Phytochemical Study and Anti-nutritional Factors in Stems of Dioscorea praehensilis Benth(Dioscoreaceae)

The aim of this research was to find and assay phytochemical compounds and various biological macromolecules of the tender stems of Dioscorea praehensilis benth and evaluate their antioxidant activity and to compare the content of oxalates and cyanogenetic glucosides between raw and cooked tender stems.The plant collection and identification,phytochemical evaluation:phytochemical screening,preliminary(qualitative)analyses and in vitro assays.Phytochemical screening was performed by qualitative methods.The estimation of the content of secondary metabolites was evaluated by spectrophotometry-UV.Antioxidant activity was evaluated using the ABTS and DPPH assays and preliminary composition by the gravimetric method.The results obtained show that the stems of Dioscorea praehensilis are devoid of certain important chemical groups,the flavonoids were not detected and they were rich in total polyphenols(17.22±0.16),tannins(19.32±0.52)and anthocyanins(25.22±0.04).Our extracts showed a lower antioxidant activity than that of positive controls.The samples are rich in carbohydrates and fiber,with low levels of proteins,lipids and ash.Dioscorea praehensilis has a high toxicity in HCN,but after a good cooking of about 1 hour,99.97%of the cyanide are eliminated and does not have many oxalates.The results obtained show that Dioscorea praehensilis has a high dietary value and can therefore be used as a nutritive food.

Effects of Abiotic Environmental Factors on Soybean Cyst Nematode

As a pest, in order to complete its life history and reproduces effectively, soybean cyst nematode （SCN） （Heterodera glycines Ichinche 1952） must adapt to various environments and conditions for long periods of evolution. The nematode is widely dispersed year after year. Controlling this pest requires understanding characters and adaptability of SCN. Effects of abiotic factors, such as temperature, soil humidity, agrotype, pH value, ions, plant exudates, agricultural chemical and cultivation systems on SCN, are reviewed in this paper. The results show that SCN is able to endure various environmental stresses, especially low temperature. Because of its special life history, cyst stage help SCN over winter, resistance of SCN to environmental stress is strong. A few studies have reported the mechanism of SCN environmental adaptability. We emphasized the importance of studying environmental adaptability of SCN, which would benefit the control of SCN by ecological means.

Spatial differences in soybean bioactive components across China and their influence by weather factors

Bioactive components are partially responsible for the nutritional and health benefits of soybeans. Four major bioactive components: isoflavones, oligosaccharides, phospholipids,and saponins, were quantified in 763 soybean samples collected from widely distributed regions across China from 2010 to 2013. A majority of the tested bioactive components showed generally declining trends from the north(high latitude) to the south(low latitude).A positive relationship between total oligosaccharides(TO) and altitude was observed. Total isoflavones(TI), phospholipids(TP) and TO were negatively correlated with cumulative temperature above or equal to 15 °C(AT15) and mean daily temperature(MDT), but positively correlated with diurnal temperature range(DTR) and hours of sunshine(HS).Total saponins(TS) were negatively correlated with MDT but positively correlated with rainfall(RF), whereas TO were negatively correlated with RF. Path-coefficient analysis showed that, besides genotype differences, temperature and HS during the reproductive period influenced TI and TP contents, while temperature and RF influenced TS and TO. The effects of weather factors on soybean bioactive components in diverse regions of China were characterized. These findings will be helpful in promoting soybean production for functional food purposes.

Wild soybean(Glycine soja)transcription factor GsWRKY40 plays positive roles in plant salt tolerance

