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51.
Sanjay K. Sharma Ankita Sharma Surinder Rana Naveen Kumar 《Journal of plant nutrition》2018,41(6):782-792
Sixty soil samples (0–0.15 m depth) collected randomly from different districts of Himachal Pradesh were used to evaluate ammonium bicarbonate-diethylenetriaminepenta acetic acid (AB-DTPA) and acid ammonium acetate-ethylene diamine tetra acetic acid (AAAc-EDTA) over standard methods for P, K, and micronutrient cations. Among Olsen P, Bray P1, AB-DTPA P, and AAAc-EDTA P, available P (kg ha?1) varied from 7.8 to 44.3, 9.5 to 61.1, 6.5 to 38.8, 10.5 to 52.1; available K (kg ha?1) among NH4OAc, AB-DTPA, and AAAc-EDTA ranged from 103.6 to 372.3, 86.6 to 364.9, and 74.6 to 362.5. In case of micronutrients cations, AB-DTPA in general, extracted more amounts as compared to DTPA alone. AAAc-EDTA correlated highly with the Olsen P. AB-DTPA-K and AAAc-EDTA-K correlated well with standard method (NH4OAc) however; AAAc-EDTA had higher correlation with AB-DTPA for K extractability. Among methods for micronutrients highest significant correlations were observed between AB-DTPA and DTPA for Cu, Fe, and Zn. 相似文献
52.
One of the major applications of plant tissue culture technology is that the regenerants are genetically identical to the
mother plant. Although, of the various methods of in vitro propagation, axillary branching method is regarded as the safest,
the possibility of genetic variation (somaclonal variation) cannot be ruled out even in this method. In the present study,
inter simple sequence repeat (ISSR) marker assay was employed to validate the clonal fidelity of in vitro raised Bambusa balcooa plantlets multiplied by enhanced axillary proliferation up to 33 passages. Fifteen ISSR primers generated a total of 99 amplicons
among the tissue-cultured progenies. Analysis of ISSR patterns revealed that the bands were shared by both the parent clump
and the in vitro raised plants confirming the genetic stability in the latter. 相似文献
53.
Arun Prasad Sanjay Kumar Abdul Khaliq Ankit Pandey 《Biology and Fertility of Soils》2011,47(8):853-861
The effects of increasing levels of metals (10 and 20 mg of Cr kg-1 and 25 and 50 mg of Cd, Pb, and Ni kg-1 soil) and arbuscular mycorrhizal (AM) fungi Glomus intraradices on the yield, chemical composition of volatile oil, and metal accumulation in sweet basil (Ocimum basilicum L.) were investigated in a pot experiment. The shoot yield, content of essential oil, and root yield of sweet basil were
increased by the application of low dose of Cd, Pb, and Ni as compared to control. The application of high level of metals
had deleterious effect on the yield. In soil with low dose of metal applied, AM fungi inoculation significantly enhanced the
metal concentration in shoots and had adverse effect on the yield, whereas in soil with high dose of metal applied, AM fungal
inoculation reduced the metal concentration in shoot and had beneficial effect on the yield. The content of linalool in basil
oil was decreased and that of methyl chavicol was increased by the application of Cr, Cd, and Pb in soil as compared to control.
Similarly, the level of linalool and methyl chavicol was decreased and that of methyl eugenol was increased by the application
of Ni as compared to control. However, AM fungal inoculation led to maintain the content of linalool, methyl chavicol, and
methyl eugenol in volatile oil, which were either increased or decreased by the application of metals. We conclude that the
AM–sweet basil symbiosis could be used as a novel approach to enhance the yield and maintain the quality of volatile oil of
sweet basil under metal-contaminated soils. 相似文献
54.
Sanjay Kapil Teresa Yeary Bill Johnson 《Veterinary Clinics of North America: Small Animal Practice》2008,38(4):755-74, vii
In this article, the authors are specifically concerned with the timely and accurate detection of emerging diseases of small animals that are viral in origin. Veterinarians are bound to encounter emerging viruses in their practice. The problem is unavoidable, because viruses are highly mutagenic. Even the immune response dictates the nature of virus that evolves in a host. If the clinical signs and diagnostic methods fail to correlate, the veterinarian should work with the diagnostic laboratory to solve the diagnostic puzzle. 相似文献
55.
