半干旱黄土丘陵沟壑区柳枝稷(Panicum virgatum)的生物质形成

为深入认识半干旱黄土丘陵沟壑区引种能源植物柳枝稷生物质生产的开发潜力及其约束机制,调查了农田、植丛尺度上早熟和晚熟柳枝稷年度生命周期内生物量累积、分株建成动态,以及土壤水分供求平衡过程。研究发现,植丛尺度早熟柳枝稷抽穗比例近100%,分株生殖发生大小阈值依赖基本丧失,高度大小分布近似正态,种群内光资源竞争强度明显弱化,与晚熟类型形成明显差异。农田尺度晚熟柳枝稷生物质产量可以达到15t/hm2,高出早熟类型近1倍,但是其立地80～400cm土层的含水量稳定在7%以下,土壤干旱已经发生,早期干旱胁迫导致的生长停滞,以及生长中后期的成片倒伏现象在两年的观测周期内连续出现。早熟柳枝稷立地则形成相对稳定的白草、柳枝稷复合优势植被结构,深层土壤水分含量稳定在10%以上,实现了跨年度的土壤水分供求平衡。植丛尺度的生物质形成在一定程度上取决于分株生殖发生的大小依赖程度和分株间竞争关系格局,基于植丛尺度普遍的生殖发生和明显弱化的光资源竞争,早熟柳枝稷表现出更为高效的生物质形成机制。农田尺度晚熟柳枝稷尽管在雨热同步期的降水资源利用效率上存在明显比较优势,但是在降水资源利用分配策略和效应上,早熟柳枝稷表现出了综合的生态适宜性优势。保证雨热同步期降水资源利用和保蓄的平衡,是半干旱黄土丘陵沟壑区生物质生产应该遵循的基本原则之一。

Phytoextraction of Trace Metals (Cd, Ni and Pb) by Panicum maximum Grown on Natural Soil

This study aims to assess the effective capacity of Panicum maximum to accumulate cadmium (Cd), nickel (Ni) and lead (Pb). P. maximum observed in a greenhouse was subjected to 2 ppm of Cd, 50 ppm of Ni, 100 ppm of Pb contaminated soil and uncontaminated soil, for 120 days. Plant growth and biomass produced concentration of trace metals in soil and plant, bioaccumulation and transfer factors, location of potentially toxic elements in tissues and cells of plant have been determined. Stem length and biomass produced by P. maximum were higher on the uncontaminated soil followed respectively by those of soil-contaminated by Pb, Cd and Ni. Bioaccumulation factors of trace metals were 8.93 (Pb), 8.47 (Ni) and 3.37 (Cd). Ni was more accumulated in shoot biomass (FT > 1), while Pb and Cd were concentrated in root biomass (FT < 1). Pb is accumulated preferentially in endodermis (roots) and epidermis (leaves). As for Ni and Cd, they are concentrated in central cylinder of roots and in conductive bundles of leaves. At cellular level, Ni and Cd are mainly concentrated in intracellular compartments of leaves and roots, while Pb is strongly detected at cell walls.

Antimalarial and analgesic activities of ethanolic leaf extract of Panicum maximum

Objective:To evaluate antiplasmodial and analgesic activities of ethanolic leaf extract/ fractions of Panicum maximum.Methods:The crude leaf extract(47-190 mg/kg) and fractions (chlor of orm,ethyl acqeous and methanol;96 mg/kg) of Panicum maximum were investigated for antiplasmodial activity against chloroquine sensitive Plasmodium berghei infections in mice and for analgesic activity against chemical and heat-induced pains.The antiplasmodial activity during early and established infections as well as prophylactic were investigated.Artesunate at 5 mg/kg and pyrimethamine at 1.2 mg/kg were used as positive controls.Analgesic activity of the crude extract/fractions was also evaluated against acetic acid,formalin and heat-induced pains.Results:The extract and its fractions dose-dependently reduced parasitaemia induced by chloroquine sensitive Plasmodium berghei infection in prophylactic,suppressive and curative models in mice.These reductions were statistically significant(P【0.001).They also improved the mean survival time from 13 to 28 days compared with control(P【0.001).The activities of extract/ fractions were incomparable to that of the standard drugs(Artesunate and pyrimethamine).On chemically and thermally-induced pains.the extract inhibited acetic acid and formalin-induced inflammation as well as hot plate-induced pain in mice.These inhibitions were statistically significant(P【0.001) and in a dose-dependent fashion.Condusions:Panicum maximum leaf extract has antiplasmodial and analgesic activities which may in part be mediated through the chemical constituents of the plant.

