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排序方式: 共有116条查询结果,搜索用时 15 毫秒
41.
Neeraj Choudhary Asma Hamid Bikram Singh Irshad Khandy Parvaze A. Sofi Mohd Ashraf Bhat Reyazul Rouf Mir 《Genetic Resources and Crop Evolution》2018,65(3):963-977
Common bean (Phaseolus vulgaris L.) is considered as one of the principal grain legume crops grown in north-western Himalayan state of Jammu and Kashmir (J&K), India. Huge diversity has been observed for this crop in state Jammu and Kashmir. The hilly regions of the state J&K are famous for producing high quality, tasty and highly flavoured beans. In order to characterise this huge diversity and trace the origin of common bean, systematic efforts have been made for the first time in collection, evaluation and characterization of bean collection from Jammu & Kashmir. A set of 428 common bean lines were initially collected/procured and based on cluster analysis using few qualitative traits/site of collection, a diverse set of 96 lines was selected. The PCR assay for phaseolin locus led to the characterization of 96 lines into Meso-american and Andean types. Out of 96 lines tested, 45 possessed “S” type phaseolin and 51 possess “T” type phaseolin. The ITS region of selected local and exotic lines was Sanger sequenced and the sequence analysis of ~ 800 bp long region revealed the presence of 12 SNPs including one promising SNPs showing significant association with phaseolin patterns. The clustering based on ITS sequence data led to the clear cut separation of common bean lines into two distinct clusters based on their phaseolin types. The results of the present study helped to gain insights into the origin of common bean landraces grown in state of J&K, India. 相似文献
42.
Parthenium hysterophorus (Asteraceae) is known as one of the most aggressive invasive weeds, causing severe economic, environmental, human and animal health problems in India and around the world. During a series of extensive surveys for natural enemies of P. hysterophorus, a leaf spot pathogen was isolated from the affected parts of the parthenium following the standard isolation techniques using potato dextrose agar (PDA) and parthenium dextrose agar (PeDA) media. Koch's postulates were performed and found satisfactory for the isolate and proved to be pathogenic to this weed. On the basis of cultural, morphological and molecular characteristics, the pathogen was identified as Alternaria sp. PMK2. The growth of the pathogen was studied on eight selected media and it exhibited varying degrees of growth on different media. Phytotoxicity of fungal cultural filtrates was also confirmed on parthenium leaves in laboratory conditions. Due to the virulent nature of the isolated pathogen, it may be selected for further studies to develop mycoherbicide for control of this devastating weed. 相似文献
43.
Dibya Joshi Rama Dwivedi Satya P. Pachauri Arvind K. Shukla 《Communications in Soil Science and Plant Analysis》2017,48(8):886-897
Twenty surface (0–15 cm) samples of acidic soils were analyzed for water soluble (WS), exchangeable (EX), lead displaceable (Pb-disp.), acid soluble (AS), manganese (Mn) oxide occluded (MnOX), organically bound (OB), amorphous Fe oxide occluded (AFeOX), crystalline iron (Fe) oxide occluded (CFeOX) and residual (RES) fractions of Mn, and also for extractable Mn in some common soil extractants: (diethylenetriaminepentaacetic acid (DTPA) (pH 7.3), DTPA (pH 5.3), AB-DTPA (pH 7.6), Mehlich-3 (pH 2.0), Modified Olsen, 0.005 M calcium chloride (CaCl2), 1 M magnesium chloride (MgCl2) and ion exchange resins. The WS-Mn fraction showed a significant and positive correlation with Mn extractable in DTPA (pH 5.3) and AB-DTPA (pH 7.6), while both WS-Mn and EX-Mn fractions correlated significantly and positively with Mn concentration and uptake by maize plants grown in these soils. The AB-DTPA (pH 7.6) and DTPA (pH 5.3) appeared suitable to assess the availability of Mn in acidic soils. 相似文献
44.
S. L. Agrawal Markandey Singh Mrigank Mauli Dwivedi Kamlesh Pandey 《Fibers and Polymers》2011,12(7):864-874
Present paper deals with, improvement in ion transport property and dielectric relaxation of polyethylene oxide (PEO)-based
polymer electrolytes subsequent to dispersal of nanosized Zn-ferrite filler particles. The nanocomposite polymer electrolyte
(NCPE) system [93PEO:7NH4SCN]: x% Zn-ferrite was prepared by solution cast technique through dispersal of sol gel derived Zn-ferrite nano powder in
the pristine polymer electrolyte solution. The structural and morphological behavior of NCPEs have been studied by XRD, SEM,
IR and DSC measurements. Electrical conductivity (both a.c. & d.c.) measurement on nanocomposite polymer electrolyte sample
have been carried out using impedance spectroscopic technique. Dielectric relaxation studies were extracted by impedance data.
