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1.
The present study deals with root architecture of 6-year-old trees of 9 indigenous and 3 exotic species growing in arid climate of north-western India. Observations, made on excavated root systems (3 tree replicates of each species) showed large variation in horizontal and vertical spread of roots. In Morus alba, Melia azedarach and Populus deltoides, the roots were confined to 80 cm, while in Prosopis cineraria, Acacia nilotica and Eucalyptus tereticornis, roots penetrated more deeply to 233 cm. The number of total roots ranged from 103 in Acacia catechu to 1932 in Eucalyptus tereticornis, and 62 to 80% of the roots were less than 2 mm in diameter. The primary roots were more horizontal than the secondary roots. The total root biomass varied from 2.2 kg in Acacia catechu to 30.6 kg–1 tree in Populus deltoides, and top 30 cm soil contained 42 to 78% of the total biomass. The implications of the results are discussed in the context of the ecological niche of the species, and its usefulness in agroforestry systems. 相似文献
2.
Prosopis cineraria is an important species for aridzone agroforestry in India. Information on the chemical composition and nutritive value of the leaves of young trees that will be useful in screening the provenances, is lacking. Chemical composition (N, P, K, Ca, Mg, Na), crude protein, and structural carbohydrates (neutral detergent fibre, acid detergent fibre, cellulose, hemicellulose, and lignin) of the foliage of one-year-old plants of 31 provenances ofProsopis cineraria were determined. The seeds were collected from 16°50 N to 29°55 N latitude and 69°49 E to 78°03 E longitude in India, and grown at Hisar (29°10 N latitude, 75°46 E longitude and 215 m altitude). Mineral contents (except N and P), crude protein, and structural carbohydrates varied significantly (p<0.05) between provenances, and the greatest amount of N, P, crude protein, NDF, ADF and lignin contents were found in Hisar provenance. The in vitro dry matter digestibility varied from 18.2% in Gandhinagar provenance to 34.0% in that of Barmer provenance. 相似文献
3.
Effects of Addition of Tissue‐Type Plasminogen Activator in In Vitro Fertilization Medium on Bovine Embryo Development and Quality 下载免费PDF全文
F Krania E Dovolou CA Rekkas EK Theodosiadou I Pappas GS Amiridis 《Reproduction in domestic animals》2015,50(1):112-120
Plasminogen activators/Plasmin system plays pivotal role in regulating reproductive functions of mammals. Here, we examined the effects of modification of in vitro fertilization medium (IVF medium) with the addition of tissue‐type plasminogen activator (t‐PA), on bovine embryo development and quality, assessed by quantification of expression of various genes related to metabolism, oxidation, implantation and apoptosis. In addition, plasminogen activator activity (PAA) and plasminogen activator inhibition (PAI) were measured in the spent media. After conventional IVM, 2016 cumulus‐oocyte complexes (COCs) were divided into four groups with modified composition of the IVF medium containing t‐PA and/or its inhibitor epsilon‐aminocaproic acid (control, t‐PA, t‐PA+ε‐ACA, ε‐ACA). Presumptive zygotes were cultured for 8 days in synthetic oviductal fluid (SOF) medium; gene expression studies were carried out on morulae and blastocysts. t‐PA alone significantly suppressed cleavage and blastocyst formation rates, but this effect was neutralized by the addition of ε‐ACA. PAA in the treated group was significantly reduced by ε‐ACA, but without total elimination. Significant differences were detected in the expression of genes related to apoptosis and/or cell cycle arrest (BAX, BCL2L1, KAT2B) between embryos produced in t‐PA‐modified media and controls, giving an overall notion that the inferior developmental competence of treated embryos may be attributed to apoptotic phenomena induced by t‐PA. In conclusion, it appears that excessive t‐PA content in the IVF media, suppresses blastocyst formation rate, possibly due to induction of apoptotic phenomena. 相似文献
4.
PJ CANFIELD L. VOGELNEST ML CUNNINGHAM GS VISVESVARA 《Australian veterinary journal》1997,75(2):97-100
Objective
To describe a case of meningoencephalitis caused by Balamuthia mandrillaris in an orang utan.
Design
A pathological case report.
Animal
A 20 years old male orang utan (Pongo pygmaeus).