Wild soybean(Glycine soja),a relative of cultivated soybean,shows high adaptability to adverse environmental conditions.We identified and characterized a wild soybean transcription factor gene,GsWRKY40,that promotes plant salt stress.GsWRKY40 was highly expressed in wild soybean roots and was up-regulated by salt treatment.GsWRKY40 was localized in nucleus and demonstrated DNA-binding activities but without transcriptional activation.Mutation and overexpression of GsWRKY40 altered salt tolerance of Arabidopsis plants.To understand the molecular mechanism of GsWRKY40 in regulating plant salt resistance,we screened a cDNA library and identified a GsWRKY40 interacting protein GsbHLH92 by using yeast two-hybrid approach.The physical interaction of GsWRKY40 and GsbHLH92 was confirmed by co-immunoprecipitation(co-IP),GST pull-down,and bimolecular fluorescence complementation(BiFC)techniques.Intriguingly,co-overexpression of GsWRKY40 and GsbHLH92 resulted in higher salt tolerance and lower ROS levels than overexpression of GsWRKY40 or GsbHLH92 in composite soybean plants,suggesting that GsWRKY40 and GsbHLH92 may synergistically regulate plant salt resistance through inhibiting ROS production.qRT-PCR data indicated that the expression level of GmSPOD1 gene encoding peroxidase was cooperatively regulated by GsWRKY40 and GsbHLH92,which was confirmed by using a dual luciferase report system and yeast one-hybrid experiment.Our study reveals a pathway that GsWRKY40 and GsbHLH92 collaboratively up-regulate plant salt resistance through impeding GmSPOD1 expression and reducing ROS levels,providing a novel perspective on the regulatory mechanisms underlying plant tolerance to abiotic stresses.

Studies on the Correlations Between Isoflavone Contents in Soybean Seed and the Eco-Physiological Factors

The soybean cultivar Yudou25 was sown at 5 locations of Henan Province on 13 differentdates in 2001 and 2002. The data of isoflavone contents for the 109 samples of soybeanseed and 33 eco-physiological factors including meteorological factors, soil nutritionand altitudes were received and used for statistical analysis. The step-wise regressionwas used to screen the correlated factors, which significantly effected isoflavonecontents. Results showed that 9 eco-physiological factors were highly correlated withisoflavones. Low mean temperature, high diurnal temperature range at seed filling andmaturity, more sunlight hours and low mean temperature at emergence were favorable toisoflavone accumulation. The rainfall at emergence showed a nonlinear relationship withisoflavone content and its optimum value was 75 mm for isoflavone formation. Low diurnaltemperature range at branching, high organic matter and low sulfur content in soil weresuitable for the formation of isoflavones. The isoflavone contents would not be affectedby other eco-physiological factors in this study.

Anti-nutritional characteristics and mechanism of soybean agglutinin

Soybean agglutinin(SBA)is an important anti-nutritional factor in soybean.SBA can induce animal growth inhibition,cause pathological changes of intestinal tissue,and decrease in the immune system functioning.Recently,a great deal of research has been done on the effects of SBA on cell morphology,division,apoptosis,autophagy,as well as the correlated signal transduction pathway.This review mainly covers the chemical and biological characteristics of SBA,describes the multifaceted aspects of SBA anti-nutritional functions,and highlights the possible cellular and molecular mechanism of anti-nutritional effects of SBA.This review has important implications for the prevention and treatment of SBA-induced diseases,drug development,processing techniques of plant products,prevention of food-borne toxins,as well as human and animal health protection.

Tolerance of Broiler to Dietary Soybean Antinutritional Factors

Raw,heat treated soybean meal and diets made from soybeans extruded at varying temperature were compared to examine dietary threshold levels of the major soybean antinutritional factors(ANF)for broilers.Whole full fat soybeans were extruded at 90,100,110,120,130,or 140 ℃.An in vivo nutritional evaluation of the extruded soybean meals was carried out using 224 Arbor Acres broilers allotted to seven treatments with four replicates of eight birds per pen.As extrusion cooking temperature increased,the urease activity,TI activity,lectin content and PDI decreased.Extruding at 120 ℃ reduced the urease actvity to 0 11 units,the TI activity to 7 20 mg·g -1 ,and lectin content to zero.Raw soybean meal significantly depressed the growth rate of broiler chickens.Remaining ANF obviously reduced feed intake and dietary nitrogen metabolism.The performance of broilers was improved as extrusion temperature increased.Extruding at 110 ℃ produced an effect equal to that of conventional soybean meal.The weight of the pancreas of the birds fed the raw soybean or 90℃ extruded soybean were significantly higher than those in heated soybean meal group and in the higher temperature extruded soyean groups.The same tendency was found from 3 to 7 wk of age.The weights of duodenum and ileum of the broilers fed the raw soybean were significantly higher than those in heated soybean meal group.Extending the feeding of raw soybean or low temperature extruded soybean to 7 wk old broilers significantly increased the fresh weights of proventriculus,jejunum and ileum and dry weights of jejunum and ileum.The villi of birds fed raw soybean meal and low temperature extruded soybean meals were shor tened and damaged.Broilers grew well on the diets containing soybean trypsin inhitory activity as high as 3 74 mg·g -1 without showing any negative effect on the weights of organs and alimentary tracts.

