高分子量谷蛋白（HMW-GS）是决定小麦加工品质的关键种子储藏蛋白类型。Dx5+Dy10是公认的优质HMW-GS组合，但Dy10亚基对加工品质的作用尚不清楚。本研究利用一份Dy10缺失突变体（含Dy10-null等位变异）和体外添加Dy10蛋白的方法研究了Dy10亚基的加工品质效应。Dy10-null等位变异可正常转录，但不表达蛋白。构建近等基因系，发现Dy10-null等位变异显著降低面筋指数、Zeleny沉降值、形成时间和稳定时间，弱化面团强度；降低HMW-GS含量，提高醇溶蛋白含量，降低谷醇比，提升饼干品质。体外添加纯化的Dy10蛋白，发现Dy10对饼干品质有负作用。综上，Dy10亚基与小麦面团强度密切相关，Dy10-null等位变异对弱筋小麦育种具有价值。

为了研究软腐病的抗性基因，我们筛选出了一份易感软腐病大白菜A03、一份抗软腐病小白菜华冠以及一份抗软腐病突变体sr。本研究以感病大白菜A03与抗软腐病小白菜华冠为亲本进行杂交，获得F₂代分离群体来定位大白菜抗软腐病数量性状位点（QTLs）。利用构建的高密度遗传图谱检测到3个QTL位点，共包含166个基因。基于已有的转录组数据，在大白菜受Pc侵染的重要防御调控期，我们对这166个基因在感病大白菜A03和抗病突变体sr内的表达量进行了分析，共筛选出6个候选基因与白菜软腐病防御反应相关。其中，基因TIFY10B (JAZ2，BraA07g038660.3C) 位于A07连锁群的主效QTL位点DRQTL-3上，推测可能是白菜软腐病防御机制中起主效作用的关键基因之一。本研究为进一步研究白菜类作物中软腐病抗性机理奠定了基础。

本研究探讨从华北平原引入优质品种，减少氮肥施用量，提高青藏高原小麦质量和产量的可行性。试验选用青藏高原3个小麦品种和北部冬麦区4个小麦品种，于拔节期减少氮肥追施量，分别在海拔3647 m的青藏高原拉萨和海拔4 m的北部冬麦区河北任丘种植。小麦种在拉萨条件下，北部冬麦区小麦品种相比青藏高原小麦品种表现出较高的籽粒硬度和容重，以及较好的面粉和面团质量。在拔节期将氮肥追施量从135 kg N ha^-1减少到75 kg N ha^-1（氮肥基施量相同，均为105 kg N ha^-1）对两地种植的小麦籽粒产量、籽粒质量、面粉质量、面团质量均没有显着影响（P<0.05）。总体来看，从华北平原引进优质小麦品种到青藏高原种植，并且减少拔节期的氮肥施用量，这是一种提高青藏高原小麦质量的经济实用方法。

本研究通过抗原性分析发现，2020年至2021年在野鸟或家禽中分离的一些H5N6、H5N8和H5N1病毒与我国大规模应用的H5疫苗种毒株(H5-Re11株和H5-Re12株)的抗原性存在较大差异，部分2021年分离的H7N9病毒也与我国使用的H7-Re3株疫苗毒株存在抗原性差异。为保持疫苗株与监测毒株之间良好的抗原匹配性，本研究利用反向遗传学操作技术，构建出针对抗原变异毒株的3株重组疫苗种毒（H5-Re13、H5-Re14和H7-Re4），用于疫苗的更新。其中，H5-Re13疫苗株的HA和NA基因来自于2.3.4.4h分支的H5N6病毒（DK/FJ/S1424/20），H5-Re14疫苗株的HA和NA基因来自于2.3.4.4b分支的H5N8病毒（WS/SX/4-1/20），H7-Re4疫苗株的HA和NA基因来自于2021年分离的H7N9病毒（CK/YN/SD024/21）。进一步使用上述3株重组病毒制备新型H5+H7三价灭活疫苗，进行鸡、鸭和鹅的免疫效力研究。结果显示，H5+H7三价灭活疫苗接种鸡、鸭和鹅后均可诱导出良好的HI抗体反应；SPF鸡接种疫苗后3周时，用2020年和2021年分离到的5株不同H5和H7病毒攻击，包括3株2.3.4.4b分支病毒（H5N1、H5N6和H5N8病毒各1株）、1株2.3.4.4h分支的H5N6病毒和1株H7N9病毒，攻毒后所有对照组鸡均出现高滴度的排毒，并在攻毒后4天内全部死亡，而疫苗接种组鸡则完全抵御病毒的感染；接种疫苗的鸭和鹅在攻击2.3.4.4h或2.3.4.4b分支H5病毒后也获得完全免疫保护。本研究结果表明，新型H5+H7三价疫苗具有良好的免疫原性,对于近期监测到的H5N1、H5N6、H5N8和H7N9病毒的攻击可提供完全的免疫保护作用。鉴于不同H5病毒和H7N9病毒对家禽的威胁，本研究建议我国广泛使用该H5+H7三价灭活疫苗，并推荐该疫苗在其他受到H5和H7病毒威胁的国家应用。

