highest (54.33%) after 24 hours. The concentration of water agar medium had no effect on the germination of teliospores, but 0.50% agar medium was most suitable for the germination of aeciospores. The conditions of 15℃ and pH 6 were favorable for the germination of teliospores; 20℃ and pH 7 were the most suitable for the germination of aeciospores. Light had no effect on the germination of teliospores but promoted the germination of aeciospores. A low concentration (10 g/L) of leaf extract could promote the germination of both types of spores, while a high concentration inhibited them.
To investigate the effects of different concentrations of thiamethoxam on the infestation ability of the parental and first filial generation populations of R. pedestris on soybean, the adults and nymphs of R. pedestris were treated with thiamethoxam to establish experimental parental and first filial generations under different concentrations of thiamethoxam. At the full pod stage of soybean (R4), we used the potted soybean with netting and then inoculated the parental and first filial generation populations of R. pedestris treated with different concentrations of thiamethoxam, and studied the effect of their damage on soybean plant yield. The results showed that in the same generation and insect stage, the infestation ability of each treatment population decreased with increasing thiamethoxam concentration. Under the LC50 concentration treatment, the soybean yield of the parental adult and nymph treatments was 1.97 and 1.78 times higher than that of the control treatment, and the yield of the first filial generation was 1.71 and 1.44 times higher, respectively. The infestation ability of parental adults and nymphs in the control (LC0) treatment was 2.62 and 3.12 times higher,respectively, than that in the LC50 concentration treatment. Similarly, the first filial generation was 1.68 and 1.61 times higher than that of the LC50 treatment, respectively. In the same concentration treatment, soybean yield after parental infestation was greater than that after infestation by the first filial generation. Soybean yield after parental nymph infestation was the highest, while soybean yield after the first filial generation adult infestation was the lowest. This indicates that the first filial generation of R. pedestris treated with thiamethoxam still has some adverse effect on soybean yield, but this effect gradually decreases. The infestation ability of the first filial generation was higher than that of the parental treatment, and the infestation ability of both the parental and first filial generation treatments showed a decreasing trend with increasing concentration. The regression model of infestation ability was as follows: adult-parental generation generation: y=63.460-0.484x; adult-first filial generation generation: y=65.048-0.327x; nymph-parental generation generation: y=48.211-1.422x+0.0167x 2; nymph-first filial generation generation: y=55.068-0.884x+0.00888x 2. Different concentrations of thiamethoxam-treated soybeans resulted in some yield loss. Under the same concentration treatment, the infestation ability of the first filial generation was greater than that of the parents and the infestation ability of both the parental and first filial generatio decreased with increasing concentration. The infestation ability of the adults was greater than that of the nymphs and decreased with increasing concentration. The test results provide a basis for a rational and scientific reduction in the use of thiamethoxam in the field for the control of R. pedestris.
For high efficient rapeseed quality detection, a method was developed on low-cost and time-efficient detecting chlorophyll content in rapeseed. In this method, extraction of chlorophyll from seed samples was achieved using ethanol (95%), followed by development with petroleum ether (60-90℃)-acetone-toluene (2:1.5:2, volume ratio). Chlorophyll fluorescence color was excited using a UV analyzer (365 nm). Fluorescent spot image was captured using a smartphone. Image J software was employed for automatic identification of fluorescent spots, measurement of spot area, and realization of rapid qualitative and quantitative analysis of chlorophyll a and chlorophyll b. The linear range for chlorophyll a and b was determined to be 0.04-1.00 mg/mL, with R2 of 0.9965 for chlorophyll a and 0.9925 for chlorophyll b. The intra-day precision was 5.9% for chlorophyll a and 6.1% for chlorophyll b, while the inter-day precision was 8.6% for chlorophyll a and 5.6% for chlorophyll b. The recoveries of chlorophyll a and b in rapeseed were observed to be between 90.00% and 91.67% for chlorophyll a, and between 92.00% and 113.00% for chlorophyll b. These results indicated the well linearity and accuracy of this method, enabling rapid determination of chlorophyll content in rapeseed.
In this study, recombinant inbred line populations were used to establish a rapid near-infrared spectroscopy method for determining sucrose content with a wide detection range and suitable for screening excellent individual plants. This study used high performance liquid chromatography combined with differential refractive index technology to determine the sucrose content of 325 materials. The near-infrared spectra were collected using a Perten DA7200 near-infrared analyzer, and a near-infrared prediction model for sucrose content on small sample cup with 18-23 peanut kernels was constructed using partial least squares method. The results showed that the prediction range of the model for sucrose content in peanut kernels was 2.07%~12.37%, with a determination coefficient of 0.9054 and a root mean square error of 0.6774. The model was externally validated using 20 materials, and the independent test set decision coefficient was 0.9478. This model predicts the sucrose content of peanut kernels accurately, which can achieve rapid and non-destructive determination of sucrose content per plant in early hybrid generations, and improve the breeding efficiency of high sucrose content peanut varieties.
To explore the effects of different additives on fermentation quality, nutrient quality and vitamin of mixed silage of alfalfa and rape straw, silage was made from a 5:5 mixture of alfalfa (Gannong 6) and locally harvested rapeseed straw at carob maturity. The experiment was set up with four groups of treatments: Control group CK (added distilled water); Enterococcus faecalis lactate Group I (E. feecelis); Lactobacillus plantarum Group II (L. piantarum); Enterococcus faecalis lactate + Lactobacillus plantarum Group Ⅲ. After silage for 60 days, the nutritional quality, fermentation quality and vitamin content were determined. The results showed that the addition of different lactic acid bacteria additives could increase the content of lactic acid (LA) in silage and decrease the pH value, among which the treatment of Group II had the lowest pH, which was significantly lower than that of Group I and CK group (P<0.05), and the lowest ammoniacal nitrogen/total nitrogen (NH3-N/Total nitrogen, NH3-N/TN), which was significantly lower than the control group (P<0.05). Water soluble carbohydrate content in Group Ⅱ was higher than that in other groups CK. The content of vitamin E in Group Ⅲ was the highest. Group I had the highest vitamin C content. Grey correlation degree analysis showed that the comprehensive performance of Group Ⅱ was the best. In conclusion, the fermentation quality of silage can be improved by adding lactic acid bacteria additives, among which Lactobacillus plantarum additive has the best comprehensive performance and is suitable for mixing alfalfa and rape straw silage.
