氮肥运筹对豫中地区冬小麦旗叶生理及籽粒产量的影响

为探讨豫中地区冬小麦合理高效的氮肥运筹模式,以百农矮抗58为试验材料,采用裂区试验设计,研究了氮肥施用量及运筹模式对冬小麦旗叶生长生理及籽粒产量的影响。结果表明,氮肥运筹对冬小麦旗叶叶绿素含量、净光合速率、硝酸还原酶活性及可溶性蛋白含量的影响均达显著水平。随施氮总量的增加,旗叶叶绿素含量、净光合速率和可溶性蛋白含量均表现不同程度的升高,硝酸还原酶活性也保持较高值。在基肥相同的条件下,增加拔节期追氮量能显著提高旗叶叶绿素含量、净光合速率、硝酸还原酶活性和可溶性蛋白含量。施氮总量相同时,拔节期追氮量较多的处理对基施氮肥较少的处理有一定的补偿效应。氮肥运筹对籽粒产量的影响达极显著水平,其中N120＋150模式下的穗粒数及粒重最高,N120＋210模式下小麦成穗数及籽粒产量最高。综上,豫中地区生态环境下,施纯氮270 kg.hm-2,其中基施氮肥120 kg.hm-2、拔节期追施氮肥150 kg.hm-2的N120＋150处理是较为合理的氮肥运筹模式。     

施氮对冬小麦旗叶蔗糖含量及籽粒淀粉合成的影响

为给小麦高产优质栽培提供依据,在高产田块上,设置三个氮肥用量(90、180、270 kg N·ha-1),研究了施氮对两个冬小麦品种豫麦49和太空6号开花后旗叶蔗糖、籽粒淀粉合成动态及产量的影响.结果表明,施氮对两品种旗叶蔗糖含量及SPS酶活性、籽粒蔗糖含量及SS酶活性、籽粒淀粉积累速率及产量均有显著影响,但影响特点因品种而异.豫麦49在施氮量90～270 kg·ha-1范围内,随施氮量的增加,旗叶和籽粒的蔗糖含量、SPS和SS活性以及籽粒淀粉积累速率均呈增加趋势.太空6号在施氮90～180 kg·ha-1范围内,上述指标在灌浆中后期与施氮量呈正相关;当氮肥用量增加至270 kg·ha-1时,各项指标均下降.相关分析表明,两供试冬小麦品种籽粒蔗糖含量与旗叶蔗糖含量分别呈极显著和显著正相关(豫麦49 r=0.703**,太空6号r=0.530*);豫麦49籽粒淀粉积累速率与其籽粒蔗糖含量和SS活性之间呈显著和极显著正相关(r=0.578*,r=0.701**),太空6号籽粒淀粉积累速率仅与籽粒SS之间呈显著的正相关(r=0.625*),而与籽粒蔗糖含量之间相关性不显著(r=0.121).施氮量270 kg·ha-1时,豫麦49产量最高;太空6号需氮量相对较低,产量达最大值时的施氮量为180 kg·ha-1.     

追氮时期对强筋小麦产量、品质及其相关生理指标的影响

为研究追氮时期对强筋小麦产量、品质及相关生理指标的影响,以强筋小麦济麦20为材料在大田进行不同追氮时期的试验.结果表明,在总施纯氮量270 kg/ha、基追比为5:5的条件下,不同时期追施氮肥对小麦籽粒蛋白质含量、籽粒产量以及旗叶的生理指标有一定的调节作用.后期追施氮肥有利于抑制旗叶叶绿素的降解,提高旗叶硝酸还原酶的活性,延长旗叶的功能期,且以开花期追氮最为显著.旗叶展开21～28d时,叶片的叶绿素含量和硝酸还原酶活性分别与粒重和籽粒蛋白含量具有显著的相关性.籽粒总蛋白质含量随着追氮时期的后移而增加,并于开花期达到最大值.籽粒蛋白组分的含量有随追氮时期的后移而增加的趋势,最大值集中出现在春5叶～开花这一时期.开花期追施氮肥有利于籽粒产量和籽粒蛋白质产量的协同提高.为实现高产和优质的统一,强筋小麦在开花期追施氮肥较为合适.     