本研究旨在探讨circEDC3对鸡骨骼肌卫星细胞SMSCs增殖、分化和凋亡的调控功能，从而揭示circEDC3在鸡骨骼肌发育中的作用。我们构建了circEDC3的小干扰RNA (siRNA) 及过表达载体(pCD2.1-circEDC3)来调控体外培养的鸡原代骨骼肌卫星细胞中circEDC3的表达水平，通过运用Quantitative Real-Time PCR (qPCR)，Western Blot (WB)，Cell counting kit 8 (CCK-8)，5-Ethynyl-2’-Deoxyuridine (EdU)，flow cytometry，以及immunofluorescence等功能分析方法，检测发现circEDC3能抑制SMSCs增殖、分化相关基因的表达，阻滞细胞周期进程，降低增殖细胞比率，抑制分化相关蛋白的表达，抑制肌管形成，但对SMSCs的凋亡没有明显影响。circRNA通常可以通过靶向微小RNA (miRNAs) 来调控靶基因的表达，然而我们发现circEDC3并未直接靶向肌肉发育相关的miRNAs。此外有研究表明，circRNA可通过直接编码蛋白来调节骨骼肌发育，为了进一步探索circEDC3调控鸡骨骼肌发育的潜在机制，我们对circEDC3的编码能力进行了预测。通过对circEDC3序列信息进行分析，我们发现circEDC3在物种间 (鸡、人、小鼠、大鼠、猪) 保守，且具有不同的开放阅读框、内部核糖体进入位点 (IRES) 和N⁶-甲基腺苷 (m⁶A) 基序，表明circEDC3满足编码蛋白质的前提条件，具备一定程度的编码能力，但这仍需进一步的研究论证。总的来说，我们的研究发现了一个在物种间保守的环状RNA circEDC3，通过分析circEDC3的序列信息，预测该circRNA具有一定的蛋白质编码潜力，通过功能分析试验证明circEDC3是一种新的鸡肌肉发育的负调节因子，提示circEDC3可作为肉鸡分子育种的一个重要候选靶标，为肉鸡的育种改良提供新的切入点。

多巴胺是一种儿茶酚胺和一种抗氧化剂，在应对逆境时起作用，它与植物激素相互作用以介导植物发育。目前，关于苹果中多巴胺功能的研究较少。本研究开发了一种用于分析苹果种质中的多巴胺测定方法，以阐明多巴胺在苹果树的组织分布、发育变化、昼夜变化和逆境响应。首先，对所提出的方法进行了验证，定量的线性范围在0.1-20 ng mL^-1范围内稳定，仪器、日间精密度和样品重复性相对标准偏差分别为1.024%、5.607%和7.237%，加标回收率大于100%，表明该方法的可行性及其适用于快速分析苹果属种质中的多巴胺。接下来，测量了322个苹果组织中的多巴胺含量。结果表明，苹果的多巴胺水平较低，叶片中多巴胺的平均含量高于果皮和果肉。多巴胺在栽培品种和野生种质中向右偏。最后，分析了组织特异性、发育变化、昼夜变化和对逆境的响应。在栽培品种‘皮诺娃’（Malus domestica）中，多巴胺含量在叶芽中最高，在果肉中最低。叶片和果肉中多巴胺含量随着栽培品种‘凉香’（Malus domestica）的生长发育而降低。与对照相比，干旱或盐胁迫后苹果叶片的多巴胺含量更高。在本研究中，建立了一种基于HPLC-MS的苹果多巴胺检测方法，并证明是一种稳健的方法。本研究为未来阐明苹果树中多巴胺的组织分布、发育变化、昼夜变化和逆境响应提供了一个框架。

双酰胺衍生物近年来在农药（特别是杀虫剂）的研究中被广泛关注。本文通过简单、环保的合成路线，设计、合成了一系列含有三氟甲基吡啶骨架的新型双酰胺衍生物，通过1H、19F和13C NMR以及HR-MS进行了确证。并测定了它们对小菜蛾（Plutella xylostella）和棉铃虫（Helicoverpa armigera）的杀虫活性，讨论了构效关系。部分化合物（D2、D5、D10、D21、D28、D29、D30和D33）在500 mg·L^-1时对小菜蛾具有100%杀虫活性。其中，化合物D33在100 mg·L^-1时对具有100%的杀虫活性，其LC₅₀值（致死中浓度）为3.7 mg L^-1，为该类化合物中最低值。分子对接结果表明，D33可嵌入鱼尼丁受体的活性口袋中，与商业杀虫剂氯虫苯甲酰胺类似，通过多个氢键与鱼尼丁受体相互作用。

