Genetic analysis and mapping of gene fzp ( t ) controlling spikelet differentiation in rice

A mutant of spikelet differentiation in rice called frizzle panicle (fzp) was discovered in the progeny of a cross between Oryza sativa ssp. indica cv. V20B and cv. Hua1B. The mutant exhibits normal plant morphology but has apparently fewer tillers. The most striking change in fzp is that its spikelet differentiation is completely blocked, with unlimited subsequent rachis branches generated from the positions where spikelets normally develop in wild-type plants. Genetic analysis suggests that fzp is controlled by a single recessive gene, which is temporarily named fzp(t). Based on its mutant phenotype, fzp(t) represents a key gene controlling spikelet differentiation. Some F₂ mutant plants derived from various genetic background appeared as the “middle type”, suggesting that the action of fzp(t) is influenced by the presence of redundant, modifier or interactive genes. By using simple sequence repeat (SSR) markers and bulked segregant analysis (BSA) method, fzp(t) gene was mapped in the terminal region of the long arm of chromosome 7, with RM172 and RM248 on one side, 3.2 cM and 6.4 cM from fzp(t), and RM18 and RM234 on the other side, 23.1 cM and 26.3 cM from fzp(t), respectively. These results will facilitate the positional cloning and function studies of the gene.     

对小麦顶生小穗的初步研究

1.顶生小穗的护颖具有特殊的形态,第二护颖常为小花外稃状,腋内有时还保留着雌雄蕊或内稃残余。说明其不稳定和可变的本质。2.顶生小穗具特殊的坐落位置,其小穗轴与主穗轴一致。顶生小穗原始体发生在穗生长锥顶端,其下无苞原始体,长成后也无小穗领。其护颖和小花外稃与侧生小穗下的小穗领呈严格连续互生状态。说明其一次轴的渊源。3.顶生小穗护颖腋内可长出小穗,小花也可代之以小穗,护颖和小花外稃有时以苞片的形式保留于新侧生小穗外侧。新顶生小穗的护颖来自小花外稃。说明顶生小穗护颖腋内的退化花芽、外稃腋内的小花与侧生小穗都是花序一次轴上的二次轴分枝。4.顶生小穗产生小穗的变异严格按自下而上的顺序进行,与原侧生小穗有严格的连续性。5.事实证明,顶生小穗是一次轴花序,它属于穗状花序顶端的可变部分。     

不同生育阶段夜温升高对双季水稻产量的影响

利用两间玻璃温室内夜间不同的温度条件,研究了水稻不同生育阶段的夜温升高对双季早、晚稻产量的影响.结果表明：播种-幼穗分化（一次枝梗分化期）期间夜温升高,有利于双季水稻的分蘖,植株有效穗数显著增加,平均夜间最低温度每升高1 ℃,双季早、晚稻的产量分别提高10.02%～13.18%和6.52%～7.78%（P＜0.01）;幼穗分化-抽穗（10%稻穗抽出剑叶鞘）期间夜温升高,导致颖花退化,使每穗发育颖花数减少,平均夜间最低温度每升高1 ℃,双季早、晚稻的产量分别下降3.76%～6.67%和3.66%～6.94%（P＜0.01）;灌浆结实期（抽穗-成熟）夜温升高,双季早稻的结实率和产量显著下降,而双季晚稻的结实率和产量显著提高,平均夜间最低温度每升高1 ℃,双季早稻的产量下降2.07%～5.61%（P＜0.05）,双季晚稻的产量提高1.63%～2.28%（P＜0.05）.表明不同生育阶段的夜温升高对双季水稻产量的影响存在明显差异.     

Source-sink manipulation effects on postanthesis photosynthesis and grain setting on spike in winter wheat

Source-sink manipulation could regulate the net photosynthetic rate (PN) of winter wheat after anthesis, however, the direction and magnitude of the regulation varied with time after anthesis. The PN was significantly increased by source reduction at the initial time of grain filling, but sink reduction had little influence on the PN, which suggested that the sink (spike) limitation did not occur at this time. Source-sink relation markedly affected PN during rapid grain filling. The PN was increased by source reduction and decreased by sink reduction significantly, which indicated that PN was closely associated with the change of source or sink size. The effect of source-sink manipulation on PN had some relationship with the occurrence of plant senescence at the time of late grain filling. Source reduction accelerated the senescence and dropped the PN, meanwhile, sink reduction delayed the senescence and promoted the PN. A direct relation between the effect of source-sink manipulation on PN and stomatal limitation was not found. Removing one quarter of leaves (RQ) had little influence on spike development after anthesis. In this case there was enough compensation in source production through photosynthesis. Removing one half of leaves (RH) made grain mass per spike and mass of grains lowered, especially the grain mass in the top and base positions of spike declined markedly. The source supply was grain-limiting. Removing one quarter of spikelets (RS) was beneficial to grain-setting in the remaining spikelets, leading to the increase of grain mass. Thus promoting the source supply of photosynthates after anthesis is of major importance for grain to set and to develop.     