Investigation on Agronomic Characters of Dwarf Mutant 778 in Broomcorn Millet(Panicum miliaceum L.)and Analysis of Its Sensitivity to GA

In order to investigate the differences between agronomic traits of dwarf mutant and original material 260 and whether the cause of dwarf is related to GA synthesis or signaling pathway,this experiment used dwarf mutant 778 and its original material 260 as experimental materials.Morphological observation and determination were performed for agronomic traits on plant height,ear length,internode length,internode number,seed length,seed width and number of seeds in different growth periods and different concentrations.The plants were treated by GA spraying,and the changes of plant height,root length,stem width,leaf length and leaf width were measured.The results are as follows:①The plant height of the dwarf mutant material was significantly different from that of the original high material,which was mainly caused by the difference between above-ground basal part and the length of the first and second elongation joints.②Comparing and analyzing the differences of traits between dwarf mutant material 778 and original high material 260,it was found that the plant height,ear length,internode number,grain number per ear and internode length of dwarf mutant 778 were significantly lower than that of high stalk 260(P<0.01),and the seed length of dwarf mutant 778 was significantly higher than that of high stalk 260(P<0.05).③Different concentrations of gibberellin(0,50,100,200 mg/L)had no significant effect on plant height and root length of dwarf mutant 778(P>0.05).Different concentrations of gibberellin had significant effects on plant height,root length and sensitivity coefficient of high stalk 260(P<0.05).And compared with the control group,all high materials 260 treated with different concentrations of gibberellin performed differently in plant morphology and growth potential.④Under the conditions of 100 and 200 mg/L GA,the difference of plant height between the dwarf mutant and the high stalk control decreased with time,and there was no difference at the end.There were no differences in sensitivity coefficient GRI between different concentrations of gibberellin treatment groups,indicating that the external gibberellin could restore the scorpion dwarf mutant to the original high stalk,and the gene that causes the mutation might be related with the gibberellin synthesis pathway.

Switchgrass (<i>Panicum virgatum</i>) Extract Mediated Green Synthesis of Silver Nanoparticles

A novel switchgrass (Panicum virgatum) extract mediated green process was demonstrated for the synthesis of silver nanoparticles from silver nitrate solution at ambient temperature. UV-visible spectroscopic analysis indicates the rapid reduction of silver (Ag+) ions by swithgrass extract. The silver nanoparticles began to form at 15 min and the reduction reaction was completed within 2 hours. Synthesized silver nanoparticles were subjected to x-ray diffraction (XRD) for structural characterization, which confirms the FCC symmetry of silver nanoparticles with the lattice parameter of 4.0962 ?. The particle size of bio-synthesized silver nanoparticles was identified through transmission electron microscopic (TEM) analysis and found to be in the range of 20 - 40 nm.

Influence of Lead and Cadmium Concentration on the Accumulation Capacity of Panicum maximum

The restoration of soils polluted by trace metals (Pb and Cd) by phytoremediation is an innovative and ecologically sustainable solution. The objective of the study was to develop a process of phytoaccumulation of trace metals (Pb and Cd) in soils with the species Panicum maximum. For this purpose, 30 buckets containing soil were used. These included six (06) buckets per dose of soil contamination by Pb and Cd (3 mg/kg and 9 mg/kg of Cd and 100 mg/kg and 300 mg/kg of Pb) and six (6) buckets containing uncontaminated soil (control). During a period of 90 days of experimentation, the concentrations of trace metals in the plant biomass and in the soils were measured. Also, the bioaccumulation (BF) and translocation (TF) factors, the mass of Pb and Cd taken up by the plant were determined. The results showed that the biomass produced was negatively influenced by increasing Pb and Cd concentration. The concentrations of Pb and Cd accumulated by P. maximum varied in the aboveground biomass from 6.48 ± 0.55 to 18.09 ± 0.71 mg/kg (Pb100);from 10.93 ± 0.38 to 23.04 ± 0.79 mg/kg (Pb300);from 0.91 ± 0.02 to 1.50 ± 0.03 mg/kg (Cd3);and from 3.05 ± 0.08 to 5.43 ± 0.09 mg/kg (Cd9) from day 30 to day 90. However, in the root biomass, trace metals (Pb and Cd) ranged from 8.09 ± 0.58 to 22.57 ± 0.86 mg/kg (Pb100);from 29.45 ± 0.49 to 62.35 ± 0.82 mg/kg (Pb300);from 0.66 ± 0.01 to 1.11 ± 0.07 mg/kg (Cd3);and from 2.22 ± 0.08 to 3, 97 ± 0.09 mg/kg (Cd9), from day 30 to day 90. Pb was concentrated in the root biomass and Cd in the aboveground biomass. Bioaccumulation factor values ranged from 0.26 ± 0.02 to 0.99 ± 0.04 (Pb100);from 0.21 ± 0.04 to 0.50 ± 0.06 (Pb300);from 0.83 ± 0.09 to 1.72 ± 0.18 (Cd3);and from 0.70 ± 0.08 to 1.54 ± 0.18 (Cd9). High concentrations of Pb and Cd show a negative effect on the accumulation potential of P. maximum.

