OsNPF3.1,a nitrate,abscisic acid and gibberellin transporter gene,is essential for rice tillering and nitrogen utilization efficiency

Low-affinity nitrate transporter genes have been identified in subfamilies 4-8 of the rice nitrate transporter 1(NRT1)/peptide transporter family(NPF),but the OsNPF3 subfamily responsible for nitrate and phytohormone transport and rice growth and development remains unknown.In this study,we described OsNPF3.1 as an essential nitrate and phytohormone transporter gene for rice tillering and nitrogen utilization efficiency(NUtE).OsNPF3.1 possesses four major haplotypes of its promoter sequence in 517 cultivars,and its expression is positively associated with tiller number.Its expression was higher in the basal part,culm,and leaf blade than in other parts of the plant,and was strongly induced by nitrate,abscisic acid(ABA)and gibberellin 3(GA_3)in the root and shoot of rice.Electrophysiological experiments demonstrated that OsNPF3.1 is a pH-dependent low-affinity nitrate transporter,with rice protoplast uptake assays showing it to be an ABA and GA_3 transporter.OsNPF3.1 overexpression significantly promoted ABA accumulation in the roots and GA accumulation in the basal part of the plant which inhibited axillary bud outgrowth and rice tillering,especially at high nitrate concentrations.The NUtE of OsNPF3.1-overexpressing plants was enhanced under low and medium nitrate concentrations,whereas the NUtE of OsNPF3.1 clustered regularly interspaced short palindromic repeats(CRISPR)plants was increased under high nitrate concentrations.The results indicate that OsNPF3.1 transports nitrate and phytohormones in different rice tissues under different nitrate concentrations.The altered OsNPF3.1 expression improves NUtE in the OsNPF3.1-overexpressing and CRISPR lines at low and high nitrate concentrations,respectively.

The auxin transporter OsAUX1 regulates tillering in rice(Oryza sativa)

Tillering is an important agronomic trait of rice(Oryza sativa)that affects the number of effective panicles,thereby affecting yields.The phytohormone auxin plays a key role in tillering.Here we identified the high tillering and semi-dwarf 1(htsd1)mutant with auxin-deficiency root characteristics,such as shortened lateral roots,reduced lateral root density,and enlarged root angles.htsd1 showed reduced sensitivity to auxin,but the external application of indole-3-acetic acid(IAA)inhibited its tillering.We identified the mutated gene in htsd1 as AUXIN1(OsAUX1,LOC_Os01g63770),which encodes an auxin influx transporter.The promoter sequence of OsAUX1 contains many SQUAMOSA PROMOTER BINDING PROTEIN-LIKE(SPL)binding sites,and we demonstrated that SPL7 binds to the OsAUX1 promoter.TEOSINTE BRANCHED1(OsTB1),a key gene that negatively regulates tillering,was significantly downregulated in htsd1.Tillering was enhanced in the OsTB1 knockout mutant,and the external application of IAA inhibited tiller elongation in this mutant.Overexpressing OsTB1 restored the multi-tiller phenotype of htsd1.These results suggest that SPL7 directly binds to the OsAUX1 promoter and regulates tillering in rice by altering OsTB1 expression to modulate auxin signaling.

Impact Damage Testing Study of Shanxi-Beijing Natural Gas Pipeline Based on Decision Tree Rotary Tiller Operation

The North China Plain and the agricultural region are crossed by the Shanxi-Beijing natural gas pipeline.Resi-dents in the area use rototillers for planting and harvesting;however,the depth of the rototillers into the ground is greater than the depth of the pipeline,posing a significant threat to the safe operation of the pipeline.Therefore,it is of great significance to study the dynamic response of rotary tillers impacting pipelines to ensure the safe opera-tion of pipelines.This article focuses on the Shanxi-Beijing natural gas pipeline,utilizingfinite element simulation software to establish afinite element model for the interaction among the machinery,pipeline,and soil,and ana-lyzing the dynamic response of the pipeline.At the same time,a decision tree model is introduced to classify the damage of pipelines under different working conditions,and the boundary value and importance of each influen-cing factor on pipeline damage are derived.Considering the actual conditions in the hemp yam planting area,targeted management measures have been proposed to ensure the operational safety of the Shanxi-Beijing natural gas pipeline in this region.