为了阐明海河平原冬小麦春季限制灌溉的最佳时期及其对旗叶衰老和产量形成的影响，2016年至2019年，研究组在河北农业大学辛集试验站进行了不同灌溉模式的田间试验，试验包括两种灌溉模式：对照（CK，分别在3叶展开期和开花期浇水）和单一限制灌溉（SRI），后者又包括3叶展开期（3LI）、4叶展开期（4LI）、5叶展开期（5LI）和6叶展开期（6LI）灌溉。结果表明：（1）与对照相比，4LI处理组在一定程度上衰老进程（用绿叶面积表示）提前，而5LI和6LI处理组之间的差异不显著，衰老发生明显晚于3LI处理组；（2）与其他SRI处理组相比，4LI处理组的GLA值和光合速率分别提高了14.82%和20.1%。旗叶显微结构分析还表明，干旱胁迫下3LI和6LI处理组的叶肉细胞和叶绿体排列不规则，但这种胁迫对4LI和5LI处理组的微观结构的负面影响很小；（3）春季延迟灌溉在籽粒灌浆前期可显著增加超氧化物歧化酶（SOD）和过氧化氢酶（CAT）活性，随后酶的活性逐渐降低。在4个SRI处理组中，4LI处理组的总酶活性最高，4LI和5LI处理组的旗叶MDA含量平均比3LI和6LI处理组的MDA含量低14.5%；（4） 可溶性糖（SS）和脯氨酸（Pro）含量以4LI处理组最高，但低于CK组。4LI和5LI处理组的ABA激素含量低于3LI和6LI处理组，说明4LI和5LI处理组遭受的干旱胁迫程度较小；（5）在两个生长季，4LI处理组的单位面积穗数较多（比5LI和6LI处理组高13.4%），且千粒重最高（比其他三种SRI处理组高6.0%）。因此，4LI处理组的冬小麦产量在四个SRI处理组中最高。综合分析，建议4LI处理组（即在春季4叶期进行一次灌水）能有效延缓旗叶衰老进程，并使冬小麦保持相对较高的产量。

丝束蛋白（fimbrin）是肌动蛋白细胞骨架的调节因子，参与并控制多种组织和细胞的生理生化和发育过程。然而，fimbrin在对病原菌防御中，特别是在小麦抗条锈病中的作用研究匮乏，其机制尚待阐明。本研究以小麦品种水源11（Suwon 11）与条锈菌（Puccinia striiformis f. sp. tritici，Pst）生理小种CYR23组成非亲和互作，与生理小种CYR31组成成亲和互作，利用实时荧光定量 PCR 技术（qRT-PCR）对TaFIM1基因参与小麦抗条锈病的功能进行初步分析；对在非生物胁迫和施用外源激素处理TaFIM1基因的表达特征进行分析；通过病毒诱导的基因沉默（BSMV-VIGS）技术，验证TaFIM1在小麦抗条锈病中的功能。获得以下研究结果：TaFIM1在非亲和互作中的表达量显著上调，且在48 h表达量达到峰值，是对照0 h的6.0倍；在亲和互作中，TaFIM1的表达量无明显变化。TaFIM1能够响应不同非生物胁迫，在高温（Hot）、低温（Cool）、盐（NaCl）和干旱（PEG6000）胁迫下诱导TaFIM1基因表达量上调。BSMV-VIGS试验结果显示，借助大麦条纹花叶病毒对TaFIM1基因进行诱导沉默。对沉默成功的小麦植株分别接种条锈菌CYR23和CYR31。在非亲和互作中，沉默植株的抗病性降低，叶片上出现少量的夏孢子堆；在亲和互作中，与对照相比，叶片上的夏孢子堆数量增加，沉默植株的感病性增强。组织学观察发现，在48 h和120 h，TaFIM1沉默植株叶片中菌丝分支数和菌丝长度高于对照，在120 h基因沉默植株叶片中菌落面积显著高于对照组，表明TaFIM1沉默后小麦植株与对照相比感病性增强，进一步说明TaFIM1参与植物的抗病性。因此，TaFIM1与植物抗病性相关，在小麦抵抗条锈病的侵染过程中响应正调控作用。本研究为理解fimbrin在小麦中的作用提供了新的见解。

