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331.
New blue whale ovarian corpora data from illegal Soviet catches in the Southern Hemisphere and northern Indian Ocean were recovered from the original logbooks. Catches north of 52°S were assumed to be pygmy blue whales ( Balaenoptera musculus brevicauda , n = 1,272); those south of 56°S were assumed to be Antarctic (true) blue whales ( B. m. intermedia , n = 153). Three probable Antarctic blue whales north of 52°S were excluded. Lengths at which 50% and 95% of females become sexually mature ( L 50 and L 95 ) were estimated from a Bayesian logistic model. These estimates are more precise than previous Japanese estimates because Soviet catches below the legal minimum of 70 ft (21.3 m) were 32 times greater. For pygmy blue whales L 50 was 19.2 m (95% interval 19.1–19.3 m) and L 95 was 20.5 m (95% interval 20.4–20.7 m). Antarctic L 50 (23.4 m, 95% interval 22.9–23.9 m) was much longer than L 50 for pygmy blue whale regions (18.4–19.9 m). The median L 50 for the northern Indian Ocean was 0.5–0.6 m shorter than for pygmy blue whales from other regions; although statistically significant, these small length differences provide little support for northern Indian Ocean blue whales being a separate subspecies, B. m. indica . 相似文献
332.
Joyeeta Biswas Bikash Chowdhury A. Bhattacharya A. B. Mandal 《In vitro cellular & developmental biology. Plant》2002,38(5):525-530
Summary
In vitro screening at the cellular level was performed with mature seed-derived callus from five rice varieties, viz. IR 18351-229-3,
IR 3185-6-3-3-2, SR 26-B, Nona Bokra, and C 14-8 of diverse geographical origin and with differential drought resistance at
the in planta level. Callus was induced from mature seeds on Murashige and Skoog medium supplemented with 2.0 mgl−1 (9 μM) of 2,4-dichlorophenoxyacetic acid (2,4-D) and 5.0, 10.0, and 15.0 gl−1 of high molecular weight polyethylene glycol (PEG, 6000) as stressing agent to create chemical drought. Simultaneous efforts
were also made to assess the effects of chemical drought in altering morphogenetic response in different varieties under in vitro culture. Seed germination was almost unaffected in SR 26-B and C 14-8, unlike in other varieties where germination was seriously
affected. In general, seed germination was found to be decreased in three genotypes, viz. IR 18351-229-3, IR 3185-6-3-3-2,
and Nona Bokra, with increased PEG concentrations. All genotypes displayed callus induction percentage in decreasing order
with increased PEG concentrations supplemented in the callus induction medium (CIM), except SR 26-B and Nona Bokra. Callus
induction was found to be more on CIM fortified with 5.0 gl−1 PEG. In general, embryogenic callus induction and plantlet regeneration was found to be indirectly proportional to increased
PEG concentrations used in CIM. Considering all characters, C 14-8 was found to be most appropriate in developing drought-tolerant
lines under in vitro culture conditions followed by SR 26-B and Nona Bokra. A number of putative drought-tolerant plants were developed in C 14-8,
SR 26-B, Nona Bokra, and IR 18351-29-3, and forwarded for field evaluation. In the majority of the progenies, a monogenic
inheritance pattern for the drought tolerance character was observed. 相似文献
333.
为了揭示印楝(Azadirachta indica)实生种群表型变异程度和变异规律, 以云南引种印楝人工林为研究对象, 基于9个种群90个单株14个表型性状严格细致的测量, 采用单因素方差分析、巢式方差分析、相关分析、协方差主成分分析(S法)和非加权配对算术平均法(UPGMA)聚类分析等数理方法, 分析了种群的表型变异。结果表明: 印楝种内表型性状在种群间和种群内均存在着较丰富的差异, 种群内的变异大于种群间的变异, 种群间的分化相对较小。对表型性状进行的变异系数多重比较和协方差主成分分析(S法)均显示, 结实和种子化学成分相关性状的变异是造成印楝表型变异的主要来源。利用种群间欧氏距离进行的UPGMA聚类分析结果进一步表明, 印楝9个种群可以分为4类, 表型性状并没有严格依地理距离而聚类。研究结果为印楝的遗传改良工作奠定了基础, 为制定育种策略和人工经营对策提供了科学依据。 相似文献
334.