The soybean PLATZ transcription factor GmPLATZ17 suppresses drought tolerance by interfering with stress-associated gene regulation of GmDREB5

Plant AT-rich sequence and zinc binding(PLATZ)transcription factors are a class of plant specific zincdependent DNA-binding proteins that function in abiotic stress response and plant development.In this study,31 GmPLATZ genes were identified in soybean.GmPLATZ17 was down-regulated by drought and exogenous abscisic acid.Transgenic Arabidopsis and soybean hairy roots overexpressing GmPLATZ17 showed drought sensitivity and inhibition of stress-associated gene transcription.In contrast,suppressed expression of GmPLATZ17 led to increased drought tolerance in transgenic soybean hairy roots.The GmPLATZ17 protein was verified to interact physically with the GmDREB5 transcription factor,and overexpression of GmDREB5 increased drought tolerance in soybean hairy roots.Interaction of GmPLATZ17 with GmDREB5 was shown to interfere with the DRE-binding activity of GmDREB5,suppressing downstream stress-associated gene expression.These results show that GmPLATZ17 inhibits drought tolerance by interacting with GmDREB5.This study sheds light on PLATZ transcription factors and the function of GmPLATZ17 in regulating drought sensitivity.

Expression of estrogen receptor alpha,nerve growth factor,interleukin-2,and androgen receptor in the cerebellum of ovariectomized rats following soybean isoflavone treatment

BACKGROUND： Studies have shown that estrogen receptor alpha （ERα）, nerve growth factor （NGF）, interleukin-2 （IL-2）, and androgen receptor （AR） expression in the cerebellum decreases when estrogen levels decrease in vivo. Soybean isoflavone, a type of non-steroid estrogen with similar molecular structure and function to estradiol, exhibits estrogen-like characteristics. OBJECTIVE： To investigate the effects of various doses of soybean isoflavone on expression of ERa, NGF, IL-2, and AR in the cerebellum of ovariectomized rat, and to determine whether there is a dose-dependent effect.DESIGN, TIME AND SETTING： Controlled trial at the cellular and molecular level. The study was performed at the Experimental Animal Engineering Center, College of Veterinary Medicine, Sichuan Agricultural University from July 2006 to May 2008. MATERIALS： Soybean isoflavone, comprised of daidzin, genistein and isoflavone, was provided by Taiyuan Yuantai Biochemical Industry, China. The ERα, NGF, IL-2, and AR in situ hybridization kit, rabbit anti-rat ERa, NGF, IL-2, and AR monoclonal antibodies, and SABC kit were purchased from Wuhan Boster Biological Technology, China. METHODS： A total of 50 female, Sprague Dawley rats, aged 3 months, were randomly assigned to 5 groups, with 10 animals in each group. With the exception of the sham-operation group （abdominal cavity opening alone）, all rats underwent bilateral ovariectomy. At 14 days after surgery, rats in the high-, middle-, and low-dose soybean isoflavone groups were subcutaneously injected with 1.5, 1.0, and 0.5 mg/kg soybean isoflavone, respectively, every 2 days for 6 consecutive weeks. Rats in the sham-operation and ovariectomized groups were subcutaneously injected with absolute alcohol （0.5 mL/kg）. MAIN OUTCOME MEASURES： Expression levels and distribution of ERα, NGF, IL-2, and AR in the cerebellum were detected by immunohistochemistry and in situ hybridization. RESULTS： Compared with the sham-operation group, immunoreactive products and hybridization signals of ERa, NGF, IL-2, and AR were significantly decreased in the cerebellar cortex and nuclei of ovariectomized rats （P 〈 0.05 or P 〈 0.01）, but increased following soybean isoflavone treatment. In particular, levels of the high-dose soybean isoflavone group were almost restored to levels of the sham-operation group （P 〉 0.05）. The immunoreactive products were primarily located in the cytoplasm and neurites, and rarely in the cell membrane and nuclei. However, the hybridization signals were predominantly located in the nuclei, but rarely in the cytoplasm, cell membrane, or neurites. CONCLUSION： Soybean isoflavone upregulated ERα, NGF, IL-2, and AR protein and gene expression in a dose-dependent manner, and played an important role in sustaining and protecting structure and function of cerebellar neurons. Moreover, the similarity of expression patterns of these molecules indicated that they were mutually interactive during the regulation of soybean isoflavone to the cerebellum.