不同光质对黍子(Panicum miliaceum)叶绿体光系统发育及psbA基因转录物稳态含量的影响

本文以一种C4植物——黍子(Panicum miliaceum)为材料,在白光、红光、蓝光、远红光和黑暗5种不同条件下培养黍子幼苗,叶片采收后用于叶绿素积累、叶绿体吸收光谱、叶绿体低温荧光发射光谱和高分子量cpRNA积累的测定以及psbA基因的Northern Blot分析。结果表明:白光、红光和蓝光下生长的黍子,它们的叶绿体都有功能完善的光合系统;而远红光下生长的黍子,已有光系统Ⅱ的发射峰,只是强度和波长都与白光、红光和蓝光下的有所不同;不同光质促进叶绿素积累和高分子量cpRNA积累的效率是平行的,其中红光较蓝光和远红光有效,而复合光(白光)的作用效果最好。当以白光诱导的积累量为100％时,可以分别求出不同光质诱导叶绿素积累和高分子量cpRNA积累的相对量,结果表明,高分子量cpRNA的积累对光的依赖性要比叶绿素积累对光的依赖性大得多。psbA基因的Northern Blot分析表明,不同光质下psbA转录物的积累与高分子量cpRNA的积累是一致的。据此我们推测,在黍子叶绿体的光诱导发育过程中,psbA的转录过程可能不受光信号的直接调控,而是受叶绿体整体发育状态的控制。

Molecular identification of plants regenerated from somatic hybridization between rice and apomictic Panicum

We attempted to introduce apomictic gene(s)into rice via somatic hybridization by usingapomictic Panicum maximum Jacq.as thedonor of apomictic gene(s).Protoplasts of rice derived from suspen-sion cells were inactivated with indoacetamide(IOA)and protoplasts of Panicum maximum

大黍(Panicum maximum Jacq.)的胚珠附器

观察了大黍(PanicummaximumJacq.)胚珠附器的发生时间、位置和发育过程及其细胞化学特征。结果显示:(1)大孢子母细胞时期,珠孔端有一个或多个珠心表皮细胞开始伸长、膨大,特化为胚珠附器。(2)当胚珠附器伸长、膨大至最大程度时,胚珠附器细胞表现出显著的极性特征:细胞核位于细胞的珠孔端,大而清晰;细胞内同时形成了一个特大的液泡,几乎占据了整个细胞的合点端;细胞质则被挤到珠孔端一侧,集中分布在核的周围。(3)胚珠附器从开始出现到发育成熟,都没有淀粉粒的积累;但是,PAS反应显示胚珠附器细胞壁和细胞质都比普通珠心细胞的染色程度深,这说明其细胞壁和细胞内部富含可溶性多糖。

Biological Characteristies of Methane Emission of Oryzasativa，Panicumcrus－galliand Cyperusdif for misGrown on PaddySoil

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冀东地区黍子(Panicum miliaceum L.)不同品系(种)农艺性状及产量比较