Datta K Baisakh N Oliva N Torrizo L Abrigo E Tan J Rai M Rehana S Al-Babili S Beyer P Potrykus I Datta SK 《Plant biotechnology journal》2003,1(2):81-90
Vitamin-A deficiency (VAD) is a major malnutrition problem in South Asia, where indica rice is the staple food. Indica-type rice varieties feed more than 2 billion people. Hence, we introduced a combination of transgenes using the biolistic system of transformation enabling biosynthesis of provitamin A in the endosperm of several indica rice cultivars adapted to diverse ecosystems of different countries. The rice seed-specific glutelin promoter (Gt-1 P) was used to drive the expression of phytoene synthase (psy), while lycopene beta-cyclase (lcy) and phytoene desaturase (crtI), fused to the transit peptide sequence of the pea-Rubisco small subunit, were driven by the constitutive cauliflower mosaic virus promoter (CaMV35S P). Transgenic plants were recovered through selection with either CaMV35S P driven hph (hygromycin phosphotransferase) gene or cestrum yellow leaf curling virus promoter (CMP) driven pmi (phophomannose isomerase) gene. Molecular and biochemical analyses demonstrated stable integration and expression of the transgenes. The yellow colour of the polished rice grain evidenced the carotenoid accumulation in the endosperm. The colour intensity correlated with the estimated carotenoid content by spectrophotometric and HPLC analysis. Carotenoid level in cooked polished seeds was comparable (with minor loss of xanthophylls) to that in non-cooked seeds of the same transgenic line. The variable segregation pattern in T1 selfing generation indicated single to multiple loci insertion of the transgenes in the genome. This is the first report of using nonantibiotic pmi driven by a novel promoter in generating transgenic indica rice for possible future use in human nutrition. 相似文献
335.
Nyporko A. Yu. Yemets A. I. Klimkina L. A. Blume Ya. B. 《Russian Journal of Plant Physiology》2002,49(3):413-418
The sensitivity of calluses derived from susceptible and resistant goosegrass (Eleusine indica (L.) Gaertn.) biotypes to dinitroaniline herbicides, which disrupt interphase and mitotic-spindle microtubules, was evaluated. A callus culture derived from the resistant biotype retained resistance to both trifluralin (dinitroaniline herbicide) and amiprophosmethyl (phosphorothioamidate herbicide). The site for the interaction between -tubulin subunit and dinitroaniline or phosphorothioamidate herbicides was identified by computer simulation. A correlation was found between the level of callus sensitivity to herbicide tested and the pattern of herbicide interaction with -tubulin. 相似文献
336.
? Premise of the study: Accurate and reliable predictive models are necessary to estimate nondestructively key variables for plant growth studies such as leaf area and leaf, stem, and total biomass. Predictive models are lacking at the current-year branch scale despite the importance of this scale in plant science. ? Methods: We calibrated allometric models to estimate leaf area and stem and branch (leaves + stem) mass of current-year branches, i.e., branches several months old studied at the end of the vegetative growth season, of four mango cultivars on the basis of their basal cross-sectional area. The effects of year, site, and cultivar were tested. Models were validated with independent data and prediction accuracy was evaluated with the appropriate statistics. ? Key results: Models revealed a positive allometry between dependent and independent variables, whose y-intercept but not the slope, was affected by the cultivar. The effects of year and site were negligible. For each branch characteristic, cultivar-specific models were more accurate than common models built with pooled data from the four cultivars. Prediction quality was satisfactory but with data dispersion around the models, particularly for large values. ? Conclusions: Leaf area and stem and branch mass of mango current-year branches could be satisfactorily estimated on the basis of branch basal cross-sectional area with cultivar-specific allometric models. The results suggested that, in addition to the heteroscedastic behavior of the variables studied, model accuracy was probably related to the functional plasticity of branches in relation to the light environment and/or to the number of growth units composing the branches. 相似文献
337.