Assessing Total Factor Productivity for Soybean Production in China Based on DEA-Malmquist Index: 2005-2017

The low and slowly increasing soybean yield restricts the development of soybean production. Accurate measures of total factor productivity (TFP) for soybean production can be helpful in identifying conditions, institutions or policies that promote soybean production development in China. In this paper, TFP growth for soybean production was estimated for a panel data of 10 major soybean producing provinces from 2005 to 2017. Results reveal that TFP grew at an average rate of 1.3% over the whole period, with technical progress contributing 2.3% and efficiency change providing the other -1.0%. The change of TFP for soybean production over that time, whether increase or decline, was mainly derived by technical change except in three years (2005-2007). Positive TFP growth in the provinces of Liaoning and Inner Mongolia, and negative TFP growth in Hebei and Anhui were mainly driven by efficiency change, specifically scale efficiency change except pure technical efficiency in Liaoning.

Factors That Compromise the Nutritional Value of Cowpea Fluor and Its Protein Isolates

Anti-nutritional studies on cowpea (Vigna ungiculata L.) seeds as whole cowpea flour (WCF), dehulled cowpea flour (DCF), dehulled defatted cowpea flour (DDCF) and protein isolates obtained from DDCF by isoelectric (CPIA) and micellization (CPIB) precipitation. The protein content of WCF and DDCF were 22.3% and 26.75% respectively, while CPIA and CPIB showed 75% and 76% respectively. The abundant minerals in WCF and DCF were calcium (32.38 - 33.61 mg/100 g);potassium (29.25 - 24.99 mg/100 g);and sodium (1.76 - 1.00 mg/100 g). The least abundant minerals were iron (0.004 - 0.013 mg/100 g);copper (0.04 - 0.25 mg/100 g);manganese (0.18 - 0.30 mg/100 g) and zinc (0.26 - 1.22 mg/100 g);respectively. Trypsin inhibitor activity for WCF, CPIA and CPIB was found 16,640 TIU/g, 4293 TIU/g and 4290 TIU/g respectively. Condensed tannins in RCF and DDCF were found 0.003% and 0.004% respectively while phytic acid content 0.8% and 1.17% respectively, no phytic acid and tannins were observed in protein isolates. Cowpea flour was also similar to other edible grain legumes in content of anti-nutritional factors;appropriate processing methods improved cowpea nutritive value and significantly reduced the levels of anti-nutritional factors.

Effects of Different Grinding Methods on the Quality of Soybean Bean Milk

[Objectives] This study was conducted to improve the nutritional value of soybean milk, enrich the variety and taste of soybean milk, and find healthy food that is more conducive to people s nutritional needs. [Methods] Whole soybean milk was prepared by grinding with a grinding wheel at a low concentration (low-concentration grinding) and a stainless steel mill at a high concentration (high-concentration grinding). The sensory, physical and chemical characteristics and anti-nutritional factors of whole soybean milk produced by different grinding methods were studied. [Results] Compared with low-concentration grinding, the protein content in soybean milk prepared by high-concentration grinding increased by 24%, and the dietary fiber content increased by 74.7%. Before and after high-pressure homogenization, the particle size D(4, 3) of soybean milk prepared by low-concentration grinding was 212.1 and 93.59 μm, respectively, and the particle size D(4, 3) of soybean milk prepared by high-concentration grinding was 134.0 and 64.64 μm, respectively. The trypsin inhibitor activity and phytic acid content of soybean milk prepared by high-concentration grinding were significantly lower than those of soybean milk prepared by low-concentration grinding. [Conclusions] This study improves the diet structure of the broad masses of people, strengthens people s physique, and provides a new idea for the implementation and development of China s "Soybean Action Programme".