为了筛选出冀东地区适宜栽培的黍子(Panicum miliaceum L.)新品系,以晋黍8号为对照,对由河北省农林科学院提供的5个黍子高代新品系(JKS274,JKS711,JKS1025,JKS2143,JKS2869)的株型性状、穗部性状和产量等进行了对比试验。结果表明:5个黍子品系的产量、千粒质量、主穗粒质量存在较大差异,株高和主穗长差异较小。JKS2143的产量显著高于对照,较对照增产12.60%,其次为JKS2869,较对照增产1.94%,JKS1025和JKS711显著低于对照。JKS2143和JKS2869的千粒质量显著高于对照,JKS274和JKS1025与对照相比差异不显著,JKS711显著低于对照。主穗粒质量最突出的为JKS274,高于对照,但与对照差异不显著;其余4个品系均显著低于对照。黍子各性状与产量的相关性由高到低的排列顺序为:千粒质量,穗粒质量,主茎节数,分蘖数,主穗长,单株穗数,株高,成穗率。5个黍子高代品系中,JKS2143和JKS2869的综合性状较好,适宜在冀东地区栽培。

糜子GRF转录因子全基因组鉴定及在茎分生组织中的表达特征

为了解糜子(Panicum miliaceum L.)GRF(growth-regulating factor)基因家族成员全基因组信息及其在营养生长阶段分生组织中的表达特征,本研究通过生物信息学和转录组测序相结合的方法,分析了糜子GRF基因家族成员的染色体分布、基因结构、系统进化关系、顺式作用元件及其在营养器官茎分生组织中的表达特征。结果表明:糜子GRF基因家族包含21个成员,家族成员含有1~4个内含子和2~5个外显子,编码蛋白长度为224~618个氨基酸,等电点为4.93~9.69;PmGRF基因不均等分布于12条染色体上,除PmGRF13定位于细胞核和叶绿体外,其余均定位于细胞核。系统进化分析显示,糜子21个GRF基因分为4个亚族(A、B、C和D)。顺式作用元件分析表明,在糜子GRF基因上游2000 bp序列中,普遍存在数目不等、种类不同的参与光响应、激素响应、干旱诱导、低温和其他环境胁迫响应的顺式作用元件。对糜子高秆品种陇糜12号和矮秆品种张778拔节期节间和节部分生组织分别取样进行转录组测序及qRT-PCR分析,结果发现:PmGRF3、PmGRF12在矮秆品种张778中表达量显著高于高秆品种陇糜12号,而PmGRF4、PmGRF16和PmGRF21的表达特征与之相反;PmGRF2和PmGRF5在张778节间分生组织中的表达量显著高于陇糜12号,其余GRF基因不表达或差异表达不显著,表明PmGRF2、PmGRF3、PmGRF4、PmGRF5、PmGRF12、PmGRF16和PmGRF21等7个基因与糜子株高的形成相关。

东北春播区糜子核心种质的荧光微卫星标记鉴定

优异种质资源是糜子新品种选育和产业发展的基础。本研究以190份东北春播区糜子核心种质为材料,利用前期构建的SSR标记在5'端标注荧光,进行PCR扩增和毛细管电泳。根据毛细管电泳检测的片段有无采用“0/1”表示,利用ID Analysis4.0进行区分,使用PopGene、PowerMarker、MEGA、Structure、NTSYS进行遗传多样性分析。试验结果表明,3个荧光SSR标记组合(RYW3+RYW6+RYW28)可区分190份材料,共检测出等位变异73个,平均为24.3333;有效等位基因数(Ne)为5.4728(RYW3)~15.8922(RYW6),平均为9.6496;检出Shannon多样性指数(I)为2.0851(RYW3)~2.9457(RYW6),平均为2.4896;观测杂合度(Ho)为0.7529(RYW6)~0.9574(RYW28),平均为0.8876;期望观测杂合度(He)为0.8194(RYW3)~0.9398(RYW6),平均为0.8765;Nei’s基因多样性指数(Nei)为0.8173(RYW3)~0.9371(RYW6),平均为0.8741;多态性信息含量(PIC)为0.8656(RYW3)~0.9722(RYW6),平均为0.9198。基于UPGMA将190份资源划分为3个群组。基于Structure的遗传结构分析(K=3)将糜子核心种质分为3个类群,来源于东北地区的4个基因库(黑龙江、吉林、辽宁和内蒙古的一部分)。基于主成分分析将材料分为4个类群,与地理来源一致。利用在线二维码技术(https://cli.im/)构建了190份东北糜子核心种质的DNA分子身份证。

