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31.
A method for rapid in vitro propagation of Cassia siamea Lam. using cotyledonary node explants, excised from 14-day old aseptic seedlings, has been established. Murashige and Skoog
(MS) medium supplemented with different concentrations of 6-benzyladenine (BA), kinetin (Kn) and thidiazuron (TDZ) singly
or in combination with auxins was used for regeneration studies. Among the single treatment of three cytokinins BA at 1.0 μM
was found to be optimum for direct shoot regeneration as it induced an average of 8.20 ± 0.66 shoots per explant. The regeneration
frequency further enhanced with the application of auxin along with optimal BA concentration. The highest frequency for shoot
regeneration (90%), the maximum number of shoots per explant (12.20 ± 0.73) and the maximum shoot length (6.40 ± 0.07) cm
were obtained on the medium consisted of MS + 1.0 μM BA + 0.5 μM NAA. Successful in vitro rooting was induced from cut end
of the microshoots when placed on half-strength MS + IBA (2.5 μM). The regenerated shoots with well developed root system
were successfully acclimatized and established in pots containing sterilized garden soil and garden manure (1:1) and grown
under greenhouse conditions with 85% survival rate. 相似文献
32.
33.
全球变暖大背景下,塔里木盆地边缘绿洲气候变化趋势研究已成为研究的热点。文中利用塔里木盆地南、北缘17个典型绿洲气象站1959-2008年的气象资料,使用联合国粮农组织(FAO)推荐的Penman-Monteith公式,计算近50年潜在蒸散量,定义了地表干燥度指数。在此基础上,对塔里木盆地南、北缘,近50年气候变化特征及其成因进行对比分析。结果表明:塔里木盆地南、北缘气候变化与全球气候变化趋势基本一致,但又具有明显的区域性特点:塔里木盆地南、北缘潜在蒸散量均在波动中呈减少趋势,南缘递减速度比北缘快;干燥度指数也均在波动中呈缓慢减小趋势,其中南缘干燥度指数递减速度比北缘快;总之塔里木盆地南、北缘绿洲有缓慢向暖湿转化的迹象,这对气候极端干燥的塔里木盆地边缘绿洲生态环境的改善和农业生产有积极的影响。 相似文献
34.
Hongyan?Yu Weixin?DingEmail author Jiafa?Luo Ruilin?Geng Anwar?Ghani Zucong?Cai 《Biology and Fertility of Soils》2012,48(3):325-336
The study examined the influence of compost and mineral fertilizer application on the content and stability of soil organic
carbon (SOC). Soil samples collected from a long-term field experiment were separated into macroaggregate, microaggregate,
and silt + clay fractions by wet-sieving. The experiment involved seven treatments: compost, half-compost N plus half-fertilizer
N, fertilizer NPK, fertilizer NP, fertilizer NK, fertilizer PK, and control. The 18-year application of compost increased
SOC by 70.7–121.7%, and mineral fertilizer increased by 5.4–25.5%, with no significant difference between control soil and
initial soil. The C mineralization rate (rate per unit dry mass) in microaggregates was 1.52–2.87 mg C kg−1 day−1, significantly lower than in macroaggregate and silt + clay fractions (P < 0.05). Specific C mineralization rate (rate per unit SOC) in silt + clay fraction amounted to 0.48–0.87 mg C g−1 SOC day−1 and was higher than in macroaggregates and microaggregates. Our data indicate that SOC in microaggregates is more stable
than in macroaggregate and silt + clay fractions. Compost and mineral fertilizer application increased C mineralization rate
in all aggregates compared with control. However, compost application significantly decreased specific C mineralization rate
in microaggregate and silt + clay fractions by 2.6–28.2% and 21.9–25.0%, respectively (P < 0.05). By contrast, fertilizer NPK application did not affect specific C mineralization rate in microaggregates but significantly
increased that in silt + clay fractions. Carbon sequestration in compost-amended soil was therefore due to improving SOC stability
in microaggregate and silt + clay fractions. In contrast, fertilizer NPK application enhanced SOC with low stability in macroaggregate
and silt + clay fractions. 相似文献
35.
Contamination of metal ions in soil and water represents more pressing threats to resources as well as human health. The present research was carried out to screen the phytosequester plants growing in industrial waste- and wastewater-affected industrial areas of Okhla, New Delhi, India. Accumulation trend of metal Fe, Zn, Cu, Cr, Pb, Cd, Hg, and As from soil and wastewater by plants were collected for study. Among aquatic plants Hydrilla verticillata, Marsilea quadrifolia, and Ipomea aquatica were found to be highest metals accumulator, Eclipta alba and Sesbania cannabina among terrestrial plant were highest accumulator of metals. Among the algal spp. Spirulina platensis and Phormidium papyraceum were the most efficient in accumulating Cd and Hg. The maximum bioconcentration factor (BCF) was recorded in Hygroryza aristata for the metals (Hg, Cd) in M. quadrifolia (Cd, Cr), in E. alba (Cr, Cu), and in S. platensis (Hg, Pb). However, the translocation factor (TF) of metals was found more in M. quadrifolia followed by I. aquatica than other plants. Among all the plants, H. verticillata showed high TF and low BCF values for toxic metals (Pb, Cr) and was suitable for phytostabilization of these metals. Our study showed that native plant species growing on contaminated sites may have a potential of phytosequestration of these metals. 相似文献
36.