Soybean GmMYB76, GmMYB92, and GmMYB177 genes confer stress tolerance in transgenic Arabidopsis plants

MYB-type transcription factors contain the conserved MYB DNA-binding domain of approximately 50 amino acids and are involved in the regulation of many aspects of plant growth, development, metabolism and stress responses. From soybean plants, we identified 156 GmMYB genes using our previously obtained 206 MYB unigenes, and 48 were found to have full-length open-reading frames. Expressions of all these identified genes were examined, and we found that expressions of 43 genes were changed upon treatment with ABA, salt, drought and/or cold stress. Three GmMYB genes, GmMYB76, GmMYB92 and GmMYB177, were chosen for further analysis. Using the yeast assay system, GmMYB76 and GmMYB92 were found to have transactivation activity and can form homodimers. GmMYB177 did not appear to have transactivation activity but can form heterodimers with GmMYB76. Yeast onehybrid assay revealed that all the three GmMYBs could bind to cis-elements TAT AAC GGT TTT TT and CCG GAA AAA AGG AT, but with different affinity, and GmMYB92 could also bind to TCT CAC CTA CC. The transgenic Arabidopsis plants overexpressing GmMYB 76 or GmMYB177 showed better performance than the GmMYB92-transgenic plants in salt and freezing tolerance. However, these transgenic plants exhibited reduced sensitivity to ABA treatment at germination stage in comparison with the wild-type plants. The three GmMYB genes differentially affected a subset of stress-responsive genes in addition to their regulation of a common subset of stress-responsive genes. These resuits indicate that the three GmMYB genes may play differential roles in stress tolerance, possibly through regulation of stress-responsive genes.

GmPHR1, a Novel Homolog of the AtPHR1 Transcription Factor, Plays a Role in Plant Tolerance to Phosphate Starvation

GmPHR1 from soybean （Glycine max） was isolated and characterized. This novel homolog of the AtPHR1 transcription factor confers tolerance to inorganic phosphate （Pi）-starvation. The gene is 2 751 bp long, with an 819-bp open reading frame and ifve introns. Analysis of transcription activity in yeast revealed that the full-length GmPHR1 and its C-terminal activate the reporter genes for His, Ade and Ura, suggesting that the C-terminal peptide functions as a transcriptional activator. Quantitative real-time PCR indicated that patterns of GmPHR1 expression differed. For example, under low-Pi stress, this gene was quickly induced in the tolerant JD11 after 0.5 h, with expression then decreasing slowly before peaking at 12-24 h. By contrast, induction in the sensitive Niumaohuang （NMH） was slow, peaking at 6 h before decreasing quickly at 9 h. GmPHR1 showed sub-cellular localization in the nuclei of onion epidermal cells and Arabidopsis roots. Growth parameters in wild-type （WT） Arabidopsis plants as well as in overexpression （OE） transgenic lines were examined. Under low-Pi conditions, values for shoot, root and whole-plant dry weights, root to shoot ratios, and lengths of primary roots were signiifcantly greater in OE lines than in the WT. These data demonstrate that GmPHR1 has an important role in conferring tolerance to phosphate starvation.