Tiller fertility is critical for improving grain yield,photosynthesis,and nitrogen efficiency in wheat

Genetic improvement has promoted wheat’s grain yield and nitrogen use efficiency(NUE)during the past decades.Therefore,the current wheat cultivars exhibit higher grain yield and NUE than previous cultivars in the Yangtze River Basin,China since the 2000s.However,the critical traits and mechanisms of the increased grain yield and NUE remain unknown.This study explores the mechanisms underlying these new cultivars’increased grain yield and NUE by studying 21 local cultivars cultivated for three growing seasons from 2016 to 2019.Significantly positive correlations were observed between grain yield and NUE in the three years.The cultivars were grouped into high(HH),medium(MM),and low(LL)grain yield and NUE groups.The HH group exhibited significantly high grain yield and NUE.High grain yield was attributed to more effective ears by high tiller fertility and greater single-spike yield by increasing post-anthesis single-stem biomass.Compared to other groups,the HH group demonstrated a longer leaf stay-green ability and a greater flag leaf photosynthetic rate after anthesis.It also showed higher N accumulation at pre-anthesis,which contributed to increasing N accumulation per stem,including stem and leaf sheath,leaf blade,and unit leaf area at pre-anthesis,and promoting N uptake efficiency,the main contribution of high NUE.Moreover,tiller fertility was positively related to N accumulation per stem,N accumulation per unit leaf area,leaf stay-green ability,and flag leaf photosynthetic rate,which indicates that improving tiller fertility promoted N uptake,leaf N accumulation,and photosynthetic ability,thereby achieving synchronous improvements in grain yield and NUE.Therefore,tiller fertility is proposed as an important kernel indicator that can be used in the breeding and management of cultivars to improve agricultural efficiency and sustainability.

PROG1 acts upstream of LAZY1 to regulate rice tiller angle as a repressor

Rice tiller angle,as a component of plant architecture,affects rice grain yield via plant density.However,the molecular mechanism underlying rice tiller angle remains elusive.We report that the key domestication gene PROSTRATE GROWTH 1(PROG1)controls rice tiller angle by regulating shoot gravitropism and LAZY1(LA1)-mediated asymmetric distribution of auxin.Acting as a transcriptional repressor,PROG1 negatively regulates the expression of LA1 in light-grown rice seedlings.Overexpression of LA1 partially rescued the larger tiller angle of the PROG1 complementation transgenic plant(prog1-D).Double-mutant analysis showed that PROG1 acts upstream of LA1 to regulate shoot gravitropism and tiller angle.Mutation of Suppressors of lazy1(SOL1),encoding DWARF3(D3)acting in the strigolactone signal pathway,suppressed the large tiller angle of prog1-D by rescuing the transcription of LA1.The discovery of a light-sensitive PROG1-LA1 transcription regulatory module controlling rice shoot gravitropism and tiller angle sheds light on the genetic control of rice tiller angle.

Advances in studies on the physiological and molecular regulation of barley tillering

Tillering is a crucial trait closely associated with yield potential and environmental adaptation in cereal crops,regulated by the synergy of endogenous(genetic)and exogenous(environmental)factors.The physiological and molecular regulation of tillering has been intensively studied in rice and wheat.However,tillering research on barley is scarce.This review used the recent advances in bioinformatics to map all known and potential barley tiller development genes with their chromosomal genetic and physical positions.Many of them were mapped for the first time.We also discussed tillering regulation at genetic,physiological,and environmental levels.Moreover,we established a novel link between the genetic control of phytohormones and sugars with tillering.We provided evidence of how environmental cues and cropping systems help optimize the tiller number.This comprehensive review enhances the understanding of barley’s physiological and genetic mechanisms controlling tillering and other developmental traits.

