Genome-wide association mapping and genomic prediction of stalk rot in two mid-altitude tropical maize populations

Maize stalk rot reduces grain yield and quality.Information about the genetics of resistance to maize stalk rot could help breeders design effective breeding strategies for the trait.Genomic prediction may be a more effective breeding strategy for stalk-rot resistance than marker-assisted selection.We performed a genome-wide association study(GWAS)and genomic prediction of resistance in testcross hybrids of 677 inbred lines from the Tuxpe?o and non-Tuxpe?o heterotic pools grown in three environments and genotyped with 200,681 single-nucleotide polymorphisms(SNPs).Eighteen SNPs associated with stalk rot shared genomic regions with gene families previously associated with plant biotic and abiotic responses.More favorable SNP haplotypes traced to tropical than to temperate progenitors of the inbred lines.Incorporating genotype-by-environment(G×E)interaction increased genomic prediction accuracy.

Pulsatile gonadotropin-releasing hormone therapy induces spermatogenesis in pituitary stalk interruption syndrome:A case report and review of the literature

BACKGROUND Pituitary stalk interruption syndrome(PSIS)is a rare anatomical defect of the pituitary gland falling under the spectrum of holoprosencephaly phenotypes.It is characterized by a deficiency in anterior pituitary hormones,such as growth hormone,gonadotropins,and thyroid hormones.Due to the syndrome's rarity and nonspecific manifestations,there is a lack of standardized treatment strategies.Consequently,early diagnosis through imaging and on-time intervention are crucial for improving patients’outcomes.CASE SUMMARY A 30-year-old man presented with absent secondary sexual characteristics and azoospermia.Laboratory evaluation revealed a deficiency in gonadotropins,while thyroid function was mostly within normal ranges.Magnetic resonance imaging of the pituitary gland showed pituitary stalk agenesis,hypoplasia of the anterior pituitary,and ectopic posterior pituitary,leading to the diagnosis of PSIS.Initially,the patient underwent 6 mo of gonadotropin therapy without significant changes in hormone levels and secondary sexual characteristics.Pulsatile gonadotropin-releasing hormone therapy was then administered,resulting in the detection of sperm in the semen analysis within 3 mo.After 6 mo,routine semen tests showed normal semen quality.The couple faced challenges in conceiving due to abstinence and underwent three cycles of artificial insemination,which was unsuccessful.They also attempted in vitro fertilization,but unfortunately,the woman experienced a miscarriage 10 wk after the embryo transfer.CONCLUSION Early detection,accurate diagnosis,and timely treatment are crucial in improving the quality of life and fertility of PSIS patients.

Pituitary stalk interruption syndrome complicated with liver cirrhosis:A case report

BACKGROUND Pituitary stalk interruption syndrome(PSIS)is a rare disorder,often characterized by delayed growth and development,short stature,and hypogonadism as the main clinical manifestations.It is not clear whether PSIS can lead to liver cirrhosis.CASE SUMMARY This paper reported a case of liver cirrhosis of unknown origin.The patient was admitted to Beijing Ditan Hospital Affiliated to Capital Medical University in November 2023.The diagnosis of PSIS complicated with liver cirrhosis was established after a series of blood tests and pituitary magnetic resonance imaging examination.CONCLUSION We also reviewed the literature from both domestic and international sources to deepen the clinical understanding of PSIS in conjunction with liver cirrhosis among medical practitioners.

Dissecting the genetic architecture of glucosinolate compounds for quality improvement in flowering stalk tissues of Brassica napus

Glucosinolates(GSLs) and their hydrolytic products contribute to the quality traits of rapeseed flowering stalk tissues, such as taste, flavor and anticarcinogenic properties(Glucoraphanin). However, little is known about the genetic mechanisms of GSL accumulation in rapeseed flowering stalks. In this study, the variation and genetic architecture of GSL metabolites in flowering stalk tissues were investigated for the first time among a panel of 107 accessions. All GSL compounds exhibited continuous and wide variations in the present population. Progoitrin,glucobrassicanapin and gluconapin were the most abundant GSL compounds. Five quantitative trait loci(QTL) significantly associated with three GSL compounds were identified by genome-wide association study. GRA_C04 was under selected during modern breeding, in which the ratio of lower GSL haplotype(HAP2) in the accessions bred before 1990(52.56%) was significantly lower than that after 1990(78.95%). Four candidate genes, BnaA01. SOT16, BnaA06. SOT17, Bna A06. MYB51a, and Bna A06. MYB51b, were identified in the GTL_A01 and 4OH_A06 regions.These findings provide new insights into GSL biosynthesis in flowering stalk tissues and facilitate quality improvement in rapeseed flowering stalks.