The hopping ion transport mechanism in NCPEs has been concluded with the help of dielectric and modulus formalism. 相似文献
45.
利用卫星遥感和GIS技术测定印度切蒂斯格尔地区干旱热带森林的土地利用、生物量和碳贮量 总被引:1,自引:0,他引:1
Arvind Bijalwan S.L.Swamy Chandra Mohan Sharma Neeraj Kumar Sharma A.K.Tiwari 《林业研究》2010,21(2):161-170
2001-2002年间,利用卫星遥感和GIS技术研究印度切蒂斯格尔邦的赖布尔地区干旱热带森林的土地利用、生物量和碳贮量情况。主要森林类型为:柚木森林、混合林、衰退森林和婆罗双树混交林。在这些不同森林类型中,立地的坡度和坡面影响森林植被类型、生物量和碳贮量。不同森林类型中,木材积蓄积量、生物量和碳贮量的变化范围分别为:35.59~64.31 m3·hm-2、45.94~78.31Mg·hm-2和22.97~33.27Mg·hm-2。混合林中每公顷的木材蓄积量、生物量和碳贮量最大,衰退森林中的最低。混合林、柚木森林、衰退森林和婆罗双树混交林的总碳量分别为8170.72 Mg、81656.91 Mg、7833.23 Mg和7470.45 Mg。蒂斯格尔邦地区干旱热带森林处于不成熟的生长阶段,且具有很强的碳回收潜力。图6表7参49。 相似文献
46.
47.
Agro-morphological characterization of ovary culture-derived plants of rice (Oryza sativa L.) 总被引:2,自引:0,他引:2
Plants derived from unpollinated ovary culture of ten rice genotypes showed significant variability in agro-morphological
characteristics. The ovary-derived plant (H1) populations were completely haploid, doubled haploid or haploid-doubled haploid
mixture. Haploids had very drastic reduction in plant height, panicle length, grain length, breadth and number and spikelet
fertility (0.0%–2.1%). Doubled haploids from the hybrid of UPRI 95–121 × UPRI 95–165 were normal with fertility ranging between
69.6% and 97.7%. A genetic segregation in ratio of 1:1 was observed for five pigmentation characters in the H1 population
derived from hybrid UPRI 95–122 × UPRI 95–165. Plant height showed the largest coefficient of variability (28.5%) followed
by the number of spikelets per panicle (24.2%), number of grains per panicle (22.0%), percent seed set (9.2%) and panicle
length (9.0%). The range of variation in the H1 population from fully fertile hybrid PMS 2A (CMS) × IR 31802 (restorer) was
similar to its corresponding F2 population for plant height, spikelet fertility and number of grains/panicle. A single clone
of plants from the cultivar BG 1321 exhibited complete male sterility but normal female fertility when pollinated with other
varieties. Ovary-derived plants from the CMS lines PMS 2A and IR 58025A showed stable male sterility and those from thermosensitive
genetic male sterile line UPRI 95–140 showed thermosensitive genetic male sterility. These lines have potential in the hybrid
breeding program and are being currently exploited.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
48.
R. S. Dwivedi 《Land Degradation \u0026amp; Development》1994,5(3):191-199
Salinization/alkalization and waterlogging have rendered a sizeable area of India's arable lands unproductive. These highly dynamic phenomena can be studied using remote sensing data collected at regular intervals. Landsat Multi-spectral Scanner data of 28 February 1975 and 9 March 1990 were interpreted visually to derive information about the spatial extent and distribution of salt-affected soils. A significant decrease in the area of salt-affected soils was noted over this period, which can be attributed to reclamation efforts by government agencies and farmers. On a large scale, i.e. 1:50000, the waterlogged area could also be mapped using a Landsat Thematic Mapper false-colour composite print. 相似文献
49.
Fusarium oxysporum and Fusarium solani are the two most destructive pathogens causing wilt disease in guava (Psidium guajava L.) commonly known as ‘super fruits’. These pathogens attack mainly on the root region of the plant and cause severe infection. In the present investigation the infection process was studied with scanning electron microscopy (SEM) and it was observed that the root region of the guava plant showed disintegration and necrosis in the epidermal layer, cortex tissue, and in vascular bundles, while the root region of a healthy sapling showed no such changes. The rupturing of the epidermal layer may show the entry of pathogens in the host tissue through the secretion of toxic enzymes/metabolites. These toxins have great potential to cause wilting symptoms in guava plants in the form of necrosis. Wilt disease causes huge losses in guava production in both tropical and subtropical countries. Therefore, there is a need to find the responsible factors. The present study is an attempt to understand the interaction mechanism of phyto-pathogens causing wilt disease. 相似文献
50.