Postharvest Application of 1-Methylcyclopropene Maintains Quality and Extends the Shelf-Life of Zizania latifolia during Storage at 25˚C

The effects of 1-methylcyclopropene (1-MCP) on postharvest quality of Zizania latifolia during storage at 25˚C were investigated. The results pointed out that a postharvest application of 1-MCP maintained the good visual appearance of fresh Z. latifolia, inhibited browning, mildew and weight loss at the bottom of Z. latifolia, and there is no significant changes on L, a*, b* and ΔE during the whole storage period. In addition, 1-MCP treatment inhibited the respiratory intensity of Z. latifolia during the first three days of storage, but it was significantly higher than that of the control on the sixth day of storage. Compared with the control, 1-MCP treatment maintained relatively high SOD, CAT, APX activities and low PAL, POD, PLD, lipase and LOX activities, delayed the decline of AsA content, reduced the accumulation of O2-, H2O2 and MDA, and ultimately maintained the integrity of cell structure and delayed the senescence of Z. latifolia. In addition, positive effects of 1-MCP on maintaining the cell structure integrity were observed in this investigation throughout the storage period at 25˚C.

Isolation of Zizania latifolia Species-specific DNA Sequences and Their Utility in Identification of Z. latifolia DNA Introgressed into Rice

根据两个植物抗病基因N和RPS2中核酸结合位点 (NBS)和富亮氨酸重复区 (LRR)中的保守序列设计了一对特异引物 ,用PCR从具有水稻 (OryzasativaL .)改良所需要的许多优良性状的水稻近缘野生种菰 (Zizanialatifolia(Griseb .)Turcz.exStapf)的基因组DNA中扩增同源片段。PCR产物经克隆后 ,分别以菰和水稻的基因组DNA为探针 ,通过点杂交对所得克隆进行了分析。点杂交结果表明 ,在所分析的 6 0个克隆中有 2个克隆是菰专化的序列 ,即它们与水稻无杂交信号。基因组DNA的Southern杂交进一步证实了这 2个克隆的专化性。为了验证一些可能的“水稻_菰”渐渗杂交系是否确实含有源自供体菰的DNA ,以这 2个克隆为探针 ,与经EcoRⅠ酶切的 5个可能的渐渗杂交系进行了Southern杂交。结果表明 ,这 2个克隆均能检测出其中的一个系含有其同源序列。这一结果为曾经报道的经一种非常规有性杂交方法将菰DNA导入水稻提供了确凿的证据。

Research on Purification Effect of Jian Lake Zizania latifolia Wetland Lakefront Zone in Northwest of Yunnan Plateau on Nitrogen and Phosphorus of Agricultural Non-point Source

As the main external pollution source of lake,nitrogen and phosphorus from agricultural non-point source make a great contribution to the lake eutrophication pollution.Wetland lakefront zone which plays a key role in externally agricultural non-point source pollution is considered as the biggest barrier for controlling external pollution.In this research,the Jian lake plateau Zizania latifolia wetland lakefront zone was selected for agricultural non-point source pollutions control with the systematic field research,and the lakefront zone was approved to have an effective purification effect on nitrogen and phosphorus from Jinlong River; the theoretical mechanism of lakefront zone removing nutrient was also investigated.Z.latifolia wetland lakefront zone could remove nitrogen and phosphorus from Jinlong River and the removal ratio can reach 55.8-62.52% and 59.47-69.81% respectively.So,we can indicate that the Jian Lake plateau Z.latifolia wetland lakefront zone had a good effect on controlling agricultural non-point source pollution and protecting the environment.