Assessment of genetic diversity in broomcorn millet (Panicum miliaceum L.) using SSR markers

The genetic diversity of 118 accessions of broomcom millet （Panicum miliaceum L.）, collected from various ecological areas, was analyzed. Using 46 SSR （Simple Sequence Repeat） polymorphic markers from rice, wheat, oat and barley, a total of 226 alleles were found, which exhibited moderate level of diversity. The number of alleles per primer ranged from two to nine, with an average of 4.91. The range of polymorphism information content （PIC） was 0.2844）.980 （average, 0.793）. The expected heterozygosity （He） varied from 0.346 to 0.989, with an average of 0.834. The average coefficient of the genetic similarity of SSR markers among the 118 accessions was 0.609, and it ranged from 0.461 to 0.851. The UPGMA （Unweight Pair Group Method with Arithmetic Mean） clustering analysis at the genetic similarity value of 0.609 grouped the 118 accessions into five groups. Mantel test meant that geographical origin and genetic distance presented positive correlation. The clustering results were consistent with known information on ecological growing areas. The genetic similarity coefficient of the accessions in the Loess Plateau ecotype was significantly lower than those in the other ecotypes. It indicates that the highest level of genetic diversity occurred in the Loess Plateau, which is probably the original site of Panicum miliaceum.

供磷水平对柳枝稷光合特性与抗逆生理的影响

【目的】探究盐碱条件下供磷水平对不同品种柳枝稷光合特性与抗逆生理的影响。【方法】采用双因素随机区组试验设计进行盆栽试验,设置3个柳枝稷品种(Alamo加倍体、Alamo和Path-finder)和3个供磷水平[不施磷(P0)、低磷10 mg/kg(P10)、高磷100 mg/kg(P100)],比较不同供磷水平下各品种柳枝稷光合特性、抗氧化酶活性、渗透调节物质含量的变化规律,综合评价不同柳枝稷品种抗逆性。【结果】柳枝稷叶片叶绿素a、b含量、净光合速率、气孔导度、蒸腾速率、脯氨酸含量随供磷水平的增加而增加,其中Alamo加倍体品种P100处理较P0处理分别增加了57.3%、62.9%、41.4%、29.7%、55.2%、128%;胞间CO_(2)浓度、过氧化氢酶活性(CAT)、可溶性糖含量(SS)随供磷水平的增加而降低,其中Alamo加倍体品种P100处理较P0处理分别降低了51.7%、84.4%、20.9%。高磷处理下Alamo加倍体的净光合速率、超氧化物歧化酶活性(SOD)和脯氨酸含量均最大,表现出较强的生理活性。【结论】盐碱条件下施磷提高了柳枝稷的光合能力和抗逆性,以高磷处理下Alamo加倍体的抗逆性最强。

东北春播区糜子核心种质及其DNA分子身份证构建

本研究以500份东北春播区糜子资源为材料,利用169个SSR标记,采用UPGMA聚类分组,进行分层抽样,构建核心种质,同时应用ID Analysis 4.0软件构建分子身份证。利用等位基因数(Na)等遗传多样性衡量指标评估核心种质的遗传差异,并利用PCOA分析核心种质。结果表明,对169对SSR引物进行筛选,发现30对多态性好,利用30对SSR引物构建的糜子核心种质包含190份材料,占全部种质的38%,全部种质与核心种质的均检测出91个等位变异,保留了100%等位基因;有效等位基因数为2.2977~2.9975和2.2872~3.0173,平均值分别为2.8198和2.8297;Shannon多样性指数为0.9532~1.0990和0.9535~1.1162,平均值为1.0645和1.0667;观测杂合度为0.3434~0.8037和0.3162~0.7849,平均值为0.5399和0.5359;期望杂合度为0.5654~0.6672和0.5645~0.6707,平均值为0.6448和0.6473;Nei’s基因多样性指数为0.5648~0.6664和0.5628~0.6686,平均值为0.6441和0.6452;多态性信息含量为0.6657~0.8356和0.6493~0.8340,平均值为0.7974和0.7944。全部种质与核心种质的分子标记的相关指标进行t检验,结果无显著性差异,且PCOA分析表明核心种质与全部种质具有相似的遗传多样性和群体结构,同时发现8个SSR标记(RYW5、RYW8、RYW16、RYW28、RYW40、RYW53、RYW62和RYW67)可区分190份核心种质,构建了东北糜子核心种质的分子身份证。