芒果叶化学成分研究 II 总被引:1,自引:0,他引:1
为探讨芒果(Mangifera indica L.)的化学成分,从芒果叶的70%乙醇提取物中分离鉴定了13个化合物,经波谱分析,分别鉴定为:(–)-secoisolariciresinol-9′-O-D-glucopyranoside(1)、7S,8R-erythro-4,7,9-trihydroxy-3,3′-dimethoxy-8-O-4′-neolignan-9′-O-β-D-glucopyranoside(2)、7R,8R-threo-4,7,9-trihydroxy-3,3′-dimethoxy-8-O-4′-neolignan-9′-O-β-D-glucopyranoside(3)、(7R/S,8R)-7,8-dihydro-9′-hydroxyl-3′-methoxyl-8-hydroxymethyl-7-(4-hydroxy-3-methoxyphenyl)-1′-benzofuranpropanol 9′-O-β-D-glucopyranoside(4)、citrusin D(5)、丁香苷(6)、2,6-二甲氧基-4-羟基苯基-1-O-β-D-葡萄糖苷(7)、原儿茶酸(8)、没食子酸(9)、没食子酸甲酯(10)、没食子酸乙酯(11)、4,5-二羟基-3-甲氧基苯甲酸(12)、β-胡萝卜苷(13)。其中化合物1~7和12为首次从芒果属植物中分离得到。 相似文献
338.
目的:观察合萌水提物的抗炎、镇痛作用。方法:采用二甲苯致小鼠耳肿胀、角叉菜胶致小鼠足跖肿胀、醋酸致小鼠腹腔毛细血管通透性增加及醋酸致小鼠扭体实验、热板实验模型,观察合萌水提物的抗炎镇痛作用,并测定丙二醛(MDA)、一氧化氮(NO)的含量及超氧化物歧化酶(SOD)活性。结果:合萌水提物可抑制二甲苯致小鼠耳肿胀,减轻小鼠足跖肿胀,降低小鼠毛细血管通透性,减少醋酸致小鼠扭体次数,增加热板小鼠痛阈值,降低血清MDA、NO含量,提高血清SOD活性。结论:合萌水提物具有抗炎镇痛作用,作用机制可能与降低血管通透性、抑制NO等炎症介质产生及增强清除自由基、抗脂质过氧化能力有关。 相似文献
339.
340.
Pinus elliottii is an exotic afforestation pine extensively distributed in
southern parts of China. In order to understand whether endophytic fungi can
affect seedling growth of P. elliottii, Piriformospora indica (Pi), Funnelifcrmis
mosseae (Fm), and Diversispora tortuosa (Dt) were inoculated respectively,
and the non-inoculated group was set as control. The growth indexes, the contents
of soluble sugar and soluble protein, and plant endogenous hormone levels in the
leaves of P. elliottii, were analyzed. The results showed that Fm, Dt and Pi colonized
the P. elliottii roots to form mycorrhizal structure and chlamydospores
arranged in beads respectively. Three fungal inoculants exhibited the stimulated
growth responses, whilst Dt illustrated the most positive effect on plant height, single
fresh weight, trunk diameter and root system structure, compared with the control.
On the other hand, the soluble sugar and soluble protein contents were
increased distinctively in mycorrhizal plants. The endogenous IAA, GA3, ZR contents
were increased, while the ABA contents were reduced in mycorrhizal plants
versus non-mycorrhizal plants. The fungi-induced endogenous hormone changes
triggered plant growth improvement of P. elliottii seedlings. This research unraveled
the positive effect of AM fungi and P. indica on growth of pine seedlings, while,
more application of endophytic fungi to fields needs to be explored. 相似文献