菰(Zizania latifolia)ISSR反应体系的建立及优化

菰是一种稻族野生资源,水生或沼生,在我国有着广泛的分布。野生菰群体不仅是一种重要的育种基因资源,同时还有着巨大的生态作用。为建立适宜于菰的ISSR反应体系,以菰DNA基因组为模板对ISSR反应体系中的主要影响因子进行优化。采用单因素变量法在12个不同梯度水平上设计正交试验针对体系中d NTPs浓度、Mg2+浓度、Taq聚合酶浓度、引物浓度、模板DNA浓度及引物退火温度等6个因子进行优化,确定了在20μL ISSR反应体系中各组分的最适因素水平分别为:3.0 mmol Mg2+(10×Buffer),0.5 mmol d NTPs、1.0μmol引物浓度、0.24 U/μL Taq聚合酶、1.5 ng/μL DNA模板以及55℃退火温度。应用该优化体系对80个菰材料进行扩增,证实了该体系的适用性和稳定性,为菰遗传资源的鉴定、评价与利用提供了技术支撑。

菰(Zizania latifolia)主要农艺性状及其驯化育种

通过收集我国菰野生资源和半野生资源并进行驯化育种,获得了株型紧凑、茎叶粗壮直立的2个半驯化菰材料"加油1号"和"戈山1号",并以该半驯化菰为育种材料,对它们的染色体基数、花期、花序结构、种子性状及发芽率等进行研究.结果表明:中国菰(Zizania latifolia)染色体数为2n=34条,不同于北美菰;"加油1号"的花期主要在9月中旬到10月中旬之间,总体比野生菰早约15d,比"戈山1号"晚约10d;在菰花序中雌雄花比例约为1∶1.8,并首次绘制了其花序模式图;"加油1号"菰糙米千粒质量为12.7g,粒长和宽分别为9.70mm和1.48mm,比北美沼生菰(Z.palustris)偏小;电镜观察发现菰米淀粉粒排列规则;采用改良的种子处理方法,菰种发芽率可以达到62.9%.本研究获得的半驯化菰材料开花正常,株型紧凑,为实现中国菰驯化提供了重要的基础遗传材料,但在落粒性和花期等目标农艺性状上还有待改良.

茭草(Zizania latifolia)在不同人工湿地中的生长适应性

茭草是太湖流域河、湖水陆交错带及低洼沼泽中普遍生长的挺水植物,其生长条件在当地挺水植物中具有代表性.根据该流域河道水陆交错带的现状与挺水植物生长特性,针对性地设计了置入式生态滤床、生物氧化池、潜流表面流复合人工湿地和水平潜流人工湿地4种不同生境条件,研究茭草的生长适应性,为建立与恢复退化的河道水陆交错带植被群落提供科学依据和技术支持.结果表明,茭草能够适应不同生长环境,在沸石基质和水培环境中均能正常生长;不同环境条件下其生长速度和繁茂程度存在差异.

Transgenic Rice Plants Harboring Genomic DNA from Zizania latifolia Confer Bacterial Blight Resistance

Based on the sequence of a resistance gene analog FZ14 derived from Zizania latifolia （Griseb.）, a pair of specific PCR primers FZ14P1/FZ14P2was designed to isolate candidate disease resistance gene. The pooled-PCR approach was adopted using the primer pair to screen a genomic transformation-competent artificial chromosome （TAC） library derived from Z. latifolia. A positive TAC clone （ZR1） was obtained and confirmed by sequence analysis. The results indicated that ZR1 consisted of conserved motifs similar to P-loop （kinase la）, kinase 2, kinase 3a and GLPL （Gly-Leu-Pro-Leu）, suggesting that it could be a portion of NBS-LRR type of resistance gene. Using Agrobacterium-mediated transformation of Nipponbare mature embryo, a total of 48 independent transgenic To plants were obtained. Among them, 36 plants were highly resistant to the virulent bacterial blight strain PXO71. The results indicate that ZR1 contains at least one functional bacterial blight resistance gene.