施氮量对小麦旗叶光合速率和光化学效率、籽粒产量与蛋白质含量的影响

为给小麦高产高效栽培提供依据,在大田高产条件下,研究了施氮量对开花后小麦旗叶光合速率和光化学效率、旗叶和籽粒蔗糖含量及籽粒产量和蛋白质含量的影响。结果表明,适量施氮有利于提高灌浆中、后期的旗叶光合速率、旗叶PSⅡ实际光化学效率,以及灌浆末期旗叶PSⅡ最大光化学效率;施氮过多不仅不能继续提高旗叶光合速率,而且使PSⅡ实际光化学效率降低。施氮有利于提高旗叶蔗糖含量,促进灌浆前期籽粒中蔗糖的供应;施氮较多的处理中,灌浆后期有较多蔗糖滞留于旗叶中,致使施氮处理间籽粒蔗糖含量无显著差异。与不施氮的处理相比较,施氮105~195 kg.ha-1显著提高籽粒产量,施氮105~240 kg.ha-1显著提高籽粒蛋白质含量;继续增施氮肥至285 kg.ha-1,籽粒蛋白质含量、粒重和籽粒产量均降低。综合考虑籽粒产量和蛋白质含量,施氮量以150~195 kg.ha-1为宜。     

豫东潮土氮钾营养对强筋小麦旗叶生理特性和籽粒品质的影响

为给豫东潮土区强筋小麦优质高产栽培提供理论依据,在壤质土壤施用磷肥的基础上,采用裂区设计,研究了氮肥和钾肥配施对强筋小麦旗叶硝酸还原酶活性、光合特性和籽粒品质的影响。结果表明,氮钾肥配合施用条件下,除抽穗期施氮量和施钾量与强筋小麦旗叶硝酸还原酶活性分别呈直线和二次曲线关系外,氮、钾肥用量与其余时期旗叶硝酸还原酶活性以及各时期旗叶光合速率、蒸腾速率和气孔导度等生理指标均呈二次曲线关系,对硝酸还原酶活性的影响存在着正交互作用,其中N₂₇₀K₁₅₀［施氮(纯氮)和施钾（K₂O）量分别为270和150 kg·hm^-2］处理,各生理指标表现最高。氮、钾肥用量与强筋小麦沉降值、面团稳定时间、面团形成时间和弱化度等品质指标呈二次曲线关系,并存在着正交互作用;粗蛋白和湿面筋含量与施氮量呈直线关系,与施钾量呈二次曲线关系。说明氮钾配施对强筋小麦硝酸还原酶活性、光合特性的影响与对品质的影响基本一致。在本试验条件下,植株生理和籽粒品质达到最佳的处理为N₂₇₀K₁₅₀,适宜的N∶K₂O为1.8∶1。     

灌水对不同穗型小麦碳氮代谢及籽粒灌浆的影响

为了给小麦节水栽培实践提供参考,在大田条件下研究了灌水次数对大穗型小麦品种豫麦66与多穗型小麦品种豫麦49碳氮代谢及籽粒灌浆的影响。结果表明,增加灌水次数可以提高旗叶硝酸还原酶(NR)活性和可溶性蛋白质含量,在灌浆中后期豫麦66较豫麦49具有明显优势。随着灌水次数增加,旗叶和籽粒可溶性糖含量在灌浆前期降低,而在灌浆后期籽粒可溶性糖含量升高,旗叶则表现相反。籽粒淀粉积累速率在灌浆前期随灌水次数增加而降低,但在灌浆后期则与之相反。籽粒灌浆速率呈单峰曲线变化,增加灌水次数,积累高峰期推迟,且前期慢,后期快,在花后35 d豫麦66在灌一水、灌两水和灌三水处理下籽粒灌浆速率分别为0.96、1.24和1.07 mg/d,而豫麦49分别为0.94、0.39和0.36 mg/d。豫麦66与豫麦49号相比,旗叶可溶性糖含量在灌浆中后期较低,淀粉及籽粒积累速率的峰值出现较晚但持续时间较长,表明大穗型品种同化物外运能力和库活性较强,灌浆进程稳健。     

氮素和钾素胁迫对去顶烤烟生理指标及烟碱的影响

以烤烟K326为材料,采用盆栽砂培试验研究了打顶后缺氮、缺钾对烤烟叶绿素含量、硝酸还原酶活性、根系活力等生理指标及烟碱含量的影响。结果表明：打顶后氮、钾胁迫对烤烟生理指标及烟碱含量都有较大的影响,在叶绿素含量、硝酸还原酶活性、根系活力等方面大致表现为全素〉缺钾〉缺氮处理,而烟碱含量表现为缺钾〉全素〉缺氮处理,并且各处理之间存在显著差异。总体而言,氮、钾胁迫不利于烤烟的生长发育。     

