影响籼稻花药培养诱导率的因素及基因型的作用研究

本文研究了影响籼稻花药培养诱导率的9种重要因素的作用。供试品种和杂种共70余种。结果发现,不同基因型的培养力存在很大差异,这种差异表现在对各种因素上,如基本培养基成分、激素的种类与配比、对低温预处理的时间等等不同反应上。低温预处理是提高籼稻出愈率的有效措施,但由于不同基因型小孢子对低温的耐受力不同,所需的适合预处理时间也就不同。花药接种后先在30℃下培养3天后,再转入26℃下培养,较直接培养在26℃下可大幅度提高花粉檀株的产量。诱导培养基中补加脯氨酸、马铃薯提取液对提高出愈率和绿苗分化率有明显效果。     

景谷芒果老果园更新改造的试验研究

本试验旨在针对１个早衰低产、行将淘汰的芒果老果园进行几种更新改造模式的探索性试验,以为景谷全县现存数万株芒果老果树的更新复壮作出示范和提供科学依据。自１９９１年采果后,对此１０ｈｍ＾２２０６４株的老果园分别采取轻度更新、隔行更新、强度更新与轻度修剪４种模式,并使命以其它农艺措施（定期防治病虫害、坡改台、增施肥料）加强管理。在原有大芒果树仅保留１１００株的情况下,１９９３年全园总产量达４４３６０ｋｇ     

Production of aromatic three-line hybrid rice using novel alleles of BADH2

Aroma is a key grain quality trait that directly influences the market price of rice globally. Loss of function of betaine aldehyde dehydrogenase 2 (OsBADH2) affects the biosynthesis of 2-acetyl-1-pyrroline (2-AP), which is responsible for aroma in fragrant rice. The current study was aimed at creating new alleles of BADH2 using CRISPR/Cas9 gene editing technology under the genetic background of the japonica Ningjing 1 (NJ1) and indica Huang Huazhan (HHZ) varieties. Sensory evaluation and analysis using headspace solid-phase microextraction gas chromatography–mass spectrometry (HS-SPME-GC-MS) showed that the grains of the four homozygous T₁ lines with new alleles of BADH2 (nj1-cr ^BADH2-1, nj1-cr ^BADH2-2, hhz-cr ^BADH2-1 and hhz-cr ^BADH2-2) produced moderate fragrance and had significantly increased 2-AP content compared with wild-types. Moreover, there were no significant differences in the amylose content and gelatinization temperature among the four lines with new alleles of BADH2 to the wild-types. Thereafter, we crossed the HHZ background new alleles of BADH2 with CMS line Taonong 1A (TN1A) to produce a three-line hybrid variety B-Tao-You-Xiangzhan (BTYXZ) with increased grain aroma. The 2-AP content in grains of the improved BTYXZ-1 and BTYXZ-2 reached at 26.16 and 18.74 μg/kg, and the gel consistency of BTYXZ-1 and BTYXZ-2 increased significantly by 9.1% and 6.5%, respectively, compared with the wild-type Tao-You-Xiangzhan (TYXZ). However, the γ-aminobutyric acid (GABA) content in the improved three-line hybrid rice BTYXZ-1 (5.6 mg/100 g) and BTYXZ-2 (10.7 mg/100 g) was significantly lower than that of the TYXZ. These results demonstrated that CRISPR/Cas9 gene editing technology could be successfully utilized in improving aroma in non-fragrant japonica and indica varieties. In addition, the newly developed BADH2 alleles provided important genetic resources for grain aroma improvement in three-line hybrid rice.     