2006年8月和12月,在新疆车尔臣河下游阿克塔孜牧场,对塔里木马鹿夏季和冬季生境的选择进行了研究。选择5类生态因子,并设置290个10 m×10 m样方。选择结果表明,塔里木马鹿喜欢胡杨和芦苇、植被覆盖度较大、水源距离较近和认为干扰距离>1 000 m的环境。其中,夏季多选择芦苇草甸,冬季选择胡杨林和柽柳灌丛。对生境特征的主成分分析显示,前3个主成分的累计贡献率夏季达到71.277%,冬季达到67.925%,可以反映塔里木马鹿的生境特征。同时表明,影响塔里木马鹿生境选择的主要因素依次为人为干扰、植被类型和距水源距离。 相似文献
37.
U.M.K.Anwar M.T.Paridah 《世界竹藤通讯》2008,(3):48-48
本文研究了用低分子酚醛树脂(LMWPF)浸渍竹篾(巨草竹属)。竹子样品是竹秆的基部和中部。采用真空法.用低分子酚醛树脂处理竹篾后,评估处理后的竹篾增重率加湿含率。竹篾浸渍在树脂增加的时间越长,其增重率就越高。浸渍120min后,基部和中部的增重率分别提高了4.51%和7.52%。 相似文献
38.
Jingjuan Zhang MD Shahidul Islam Yun Zhao Masood Anwar Zaid Alhabbar Maoyun She Rongchang Yang Angela Juhasz Guixiang Tang Jiansheng Chen Hang Liu Yanjie Jiang Shengnan Zhai Xin Hu Junkang Rong Yingquan Zhang Yebo Qin Qier Liu Zitong Yu Yujuan Zhang Sadegh Balotf Mirza Dowla Sonia Afrin Nandita Roy Md Resad Mallik Md Atik Us Saieed Shanjida Rahman Nigarin Sultana Sarah Al-Sheikh Ahmed Chris Florides Kefei Chen Darshan Sharma Nathan Height Ben Biddulph Meiqin Lu Jorge EMayer Wujun Ma 《作物学报(英文版)》2022,(1):147-165
Reproductive stage frost poses a major constraint for wheat production in countries such as Australia.However,little progress has been made in identifying key genes to overcome the constraint.In the present study,a severe frost event hit two large-scale field trials consisting of six doubled haploid(DH)wheat populations at reproductive stage(young microspore stage)in Western Australia,leading to the identification of 30 robust frost QTL on 17 chromosomes.The major 18 QTL with the phenotype variation over 9.5%were located on 13 chromosomes including 2 A,2 B,2 D,3 A,4 A,4 B,4 D,5 A,5 D,6 D,7 A,7 B and7 D.Most frost QTL were closely linked to the QTL of anthesis,maturity,Zadok stages as well as linked to anthesis related genes.Out of those,six QTL were repetitively detected on the homologous regions on 2 B,4 B,4 D,5 A,5 D,7 A in more than two populations.Results showed that the frost damage is associated with alleles of Vrn-A1 a,Vrn-D1 a,Rht-B1 b,Rht-D1 b,and the high copy number of Ppd-B1.However,anthesis QTL and anthesis related genes of Vrn-B1 a and Ta FT3-1 B on chromosomes 5 B and 1 B did not lead to frost damage,indicating that these early-flowering phenotype related genes are compatible with frost tolerance and thus can be utilised in breeding.Our results also indicate that wild-type alleles Rht-B1 a and Rht-D1 a can be used when breeding for frost-tolerant varieties without delaying flowering time. 相似文献
39.
Faqir Muhammad Masood Akhtar M. Irfan Anwar M. Javed Arshed 《Veterinary research communications》2009,33(8):971-977
Ciprofloxacin was administered intravenously @ 5 mg/kg body weight to six healthy dogs. After a washout period of two weeks,
fever was induced by injecting Escherichia (E) coli endotoxin. Ciprofloxacin was administered again. Blood samples were collected at various time intervals and analyzed for
ciprofloxacin with HPLC. The kinetic analysis revealed the volume of distribution in healthy vs. febrile dogs as 2.12 ± 0.32
vs. 1.79 ± 0.43 L/Kg, respectively. The elimination half life was 2.23 ± 0.78 and 2.07 ± 0.74 hours in healthy and febrile
dogs, respectively. Similarly, dogs under healthy and febrile conditions showed comparable total plasma clearance of 0.66 ± 0.06
and 0.60 ± 0.07 L/Kg/h, respectively. All these and other investigated kinetic parameters were statistically non significant.
This study concludes that the pharmacokinetic behavior of ciprofloxacin is similar under healthy and febrile conditions. Thus,
the kinetic studies of fluoroquinolones conducted in normal/healthy animals may be used to depict the pharmacokinetic parameters
in diseased animals. 相似文献
40.
Md. Taslim Anwar Athar Imam Khan Sivasankaran Balasubramanian Ramamurthy Jayaprakash Thandavan A. Kannan Sakthivel Manokaran Sathiamangalam A. Asokan Chitravelan Veerapandian 《The Canadian veterinary journal. La revue veterinaire canadienne》2009,50(8):854-856
We present a case of globosus amorphus delivered from a goat and subjected to radiography and histological examination. Radiography revealed a lack of development of any organ system; histological sections showed evidence of lymphoid aggregations, mononuclear infiltrations, blood capillaries, and dense fibroblasts. 相似文献