Genome-wide association study identifies novel candidate loci or genes affecting stalk strength in maize

Stalk strength increases resistance to stalk lodging,which causes maize(Zea mays L.)production losses worldwide.The genetic mechanisms regulating stalk strength remain unclear.In this study,three stalk strength-related traits(rind penetrometer resistance,stalk crushing strength,and stalk bending strength)and four plant architecture traits(plant height,ear height,stem diameter,stem length)were measured in three field trials.Substantial phenotypic variation was detected for these traits.A genome-wide association study(GWAS)was conducted using general and mixed linear models and 372,331 single-nucleotide polymorphisms(SNPs).A total of 94 quantitative trait loci including 241 SNPs were detected.By combining the GWAS data with public gene expression data,56 candidate genes within 50 kb of the significant SNPs were identified,including genes encoding flavonol synthase(GRMZM2G069298,ZmFLS2),nitrate reductase(GRMZM5G878558,ZmNR2),glucose-1-phosphate adenylyltransferase(GRMZM2G027955),and laccase(GRMZM2G447271).Resequencing GRMZM2G069298 and GRMZM5G878558 in all tested lines revealed respectively 47 and 2 variants associated with RPR.Comparison of the RPR of the zmnr2EMS mutant and the wild-type plant under high-and low-nitrogen conditions verified the GRMZM5G878558 function.These findings may be useful for clarifying the genetic basis of stalk strength.The identified candidate genes and variants may be useful for the genetic improvement of maize lodging resistance.

Improvement of Methane Production from Corn Stalk for Whole Slurry Anaerobic Co-digestion Under Hydrothermal Wastewater Pretreatment

Corn stalk hydrothermal wastewater(CSHW)was used as a pretreatment for whole-slurry anaerobic co-digestion instead of conventional acid pretreatment.CSHW pretreatment was conducted at 20℃,35℃and 50℃for 3,6 and 9 h,after which all experimental groups were digested at 35℃for 24 days.This pretreatment method efficiently broke the lignocellulose structure of the corn stalk.Different from the volatile fatty acids(VFAs)content,the pH and RS contents were relatively higher than those of the control during the pretreatment process.Furthermore,the highest methane production[185.03 mL•g-1 VS(volatile solid)]was achieved at 55.46%under 35℃in 6 h,which was higher than that of the normal corn stalk anaerobic digestion.The VFAs contents and pH increased compared to CK upon the addition of NaOH to adjust pH,and the RS content also increased slightly due to the degradability of lignocellulose during the whole-slurry anaerobic co-digestion.This work provided a potential method to sustainably treat wastewater and improve fermentation performance.

MUTS-Based Cooperative Target Stalking for A Multi-USV System

This paper is concerned with the cooperative target stalking for a multi-unmanned surface vehicle(multi-USV)system.Based on the multi-agent deep deterministic policy gradient(MADDPG)algorithm,a multi-USV target stalking(MUTS)algorithm is proposed.Firstly,a V-type probabilistic data extraction method is proposed for the first time to overcome shortcomings of the MADDPG algorithm.The advantages of the proposed method are twofold:1)it can reduce the amount of data and shorten training time;2)it can filter out more important data in the experience buffer for training.Secondly,in order to avoid the collisions of USVs during the stalking process,an action constraint method called Safe DDPG is introduced.Finally,the MUTS algorithm and some existing algorithms are compared in cooperative target stalking scenarios.In order to demonstrate the effectiveness of the proposed MUTS algorithm in stalking tasks,mission operating scenarios and reward functions are well designed in this paper.The proposed MUTS algorithm can help the multi-USV system avoid internal collisions during the mission execution.Moreover,compared with some existing algorithms,the newly proposed one can provide a higher convergence speed and a narrower convergence domain.