Biological and Economic Efficiency of Partial Dietary Substitution of Soybean (Glycine max) Meal with Cowpea (Vigna unguiculata) Meal in Broiler Production

This manuscript explores the biological and economic efficiency of partial dietary substitution of soybean (Glycine max) meal with cowpea (Vigna unguiculata) meal in broiler production. As a result of the shortage of soybean in Zimbabwe due to droughts, inadequate irrigation infrastructure, high input costs, and price controls, the authors identified an alternative to soybean meal in cowpea meal due to its availability and similar amino acid profile to soybean meal. The experiment was carried out at Cold Storage Company in Kadoma. A total of 150 unsexed day-old broiler chicks (Cobb 500) were used. All the birds were brooded in one pen during the first two weeks of age and fed with standard broiler starter mash from National Foods PVT LTD for adaptation. The birds were randomly allocated into five equal groups, each with three replicates and 10 birds per replicate at three weeks of age. Five experimental diets: T1 (100% soybean meal + 0% cowpeas meal), T2 (75% soybean meal + 25% cowpeas meal), T3 (50% soybean meal + 50% cowpeas meal), T4 (25% soybean meal + 75% cowpeas meal) and T5 (0% soybean meal + 100% cowpeas meal) were formulated to be iso-caloric and iso-nitrogenous to meet nutrient requirements of broilers according to NRC (2001). Ration formulation using maize, soybean and cowpea meal as ingredients for broiler starter (21% Crude Protein) and broiler finisher (19% Crude Protein) was done using the Pearson Square Method. Feed intake (g) and weight gain (g) were recorded weekly. Feed Conversion Ratio (FCR) and bioeconomic efficiency were calculated weekly. The experiment lasted for five weeks. The results showed that total Dry Matter Intake for Treatment 1 was the highest (3285 g), and Dry Matter Intakes for Treatments 2, 3 and 4 (3284 g, 3284 g and 3284 g) were not significantly different (P > 0.05) and Dry Matter Intake for Treatment 5 was the lowest (3282 g). Weight gains for Treatments 1 and 2 (2089 g and 2089 g) were not different (P > 0.05), Treatments 3 and 4 (2098 g and 2103 g) were not different (P > 0.05) and Treatment 5 had the lowest gain of 1990 g. Feed Conversion Ratio for Treatments 1 and 2 (1.572 and 1.572) was not significantly different (P > 0.05), Treatments 3 and 4 (1.565 and 1.562) were not different (P > 0.05) and Treatment 5 had the highest FCR (1.64). The bioeconomic efficiency results were significantly different (P < 0.05) for Treatments 1, 2, 3, 4 and 5 (42.16, 41.93, 41.46, 41.13 and 42.66, respectively). Based on the analyses and results, the authors concluded that cowpea meal prepared from boiled cowpea grain can be used to replace soybean meal in broiler diets at 50% and 75% inclusion, respectively. This study is unique and interesting and suitable for acceptance in this journal because it seeks to provide an alternative to feeds for the ever-growing broiler industry in Zimbabwe and the rest of the world.

Biological and Economic Efficiency of Partial Dietary Substitution of Soybean (Glycine max) Meal with Cowpea (Vigna unguiculata) Meal in Broiler Production