不同形态氮素对弱筋小麦籽粒淀粉积累及其相关酶活性的影响

为给弱筋小麦优质高产高效栽培的合理氮肥运筹提供理论依据,在大田条件下研究了3种形态的氮素(酰胺态氮、铵态氮和硝态氮)对弱筋小麦豫麦50籽粒淀粉合成及其相关酶活性的影响.结果表明,施铵态氮能增加灌浆中后期籽粒总淀粉和支链淀粉积累量,保持较高的籽粒总淀粉和支链淀粉积累速率,而施酰胺态氮籽粒直链淀粉积累量和积累速率较高.施铵态氮有利于提高成熟期籽粒总淀粉、支链淀粉含量和支/直比例,而施酰胺态氮提高了直链淀粉含量.施硝态氮对小麦籽粒淀粉积累的调控效应介于施铵态氮和施酰胺态氮之间.施铵态氮和施硝态氮后旗叶蔗糖合成酶(SS)和灌浆中后期蔗糖磷酸合成酶(SPS)活性高,灌浆中后期籽粒蔗糖合成酶(SS)活性、籽粒蔗糖含量、可溶性淀粉合成酶(SSS)活性高,束缚态淀粉合成酶(GBSS)活性低,而施酰胺态氮则表现出相反的趋势.施硝态氮的旗叶蔗糖含量始终最低;与施酰胺态氮相比,施铵态氮旗叶蔗糖含量灌浆前中期低,而后期高.说明施铵态氮旗叶蔗糖合成能力强,源器官蔗糖向库运输迅速,籽粒库中糖源供应充足.因此,生产上可以通过改变氮素形态调节淀粉合成酶活性,进而调控淀粉的合成与积累.     

休闲期耕作对旱地小麦籽粒蛋白质形成及其相关酶活性的影响

为给旱地小麦高产优质栽培提供理论依据,通过大田试验研究了旱地小麦休闲期不同时间深翻、深松对0～300 cm土壤蓄水量、小麦籽粒蛋白质形成及其与氮代谢相关酶活性关系的影响.结果表明,休闲期深翻或深松均可提高旱地小麦播前0～300 cm土壤蓄水量,且欠水年效果明显,以前茬小麦收获后45 d深翻效果较好.休闲期耕作均显著提高了小麦蛋白质产量.耕作时间对籽粒蛋白质含量的影响因降雨年型不同而异,欠水年的休闲期耕作均显著降低了籽粒蛋白质含量;丰水年在麦收后15d耕作显著降低了籽粒蛋白质含量,而麦收后45 d耕作则显著提高了籽粒蛋白质含量,尤其显著提高了醇溶蛋白和麦谷蛋白含量,从而改善了品质.此外,丰水年麦收后45 d耕作可提高花后旗叶和籽粒谷氨酰胺合成酶(GS)活性、旗叶和籽粒谷氨酸合成酶(GOGAT)活性,降低花后旗叶和籽粒谷氨酸脱氢酶(GDH)活性;籽粒蛋白质的累积在麦收后15d耕作条件下与籽粒GDH活性关系密切,而麦收后45 d耕作条件下与旗叶GS和GOGAT活性相关性较大.总之,旱地小麦休闲期耕作在不同降雨年型下均可起到良好的蓄水保墒作用,且欠水年效果较明显;耕作时间对土壤水分、小麦氮代谢酶活性、籽粒蛋白质及其组分含量具有较大的调控效应,休闲期雨后耕作有利于籽粒蛋白质形成,且深翻效果较好.     

不同形态氮素对弱筋小麦籽粒淀粉积累及其相关酶活性的影响

为给弱筋小麦优质高产高效栽培的合理氮肥运筹提供理论依据,在大田条件下研究了3种形态的氮素（酰胺态氮、铵态氮和硝态氮）对弱筋小麦豫麦50籽粒淀粉合成及其相关酶活性的影响。结果表明,施铵态氮能增加灌浆中后期籽粒总淀粉和支链淀粉积累量,保持较高的籽粒总淀粉和支链淀粉积累速率,而施酰胺态氮籽粒直链淀粉积累量和积累速率较高。施铵态氮有利于提高成熟期籽粒总淀粉、支链淀粉含量和支／直比例,而施酰胺态氮提高了直链淀粉含量。施硝态氮对小麦籽粒淀粉积累的调控效应介于施铵态氮和施酰胺态氮之间。施铵态氮和施硝态氮后旗叶蔗糖合成酶（SS）和灌浆中后期蔗糖磷酸合成酶（SPS）活性高,灌浆中后期籽粒蔗糖合成酶（SS）活性、籽粒蔗糖含量、可溶性淀粉合成酶（SSS）活性高,束缚态淀粉合成酶（GBSS）活性低,而施酰胺态氮则表现出相反的趋势。施硝态氮的旗叶蔗糖含量始终最低;与施酰胺态氮相比,施铵态氮旗叶蔗糖含量灌浆前中期低,而后期高。说明施铵态氮旗叶蔗糖合成能力强,源器官蔗糖向库运输迅速,籽粒库中糖源供应充足。因此,生产上可以通过改变氮素形态调节淀粉合成酶活性,进而调控淀粉的合成与积累。     