辽宁省玉米秸秆基质栽培糙皮侧耳菌株筛选评价

为筛选出适宜辽宁地区以玉米秸秆为主要栽培基质的优良糙皮侧耳菌株,以19个糙皮侧耳菌株为试验材料,对菌丝长势、满袋时间、污染率、生物学效率及农艺性状等指标进行测定和比较分析。结果表明,C14号菌株综合指标优于其他供试菌株,其母种和栽培种在玉米秸秆基质中菌丝长势均较好,生物学效率较高,为105.8%,子实体菌盖颜色深灰色,菌柄3.1~6.8 cm,朵大韧性好,菇型紧凑,菌盖肥厚,中等大小,光泽好,可作为生产用优良菌株。C10、C2号菌株子实体性状一般,但其母种及栽培种在玉米秸秆基质中菌丝长势强、生物学效率高,利用秸秆能力强,可作为品种选育的备选材料。

棉秆和油页岩共热解生物炭的氨氮吸附性能研究

使用棉秆(CS)和油页岩(OS)为原料,采用共热解的方式制备了共热解生物炭,探究了对氨氮的吸附性能。考察了不同热解时间、CS和OS比例、热解温度、CS的粒径对共热解生物炭的氨氮吸附量的影响规律,确定了最佳制备条件,并研究了吸附动力学和吸附等温线模型。研究表明,棉秆和油页岩共热解后生物炭的结构特性和表面形貌有较大改善,对氨氮的吸附能力有明显的提高。最佳的制备条件是热解温度为500℃、m(棉秆)∶m(油页岩)=3∶1、热解时间为30 min和CS的粒径为0.20~0.30 mm。在投加量为10.0 g/L、pH 9.0时,最佳条件所制备炭的吸附量为4.89 mg/g,是棉秆生物炭的2.2倍。吸附过程以准二级动力学和Langmuir等温吸附模型描述。吸附机制主要包括为离子交换、静电吸附和配位作用。

玉米秸秆堆腐还田对黑土区土壤性状的影响

本研究针对东北地区秋冬季节气候寒冷特点和秸秆堆腐还田的实际操作需求,开展秸秆堆腐还田试验。在秋季玉米收获之后进行田间堆腐试验,期间连续监测环境温度、降水、秸秆堆温度、秸秆失重率等指标。离田玉米秸秆经过腐熟后作为肥料还田,连续施用3年,检测土壤有机质、碱解氮、速效磷、速效钾、土壤孔隙度、土壤容重等指标。在基本农田和棚室保护地进行为期2年的应用试验。结果表明:120 d秸秆失重率达到31.53%。施用腐熟秸秆3年,土壤有机质提高了4.06~6.31 g/kg、土壤中碱解氮提高了15.08~27.35 mg/kg、速效磷提高了18.11~21.95 mg/kg、速效钾提高63.97~89.93 mg/kg;土壤容重降低了0.10~0.14 g/cm^(3)、土壤田间持水量提高了7.51%~9.24%(V/V)、土壤孔隙度提高了3.69%~5.27%(V/V),且差异显著(P≤0.05)。基本农田和棚室保护地应用试验中,速效养分与有机质有所增长,土壤容重与田间持水量变化显著。逐年施用腐熟秸秆对于提高土壤有机质含量、速效养分具有显著作用。同时,施用腐熟秸秆能够降低土壤容重,提高土壤孔隙度与田间持水量,改善土壤板结问题。腐熟秸秆在改良与保育黑土性质方面具有良好的作用。