Adaptive plasticity in response to light and nutrient availability in the clonal plant Duchesnea indica

克隆植物蛇莓对光照强度和养分条件的适应性可塑性 表型可塑性可帮助植物缓冲环境压力并使其表型与当地环境相匹配,但目前仅少数性状的可塑性被广泛认为是适应性的。为充分理解可塑性的适应性意义,仍需进一步研究更多的植物功能性状及其环境因子。本研究将匍匐茎克隆植物蛇莓(Duchesnea indica)的21个基因型种植于不同的光照和养分条件下,并利用选择梯度分析检测了形态和生理可塑性对光照强度和养分有效性变化的适应性值。在遮荫条件下,蛇莓适合度(果实数、分株数和生物量)降低,节间缩短变细,成熟叶叶绿素含量降低,但叶柄长度、比叶面积、老叶叶绿素含量均增加。在低养分条件下,植株叶柄缩短,叶面积缩小变厚,叶绿素含量降低,但果实数量和根冠比增加。选择梯度分析表明,叶柄长度和老叶叶绿素含量对光照变化的可塑性是适应性的,老叶和成熟叶叶绿素含量对养分变化的可塑性也是适应性的。因此,不同性状的可塑性适应值取决于特定的生态背景。该研究的发现有助于理解克隆植物表型可塑性响应环境变化的适应性意义。     

Isolation of quinic acid derivatives and flavonoids from the aerial parts of Lactuca indica L. and their hepatoprotective activity in vitro

In our continuing study of biologically active compounds from Korean medicinal plants, we investigated the hepatoprotective constituents of the aerial parts of Lactuca indica L. (Compositae), since the methanolic extract of L. indica has hepatoprotective activity against hepatitis B virus (HBV) production. The bioactivity-guided separation of the methanolic extract of the aerial parts of L. indica resulted in the isolation of seven quinic acid derivatives (1, 3–4, 6, and 10–12), along with five flavonoids (2, 5, and 7–9). All the isolated compounds were evaluated for hepatoprotective activity by the HBV assay in vitro. In the human HBV-transfected liver cell line HepG2.2.15, all the compounds except 2 and 5 effectively reduced HBV DNA level in the release of mature HBV particles from HepG2.2.15 cultivation. Of the ten active compounds, treatment with 1, 3, and 12 led to significant reduction in the extracellular HBV DNA level, suggesting that they could be potent phytochemical agents against hepatitis B virus.     

ISSR鉴定亲缘关系非常近的芒果栽培品种

用ISSR技术鉴定7个吕宋芒品种(系)和柳州吕宋芒。从30个引物中筛选出6个多态性好的ISSR引物建立DNA指纹图谱用于区分吕宋芒品种(系)。分析DNA指纹图谱,发现这6个引物中每个引物都能区分吕宋系列品种(系),表明ISSR-PCR技术对芒果品种(系)的鉴定非常有效,能区分亲缘关系很近的品种(系)。基于69条多态性条带的聚类分析结果,发现吕宋芒和其它供试的7个品种(系)同源性低,而这7个品种(系):高州吕宋芒、湛江吕宋芒、田阳香芒、金钱芒、柳州吕宋芒、粤西一号、攀西红吕宋同源性较高,可归为一类。     

应用SSP-PCR/SSO方法进行中国辽宁汉族人HLA-DRB1基因的遗传多态性研究

对159名中国辽宁汉族个体的基因组DNA进行分析,共检出42种等位基因,其中以DRB1*09012(12.8%)、*0701(10.7%)、*1501(10.4%) 最为常见,其次为DRB1*1201(7.9%)、*1202(7.5%)、*1101(6.6%)、*0301(5.0%)。并发现辽宁汉族人DRB1等位基因频率与白种人间存在明显差异,揭示不同人种有其自己的主要等位基因。同时对本技术在HLA-DRB1分型应用中的优点进行了讨论。 Abstract　HLA-DRB1 alleles of 159 Chinese donors from Liaoning Han population were determined by using a set of 23 sequence specific oligonucleotide probes directed to various DRB1 alleles. The samples were first amplified and divided into 8 groups by allele/group specific primers. The SSOs enable us to identify 58 different DRB1subtypes. 42 alleles were detected in the study of this population. Among them, the DRB1*09012(12.8%), *0701(10.7%), *1501(10.4%), *1201(7.9%), *1202(7.5%), *1101(6.6%), *0301(5.0%) are the most frequent. The significant difference was found in Chinese northern Han population by comparing the gene frequencies in Caucasoid samples, suggesting that there were principal DRB1 alleles in different races.     