Comparative metabolic profiling of pigmented rice (Oryza sativa L.) cultivars reveals primary metabolites are correlated with secondary metabolites

Gas-chromatography coupled with time-of-flight mass spectrometry (GC-TOFMS) was used to analyze the relationships between primary metabolites and phenolic acids in rice (Oryza sativa L.), including six black cultivars and one white cultivar. A total of 52 metabolites were identified, including 45 primary metabolites and seven phenolic acids from rice seeds. The metabolite profiles were subjected to data mining processes, including principal component analysis (PCA), Pearson's correlation analysis, and hierarchical clustering analysis (HCA). PCA could fully distinguish between these cultivars. HCA of these metabolites resulted in clusters derived from common or closely related biochemical pathways. There was a positive relationship between all phenolic and shikimic acids. Projection to latent structure using partial least squares (PLS) was applied to predict the total phenolic content based on primary metabolite profiles from rice grain. The predictive model showed good fit and predictability. The GC-TOFMS-based metabolic profiling approach could be used as an alternative method to predict food quality and identify metabolic links in complex biological systems.     

Volatile metabolite profiling of malt contaminated by Fusarium poae during malting

A volatile metabolite-profiling approach based on solid-phase microextraction (SPME) combined with gas chromatography–mass spectrometry was used to investigate volatile metabolic changes over the course of a malting process contaminated by Fusarium poae to assess its influence on malt flavor. GC–MS analysis of time-serial samples revealed a broad spectrum of volatile compounds including aldehydes, ketones, alcohols, organic acids, aromatics and furans. Statistical assessment of the data via principal component analysis demonstrated that at the initial phase of germination, the influence of F. poae was relatively small. However, its influence increased over time, resulting in differences between contaminated and controlled samples at 120 h and 144 h. Analysis of the corresponding loadings showed that volatile metabolites from green malt were influenced by contamination with F. poae fungi during malting to an extent, especially for the volatile aldehyde fractions. These compounds can be formed during both primary and secondary metabolism, and the potential exists for metabolic perturbation resulting from F. poae.     

Amycolachromones A–F,Isolated from a Streptomycin-Resistant Strain of the Deep-Sea Marine Actinomycete Amycolatopsis sp. WP1

In this study, a detailed chemical investigation of a streptomycin-resistant strain of the deep-sea marine, actinomycete Amycolatopsis sp. WP1, yielded six novel amycolachromones A–F (1–6), together with five known analogues (7–11). Amycolachromones A–B (1–2) possessed unique dimer skeletons. The structures and relative configurations of compounds 1–11 were elucidated by extensive spectroscopic data analyses combined with X-ray crystal diffraction analysis. Plausible biogenetic pathways of amycolachromones A–F were also proposed.     

酸碱条件对枯草芽胞杆菌FJAT-14254代谢物产生的影响

为考察酸碱条件对枯草芽胞杆菌FJAT-14254代谢物产生的影响,采用气相色谱-质谱联用分析枯草芽胞杆菌FJAT-14254菌株的胞内成分。结果表明：通过谱库扫描得到32种高匹配率代谢物的初步鉴定结果,主要包括氨基酸类、酸类、烷烃类等,其中含量相对较高的有7种;枯草芽胞杆菌FJAT-14254代谢物的种类和含量与其培养环境的酸碱度变化呈一定的相关性,强酸性(pH＝3)条件下培养的胞内代谢物具有特异性,而接近中性(pH＝5、7)条件及碱性(pH＝9、11)条件下培养胞内代谢物则相似。由此推断,不同pH条件影     

Secondary Metabolites from Marine Sponges of the Genus Oceanapia: Chemistry and Biological Activities

In this review, we summarized the distribution of the chemically investigated Oceanapia sponges, including the isolation and biological activities of their secondary metabolites, covering the literature from the first report in 1989 to July 2019. There have been 110 compounds reported during this period, including 59 alkaloids, 33 lipids, 14 sterols and 4 miscellaneous compounds. Besides their unique structures, they exhibited promising bioactivities ranging from insecticidal to antibacterial. Their complex structural characteristics and diverse biological properties have attracted a great deal of attention from chemists and pharmaceuticals seeking to perform their applications in the treatment of disease.     