玉米秸秆刨花板压制工艺优化及吸水厚度膨胀率

农作物秸秆用作人造板原材料,可减少环境污染,缓解木材供需紧张,秸秆中纤维素与木质素含量可以满足人造板生产要求。以玉米秸秆刨花为原料,在一定热压压力、热压时间、刨花密度、热压温度下,采用不同施胶量无机胶黏剂压制玉米秸秆刨花板,探索最优工艺参数及玉米秸秆刨花板吸水厚度膨胀率变化规律。结果显示:压制玉米秸秆刨花板的最优工艺参数为刨花含水率12%、热压压力1.6MPa、热压时间9min、刨花密度1.0g/cm^(3)、施胶量20%、热压温度90℃;影响玉米秸秆刨花板吸水厚度膨胀率的因素依次为刨花含水率>热压压力>热压时间>刨花密度>施胶量>热压温度。试验结果表明:在吸水厚度膨胀率合格的前提下,玉米秸秆刨花板的内结合强度、弹性模量、静曲强度均符合国家标准规定的性能要求。

Using Sorghum Stalk as a Partial Replacement of Lime in the Stabilization of Red Clay Soil for Road Sub-Grade Construction

This research aimed at testing the viability of using Sorghum Stalk Ash (SSA) as a partial replacement of lime in the stabilization of red clay soils for road subgrade construction. Red clay soils have been identified as highly expansive soils, which are affected by both climatic conditions and loading patterns. The consideration of both traffic loading patterns and climatic effects on these soils has been taken into account. A penetration test of 2.5 mm has been used on both pure red soils and stabilized soils at 10% and 15% partial replacement of lime with SSA and showed an improvement in the CBR of stabilized red clay soils up to 11.6%. Again, the PI of stabilized soils at 15% partial replacement of lime reduced up to 11.2%. The results obtained on both CBR and PI of these red clay soils are within the recommended values for the effective subgrade required for laying both permanent and flexible pavements. As a result, a recommendation of making use of SSA to lower the quantities of lime and its costs used in the stabilization of highly expansive soils have been tested through this research. However, further research on a more percentage partial replacement of lime to improve the PI of these soils to below 10% while keeping the CBR levels within the road construction regulations is welcomed.

丘陵山地不同种植模式下甘蔗主栽品种生产的潜力

【目的】以丘陵山地不同种植模式甘蔗主栽品种生产潜力为研究对象,探索品种和机械适应关系,筛选宜机化(适宜机械作业)种植的甘蔗品种并明确其主要特征,为推动丘陵山地蔗区全程机械化提供理论支撑。【方法】选择云南丘陵山地2种不同生态类型蔗区,对桂柳05-136、云蔗05-49、云蔗05-51和云蔗08-1609 4个主栽品种进行全程机械化和全程人工2种种植模式下生产潜力研究。【结果】甘蔗产量和蔗糖分受品种和种植模式影响,其中产量影响显著,机械化种植模式下,云蔗08-1609产量显著高于人工种植模式(P<0.01),云蔗05-51表现相反(P<0.01);机械化种植模式下,云蔗08-1609蔗糖分略高于人工种植(P>0.05),桂柳05-136和云蔗05-49略降低(P>0.05)。甘蔗下种量和出苗率同时受品种特性和种植模式影响,机械化种植模式下下种量普遍高于人工种植,而出苗率普遍低于人工种植模式;云蔗05-51机械化种植条件下出苗率显著降低(P<0.05),云蔗08-1609出苗率相对较稳定(P>0.05)。甘蔗主要农艺性状同时受品种和种植模式影响,机械化种植模式下,云蔗08-1609有效茎显著高于人工种植模式(P<0.05);工艺品质性状主要受品种影响。云蔗08-1609在甘蔗机械种植条件下生长潜力更高,表现为产量和有效茎显著高于人工种植,甘蔗蔗糖分略高;云蔗05-51在人工种植模式条件下生长潜力更高,表现为人工种植模式下的产量更高。【结论】不同甘蔗品种对机械种植的适应程度不同,存在宜机化种植和宜人工种植甘蔗品种,在推进机械化种植模式过程中应充分考虑品种的适应性;总之,宜机化种植甘蔗品种应具备在机械化种植模式下的甘蔗产量更高和有效茎更多,且蔗糖分受种植模式影响较小甚至略高于人工种植模式的特征。