Procedure
The disease process was investigated by clinical pathology, necropsy, histopathology and immunofluorescence labelling.
Results
The orang utan developed sudden onset of depression, lethargy, inappetence and apparent head pain. The condition was considered to be related to a 2 year history of upper and lower respiratory disease, and the animal was placed on antibiotics after extensive testing. By the seventh day the animal had become ataxic and disoriented and a brain abscess was suspected. He died on the ninth day of illness. At necropsy, and subsequent sectioning, the brain showed multiple circular, soft, white to grey brown areas of varying size, the largest being in the left temporal (3.5 cm diameter) and right occipital (2.5 cm diameter) regions of the cerebrum. Histological examination of these regions revealed many amoebic trophozoites and occasional cysts associated with areas of haemorrhage and inflammatory necrosis. The trophozoites were packed in perivascular spaces and their nuclei often contained two or more prominent nucleoli. Immunofluorescent labelling of histological sections suggested that the agent was B mandrillaris.
Clinical implications
This report provides further evidence that B mandrillaris , a free living amoeba, can act as a pathogen in animals as well as people, and cause fatal meningoencephalitis. Along with Naegleria and Acanthamoeba spp, B mandrillaris should be considered amongst the causes of acute onset meningoencephalitis in animals. 相似文献
To describe a case of meningoencephalitis caused by Balamuthia mandrillaris in an orang utan.
Design
A pathological case report.
Animal
A 20 years old male orang utan (Pongo pygmaeus).
Procedure
The disease process was investigated by clinical pathology, necropsy, histopathology and immunofluorescence labelling.
Results
The orang utan developed sudden onset of depression, lethargy, inappetence and apparent head pain. The condition was considered to be related to a 2 year history of upper and lower respiratory disease, and the animal was placed on antibiotics after extensive testing. By the seventh day the animal had become ataxic and disoriented and a brain abscess was suspected. He died on the ninth day of illness. At necropsy, and subsequent sectioning, the brain showed multiple circular, soft, white to grey brown areas of varying size, the largest being in the left temporal (3.5 cm diameter) and right occipital (2.5 cm diameter) regions of the cerebrum. Histological examination of these regions revealed many amoebic trophozoites and occasional cysts associated with areas of haemorrhage and inflammatory necrosis. The trophozoites were packed in perivascular spaces and their nuclei often contained two or more prominent nucleoli. Immunofluorescent labelling of histological sections suggested that the agent was B mandrillaris.
Clinical implications
This report provides further evidence that B mandrillaris , a free living amoeba, can act as a pathogen in animals as well as people, and cause fatal meningoencephalitis. Along with Naegleria and Acanthamoeba spp, B mandrillaris should be considered amongst the causes of acute onset meningoencephalitis in animals. 相似文献
5.
Identification of a diverse mini‐core panel of Indian rice germplasm based on genotyping using microsatellite markers 下载免费PDF全文
Kapil K. Tiwari Anshuman Singh Sasmita Pattnaik Maninder Sandhu Sukhdeep Kaur Sourabh Jain Sushma Tiwari Shweta Mehrotra Mahender Anumalla Rashmita Samal Jyoti Bhardwaj Neha Dubey Vikrant Sahu Gayle A. Kharshing Patu K. Zeliang Kadiri Sreenivasan Pankaj Kumar Swarup K. Parida Sevanthi V. A. Mithra Vandana Rai Wricha Tyagi Pawan K. Agrawal Atmakuri R. Rao Arunava Pattanayak Girish Chandel Ashok K. Singh Ishwari S. Bisht Kangila V. Bhat Gundimeda J. N. Rao Jitendra P. Khurana Nagendra K. Singh Trilochan Mohapatra 《Plant Breeding》2015,134(2):164-171
Identification of a small core germplasm set representing the available genetic diversity is essential for its proper evaluation and subsequent utilization in rice improvement programmes. For constituting a small diverse mini‐core panel of Indian rice germplasm, a representative set of 6912 accessions drawn based on their geographic origin from the whole rice germplasm collection available in the National Gene Bank was genotyped using 36 microsatellite markers. Automated fragment analysis of amplicons yielded a total of 435 alleles, with an average 12.4 and range of 3–29 alleles per locus. Polymorphism information content (PIC) ranged from 0.08 (RGNMS190) to 0.86 (RM552) with an average of 0.528. Based on genotyping data, a mini‐core consisting of 98 genotypes was identified. Ninety‐four per cent of the alleles present in the core set were present in the mini‐core. The identified small but diverse panel will be useful for further intensive trait‐specific evaluation and utilization in allele mining. 相似文献
6.