Effects of Fenaminosulf on Yield and Benefit of Single Cropping Zizania latifolia

[Objective]The paper was to normalize the application of fenaminosulf in single cropping Zizania latifolia. [Method]Effects of spraying periods,different concentrations and spraying times of fenaminosulf on yield and output value of single cropping Z. latifolia were studied.[Result]In some regions where single cropping Z. latifolia could be harvested twice per year,fenaminosulf significantly promoted formation of swollen gall,and advanced the harvest period for about 50 d. Application of 0.5 g/L（ a.i.） fenaminosulf at 150,160 and 175 d post transplanting promoted swollen gall formation and enhanced the yield of Z. latifolia.In normal single cropping Z. latifolia growing regions,once application of fenaminosulf obviously advanced harvest period and improved yield and benefit of Z. latifolia,but with the increasing frequency of use,yield and benefit of Z. latifolia decreased significantly.[Conclusion]It is recommended that 1.0 g/L（a.i.） fenaminosulf can be applied for just once at 40-60 d post transplanting of Z. latifolia.

Isolation,identification and artificial inoculation of Ustilago esculenta on Zizania latifolia

The smut Ustilago esculenta is an endophytic fungus that invades Zizania latifolia(Jiaobai)and plays an important role in inducing the host stem to form a swollen gall.The aims of this study were to investigate isolation,identification and inoculation methods of U.esculenta from Jiaobai.The spore suspension culturing method was the best method of isolating U.esculenta,and yeast-like fungal strains and septate hyphal strains were obtained.The universal primers ITS1 and ITS4 amplified a ribosomal DNA spacer element from all tested strains,while specific primers for Lam16A gene generated a 442 bp product only with septate hyphae strains.De novo transcriptome assembly results showed that the yeast-like fungal strains did not match Ustilago,and genomic analysis suggested the septate hyphae strains were highly similar to known smut fungi.Therefore,the septate hyphae strains were identified as U.esculenta,which indicated that the ITS primers were not species-specific but that Lam16A-specific primers can distinguish U.esculenta accurately and easily.In vitro,U.esculenta grew quickly on PDA medium at 28°C in darkness.Furthermore,an inoculation method was established to produce swollen stems by injecting a spore suspension of U.esculenta at OD600=2.5 into the basal culm internode of male Jiaobai.

斧头湖挺水植被的群落学研究——Ⅰ.菰群落(Com.Zizania latifolia)的结构

本文从物种结构、水平结构和垂直结构三个方面结合其时间特征对湖北省武昌县斧头湖的菰群落进行了分析。结果表明:①菰群落的区系组成和生长型较为丰富,菰是该群落中唯一的建群种;②菰群落内部表现出不同物种的种群分布在水平方向上的分化。菰群落内部小环境多样,存在着许多小群落。菰的抽条为群聚分布,表现出形态学格局;③菰群落垂直结构简单,多数情况下仅存在一个挺水植被层。群落生产结构的变化与水位及其本身的生长特性有关。菰群落的地下成层现象也是一个值得注意的问题。

不同时期菰(Zizania latifolia)幼苗对短期淹没的形态学响应

菰(Zizania latifolia)是长江中下游流域常见的挺水植物.为了解菰在野外的扩张和退化机制,本研究通过模拟实验分析了不同时期菰幼苗对短期淹没的形态学响应.实验共选择株高36和70 cm两种幼苗,设计不淹没、50%淹没和100%淹没3个处理.研究结果表明:两组菰幼苗地上部分的形态学响应有一定差异.在100%淹没处理下,36 cm幼苗组株高最低,茎粗和最大叶宽均显著低于其他两个处理;而70 cm幼苗组在不淹没处理下株高最低,茎粗和最大叶宽在50%和100%淹没处理下均无显著差异.两组菰幼苗根系的形态学响应也不一致.36 cm幼苗组,100%淹没处理组的所有6个根系指标均与其他两种处理有显著差异;70 cm幼苗组,不淹没处理组的6个根系指标均与其他两种处理有显著差异.随着淹没深度的增加,两组菰幼苗总生物量和根茎比均逐渐下降;但36 cm幼苗组在100%淹没处理下总生物量和根茎比均显著低于其他两个处理,而70 cm幼苗组在50%和100%淹没处理下却无显著差异.综合以上分析,本研究结果表明随着菰幼苗的生长,其对淹没的形态学响应能力增强.本研究结果对长江中下游湖泊菰的生态调控具有重要意义.