Changes in Chlorophyll Content and Photosynthetic Rate of Four Cultivars of Mango during Reproductive Phase

Total chlorophyll (Chl) content, leaf mass per area (LMA), and net photosynthetic rate (P_N) were studied in four cultivars of mango (Mangifera indica L.) from September to May. Maximum Chl contents were found in September and December, the period considered to be crucial for flowering in mango. P_N was maximum during October and maintained almost steady during the fruit growth period. However, LMA varied significantly in all cultivars. Mean Chl content, P_N and LMA were lower in cv. Malaviyabhog than in other cultivars. This revised version was published online in June 2006 with corrections to the Cover Date.     

Inheritance of resistance to anti-microtubule dinitroaniline herbicides in an “intermediate” resistant biotype of Eleusine indica (Poaceae)

Inheritance of resistance to the anti-microtubule dinitroaniline herbicides was investigated in a goosegrass biotype displaying an intermediate level of resistance (I). Reciprocal crosses were made between the I biotype and previously characterized susceptible (S) or resistant (R) biotypes. Eight F₁ hybrids were identified, and F₂ populations were produced by selfing. The dinitroaniline-herbicide response phenotype (DRP) of F₁ plants, and F₂ seedlings was determined using a root-growth bioassay. The DRP of F₁ plants of S × I was “susceptible” (i.e., identical to the S parental plants), and the DRP of F₁ plants of I × R was “intermediate” (i.e., identical to the I parental plants). Nonparental phenotypes were not observed in F₁ plants. Results indicated susceptibility to be dominant over intermediate resistance and intermediate resistance to be dominant over high resistance. Analysis of reciprocal crosses ruled out any role for cytoplasmic inheritance. When treated at the discriminating concentration (e.g., 0.28 ppm oryzalin), F₂ seedlings of S × I were classified as either S or I phenotype, and F₂ seedlings of I × R were classified as either I or R phenotype. Again, nonparental phenotypes were not observed. The 3:1 (S:I or I:R) segregation ratios in F₂ seedlings were consistent across all eight F₂ families. The results show that dinitroaniline herbicide resistance in the I biotype of goosegrass is inherited as a single, nuclear gene. Furthermore, it suggests that dinitroaniline resistance in goosegrass is controlled by three alleles at a single locus (i.e., Drp-S, Drp-i, and Drp-r).     

Cleistogamy in Scutellaria indica (Labiatae): effective mating system and population genetic structure

Scutellaria indica is a perennial herb with both chasmogamous (CH) and cleistogamous (CL) flowers on the same plant in some populations, and only CL flowers in other populations. Actual seed production by CH and CL flowers was investigated in populations of S. indica. The average seed set of CL flowers was 19 times higher than CH flowers, indicating much greater fertilization success. The CL seeds were also significantly heavier than the CH seeds. However, the resource cost of producing a CH flower was much higher than that of producing a CL flower. The CH flower was approximately seven times larger, and its pollen/ovule ratio was approximately five times higher than flowers. The level and pattern of genetic diversity at both allozyme and random amplified polymorphic DNA (RAPD) levels were consistent with a predominantly selfing system in the species. The average amount of within-population genetic variation was extremely low (A = 1.025, P = 2.36%, HO = 0.001 and HE = 0.008 based on allozyme data, and P = 8.94% and HE = 0.03 based on RAPD data). At the species level, the estimates of total gene diversity (HT) were 0. 101 based on allozyme data and 0.139 based on RAPD data. A very high level of genetic differentiation occurred between populations (allozyme GST = 0.92 and RAPD GST = 0.81). Genetic drift coupled with predominant cleistogamous selfing apparently played the major role in determining the population genetic structure in S. indica. Although the features associated with CH and CL flower and seed production seem to be sufficient for the evolution of complete cleistogamy in S. indica, random fixation of alternative alleles for dimorphic or complete cleistogamy in small populations could maintain the multiple strategy of chasmogamous and cleistogamous reproduction in the species.