I. S. Bisht K. S. Rao D. C. Bhandari Sunil Nautiyal R. K. Maikhuri B. S. Dhillon 《Genetic Resources and Crop Evolution》2006,53(7):1333-1350
There is a growing realisation world over that the introduction of modern agriculture has to be supplemented with measures
to conserve biodiversity in situ if yield gains are to be stabilized. Hence, there is a growing interest from agricultural development specialists and conservation
biologists for understanding the socioeconomic factors determining the conservation of biodiversity in situ. The present study was conducted with the objective of understanding the in situ (on-farm) conservation of agrobiodiversity in traditional agroecosystems taking the Urgam valley in north-western Himalaya
of India, as a case study. An inventory was made of traditional crops and wild economic species for subsistence, and the structure
of forest resource base, traditional knowledge related to resource management and use. Institutional and scientific challenges
for in situ (on-farm) management of crop diversity were studied and are discussed in this paper. Complementarity of in situ (on-farm) conservation with ex situ conservation together with crop improvement in such marginal areas are suggested. 相似文献
7.
Feeding and casting activity of Amynthas alexandri fed on corn, wheat leaves, and mixed grasses were monitored in laboratory cultures. Casts were produced on the surface and sides of the containers. Food consumption varied from 36.5 to 69 mg g–1 live worm day–1. Cast production ranged from 3.95 to 5.9 mg g–1 live worm day–1. The C:N ratio in casts in laboratory cultures (11.17) and in field samples (8.84) was consistently lower than the corresponding ratio in the parent soil (13.19 and 10.54, respectively). This was probably due to mineralization of plant-derived organic material during passage through earthworms with consequent low C:N ratios. 相似文献
8.
Mangal Deep Tuti Ramesh Singh Pal Dibakar Mahanta Brij Mohan Pandey Jaideep Kumar Bisht 《Communications in Soil Science and Plant Analysis》2020,51(7):948-962
ABSTRACTLack of crop diversification with suitable vegetable-based cropping system is a major constraint in limiting the productivity and sustainability of north-western Indian sub-Himalayas. To find out a sustainable vegetable-based cropping system in this region, a three year colocasia-based vegetable intensive experiment was conducted at Hawalbagh, Almora, India in a sandy clay loam soil under sub-temperate climatic conditions. Seven colocasia-based vegetable cropping systems along with rice–wheat system were compared under recommended package and practices. The system productivity in terms of colocasia equivalent yield was highest under colocasia–onion–frenchbean (52.38 Mg ha?1) system. Sustainable yield index was highest with colocasia–gardenpea–frenchbean system (0.86). After 3 years, total soil organic carbon (0–5%), available N (2–22%), P (–7% to 14%) and K (3–15%) concentrations were increased in all cropping systems except rice–wheat system, where negative balance of available P (7%) was observed over that of initial soil. Significantly higher soil microbial activity, soil carbohydrate, dehydrogenase, protease, acid and alkaline phosphatases activity were observed under colocasia–onion system. The results suggest that colocasia–onion–frenchbean system with higher productivity improves soil fertility and enhances enzymatic activities. 相似文献
9.
10.
V Aksyuk FF Balakirev GS Boebinger PL Gammel RC Haddon DJ Bishop 《Science (New York, N.Y.)》1998,280(5364):720-722
A silicon micromechanical magnetometer was constructed and successfully used in 60-tesla pulsed magnetic fields of less than 100-millisecond duration. The device is small, inexpensive to fabricate, and easy to use. It features a fast mechanical response (up to 50,000 hertz) and extremely high sensitivity yet is relatively robust against electrical and mechanical noise. Quantum oscillations in the magnetization of a 1-microgram sample of an organic superconductor, kappa-[bis(ethylenedithio)tetrathiafulvalene]2Cu(NCS)2, have been observed with this device. 相似文献