萝卜是一种重要的十字花科根菜类蔬菜作物，在其有色的根中有高水平的花青素累积。MYB转录因子(TFs)在植物发育和花青素代谢中起着重要作用，并且PAP1/2能促进花青素生物合成基因的表达。本研究在萝卜基因组中共鉴定出187个RsMYB基因，并将其分为32个亚家族；其中159个RsMYB基因被定位在9条染色体上。在4个不同颜色的萝卜品种肉质根发育阶段，14个RsMYB基因表现出差异的表达模式。一些RsMYB基因在成熟期有色根组织中高表达，这些基因包括RsMYB41，RsMYB117以及与PAP1/2同源的RsMYB132在‘NAU-YH’的红色根皮中高表达，RsMYB65和RsMYB159基因在‘NAU-YZH’的紫色根皮中高表达，表明这些RsMYB基因可能促进萝卜肉质根花青素积累。研究结果为进一步研究萝卜RsMYB基因功能特性提供有价值的信息，并有助于阐明萝卜花青素生物合成的分子机制。

Wheat was the first crop grown in Egypt, and it remains highly important.  Egypt is the largest wheat importer in the world and consumes an extensive amount of bread.  It is imperative for wheat scientists to decrease the large gap between production and consumption.  Wheat yields in Egypt increased 5.8-fold (6.7 billion kg) between 1961 and 2017 due to variety improvement and the use of better planting methods such as the raised bed method, ideal sowing date, surge flow irrigation and farm irrigation systems, laser levelling, fertilizers, and intercropping with raised beds.  In this paper, the development of wheat production techniques and variety evolution over more than five decades in Egypt have been analyzed.  In particular, we have focused on the technologies, cultural practices and causes for per unit area yield increase.  The main purpose was to study the issues that have arisen during wheat production and to make recommendations for smart agricultural practices.  In 1981, the yield was 3 300 kg ha^–1 and through the improvement of varieties, expansion of agricultural land and the adoption of modern agricultural techniques yield reached 6 500 kg ha^–1 by 2017.  The production growth rate was 4.1% annually, and the total grain yield increased 4.3-fold, from 1.9 billion kg in 1981 to about 8.1 billion kg in 2017.  The use of new improved varieties, new cultivation techniques, and modern irrigation techniques contributed to 97.0% of the increase in yield per unit area and 1.5% of the increase in yield was due to planting area expansion.  Therefore, the increase in total yield mainly depended on the increase in yield per unit area.  Wheat production in Egypt has been improved through the development of breeding and cultivation techniques.  The use of these new techniques, the popularization of new high-quality seed varieties, and the use of the raised bed method instead of the old method of planting in basins have made the largest contributions to increased yield.  In the future, wheat yield could be further increased by using the tridimensional uniform sowing mode and the development of wheat varieties that are resistant to rusts, deficit irrigation, and abiotic stress, that are highly adaptable to mechanized operation and have high yields.  Based on our analysis, we propose the main technical  requirements and measures to increase wheat yield in Egypt in the near future.

It is generally known that the culture for mycoplasma is time-consuming and a variety of nutrients are needed in the culture medium.  This brings a lot of difficulties to mycoplasma research and application, including Mycoplasma mycoides subsp. capri (Mmc).  Furthermore, little research on the characteristics of Mmc metabolism has been reported.  In this study, Mmc PG3 strain cultures were investigated for dynamic gene expression.  Culture samples were harvested during logarithmic phase (PG3-1), stationary phase (PG3-2), decline phase (PG3-3) and late decline phase (PG3-4).  Twelve RNA samples (three replicates for each of the four growth stages considered) from these cultures were collected and sequenced.  Paired comparison between consecutive growth phases in the four growth stages showed 45 significant differentially expressed genes (P<0.01) were linked to PG3 metabolism.  The enzymes these genes coded were mainly involved in ATP synthase, pyrimidine metabolism, nicotinate and nicotinamide metabolism, arginine and proline metabolism.  Among these, cytidylate kinase, fructose 1,6-bisphosphate aldolases Class II, nicotinate-nucleotide adenylyltransferase and dihydrolipoamide dehydrogenase play a key role in Mmc metabolism.  These results provide a baseline to build our understanding of the metabolic pathway of Mmc.  