菰（Zizania latifolia）研究及利用概况

从菰的系统发生与分布、植物学特性、菰的研究概况、菰的开发利用等方面来阐述菰研究及其利用概况,并对今后的研究进行了展望。

Shoot rot of Zizania latifolia and the first record of its pathogen Pantoea ananatis in China

The aquatic grass Zizania latifolia grows symbiotically with the fungus Ustilago esculenta producing swollen structures called Jiaobai,widely cultivated in China.A new disease of Z.latifolia was found in Zhejiang Province,China.Initial lesions appeared on the leaf sheaths or sometimes on the leaves near the leaf sheaths.The lesions extended along the axis of the leaf shoots and formed long brown to dark brown streaks from the leaf sheath to the leaf,causing sheath rot and death of entire leaves on young plants.The pathogen was isolated and identified as the bacterium Pantoea ananatis,based on 16 S ribosomal RNA(r RNA)gene sequencing,multilocus sequence analysis(atp D(β-subunit of ATP synthase F1),gyr B(DNA gyrase subunit B),inf B(translation initiation factor 2),and rpo B(β-subunit of RNA polymerase)genes),and pathogenicity tests.Ultrastructural observations using scanning electron microscopy revealed that the bacterial cells colonized the vascular tissues in leaf sheaths,forming biofilms on the inner surface of vessel walls,and extended between vessel elements via the perforated plates.To achieve efficient detection and diagnosis of P.ananatis,species-specific primer pairs were designed and validated by testing closely related and unrelated species and diseased tissues of Z.latifolia.This is the first report of bacterial sheath rot disease of Z.latifolia caused by P.ananatis in China.

Transcriptomics and metabolomics reveal the possible mechanism by which 1-methylcyclopropene regulates the postharvest senescence of Zizania latifolia

To understand the mechanism governing the postharvest senescence of Zizania latifolia(Z.latifolia),and the regulatory mechanism induced by 1-methylcyclopropene(1-MCP)during storage at 25℃,physiobiochemical and conjoint analyses of the transcriptome and metabolome were performed.The results indicated that 1-MCP treatment engendered changes in the expression of genes and metabolites during the postharvest storage of Z.latifolia.The 1-MCP treatment maintained a good visual appearance,preserved the cell structure and membrane integrity of Z.latifolia by keeping the expression of membrane-related lipolytic enzymes(and related genes)low and the amount of phosphatidylethanolamine high.Compared to the control group,1-MCP treatment enhanced the activities of antioxidant enzymes,resulting in a decrease of reactive oxygen species and malondialdehyde contents,and thus inhibition of oxidative damage and loss of membrane integrity.In addition,1-MCP treatment retarded the senescence of Z.latifolia by downregulating the expression of ethylene biosynthesis-related genes and promoting upregulation of brassinosteroid insensitive 1 kinase inhibitor 1,calmodulin,glutathione reductase,jasmonate amino acid synthase,and mitogen-activated protein kinase-related genes.Moreover,1-MCP retarded Z.latifolia senescence by inducing the activity of adenosine triphosphate(ATP)biosynthesis-related genes and metabolites.Our findings should facilitate future research on the postharvest storage of Z.latifolia,and could help delay senescence and prolong the storage time for commercial applications.