Genetic and environmental control of rice tillering

Increasing tiller number is a target of high-yield rice breeding. Identification of tiller-defect mutants and their corresponding genes is helpful for clarifying the molecular mechanism of rice tillering. Summarizing research progress on the two processes of rice tiller formation, namely the formation and growth of axillary meristem, this paper reviews the effects of genetic factors, endogenous hormones, and exogenous environment on rice tillering, finding that multiple molecular mechanisms and signal pathways regulating rice tillering cooperate rice tillering, and discusses future research objectives and application of its regulatory mechanism. Elucidation of theis mechanism will be helpful for breeding high-yielding rice cultivars with ideal plant type via molecular design breeding.

Identification of the candidate gene controlling tiller angle in common wheat through genome-wide association study and linkage analysis

Wheat tiller angle(TA)is an important agronomic trait that contributes to grain production by affecting plant architecture.It also plays a crucial role in high-yield wheat breeding.An association panel and a recombinant inbred line(RIL)population were used to map quantitative trait loci(QTL)for TA.Results showed that 470 significant SNPs with 10.4%–28.8%phenotypic variance explained(PVE)were detected in four replicates by a genome-wide association study(GWAS).Haplotype analysis showed that the TA_Hap_4B1 locus on chromosome 4B was a major QTL to regulate wheat TA.Ten QTL were totally detected by linkage mapping with the RIL population,and QTA.hau-4B.1 identified in six environments with the PVE of 7.88%–18.82%was a major and stable QTL.A combined analysis demonstrated that both TA_Hap_4B1 and QTA.hau-4B.1 were co-located on the same region.Moreover,QTA.hau-4B.1 was confirmed by bulked segregant RNA-Seq(BSR-Seq)analysis.Phenotypic analysis showed that QTA.hau-4B.1was also closely related to yield traits.Furthermore,Traes CS4B02G049700 was considered as a candidate gene through analysis of gene sequence and expression.This study can be potentially used in cloning key genes modulating wheat tillering and provides valuable genetic resources for improvement of wheat plant architecture.

Does Selection for Seedling Tiller Number in Perennial Biomass Feedstocks Translate to Yield and Quality Improvements in Mature Swards?

Breeding for seedling traits in herbaceous perennial biomass feedstocks that translate into increased biomass yield or quality in established swards could accelerate the development of perennial grass cultivars for bioenergy or forage. In previously reported research, breeding for single large tillers (ST) or multiple tillers (MT, ≥3) six weeks after planting for two generations in big bluestem (Andropogon gerardii Vitman) and switchgrass (Panicum virgatum L.) base populations produced ST and MT populations that differed significantly for seedling and mature plant traits including biomass yield in spaced planted nurseries. Our objective was to evaluate these ST and MT populations in sward trials to determine the effect of these genetic changes on biomass yield and quality when the plants were grown in competitive sward conditions. Big bluestem monocultures of the base, ST, and MT populations were evaluated at three locations in Nebraska in 2001 and 2002 as randomized complete block experiments with four replicates. Switchgrass monocultures of the base, ST, and MT populations were evaluated in 2003, 2004, and 2005 near Mead, NE as a randomized complete block with six replicates. In both big bluestem and switchgrass, the ST and MT populations did not consistently differ from the base population or each other for biomass yield or forage quality. These results demonstrate the importance of evaluating perennial grasses in sward trials and not relying solely on greenhouse-grown plants or space-planted nurseries to develop selection criteria and make selection decisions.