A study was conducted in attempting to identify the cold-resistant apple rootstocks and to establish a comprehensive evaluation system.  In this study, 10 elite apple dwarfing rootstocks (GM256, JM7, M26, M7, SC1, SH1, SH38, SH6, M9, and T337) were employed for the experiment and the following parameters were investigated under different low temperature stress conditions (0, –15, –20, –25, –30, and –35°C): the changes of the relative electrical conductivity (REC), anthocyanin content, protein content, soluble sugar content, soluble starch content, proline content, malondialdehyde (MDA) content, superoxide dismutase (SOD) activity, and peroxidase (POD) activity of the dormant branches.  The inflection temperature that could represent the plant tissue semi-lethal temperature (LT₅₀) was obtained by the measurements of REC.  The LT₅₀ was used to evaluate eight other indices.  The results showed that there was no significant correlation between LT₅₀ and POD activity as well as between the soluble sugar, protein and proline contents at 0 and –15°C.  Soluble starch content at 0 and –15°C and anthocyanin content at –15–(–30)°C were significantly but negatively correlated to the LT₅₀ and the MDA content at 0–(–20)°C was significantly positively correlated to the LT₅₀.  Statistical analysis based on principal component analysis and LT₅₀ showed that cold resistant apple rootstocks in the decreasing order from high to low as GM256, SH6, SH38, SH1, SC1, M26, M7, JM7, T337, and M9.

Domestic pigs are the second most important source of meat world-wide, and the genetic improvement of economic traits, such as meat production, growth, and disease resistance, is a critical point for efficient production in pigs.  Through conventional breeding and selection programs in pigs, which are painstakingly slow processes, some economic traits, such as growth and backfat, have been greatly improved over the past several decades.  However, the improvement of many polygenetic traits is still very slow and challenging to be improved by conventional breeding strategies.  The development of reproductive knowledge and a variety of techniques, including foreign gene transfer strategies, somatic cell nuclear transfer (SCNT) and particularly, recently developed nuclease-mediated genome editing tools, has provided efficient ways to produce genetically modified (GM) pigs for the dramatic improvement of economic traits.  In this review, we briefly discuss the progress of genomic markers used in pig breeding program, trace the history of genetic engineering, mainly focusing on the progress of recently developed genome editing tools, and summarize the GM pigs which have been generated to aim at the agricultural purposes.  We also discuss the specific challenges facing application of gene engineering in pig breeding, and future prospects.

   The variant LM1 was previously obtained using embryogenic cell suspension cultures of sweetpotato variety Lizixiang by gamma-ray induced mutation, and then its characteristics were stably inherited through six clonal generations, thus this mutant was named LM1. In this study, systematic characterization of salt tolerance and Fusarium wilt resistance were performed between Lizixiang and mutant LM1. LM1 exhibited significantly higher salt tolerance compared to Lizixiang. The content of proline and activities of superoxide dismutase (SOD) and photosynthesis were significantly increased, while malonaldehyde (MDA) and H₂O₂ contents were significantly decreased compared to that of Lizixiang under salt stress. The inoculation test with Fusarium wilt showed that its Fusarium wilt resistance was also improved. The lignin, total phenolic, jasmonic acid (JA) contents and SOD activity were significantly higher, while H₂O₂ content was significantly lower in LM1 than that in Lizixiang. The expression level of salt stress-responsive and disease resistance-related genes was significantly higher in LM1 than that in Lizixiang under salt and Fusarium wilt stresses, respectively. This result provides a novel and valuable material for improving the salt tolerance and Fusarium wilt resistance of sweetpotato.

Mitogen-activated protein kinase (MPK) cascades consist of a set of kinase types (MPKKKs, MPKKs, MPKs) to establish
conserved signal-transducing modules mediating plant growth, development as well as responses to internal and external
cues. In this study, the expression patterns of six MPKKK, two MPKK, and 11 MPK genes in wheat in responses to external
treatments of phytohormones, including naphthylacetic acid (NAA), abscisic acid (ABA), 6-benzyladenine (6-BA), gibberellin
(GA^₃), salisylic acid (SA), jasmonic acid (JA), and ethylene (ETH), were investigated. Expression analysis revealed
that several of the MPK cascade genes are responses to the external phytohormone signaling. Of which, TaMPKKKA;3
is induced by 6-BA and NAA while TaMPK4 repressed by ETH, GA_3, SA, and JA; TaMPKKKA, TaMPKKKA;3 and TaMPK1
are down-regulated by ETH and GA^₃ whereas TaMPK9 and TaMPK12 repressed by ETH and JA in addition that TaMPK12
also repressed by GA_3; TaMPK12;1 is down-regulated by ABA, GA₃ and SA while TaMPK17 repressed by all exogenous
phytonormones examined. TaMPK4, a MPK type gene previously characterized to mediate tolerance to phosphate (Pi)
deprivation, was functionally evaluated for its role in mediation of responses of plants to exogenous GA₃, ETH, SA, and JA.
Results indicated that overexpression and antisense expression of TaMPK4 in tobacco dramatically modify the growth of
seedlings upon treatments of GA₃, SA and JA, in which the overexpressors behaved deteriorated growth feature whereas
the seedlings with antisense expression of TaMPK4 exhibited improved seedling phenotype. The growth behaviors in
lines overexpressing or antisensely expressing TaMPK4 are closely associated with the biomass and the corresponding
hormone-associated parameters. These results demonstrated that TaMPK4 acts as a critical player in mediating the phytohormone
signaling. Our findings have identified the phytohormone-responsive MPK cascade genes in wheat and provided
a connection between the phytohormone-mediated responses and the MPK cascade pathways.