茭虾共作对土壤氮磷含量和茭白干物质积累及氮磷钾吸收分配的影响

为探究茭白种养模式的施肥策略,设置茭虾共作(ZC)、茭白单作(Z)2个处理,研究茭虾共作对土壤氮磷含量、茭白产量和茭白干物质积累及氮磷钾吸收分配的影响。2021-2022年的研究结果显示,茭虾共作模式较茭白单作模式采茭期土壤中全氮、全磷、速效磷的含量分别提高了10.85%~38.89%、5.45%~13.79%、6.19%~61.79%,净茭产量提高了5.10%~19.54%,采茭期茭白茎、叶、净茭的干物质积累量分别增加14.41%~16.58%、10.28%~15.15%、10.57%~21.45%。2021年茭虾共作处理较茭白单作处理在采茭期叶的氮含量显著增加了25.74%,但在孕茭期茎中磷含量显著减少了16.76%;2022年氮肥减量、减量投喂下,茭虾共作处理较茭白单作处理在孕茭期茎的氮含量显著减少了23.75%,在分蘖期叶中磷含量显著减少了12.08%,2a全生育期同一器官的钾含量在2个处理间差异不显著。对于养分积累,2021年茭虾共作处理在分蘖期叶的氮、磷、钾积累量较茭白单作处理分别减少26.04%、27.27%、30.11%,但在采茭期茎的氮、钾积累量和叶的氮、磷积累量较茭白单作处理分别增加18.80%、38.41%和44.77%、35.71%;2022年在氮肥减量、饲料减量投喂下,茭虾共作处理在采茭期叶的磷积累量和茎的钾积累量较茭白单作处理显著增加30.0%和30.77%。关于养分分配,2种处理的茭白在孕茭期和采茭期氮素的分配均以茎、叶为主,而磷、钾元素的分配均以茎为主,茎分配比例在42%~66%。对于养分转运,2021年2种处理茭白的根、茎、叶在氮、磷转运上大多为表现为“库”器官,而在钾转运上大多表现为“源”器官;2022年氮肥减量、减量投喂下,茭白的根、茎、叶在氮、磷、钾转运量上大多表现为“源”器官。因此,在茭虾共作模式中适当减少肥料、饲料的投入,能促进形成合理的源库关系,有利于茭白产量的形成。

响应面法优化茭白多糖硫酸化工艺及其抗氧化活性分析

为提高茭白多糖抗氧化活性,对茭白多糖进行硫酸化修饰,并探索其最佳修饰条件。以茭白为原料,利用水提醇沉法提取并纯化一种新型水溶性多糖,采用三氧化硫-吡啶法,以甲酰胺为溶剂,对多糖进行硫酸改性,以硫酸根取代度(DS)为指标,利用响应面法对茭白多糖进行硫酸改性条件优化,同时通过体外自由基清除率实验对比改性前后体外抗氧化活性。结果表明:采用响应面法辅助茭白多糖硫酸化修饰条件优化得到最佳反应条件为多糖样品100 mg,酯化时间4 h,酯化温度70℃,三氧化硫-吡啶复合物添加量2.6 g,得到最佳DS为1.79;热重分析显示茭白多糖在46.38℃时失重最快,失重率为16.48%;硫酸化茭白多糖在65.04℃时失重最快,失重率为2.92%。在体外抗氧化实验中,茭白多糖对于DPPH·、·OH以及ABTS^(+)·清除能力的IC_(50)值分别为3.49、3.28和12.70 mg/mL;硫酸化茭白多糖为0.39、1.00和1.82 mg/mL;阳性对照(V_(C))为0.069、0.17和0.077 mg/mL。综上表明,硫酸化修饰能提高茭白多糖的热稳定性;同时一定程度上增强其自由基清除能力。

我国中部水网区茭白潜流湿地进出水质和净化性能时变特征

本研究从小集水区角度研究了茭白潜流湿地进出水氮、磷、COD_(Cr)污染和净化性能的时变特征,结果表明,茭白潜流湿地进水氮、磷、COD_(Cr)季节波动大,其中春节期间湿地进水总氮(TN)和总磷(TP)最高,其次是农田施用化肥后产生地表径流的首月,中等降雨量下湿地进水COD_(Cr)浓度高于强暴雨下的浓度。受沉淀池的调节缓冲,湿地进水氨氮(NH_(3)-N)和硝态氮(NO_(x)^(-)-N)秋季最高,其次是春节后。湿地对小集水区氮、磷、COD_(Cr)冲击负荷均具有良好的缓冲能力和净化性能,TP、TN和COD_(Cr)平均去除率分别为(82.1±10.5)%、(72.9±8.1)%和(65.6±6.2)%;秋冬季过渡期间,因微生物降解和基质吸附的协同作用使得植物吸收氮磷的季节拐点不明显;冬季湿地具有耐受中部水网区低温的能力。不过冬季低温易于引起潜流湿地内有机氮分解转变为NH_(3)-N后被沸石等基质吸附而发生积聚,同时较长水力停留时间(HRT)下因有机质分解耗氧引起环境厌氧的加剧。此外,冬季出水溶解有机磷(DOP)比例增加。该潜流湿地可有效提升村镇面源污染排水水质,改善乡村水环境,但对上述受季节影响较大的时变因素应加强管控。