This manuscript explores the biological and economic efficiency of partial dietary substitution of soybean (Glycine max) meal with cowpea (Vigna unguiculata) meal in broiler production. As a result of the shortage of soybean in Zimbabwe due to droughts, inadequate irrigation infrastructure, high input costs, and price controls, the authors identified an alternative to soybean meal in cowpea meal due to its availability and similar amino acid profile to soybean meal. The experiment was carried out at Cold Storage Company in Kadoma. A total of 150 unsexed day-old broiler chicks (Cobb 500) were used. All the birds were brooded in one pen during the first two weeks of age and fed with standard broiler starter mash from National Foods PVT LTD for adaptation. The birds were randomly allocated into five equal groups, each with three replicates and 10 birds per replicate at three weeks of age. Five experimental diets: T1 (100% soybean meal + 0% cowpeas meal), T2 (75% soybean meal + 25% cowpeas meal), T3 (50% soybean meal + 50% cowpeas meal), T4 (25% soybean meal + 75% cowpeas meal) and T5 (0% soybean meal + 100% cowpeas meal) were formulated to be iso-caloric and iso-nitrogenous to meet nutrient requirements of broilers according to NRC (2001). Ration formulation using maize, soybean and cowpea meal as ingredients for broiler starter (21% Crude Protein) and broiler finisher (19% Crude Protein) was done using the Pearson Square Method. Feed intake (g) and weight gain (g) were recorded weekly. Feed Conversion Ratio (FCR) and bioeconomic efficiency were calculated weekly. The experiment lasted for five weeks. The results showed that total Dry Matter Intake for Treatment 1 was the highest (3285 g), and Dry Matter Intakes for Treatments 2, 3 and 4 (3284 g, 3284 g and 3284 g) were not significantly different (P > 0.05) and Dry Matter Intake for Treatment 5 was the lowest (3282 g). Weight gains for Treatments 1 and 2 (2089 g and 2089 g) were not different (P > 0.05), Treatments 3 and 4 (2098 g and 2103 g) were not different (P > 0.05) and Treatment 5 had the lowest gain of 1990 g. Feed Conversion Ratio for Treatments 1 and 2 (1.572 and 1.572) was not significantly different (P > 0.05), Treatments 3 and 4 (1.565 and 1.562) were not different (P > 0.05) and Treatment 5 had the highest FCR (1.64). The bioeconomic efficiency results were significantly different (P < 0.05) for Treatments 1, 2, 3, 4 and 5 (42.16, 41.93, 41.46, 41.13 and 42.66, respectively). Based on the analyses and results, the authors concluded that cowpea meal prepared from boiled cowpea grain can be used to replace soybean meal in broiler diets at 50% and 75% inclusion, respectively. This study is unique and interesting and suitable for acceptance in this journal because it seeks to provide an alternative to feeds for the ever-growing broiler industry in Zimbabwe and the rest of the world.

四川省大豆生产格局变化及驱动因素研究

四川省是我国13个粮食主产区之一,也是我国大豆种植的新兴地区和西南产区的重要组成,研究大豆生产格局对四川省落实粮食安全战略、推动西南地区大豆产业发展具有重大意义。文章基于2000—2020年四川省183个区市县的面板数据,运用空间基尼指数、地理集中度系数、空间转移系数、探索性空间数据分析、最优地理探测器分析了大豆生产的时空格局变化及驱动因素。研究结果发现:1)2000—2020年,四川省大豆产能波动上升,空间分布极不均衡,聚集水平逐步上升,并逐步向川中丘陵区集中;2)大豆生产存在较强的正向空间相关性,总体表现为高-高聚集和低-低聚集;3)资源要素、比较收益、地理气候、经济社会等因素对大豆生产格局变化的影响均高度显著,且呈现非线性增强、双因子增强的交互效应。资源要素投入、比较收益、海拔高程长期以来对大豆生产格局的影响较为显著且呈波动上升趋势,气温、乡村家庭规模的影响力提升较快,交通条件、地区GDP的影响力则总体呈下降趋势,耕作制度长期以来驱动力最弱。基于此,四川省大豆生产应着力破解耕地资源细碎化与劳动力短缺等资源环境约束,大力发展生产性服务业,全面提升大豆生产机械化水平。通过强化科技创新提升川豆单产,并进一步优化大豆生产、农机、服务、保险等环节的政策保障。同时,应重点关注气候变化引发的干旱等自然风险,健全农业领域自然灾害风险预警与防范机制,以进一步强化大豆产业的综合风险抵御能力。

抗氧化途径下大豆GmbHLH130转录因子增强植物耐旱性研究

为了探究大豆GmbHLH130基因参与植物耐旱性调控的分子机制,分析了转基因拟南芥在干旱处理下的表型并测定活性氧含量和抗氧化酶活性,同时检测了拟南芥叶中干旱应答相关基因的表达模式以及转录因子GmbHLH130对下游基因启动子的结合作用。结果显示,GmbHLH130基因过表达拟南芥的耐旱性明显增强。干旱处理下,过表达株系鲜质量和叶片相对含水量均高于WT,而MDA含量和失水率则较低。此外,干旱处理导致拟南芥过表达株系积累更多的可溶性糖和脯氨酸、更少的活性氧以及更高的抗氧化酶活性;同时,干旱胁迫应答基因AtCAT、AtPOD、AtSOD、AtNCED3、AtP5CS1和AtRD29A的表达水平在过表达株系中显著上调。GmbHLH130蛋白则可结合到靶基因的启动子区激活GUS报告基因的表达。本研究初步证明GmbHLH130转录因子通过结合干旱胁迫应答基因启动子激活基因表达,增加转基因植株体内渗透调节物质含量、激活抗氧化途径和提高ROS清除能力,最终缓解干旱胁迫对植株的损伤。