苏丹草和高丹草转录组测序及其差异基因表达分析

为了初步探明苏丹草[Sorghum sudanense(Piper) Stapf.]和高丹草[Sorghum bicolor(Linn.) Moench.×Sorghum sudanense(Piper) Stapf.]相关差异基因的表达,本研究对两者进行转录组测序,并对分蘖调控以及粗蛋白和木质素合成关联基因的差异表达进行分析。结果表明:与苏丹草相比,高丹草的单株分蘖数显著降低,粗蛋白、木质素和独角金内酯含量以及果糖激酶、苯丙氨酸解氨酶、多酚氧化酶、反肉桂酸4-单加氧酶活性显著提高,己糖激酶-3(HXK3)、果糖激酶2(FRK2)、天冬氨酸转氨酶(ASPAT)、S-腺苷甲硫氨酸合成酶1(SAMS1)、多酚氧化酶II(PPOII)、双功能天冬氨酸激酶/高丝氨酸脱氢酶2(AKI/DHI2)、苯丙氨酸解氨酶(PAL)、反-肉桂酸4-单加氧酶(C4H)基因表达上调,独角金内酯酯酶D14(SLsE D14)基因表达下调。本研究为苏丹草和高丹草相关功能基因的克隆、分子标记开发等工作奠定了基础。

水稻群体分蘖动态模型构建与应用

为定量分析水稻群体茎蘖数量动态变化过程及分蘖动态特征,该研究使用双Logistic模型分别描述分蘖发生与死亡过程,建立水稻群体分蘖动态模型;根据水稻分蘖过程的时序特征定义描述分蘖过程的特征指标,并推导出分蘖特征指标的计算式;基于不同基因型品种的种植方式、种植时期、种植密度下水稻分蘖动态数据集检验模型优度和适应性;并应用分蘖动态模型和指标探索分蘖动态对种植密度的响应规律。结果表明,所建模型对不同基因型水稻品种在不同种植方式、种植时期和种植密度下的分蘖动态数据拟合优度较好,标准均方根误差S_(RMSE)服从均值小于5%的Gamma分布,并且99%的S_(RMSE)小于10%。基于所建模型计算的分蘖特征指标(包括模型参数)对种植密度有很好的响应;留一法检验表明模型的预测性较好,观测值与模拟值的R^(2)=0.96。所建模型能够精确描述水稻茎蘖数量演变过程,具有很好的拟合优度、适应性和可解释性,可用于分析基因、环境、农艺措施对分蘖动态的影响,分蘖特征指标可望成为分析基因与环境互作的重要表型参数,对指导水稻精准栽培也有重要理论价值和实际意义。

基于动力吸振器的微耕机扶手架减振设计

微耕机的扶手架结构较为简单,在田间作业时会造成扶手架的强烈振动,长时间的强烈振动会给操作者身心带来不适甚至严重伤害,针对此问题,对微耕机扶手架进行了减振设计。对于结构相对简单的构件,振动问题大多是由于主振动系统自身结构阻尼的不足导致的。为此,结合微耕机实际情况,将动力吸振器的设计方法应用于微耕机扶手架上,对动力吸振器进行结构设计并试制样件。最后,对动力吸振器样件的减振效果进行试验测试,结果表明:在安装动力吸振器样件后,其手把处的振动强度在空挡和耕作状态下分别降低了13.9%和11.2%。

水稻矮化多蘖突变体mtd2/htd1-1的鉴定与图位克隆

株高是株型构成的重要因子,分蘖则是有效穗形成的基础,二者均是水稻重要的农艺性状.为研究株高和分蘖发育的分子机理,用甲基磺酸乙酯(EMS)诱变保持系西大1B,从中鉴定到1个矮化多蘖突变体,命名为mtd2(more tiller and dwarfism 2).与野生型西大1B相比,mtd2的分蘖数(70.00个)是野生型的6.25倍,株高(49.12 cm)则为野生型的59.4%,同时还表现出小穗、短叶等特征.遗传分析表明:mtd2分蘖增多和植株矮化的突变表型呈共分离现象且受单隐性核基因调控.利用mtd2和缙恢10号杂交组合的F2隐性群体,最终将MTD2基因精细定位于第4染色体分子标记C04-2和C04-3之间157 kb的物理范围内,该区间内含1个已克隆的多蘖矮秆基因LOC_Os04g46470-HTD1.对定位区间内的HTD1进行DNA测序,发现其编码区有11个碱基缺失,导致移码突变.构建互补载体,转化突变体mtd2,其矮化多蘖表型恢复正常,表明mtd2是htd1的一个新等位突变体.细胞学分析发现:mtd2分蘖数增多是由于分蘖芽发育较快所致;qRT-PCR分析表明:MTD2可能参与独脚金内酯(SLs)相关的分蘖芽发育调控网络,这为进一步鉴定MTD2/HTD1基因的功能奠定了基础.