Kharayat Nitish Singh Sharma G Chethan Kumar Gandham Ravi Bisht Deepika Chaudhary Gangaram Singh Sanjay Kumar Das Gautum Kumar Garg Anil Kumar Kumar Harendra Krishnaswamy Narayanan 《Veterinary research communications》2019,43(4):261-269
Veterinary Research Communications - Toll like receptors (TLRs) and β-defensins expressed in the endometrium are part of the innate uterine defense mechanism (UDM). In the present study,... 相似文献
56.
Stuart Meier Chris Gehring Cameron Ross MacPherson Mandeep Kaur Monique Maqungo Sheela Reuben Samson Muyanga Ming-Der Shih Fu-Jin Wei Samart Wanchana Ramil Mauleon Aleksandar Radovanovic Richard Bruskiewich Tsuyoshi Tanaka Bijayalaxmi Mohanty Takeshi Itoh Rod Wing Takashi Gojobori Takuji Sasaki Sanjay Swarup Yue-ie Hsing Vladimir B. Bajic 《Rice》2008,1(2):177-187
57.
The population structure of tree species has been explored in order to elucidate regeneration potential of the subalpine forests of Indian western Himalaya. For this study, the subalpine forest area was divided into three strata, i.e., lower altitude (〈3000 m); mid-altitude (3000-3200 m); and high altitude (〉3200m). Considering the major compositional attributes, an increase in altitude came with a significant decline in tree density and the total basal area for all the sites. However, no such clear trends were observed for recruits (i.e., seedlings and saplings). Seedling density did not exhibit uniform patterns for sites and altitude strata. In general, overall seedling density was greater at the Pindari site compared to the Lata and Tungnath sites. By comparison, significant variation in seedling density along the altitude strata was recorded for the Tungnath and Pindari sites only. Likewise, sapling density patterns varied across the sites and altitude strata, and significant variation in sapling density along the altitude strata was recorded only for the Lata site. At the Pin- daft site, the continuous increase in sapling density along with increasing altitude was revealing. The Pindari forests of exhibited expanding population structure. In contrast, greater accumulation of individuals in the sapling class and sharp decline toward both higher tree classes and lower seedling classes was generally apparent for the Lata and Tungnath sites. This indicates that the replacement in tree size classes from sapling stage is not proportional and the population may decline in the long-term. Considerable variation in patterns of forest and dominant species popula- tion structure were evident across altitude strata. But in all cases irrespective of sites, we found growth at the high-altitude stratum, in the form of entire forests or dominant species. This trend deserves further investigation to explore its relevance under changing climate scenarios. 相似文献
58.
Dietary pyridoxine promotes growth and cellular metabolic plasticity of Chanos chanos fingerlings exposed to endosulfan induced stress 下载免费PDF全文
Neeraj Kumar Kondusamy Ambasankar Kishore Kumar Krishnani Sanjay Kumar Gupta Paramjit Singh Minhas 《Aquaculture Research》2017,48(5):2074-2087
An attempt was made to assess the effect of dietary pyridoxine supplementation on growth performance and cellular metabolic enzymes of Chanos chanos fingerlings under endosulfan induced stress. Two‐hundred and twenty‐five fish were randomly distributed into five treatments, each with three replicates and fed four isocaloric and isonitrogenous diets with graded levels of pyridoxine for 45 days. Endosulfan concentration in the water was maintained at sublethal level of 1/40th of 96 h LC50 (0.52 ppb). Dietary pyridoxine supplementation significantly enhanced growth performance viz. weight gain (%), specific growth rate, feed conversion ratio and protein efficiency ratio of fish compared to control diet fed group. The results of this experiment revealed that the activities of digestive and metabolic enzymes were significantly improved after feeding with dietary pyridoxine supplementation in C. chanos. Significantly increased muscle and brain ascorbic acid content was observed in fish fed diets containing pyridoxine. Histological studies on liver of fish fed pyridoxine‐supplemented diet showed the normal architecture of hepatocytes compared to non‐pyridoxine fed group. The results obtained in this study revealed that the inclusion of pyridoxine in diet has a protective effect against endosulfan induced stress in C. chanos fingerlings through metabolic enzyme activities and vitamin C content. This study has a potential in ameliorating the toxic effect of endosulfan induced stress using dietary supplementation of pyridoxine. 相似文献
59.