南方土壤中导致大豆皱叶的因子分析

为找出南方大豆皱叶症发生的诱因,本研究从南方土壤中非生物因素和生物因素两个角度进行探索研究。利用混池法和ICP-OES技术研究正常叶混池和皱叶混池的差异元素,利用构建的皱叶残留异质系中皱叶家系材料GY_C和正常叶家系材料GY_N,采用单因素随机区组试验设计,研究皱叶土壤的不同土层、营养液、灰烬、叶浆,进行土壤浸泡液、土壤消毒、氮肥等处理后大豆皱叶材料皱叶症的变化。结果表明:皱叶环境土壤的表层、中层和底层土均可导致GY_C叶片皱缩,中层土中的GY_C叶片皱缩程度略高于表层和底层土。氮磷钾配比失衡的营养液处理GY_C叶片未发生皱缩。ICP-OES分析皱叶混池E 1和正常叶混池E 0的31种元素后,未发现E 1/E 0比值为1.7倍以上的元素,且E 1中锰元素含量低于E 0。皱叶灰烬及土壤浸泡液处理基质后GY_C叶片未发生皱缩。移栽试验表明,南方土壤和基质比例超过3∶1时GY_C长出的新叶依然皱缩,而复种的盆栽中南方土壤和基质比例低于1∶8时GY_C叶片也会发生皱缩,且随着复种次数增加,皱叶程度有所增加。解剖观察皱叶材料的根、茎、叶柄未发现明显的虫害痕迹。-80,60,80,100和120℃处理的南方土壤中GY_C叶片不发生皱缩。综上所述,南方土壤中的微生物因素可能是导致大豆皱叶的关键因子。

基于大豆叶枕响应叶柄角变化转录组的MYB基因分析

【目的】阐明MYB基因家族成员是否参与大豆叶柄角(leaf petioles angle,LPA)变化的调控过程,为大豆理想株型育种研究奠定基础。【方法】以郑196为材料,利用大豆叶枕响应叶片向光运动转录组挖掘差异表达大豆MYB基因(GmMYB);利用ProtComp 9.0进行亚细胞定位预测;以拟南芥MYB蛋白序列为参考,采用MEGA v5.0软件进行系统进化分析;分别利用在线程序MEME和PlantPAN3.0分析差异表达MYB基因保守基序(motif)和启动子序列的顺式作用元件;以NCBI数据库中大豆转录组数据及RNA-seq数据为基础,采用TBtools进行表达模式分析,并在此基础上进行候选基因的精准定量检测。【结果】①鉴定出13个差异表达GmMYB,其中上调表达9个,下调表达4个;亚细胞定位结果表明,11个MYB蛋白位于细胞核,2个位于细胞外基质。②基于MYB蛋白序列构建系统进化树,可将13个差异表达GmMYB分为6组。③对13个差异表达GmMYB基因结构进行分析,结果共鉴定到10个基序,其中基序1和基序2是MYB保守结构域的一部分。④在启动子区域鉴定获得脱落酸响应元件、参与干旱响应元件、响应光照的顺式作用元件、分生组织表达和生长素响应等多个响应逆境胁迫及光照的顺式作用元件。⑤表达模式分析结果表明,13个差异表达GmMYB基因在大豆不同组织器官中存在表达差异,其中Glyma.01G190100和Glyma.08G042100在叶枕处表达。⑥对Glyma.01G190100和Glyma.08G042100进行精准定量检测,结果显示其相对表达量在叶片向光运动前后变化剧烈,可作为大豆叶柄角调控候选基因用于进一步研究。【结论】鉴定出13个与大豆叶柄角调控相关的MYB基因,其中Glyma.01G190100和Glyma.08G042100可作为大豆叶柄角调控候选基因用于大豆理想株型育种研究。