不同季秸秆还田对冬小麦不同穗粒位结实粒数和粒重的影响

为探讨安徽淮北平原砂姜黑土区长期秸秆连续全量还田对冬小麦穗部结实特性的影响,2021-2022年基于农业农村部华东地区作物栽培科学观测站13年的长期定位试验,比较分析了小麦单季秸秆全量粉碎覆盖还田(T1)、小麦玉米秸秆全量粉碎还田(T2)、玉米秸秆全量粉碎翻埋还田(T3)、小麦玉米秸秆全年不还田(CK)4个不同还田模式下小麦不同小穗位结实粒数及粒重的差异。结果表明,T1、T2、T3处理的主茎穗小穗结实总粒数较CK分别提高了21.21%、7.50%和12.55%;第2粒位(G2)结实粒数分别提高了7.71%、7.71%和5.79%;上部小穗结实粒数分别提高了51.41%、22.79%和31.36%,其G2结实粒数分别提高了30.95%、30.95%和23.09%,其中T1处理对小麦粒数的提升效果最好。不同季秸秆还田处理下小麦主茎穗及其G2粒重、分蘖穗及其第三粒位(G3)粒重均高于CK,T1、T2和T3处理的主茎穗粒重增幅分别为16.06%、4.14%和16.06%,分蘖穗增幅分别为9.86%、0.71%和8.87%;T1、T2和T3处理下主茎穗G2粒重增幅分别为20.69%、10.34%和17.24%,分蘖穗G3粒重4.55%、2.27%和6.82%,其中T1处理对粒重提升效果最好,其次是T3。综合来看,在安徽淮北平原砂姜黑土区长期秸秆还田能够提高小麦穗粒数和粒重,进而促进产量提升,其中T1处理对小麦结实粒数和粒重的提升效果最好,是适宜在该地区推广的秸秆还田模式。

达芬奇手术机器人患者手术平台组成原理及故障检修案例分析

随着“精准医疗”理念的推广,达芬奇手术机器人在外科手术中的应用日益受到重视,该机器人系统由医生控制平台、影像处理平台和患者手术平台组成,能够实现高精度、微创的外科手术。患者手术平台是其核心部分,包含多条机械臂和舵柄,舵柄具有快速定位、灵活性和精确控制等功能,确保手术的顺利进行。尽管达芬奇手术机器人在技术上具有显著优势,但其高昂的费用和复杂的维护需求使得医院面临挑战。为提升医院自身的维修维护能力,重点分析达芬奇手术机器人患者手术平台的组成原理,尤其是舵柄的构造与工作原理,并通过对患者手术平台具体的故障案例分析,探讨常见故障的检修方法,以期为医院提供有效的维护策略,降低运营成本,提升医疗效益。