    A plastidic adenosine triphosphate (ATP)/adenosine diphosphate (ADP) transporter (AATP) is responsible for importing ATP from the cytosol into plastids. In dicotyledonous plants, increasing ATP supply is a potential way to facilitate anabolic synthesis in heterotrophic plastids. In this study, a gene encoding the AATP protein, named IbAATP, was isolated from sweetpotato (Ipomoea batatas (L.) Lam.). Transcripts of IbAATP were predominantly detected in the storage roots and leaves and were induced by exogenous sucrose and subjected to circadian rhythm. Transient expression of IbAATP in tobacco and onion epidermal cells revealed the plastidic localization of IbAATP. The overexpression of IbAATP in sweetpotato significantly increased the starch and amylose contents and led to enlarged starch granules. The IbAATP-overexpressing plants showed altered fine structure of amylopectin, which contained an increased proportion of chains with a degree of polymerization (DP) of 10–23 and a reduced number of chains with a DP of 5–9 and 24–40. In addition, starch from the transgenic plants exhibited different pasting properties. The transcript levels of starch biosynthetic genes, including IbAGP, IbGBSSI, IbSSI-IV, and IbSBE, were differentially regulated in the transgenic plants. These results revealed the explicit role of IbAATP in the starch biosynthesis of sweetpotato and indicated that this gene has the potential to be used to improve starch content and quality in sweetpotato and other plants.

    A fast analytical method for the simultaneous determination of 9 mycotoxins, including aflatoxins (B₁, B₂, G₁, and G₂), fumonisins (B1, B2 and B3), zearalenone, and deoxynivalenol in corn using dispersive solid-phase extraction method and ultra-performance liquid chromatography coupled to tandem quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) was developed and validated. Samples were extracted with acetonitrile-water (84:16, v:v, containing 1% acetic acid) using ultrasonic extraction. The extracts were purified with a dispersive SPE method using C18 as a cleaning agent. The final clear extracts were dried by nitrogen blowing and subsequently redissolved in methanol-water (5:5, v:v). The samples were then analyzed by UPLC-Q-TOF-MS with 0.1% formic acid in ammonium acetate-methanol as mobile phase. The mean recoveries were ranged from 68.0 to 120.0%, and the relative standard deviation (RSD) ranged from 0.18 to 6.29%. Limits of detections ranged from 0.05 to 50 μg kg⁻¹, and limits of quantification ranged from 0.1 to 200 μg kg⁻¹, which were below the legal limits set by the European Union for the legislated mycotoxins. The developed method was applied to 130 corn samples. Among the mycotoxins studied, aflatoxins B₁ and fumonisins B₁, B₂ and B₃ were the most predominant mycotoxins, and their concentrations were 0–593.12, 0–2.01×10⁴, 0–6.94×10³ and 0–3.05×10³ µg kg^–1, respectively.

Understanding the sequence diversity of rice blast resistance genes is important for breeding new resistant rice cultivars against the rice blast fungus Magnaporthe oryzae. In this study, we selected 24 rice cultivars with different genetic backgrounds to study the allelic diversity of rice blast resistance genes Piz-t, Pita and Pik. For Piz-t, a total of 17 allelic types were found within the 24 cultivars. Blast inoculations showed that most of the mutations can affect the function of the resistance gene. For Pita, except for the difference at the 918th amino acid, a majority of the 21 mutations were detected among the cultivars. Inoculations with blast isolates carrying Avr-Pita revealed that cultivars with mutations in other sites except for the 918th amino acid did not affect the function of the Pita gene. For Pik, a total of six allelic types were found within the 24 cultivars, but five of them lost the function of the resistance gene. In addition, we found that Piz-t, Pita and Pik were expressed constitutively in the 24 rice cultivars and the expression level was not related to resistance. Our results have provided the sequence diversity information of the resistance genes Piz-t, Pita and Pik among the popular rice cultivars grown in the northeast region of China.