Morphology and general characteristics of phages specific to Lens culinaris rhizobia 总被引:1,自引:0,他引:1
Four lytic phages, namely LRP-1, LRP-4, LRP-13, and LRP-15, active against indigenous rhizobial strains of Lens culinaris were isolated and characterized for their individual morphology, host range, plaque characteristics, lytic behavior, and
restriction endonuclease profiling of phage DNA. All phages had a typical polyhedral head and long non-contractile tail, representing
the bacteriophage family close to Siphoviridae. Phages produced distinct types of plaques on their indicator bacterial strains. The host range of the phage isolates was
restricted to Rhizobium leguminosarum biovars and no cross infectivity among susceptible strains was observed. A study on the lytic cycle of the phages under identical
conditions exhibited distinct latent period and burst size. Inactivation pattern of phages with temperature and UV light was
quite distinct. Phage LRP-1 showed higher thermal resistance, though greater sensitivity to UV light, as compared to other
phages. Genome sizes of the phages were estimated to vary between 50–72 kbp. The 16S rRNA sequence analysis of the phage indicator
rhizobial strains revealed 81% to 100% similarity with R. leguminosarum bv. viciae. The phages could thus prove to be considerably useful in typing and investigating into the genetic variability which might
exist amongst the soil rhizobia nodulating Lens culinaris. 相似文献
60.
Alpana Kulhari Arun Sheorayan Sanjay Kalia Ashok Chaudhury Rajwant K. Kalia 《Genetic Resources and Crop Evolution》2012,59(6):1223-1254
Commiphora wightii (Arn.) Bhandari syn. C. mukul Engl. (Burseraceae) is an economically and pharmacologically important slow growing, dioecious, balsamiferous woody, multipurpose shrub heading towards extinction. Commonly known as “Guggul” due to the presence of steroidal compound guggulsterone in the oleo-gum resin, it has been used in treating various ailments and disorders since ancient times (2000 B.C.). Evaluation and confirmation of hypolipidemic effects of guggul based on Ayurvedic text in 1960s provided a new insight into its pharmacological applications. Two bioactive isomers of guggulsterone, E and Z, are responsible for lipid- and cholesterol-lowering activities. Recently, it has been shown to have anti-cancerous activity also. It is found in the dry regions of Indian subcontinent, namely India, Pakistan and Bangladesh. Ruthless and unscientific harvesting of oleo-gum resin from the wild, by local populations, for economic benefits with negligible conservation efforts has made this species endangered and has led to its inclusion in Red Data Book of IUCN. Although this plant has many excellent traits, adequate attention has not been focused on its conservation and improvement. Conventional propagation methods i.e., seeds, cuttings and air layering are in place but have many limitations. Therefore, application of modern biotechnological tools needs to be standardized for harnessing maximum benefits from this pharmaceutically important plant. An efficient regeneration system needs to be in place for improvement of this genus through genetic transformation and production of useful metabolites in cell cultures. Studies are in progress for micropropagation through shoot multiplication and somatic embryogenesis, as well as for secondary metabolite (guggulsterone) production in callus cultures and bioreactors. No selected germplasm is available for C. wightii since it is a wild plant. Breeding programs have not yet been started due to lack of systematic cultivation and conservation programs. Moreover, little information has been gathered regarding the genetic variability in this species using RAPD and ISSR markers. No details are available about genetic makeup and QTL linkage maps. Investigations are in progress to search sex linked markers in this dioecious species. Research is also in progress to decipher the molecular mechanisms underlying various pharmacological actions of guggul. Since the approval of use of guggul as a food supplement by United States Food and Drug Administration in 1994, an exponential increase in research publications on various aspects of research on guggul have been published. Present communication summarizes the problems, progress made and suggests some future directions of research for this important endangered medicinal plant. 相似文献