根蘖与嫁接繁殖灵武长枣不同时期果实差异表达基因分析

【目的】研究灵武长枣根蘖繁殖与嫁接繁殖果实品质差异的内在机理,为提高其果实品质提供基础数据。【方法】以灵武长枣根蘖繁殖与嫁接繁殖白熟期(NB)、着色期(NZ)、成熟期(NC)和嫁接繁殖白熟期(JB)、着色期(JZ)、成熟期(JC)的果实为试验材料,采用高通量测序技术进行果实转录组测序,筛选与根蘖和嫁接繁殖的灵武长枣果实品质差异相关的基因,初步探究根蘖和嫁接繁殖灵武长枣果实不同时期基因表达差异情况。【结果】18个灵武长枣样品经过转录组测序,得到质控数据138.26 GB,将其比对到参考基因组冬枣上,18个样品的Cleans reads与参考基因组比对效率在93.77%以上。主成分分析结果显示,3次生物学重复样品聚集程度较高且组间存在分离现象,说明其基因表达量存在差异。差异分析结果表明,灵武长枣果实发育各时期组间分析对比中,果实白熟期(JB-vs-NB)、着色期(JZ-vs-NZ)和成熟期(JC-vs-NC)各组间分别筛选出65、4 509和1 534个差异基因。GO功能富集到生物过程、分子功能和细胞组分三大类中的50个亚类中,KEGG通路注释将差异基因显著富集在次生代谢物生物合成、代谢途径、氨基酸生物合成等通路中,成熟期差异基因富集在糖酸相关通路的显著性较高。【结论】在淀粉和蔗糖代谢、半乳糖代谢、氨基糖和核苷酸糖代谢,乙醛酸和二羧酸代谢、丁酸代谢5条与果实可溶性糖和总酸含量相关的代谢途径中筛选出了ncbi_107424266、ncbi_107414286、ncbi_107425230、ncbi_107429837等31个差异基因,分别在果实发育不同时期的糖酸代谢途径中差异表达,调控各时期果实中可溶性糖及总酸含量。

大白菜莲座叶大叶夹角和多分蘖材料的创制及其应用

为加快小株型、适合高密度种植的大白菜品种和多分蘖的不结球白菜、菜薹品种选育,进而改良大白菜种植模式,提高大白菜产量和品质,以大白菜、菜心、红菜薹为材料,采用常规杂交方法进行三亲本杂交,以期创制新的种质材料;同时,以创制的大白菜21M-193为亲本和大白菜白阳杂交,构建6世代遗传群体,研究大白菜莲座叶叶夹角和分蘖的遗传和应用。结果表明:多亲本间杂交创制的大白菜材料21M-193具有大叶夹角和多分蘖的特性。经测量,21M-193平均叶夹角度数为82.7°,白阳平均叶夹角度数为30.5°,两者杂交F_(1)代平均叶夹角度数为40.7°,偏向于白阳,表现为小叶夹角表型。F2代单株叶夹角则呈现正态分布,小于10°和大于84°的极端个体很少,30°~50°的中间类型占绝大多数,其分离比例不符合孟德尔遗传规律,推测大白菜莲座叶叶夹角遗传是由多基因控制的数量性状。此外,调查发现21M-193分蘖数达到28个/株,白阳分蘖数为7个/株,其F_(1)代分蘖数为18个/株,居于中间,偏向于21M-193。研究结果不仅创制了大叶夹角和多分蘖的大白菜新种质,而且初步揭示了大白菜叶夹角和分蘖性状的遗传规律,还为这两个重要农艺性状的基因定位与分子辅助育种提供了宝贵的材料和数据支持,对推动大白菜品种改良及高产、优质栽培模式创新具有重要意义。

基于YOLOv5m和CBAM-CPN的单分蘖水稻表型参数提取

为快速获取单分蘖水稻植株的形态结构和表型参数,该研究提出了一种基于目标检测和关键点检测模型相结合的骨架提取和表型参数获取方法。该方法基于目标检测模型生成穗、茎秆、叶片的边界框和类别,将所得数据分别输入到关键点检测模型检测各部位关键点,按照语义信息依次连接关键点形成植株骨架,依据关键点坐标计算穗长度、茎秆长度、叶片长度、叶片-茎秆夹角4种表型参数。首先,构建单分蘖水稻的关键点检测和目标检测数据集;其次,训练Faster R-CNN、YOLOv3、YOLOv5s、YOLOv5m目标检测模型,经过对比,YOLOv5m的检测效果最好,平均精度均值(mean average precision,mAP)达到91.17%;然后,应用人体姿态估计的级联金字塔网络(cascaded pyramid network,CPN)提取植株骨架,并引入注意力机制CBAM(convolutional block attention module)进行改进,与沙漏网络(hourglass networks,HN)、堆叠沙漏网络模型(stacked hourglass networks,SHN)和CPN模型相比,CBAM-CPN模型的预测准确率分别提高了9.68、8.83和1.06个百分点,达到94.75%,4种表型参数的均方根误差分别为1.06 cm、0.81 cm、1.25 cm和2.94°。最后,结合YOLOv5m和CBAM-CPN进行预测,4种表型参数的均方根误差分别为1.48、1.05、1.74cm和2.39°,与SHN模型相比,误差分别减小1.65 cm、3.43 cm、2.65 cm和4.75°,生成的骨架基本能够拟合单分蘖水稻植株的形态结构。所提方法可以提高单分蘖水稻植株的关键点检测准确率,更准确地获取植株骨架和表型参数,有助于加快水稻的育种和改良。