Both bolting and flowering times influence taproot and seed production in radish. FLOWERING LOCUS C (FLC) plays a key role in plant flowering by functioning as a repressor. Two genomic DNA sequences, a 3 046-bp from an early- and a 2 959-bp from a late-bolting radish line were isolated and named as RsFLC1 and RsFLC2, respectively, for they share approximately 87.03% sequence identity to the FLC cDNA sequences. The genomic DNA sequences, 1 466-bp and 1 744-bp, flanking the 5´-regions of RsFLC1 and RsFLC2, respectively, were characterized. Since both of them harbor the basic promoter elements, the TATA box and CAAT box, they were designated as PRsFLC1 and PRsFLC2. The transcription start site (TSS) was identified at 424 and 336 bp upstream of the start codon in PRsFLC1 and PRsFLC2, respectively. cis-regulatory elements including CGTCA (MeJA-responsive) and ABRE (abscisic acid-responsive) motifs were found in both promoters, while some cis-regulatory elements including TCA element and GARE-motif were present only in PRsFLC1. These sequence differences lead to the diversity of promoter core elements, which could partially result in the difference of bolting and flowering time in radish line NauDY13 (early-bolting) and Naulu127 (late-bolting). Furthermore, to investigate the activity of these promoters, a series of 5´-deletion fragment-GUS fusions were constructed and transformed into tobacco. GUS activity was detected in PRsFLC1-(1 to 4)-GUS-PS1aG-3 and PRsFLC2-(1 to 4)-GUS-PS1aG-3 transgenic tobacco leaf discs, and this activity progressively decreased from PRsFLC-1-GUS-PS1aG-3 to PRsFLC-5-GUS-PS1aG-3. Deletion analysis indicated that the cis-regulatory elements located at –395 bp to +1 bp may be critical for specifying RsFLC gene transcription.

    The objective of this study was to isolate lactic acid bacteria (LAB) strains from different origins and to select the best strains for ensiling Robinia pseudoacacia (RB) and Morus alba L. (MB) leaves. The LAB strains were inoculated into the extracted liquid obtained from RB and MB leaves to evaluate the fermentation products. 11 LAB strains were selected for further experiments based on the highest products of lactic or acetic acid, including 1 strain of Weissella confusa, 2 of Lactobacillus reuteri and 8 of Lactobacillus plantarum. The API 50 CH fermentation experiment indicated that all of the selected 11 LAB strains utilised most of the carbohydrates. All the strains grew at temperatures between 10 and 45°C and at a pH of 3.5 to 4.5; however, L. reuteri F7 and F8 tolerated a pH as low as 3.0. All 11 LAB strains showed antibacterial activity against Listeria monocytogens, Escherichia coil, Salmonella sp. and Acetobacter pasteurianus; however, after excluding the effect of organic acids, only F7 and F8 still exhibited antibacterial activity. The present study indicated that the selected 11 LAB strains could be used to prepare silages of RB and MB leaves, especially L. reuteri F7 and F8.

    Covered smut, which is caused by Ustilago hordei (Pers.) Lagerh., is one of the most damaging diseases of highland barley (Hordeum vulgare Linn. var. nudum Hook. f) in Tibetan areas of China. To understand the molecular diversity of U. hordei, a total of 27 isolates, which were collected from highland barley plants from Tibet, Sichuan, Qinghai, and Gansu provinces/autonomous region, were analyzed using random amplified polymorphic DNA (RAPD) and simple sequence repeat (SSR) markers. Among the 100 RAPD primers used, 24 primers exhibited polymorphism. A total of 111 fragments were amplified, of which 103 were polymorphic with a polymorphic rate of 92.79%. The average observed number of alleles (Na), effective number of alleles (Ne), Nei’s genetic diversity (H), Shannon’s information index (I) and polymorphism information content (PIC) value in the RAPD markers were 1.9279, 1.5016, 0.2974, 0.4503 and 0.6428, respectively. For the SSR markers, 40 of the 111 primer pairs exhibited polymorphism and provided a total of 119 bands, of which 109 were polymorphic and accounted for 91.60% of the total bands. The Na, Ne, H, I and PIC values of the SSR markers were 1.9160, 1.4639, 0.2757, 0.4211 and 0.4340, respectively. The similarity coefficients ranged from 0.4957 to 0.9261 with an average of 0.7028 among all the 27 isolates used. The dendrogram, which was developed based on the RAPD and SSR combined marker dataset showed that the 27 U. hordei isolates were divided into 3 clusters at similarity coefficient of 0.7314. We determined that RAPD and SSR markers can be successfully used to assess the genetic variation among U. hordei isolates. The RAPD markers revealed higher levels of genetic polymorphism than did the SSR markers in this study. There existed a moderate genetic difference among isolates. The molecular variation and differentiation was somewhat associated with geographical origin but not for all of the isolates.