2株高产蛋白微藻细胞代谢物的比较

以2株新近分离出来的链带藻(Desmodesmus sp. QL96和Desmodesmus sp. QJ74)为研究对象,检测胞内主要细胞代谢产物组成及含量变化,找出优势细胞代谢产物。收集相同时间间隔下培养的2株微藻,经过冻干、研磨、复溶,制备成细胞溶解液,再进行逐级萃取,分级检测每个萃取步骤中所得细胞代谢产物的含量。结果表明:在BG11培养基中生长30 d,链带藻Desmodesmus sp. QL96和Desmodesmus sp. QJ74的最高蛋白含量分别达到细胞干重的71.68%和62.14%,其他代谢产物,如碳水化合物、脂质和色素,在2株微藻中的含量都没有超过20%。对比其他微藻的文献报道,链带藻Desmodesmus sp. QL96是目前发现的蛋白含量最高的藻株,其蛋白的表达模式和蛋白相关产品的开发具有研究价值。     

Chemical Diversity and Biological Activity of Secondary Metabolites from Soft Coral Genus Sinularia since 2013

Sinularia is one of the conspicuous soft coral species widely distributed in the world’s oceans at a depth of about 12 m. Secondary metabolites from the genus Sinularia show great chemical diversity. More than 700 secondary metabolites have been reported to date, including terpenoids, norterpenoids, steroids/steroidal glycosides, and other types. They showed a broad range of potent biological activities. There were detailed reviews on the terpenoids from Sinularia in 2013, and now, it still plays a vital role in the innovation of lead compounds for drug development. The structures, names, and pharmacological activities of compounds isolated from the genus Sinularia from 2013 to March 2021 are summarized in this review.     

Bioactive Terpenes from Marine-Derived Fungi

Marine-derived fungi continue to be a prolific source of secondary metabolites showing diverse bioactivities. Terpenoids from marine-derived fungi exhibit wide structural diversity including numerous compounds with pronounced biological activities. In this review, we survey the last five years’ reports on terpenoidal metabolites from marine-derived fungi with particular attention on those showing marked biological activities.     

Physiological and proteomic analyses provide insights into the rice yellowing

Integrated physiological and proteomic analyses using japonica rice and glutinous rice were applied to investigate the proteome regulation related to rice yellowing during natural storage. The changes of soluble sugar and soluble protein combined with the up-regulation expression of related proteins indicated the enhancement of carbohydrate, protein and lipid metabolism in yellowed rice. The expression of heat shock protein was up-regulated, indicating that rice yellowing occurred under heat, dry or other abiotic stress. Nevertheless, this study noted that the rice yellowing might be associated with the emergence of secondary metabolites, because the gene ontology analysis showed that the biosyntheses of secondary metabolites and phenylpropanoid were significantly enriched in yellowed rice. Based on above results, a possible proteome regulation of rice yellowing is proposed in the current study.     

New Diterpenoids and Isocoumarin Derivatives from the Mangrove-Derived Fungus Hypoxylon sp.

Two new diterpenoids, hypoxyterpoids A (1) and B (2), and four new isocoumarin derivatives, hypoxymarins A–D (4–7), together, with seven known metabolites (3 and 8–13) were obtained from the crude extract of the mangrove-derived fungus Hypoxylon sp. The structures of the new compounds were elucidated on the basis of 1- and 2-dimensional (1D/2D) nuclear magnetic resonance (NMR) spectroscopic and mass spectrometric analysis. The absolute configurations of compounds 1, 2, 4, 5, and 7 were determined by comparison of experimental and calculated electronic circular dichroism (ECD) spectra, and the absolute configurations of C-4′ in 6 and C-9 in 7 were determined by [Rh₂(OCOCF₃)₄]-induced ECD spectra. Compound 1 showed moderate α-glucosidase inhibitory activities with IC₅₀ values of 741.5 ± 2.83 μM. Compounds 6 and 11 exhibited DPPH scavenging activities with IC₅₀ values of 15.36 ± 0.24 and 3.69 ± 0.07 μM, respectively.