不同茭白品种福寿螺卵块分布及竹片诱螺产卵效果

为了研究控制茭白田福寿螺种群的方法,本文在调查不同茭白品种上福寿螺卵块分布差异基础上,开展不同规格(3、6、9 cm宽)竹片诱集福寿螺产卵试验。结果显示,不同茭白品种上福寿螺卵块分布数量差异大,单季茭白品种以‘杭州一点红’上卵块最多(11.6个/丛),远高于其他9个品种,最少的是‘八月茭’‘金茭1号’(分别为1.7、2.3个/丛)。双季茭白品种间的差异不显著,每个茭白品种上的卵块数在5.1~7.4个之间。不同规格竹片对福寿螺的产卵诱集效果差异大,引诱效果最好的为9 cm规格的竹片效果最差的是3 cm规格竹片。竹片凸面诱集到的卵块较多,凹面诱集到的卵块很少,竹片凸面朝田埂方向插入诱集产卵效果更好。福寿螺的产卵高度呈正态分布,主要集中在20~40 cm之间,未发现有靠近水面或在水下的卵块,卵块大小与数量呈线性正相关。研究结果为利用竹片诱集茭白田福寿螺产卵提供了技术依据。

茭白秆水解制备高价值呋喃平台化合物研究

生物质转化为高价值呋喃平台化合物是生物质资源利用的重要方式。以工业副产物偏钛酸作为固体酸催化剂,将茭白秆转化为5-羟甲基糠醛(HMF)和糠醛,研究物理活化、溶剂体系等对茭白秆水解性能的影响,并优化反应工艺条件。结果表明,茭白秆具有更低的木质素含量和纤维素晶型结构,比茭白叶更容易被物理活化。在200℃、30 min的反应条件下,球磨活化的茭白秆获得了最高的HMF和糠醛收率,分别为11.66%和7.30%。反应动力学分析表明,偏钛酸催化球磨茭白秆转化的活化能低,相较于文献报道的其他木质纤维素生物质,球磨茭白秆的高值化转化具有优势。

茭白WRKY基因家族鉴定及菰黑粉菌侵染下的表达分析

WRKY基因家族是植物最大的转录因子家族之一,在植物生长发育及逆境胁迫响应过程中起重要调控作用。基于茭白基因组数据库,鉴定WRKY基因家族并对其进行生物信息学分析,同时研究菰黑粉菌侵染下ZlWRKYs的表达模式。结果表明,茭白基因组中共鉴定出120个ZlWRKY家族基因,命名为ZlWRKY1~ZlWRKY120,分布在17条染色体上。ZlWRKYs可分为Ⅰ、Ⅱ和Ⅲ类,其中Ⅰ类有17个ZlWRKYs,Ⅱ类有72个ZlWRKYs,Ⅲ类有31个ZlWRKYs。茭白ZlWRKYs成员在进化上存在基因片段复制;启动子顺式作用元件分析表明,ZlWRKYs包含多个与激素、逆境胁迫响应和生长发育相关的元件。菰黑粉菌侵染3 h,大部分ZlWRKYs基因呈现上调表达,其中ZlWRKY33相对表达量最高。本研究为深入探讨茭白ZlWRKYs基因功能以及解析雄茭响应菰黑粉菌侵染的分子机制提供理论基础。