    Considering the advantages of single nucleotide polymorphisms (SNP) in genotyping and variety identification, the first set public SNP markers at Cotton Marker Database (http://www.cottonmarker.org/) were validated and screened across standard varieties of cotton distinctness, uniformity and stability (DUS) test, aiming to obtain an appropriate set of core SNP markers suitable for upland cotton cultivars in China. A total of 399 out of 1 005 SNPs from 270 loci including 170 insertions-deletions (InDels) were evaluated for their polymorphisms among 30 standard varieties using Sanger sequencing. As a result, 147 loci were sequenced successfully, 377 SNPs and 49 InDels markers were obtained. Among the 377 SNP markers, 333 markers (88.3%) were polymorphic between Gossypium hirsutum and G. barbadense, while 164 markers (43.5%) were polymorphic within upland cotton. As for InDel markers, the polymorphic rate is relatively lower than that of SNP both between species and within species. The homozygous DNA locus ratio of 121 SNPs was higher than 86.2% while that of other 43 SNPs was less than 70%. Only 64 SNPs displayed completely homozygous genotypes among all of the detected upland cotton varieties with 100% homozygous DNA locus ratio. At last, a set of 23 pairs of core SNPs were achieved in view of avoidance of linkage, with polymorphism information content (PIC) values varying from 0.21 to 0.38 with an average of 0.28. Genotype characteristics and genetic diversity were analyzed based on the set of core markers, while 40 pairs of core simple-sequence repeats (SSR) primers comprised of 10 sets of four multiplex PCR combinations were also used for analysis based on fluorescence detection system. Comparison results indicated that the genetic diversity level was almost equal, while various varieties were significantly different from each other. Genetic relationship revealed by SSR markers is related to geographic source to a certain extent. Meanwhile clustering results analyzed by SNP markers are more consistent with kinship, which demonstrated that the screen strategy for core SNP marker is effective.

Nitrogen (N) is one of the macronutrients required for plant growth, and reasonable application of N fertilizers can increase crop yields and improve their quality. However, excessive application of N fertilizers will decrease N use efficiency and also lead to increases in N2O emissions from agricultural soils and many other environmental issues. Research on the effects of different N fertilizer management practices on wheat yields and N2O emissions will assist the selection of effective N management measures which enable achieving high wheat yields while reducing N2O emissions. To investigate the effects of different N management practices on wheat yields and soil N2O emissions, we conducted field trials with 5 treatments of no N fertilizer (CK), farmers common N rate (AN), optimal N rate (ON), 20% reduction in optimal rate+dicyandiamide (ON80%+DCD), 20% reduction in optimal rate+nano-carbon (ON80%+NC). The static closed chamber gas chromatography method was used to monitor N2O emissions during the wheat growing season. The results showed that there were obvious seasonal characteristics of N2O emissions under each treatment and N2O emissions were mainly concentrated in the sowing- greening stage, accounting for 54.6–68.2% of the overall emissions. Compared with AN, N2O emissions were decreased by 23.1, 45.4 and 33.7%, respectively, under ON, ON80%+DCD and ON80%+NC, and emission factors were declined by 22.2, 66.7 and 33.3%, respectively. Wheat yield was increased significantly under ON80%+DCD and ON80%+NC by 12.3 and 11.9%, respectively, relative to AN while there was no significant change in yield in the ON treatment. Compared with ON, overall N2O emissions were decreased by 29.1 and 13.9% while wheat yields improved by 18.3 and 17.9% under ON80%+DCD and ON80%+NC, respectively. We therefore recommend that ON80%+DCD and ON80%+NC be referred as effective N management practices increasing yields while mitigating emissions.

Mycotoxin contamination in agro-food systems has been a serious concern globally during the last few decades. Mycotoxins are toxic secondary metabolites produced by fungi when they grow in agro-food products and feedstuff. Several detection techniques have been developed in recent years to detect mycotoxins in the food and feed effectively. HPLC based techniques are very common in usage in the laboratories for the testing of mycotoxins. In recent years, immuno-based assays is widely used and have been reported at large due to its sensitivity and limited detection time. Immuno assay-based kits were developed effectively to be used in the fields and in storage systems to detect the mycotoxin levels. Microarray-based immunoassays developed in the recent years could simultaneously detect aflatoxin, ochratoxin, and zearalenone with the higher sensitivity. Aptamer-based assays could target the detection of ochratoxin and aflatoxins and fumonisins at high specificity in food products. In recent years, several assays reported for the simultaneous multiple detection of different mycotoxin was based on HPLC and LC-MS/MS. There is a need for the use of these advanced technologies in the commercial scale.