玉米秸秆中7种游离单糖的高效液相色谱测定方法

本研究旨在建立一种测定玉米秸秆中7种游离单糖[D(+)-葡萄糖、L-鼠李糖、D(+)-木糖、L-阿拉伯糖、D(-)-核糖、D(+)-半乳糖和D(+)-甘露糖]的高效液相色谱测定方法。将玉米秸秆在60℃干燥后粉碎,以水作为提取溶剂,98℃水浴提取1 h,冷却后离心取上清液;利用1-苯基-3-甲基-5-吡唑啉酮(PMP)衍生化处理,上清液过0.22μm滤膜,以Agilent Zorbax SB-C_(18)色谱柱进行高效液相色谱分析,7种组分在56 min内达到分离。结果表明:D(+)-葡萄糖、L-鼠李糖、D(+)-木糖、L-阿拉伯糖、D(-)-核糖、D(+)-半乳糖和D(+)-甘露糖的保留时间和峰面积的日内相对标准偏差均分别小于1.0%和5.0%,日间相对标准偏差均分别小于1.0%和7.5%;线性范围分别为0.31~2 000μg/mL、 0.31~200μg/mL、 0.50~200μg/mL、0.75~200μg/mL、0.31~200μg/mL、0.75~200μg/mL和0.31~200μg/mL,线性关系良好,相关系数均达到0.999以上;检出限为0.10~0.25μg/mL,加标回收率为79.9%~114.8%。由此可见,本研究建立的方法不仅操作简单,还可以对玉米秸秆中的7种游离单糖准确定量,为研究玉米秸秆中糖类物质含量以及在动物体内的消化吸收提供技术支撑。

油菜薹中啶虫脒残留质控样品的制备与评价

为保障油菜薹中啶虫脒农药残留快速检测结果的准确性和可靠性,建立油菜薹中啶虫脒质控样品的制备方法并进行评价。采用基质加标、真空冷冻干燥的方法制备冻干质控样品。采用液相色谱质谱串联的检测方法对质控样品中的啶虫脒含量进行测定,通过随机抽样检验以评估样品的均匀性,通过观察质控样品在一个月内啶虫脒含量变化以评估样品的稳定性。该方法制备的油菜薹中啶虫脒农药残留质控样品均匀性和稳定性良好,便于储存和运输,适用于快检产品验证、盲样考核等快速检测领域。本研究建立了一种流程简单的油菜薹冻干粉质控样品制备方法,为蔬菜中农药残留质控样品制备共性关键技术研究提供了数据参考。

大豆皂脚与玉米秸秆厌氧发酵沼渣共热解特性及应用

将大豆皂脚与玉米秸秆厌氧发酵沼渣两种固体废弃物以不同比例混合后进行共热解,采用元素分析、扫描电子显微镜(SEM)、N_2吸附-脱附法(BET)对得到的共热解炭进行表征,并将共热解炭循环应用到玉米秸秆厌氧发酵环境中,考察共热解炭对厌氧发酵过程的影响。结果表明:共热解炭的产率随着沼渣加入量的增大而增大;沼渣加入量较少时,可以促进共热解气的生成,但对共热解液的产生有较弱的抑制作用;共热解炭的比表面积和平均孔径介于两种单一热解炭之间,并且平均孔径随沼渣加入量的增大呈减小趋势;将大豆皂脚与沼渣的质量比为4∶3下制备的共热解炭加入厌氧发酵系统中,发酵30 d时累积产气量达到390.80 mL/g,累积产甲烷量达到213 mL/g,累积产气量达到总产气量80%所需要的时间t_(80)为(14±1) d,比不添加热解炭的空白组提前了12.5%。