Functional characterization of caffeic acid O-methyltransferase in internode lignification of switchgrass(Panicum virgatum)

Caffeic acid O-methyltransferase(COMT) is a crucial enzyme that mainly methylates phenylpropanoid meta-hydroxyl of C5 in the biosynthesis of syringyl lignin in angiosperms. A putative COMT, named as PvCOMT1,was isolated from switchgrass(Panicum virgatum), a C4 warm-season dual-purpose forage and bioenergy crop. Our results showed that recombinant PvCOMT1 enzyme protein catalyzed the methylation of 5-OH coniferyl alcohol, 5-OH coniferaldehyde(CAld5H) and 5-OH ferulic acid. Further in vitro studies indicate that CAld5H can dominate COMT-mediated reactions by inhibiting the methylation of the other substrates. Transgenic switchgrass plants generated by an RNAi approach were further employed to study the function of COMT in internode lignification. A dramatic decrease in syringyl lignin units coupled with an obvious incorporation in 5-OH guaiacyl lignin units were observed in the COMT-RNAi transgenic plants. However, the constitutive suppression of COMT in switchgrass plants altered neither the pattern of lignin deposition along the stem nor the anatomical structure of internodes. Consistent with the biochemical characterization of PvCOMT1, a significant decrease in sinapaldehyde was found in the COMT-RNAi transgenic switchgrass plants, suggesting that CAld5H could be the optimal intermediate in the biosynthesis syringyl lignin.

糜子(Panicum miliaceum L.)全基因组YABBY基因家族鉴定与高渗溶液胁迫下表达特征

为系统了解糜子(Panicum miliaceum L.)YABBY基因家族成员及其特征,基于糜子基因组和注释数据,使用生物信息学的方法,鉴定分析了YABBY转录因子家族成员、染色体分布、蛋白特征、基因结构、进化关系、保守结构域、启动子区域的顺式作用元件及高渗溶液胁迫下表达特征。结果表明:糜子中含有17个YABBY基因,分别位于第1、2、3、4、5、6、12、15、16号染色体上,PmYABBY蛋白长度为125~935个氨基酸,等电点为5.70~10.33,家族成员含有3~13个内含子,通过亚细胞定位预测,所有成员都定位在细胞核中。利用MEGA7.0软件对拟南芥(Arabidopsis thaliana)、水稻(Oryza sativa)、玉米(Zea mays)、谷子(Setaria italica)和糜子YABBY基因家族的系统进化分析表明,17个糜子YABBY基因分为YAB1/YAB3、YAB2、CRC和INO 4个亚族。采用PlantCARE软件分析顺式作用元件发现,在糜子YABBY基因上游2 000 bp序列中,存在大量光应答和激素响应等种类和数目不同的顺式作用元件,表明该家族基因表达与光、激素等因素密切相关。幼苗期不同时间点PEG-6000高渗溶液胁迫下转录组测序数据分析显示,PmYABBY5、PmYABBY8、PmYABBY12、PmYABBY7、PmYABBY13、PmYABBY2、PmYABB9和PmYABBY7分别在地上器官(茎叶)、地下器官(根)中表达量变化较大,说明YABBY基因家族成员参与了非生物胁迫响应。研究结果可为糜子PmYABBY基因进一步功能解析和遗传利用提供科学依据。

Computational prediction and experimental verification of miRNAs in Panicum miliaceum L.

MicroRNAs (miRNAs) are a class of non-coding RNAs that play critical roles in post-transcriptional regulation. Their target genes are involved in a variety of biological processes such as development, metabolism, and stress response. Panicum miliaceum L. (Panicum) is an important grain crop, but, until now, no miRNAs have been identified in this plant. Using a homology search based on expressed sequence tag (EST) analysis and miRNA precursor secondary structure, a total of 43 new miRNAs were identified. The miRNAs were found to be unevenly distributed among 11 miRNA families. Target analysis using the plant small RNA target analysis server psRNATarget showed that the newly identified miRNAs can potentially regulate 68 target genes. Ten of the 11 miRNA families were annotated as involved in RNA regulation, suggesting they may play an essential role in post-transcriptional regulation in Panicum. Selected miRNAs representing eight of the families were verified by northern blotting, indicating that the prediction method that we used to identify the miRNAs was effective.