麦类作物多胚的研究：Ⅱ.二棱大麦多胚苗的赝象

在麦类作物多胚的研究中,我们在２４个二棱大麦品系中,发现品系ＨＤ－２１的侧生小穗发育,且因位置偏移与中间小穗合生或粘连造成多胚的赝象。合生或粘连有６种形式,是可遗传的,遗传给后代植株的出现频率平均为１５．３８％,穗部出现合生或粘连的小穗一般为２％左右,最高达５０％。     

活血化瘀通络法联合针刺治疗对糖尿病下肢血管病变的影响

目的:探讨活血化瘀通络法联合针刺辅助治疗对糖尿病下肢血管病变(DLEAD)影响。方法:收集我院DLEAD患者90例,随机分为实验组1、实验组2和对照组。对照组予DLEAD基础治疗。实验组1在对照组基础上予以活血化瘀法中药治疗。实验组2在实验组1基础上加针刺治疗。对三组患者治疗前、治疗后进行FBG、P2h BG、Hb Alc测定,血清IL-6、ET-1水平测定及PAg T%、踝肱指数ABI测定。结果:1治疗后三组FBG、P2h BG、Hb Alc均下降,两组实验组较对照组均改善更明显,且实验组2下降更明显,差异有统计学意义(P0.05);2治疗后三组IL-6、ET-1及PAg T%均下降,两组实验组均比对照组改善更明显,实验组2下降更明显,差异有统计学意义(P0.05);3治疗后三组ABI均有所改善,两组实验组均更明显改善,且实验组2 ABI上升更明显,差异有统计学意义(P0.05)。结论:活血化瘀联合针刺治疗,可调节血清IL-6、ET-1水平,降低PAg T%,改善ABI,可有效提升DLEAD患者临床疗效,改善其预后,对提高患者生活质量有重要意义。     

Protein sequence redundancy reduction: comparison of various method

Non-redundant protein datasets are of utmost importance in bioinformatics. Constructing such datasets means removing protein sequences that overreach certain similarity thresholds. Several programs such as 'Decrease redundancy', 'cd-hit', 'Pisces', 'BlastClust' and 'SkipRedundant' are available. The issue that we focus on here is to what extent the non-redundant datasets produced by different programs are similar to each other. A systematic comparison of the features and of the outputs of these programs, by using subsets of the UniProt database, was performed and is described here. The results show high level of overlap between non-redundant datasets obtained with the same program fed with the same initial dataset but different percentage of identity threshold, and moderate levels of similarity between results obtained with different programs fed with the same initial dataset and the same percentage of identity threshold. We must be aware that some differences may arise and the use of more than one computer application is advisable.     

Identification and characterization of OsEBS,a gene involved in enhanced plant biomass and spikelet number in rice

Common wild rice (Oryza rufipogon Griff.) is an important genetic reservoir for rice improvement. We investigated a quantitative trait locus (QTL), qGP5‐1, which is related to plant height, leaf size and panicle architecture, using a set of introgression lines of O. rufipogon in the background of the Indica cultivar Guichao2 (Oryza sativa L.). We cloned and characterized qGP5‐1 and confirmed that the newly identified gene OsEBS (enhancing biomass and spikelet number) increased plant height, leaf size and spikelet number per panicle, leading to an increase in total grain yield per plant. Our results showed that the increased size of vegetative organs in OsEBS‐expressed plants was enormously caused by increasing cell number. Sequence alignment showed that OsEBS protein contains a region with high similarity to the N‐terminal conserved ATPase domain of Hsp70, but it lacks the C‐terminal regions of the peptide‐binding domain and the C‐terminal lid. More results indicated that OsEBS gene did not have typical characteristics of Hsp70 in this study. Furthermore, Arabidopsis (Arabidopsis thaliana) transformed with OsEBS showed a similar phenotype to OsEBS‐transgenic rice, indicating a conserved function of OsEBS among plant species. Together, we report the cloning and characterization of OsEBS, a new QTL that controls rice biomass and spikelet number, through map‐based cloning, and it may have utility in improving grain yield in rice.     

Effect of different temperatures to remove reduction gas on the photoluminescence properties of Eu‐doped Li2(Ba1‐xSrx)SiO4 phosphors

In this study, Eu‐doped Li₂(Ba_1‐xSr_x)SiO₄ powders (x = 0, 0.2, 0.4, and 0.6) were synthesized at 850°C in a reduction atmosphere (5% H₂ + 95% N₂) for a duration of 1 h using a solid‐state reaction method. The reduction atmosphere was infused as the synthesis temperature reached 850°C, and was removed as the temperature dropped to 800–500°C. Li₂(Ba_1‐xSr_x)SiO₄ (or Li₂BaSiO₄), (Ba,Sr)₂SiO₄ (or BaSiO₄), and Li₄SiO₄ phases co‐existed in the synthesized Eu‐doped Li₂(Ba_1‐xSr_x)SiO₄ powders. A new finding was that the reduction atmosphere removing (RAR) temperature of the Li₂(Ba_1‐xSr_x)SiO₄ phosphors had a large effect on their photoluminescence excitation (PLE) and PL properties. Except for the 800°C‐RAR‐treated Li₂BaSiO₄ phosphor, PLE spectra of all other Li₂(Ba_1‐xSr_x)SiO₄ phosphors had one broad emission band with two emission peaks centred at ~242 and ~283 nm; these PL spectra had one broad emission band with one emission peak centred at 502–514 nm. We showed that the 800°C‐RAR‐treated Li₂BaSiO₄ phosphor emitted a red light and all other Li₂(Ba_1‐xSr_x)SiO₄ phosphors emitted a green light. Reasons for these results are discussed thoroughly.