玉米秸秆青贮、玉米秸秆、桑叶青贮三种饲料体外发酵组合效应研究

为了研究玉米秸秆青贮、玉米秸秆与桑叶青贮在体外的组合效应,试验将玉米秸秆青贮、玉米秸秆与桑叶青贮3种饲料以不同比例(分别为100∶0∶0、80∶10∶10、70∶10∶20、70∶20∶10、60∶10∶30、60∶20∶20、60∶30∶10、50∶10∶40、50∶20∶30、50∶30∶20、50∶40∶10、0∶100∶0、0∶0∶100)组合进行发酵(每个组合3次重复),检测不同组合的体外产气量、干物质降解率、氨态氮浓度、pH值和挥发性脂肪酸浓度并分析不同饲料组合的组合效应。结果表明:随着发酵时间的延长,各组合的产气量呈逐渐上升趋势,发酵第2,4小时,组合12(玉米秸秆比例为100%)产气量最高;发酵第8~72小时,组合13(桑叶青贮比例为100%)产气量最高。发酵第72小时,各组合产气量随着桑叶青贮比例的提高而增加,其中组合8(桑叶青贮比例为40%)产气量显著高于其他组合(除组合13外,P<0.05);不同饲料组合对干物质降解率和氨态氮浓度有明显影响,但对pH值影响不明显。当玉米秸秆青贮比例固定时,对应组合干物质降解率随着桑叶青贮比例的增加而增加,组合13的干物质消化率和氨态氮浓度均最高。各组合pH值在6.72~6.81之间,其中组合1(玉米秸秆青贮比例为100%)的pH值最低,组合11(玉米秸秆和桑叶青贮比例分别为40%和10%)最高;乙酸、丙酸、丁酸、总挥发性脂肪酸浓度随着桑叶青贮比例的减少而降低,除组合13外,组合8的乙酸、丁酸、总挥发性脂肪酸浓度最高,各组合丙酸浓度和乙酸/丙酸差异不显著(P>0.05)。多项综合效应指数评定最优组合是组合8。说明玉米秸秆青贮、玉米秸秆、桑叶青贮的比例为50∶10∶40时,体外发酵效果最佳。

木霉微生物菌肥的制备及对玉米茎腐病的应用评价

以前期分离鉴定的生防菌株非洲哈茨木霉Tr35为研究对象,通过载体的筛选,制备木霉菌剂和木霉微生物菌肥。通过测定不同含量的木霉菌剂和木霉有机肥的株高、根长和鲜重,筛选促生效果明显的处理,并通过室内盆栽试验,评价其对玉米苗期茎腐病的防效。结果显示,玉米秸秆粉具有吸水性强、对Tr35无毒和高释放率的优点,与Tr35共同发酵制备木霉菌剂,当土与菌剂为5∶1时,促生效果明显,并对玉米苗期茎腐病防效达51.77%。菌剂土与腐熟羊粪为7∶1时的木霉有机肥促生效果最好,以该比例制备木霉微生物菌肥,对玉米苗期茎腐病防效达61.31%,该研究结果为Tr35菌剂和菌肥的应用开发提供了一定的前期基础。

快速和慢速热解对棉秆生物炭理化特性及土壤持水量的影响

以新疆棉秆为原料,在300~700℃下利用快速和慢速热解方式制备了生物炭,研究了快速和慢速热解对棉秆生物炭形貌、表面官能团、pH值、元素组成的影响.利用室内土柱试验,研究了不同条件下制备的生物炭对土壤持水量的影响.结果表明:1)随着热解温度的升高,生物炭产率下降,pH值提高,孔隙度增加.快速热解生物炭具有孔隙发达、芳香性高、稳定性强的优点.2)土壤持水量随着生物炭添加量和热解温度的升高而提高.生物炭添加量为0.03 g/g时,土壤持水量分别为51.7%和49.7%,比未添加生物炭提高了32.5%和27.4%.3)添加生物炭土壤15 d后保水量仍有40.3%,远高于纯土壤,且添加快速热解生物炭的土壤保水量高于慢速热解生物炭.

汉麻秆芯粉体制备方法的研究进展

由于汉麻本身具有天然的杀菌成分和良好的透湿透气性能,使其在纺织界逐渐受到重视。传统汉麻的外层韧皮纤维利用率较高,但汉麻秆芯则会被当做燃料焚烧或直接作为农业废物填埋掉,这部分大概占汉麻纤维产量的70%~80%。对汉麻秆芯能源的开发利用需要进行粉碎加工处理,以便进一步应用。以汉麻秆芯粉体制备理论、制备方法为研究对象,讨论了锤式粉碎、气流式粉碎、振动式粉碎等工艺技术,为汉麻秆芯粉体的转化利用做好前期处理工序准备。