激素调控植物分枝/分蘖的研究进展

分枝/分蘖是植物株型的一个重要特征,也是腋芽起始和芽生长的结果,对经济作物的种子产量以及牧草产量均具有决定性作用。多种激素及其互作效应在植物分枝/分蘖的发生和生长发育过程中起着关键的调控作用,且环境因素也是通过改变植物体内激素含量及其平衡调控分枝的。本研究综述了多种激素对植物分枝/分蘖调控机制的多个方面,包括生长素、细胞分裂素、独脚金内酯、油菜素内酯、脱落酸和赤霉素、乙烯、茉莉酸及不同激素信号相互作用形成的复杂调控网络,旨在为利用激素调控机制培育具有理想株型的高产新作物品种奠定基础。同时分析了激素机制调控植物分枝/分蘖的现存问题,并展望了激素调控植物分枝/分蘖的研究方向,以期为通过激素调控改良作物株型提供理论依据。

甘蔗硝酸盐转运蛋白1/肽转运蛋白家族6.4基因(ScNPF6.4)克隆及其调控分蘖功能分析

甘蔗(Saccharum spp.hybrid)是重要的糖料和能源作物,分蘖是影响其产量的重要性状之一。硝酸盐转运蛋白1/肽转运蛋白家族(NITRATE TRANSPORTER 1(NRT1)/PEPTIDE TRANSPORTER(PTR)family,NPF)成员在植生长发育中发挥重要作用,甘蔗中NPF基因的挖掘利用可为甘蔗品种分蘖遗传调控和产业升级奠定重要基础。本研究通过前期转录组数据结合反转录PCR(reverse transcription PCR,RT-PCR)从甘蔗品种ROC22中获得其NPF家族成员6.4基因的cDNA全长序列(命名为ScNPF6.4),并对其进行序列结构、理化性质、系统进化等分析,然后开展了该基因在苗期甘蔗中的组织特异性、甘蔗腋芽萌发过程中的表达情况以及响应激素处理的表达模式分析,最后将该基因遗传转化水稻过表达进行功能验证。结果表明,ScNPF6.4的cDNA包含1个1806 bp的开放阅读框,编码601个氨基酸,属于易化子超家族(major facilitator superfamily,MFS)蛋白,其蛋白分子量为63.9 kD,理论等电点为9.23,包含12个跨膜螺旋区。该蛋白不存在信号肽,具疏水性,属于一类稳定的非分泌蛋白,系统进化分析表明其属于NPF 6.4亚族蛋白。亚细胞定位分析表明该蛋白定位于内质网。组织特异性分析发现,ScNPF6.4在苗期甘蔗根中相对表达量最高,在叶和茎基部相对表达量较低;ScNPF6.4在不同甘蔗品种腋芽萌发阶段均上调表达;适量浓度的植物外源激素6-BA、ABA、GA3、IBA、乙烯利和SLs均能诱导苗期甘蔗中ScNPF6.4的上调表达;水稻中异位过表达ScNPF6.4可增加水稻分蘖数并提前孕穗。以上结果表明,ScNPF6.4正调控甘蔗分蘖芽萌发,其表达受外源植物激素调控,该基因过表达可增加水稻分蘖数并促进提前孕穗,克隆该基因可为甘蔗分蘖早生快发高产育种提供重要的基因资源。