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51.
Understanding variability in seed germination among populations is essential for planning an effective germplasm collection for restoration and conservation purposes.The knowledge of germination and dormancy patterns among populations of desert grasses is crucial for determining the potential of the species and populations to be used for restoration and conservation as well as forage production.Variability in seed germination of Panicum turgidum Forssk and Pennisetum divisum(Gmel.)Henr.in the desert of Kuwait was evaluated in different populations in May 2017.Experiment of seed germination(25 seeds and 4 replicates)was conducted for each population at night/day temperatures of 15℃/20℃and 20℃/30℃under the following light condition:continuous darkness or 12 h/12 h light/dark.Results showed that seed masses of both species strongly varied according to their seed provenances,and both species produced heavier seeds in population with a higher soil electrical conductivity.Seed germination percentage considerably varied between two species,and the variation in P.turgidum was greater(17%–49%)than that of P.divisum(72%–93%).Germination percentage in P.turgidum was greater at high temperature(20℃/30℃)than at low temperature(15℃/20℃).However,temperature regimes had no effect on germination percentage of P.divisum seeds.Mean germination time of both species exhibited significant inter-population variability.This result is especially relevant to assure the selection of the best population of each species and the regeneration success of the species.Besides this,inter-population variability also provides valuable information for enhancing our understanding of the mechanisms that regulate seed germination and how they might be related to seed provenance.  相似文献   
52.
Veterinarians working under remote field conditions are routinely presented with variety of surgical interventions in equines like castrations, management of wound, traumatic and congenital hernias and musculoskeletal disorders thus necessitating the use of general anaesthesia for management of these conditions. The present study was carried out to evaluate and recommend the suitable short term anaesthetic technique for Spiti ponies under field conditions. Seven clinically healthy male Spiti ponies presented for castration were evaluated for short term Total Intravenous Anaesthesia (TIVA) using detomidine (0.02 mg kg(-1)), butorphanol (0.01 mg kg(-1)), 5% guaifenesin (20 mg kg(-1)) and ketamine (2.0 mg kg(-1)). The studies conducted were open label trials and all the animals received same treatment. After proper tetanus prophylaxis and preanesthetic fasting, detomidine was administered intravenously. Subsequently at head down position the animals received butorphanol intravenously. Thereafter, guaifenesin was administered intravenously. As soon as the signs of ataxia developed, the induction of surgical anaesthesia was achieved by intravenous administration of ketamine hydrochloride. The onset of sedation was observed in 2.43 +/- 0.53 min following detomidine administration and the animals were ataxic in 1.43 +/- 0.43 min after butorphanol and guaifenesin administration when ketamine was injected. The ponies were in surgical plane of anaesthesia within 2.28 +/- 0.42 min following ketamine administration. During recovery the limb/head movement and sternal recumbency were attained in 18.71 +/- 1.98 and 26.14 +/- 1.62 min, respectively whereas standing ataxia and normal gait were seen at 29.42 +/- 3.21 and 71.14 +/- 4.74 min, respectively. There was excellent to good muscle relaxation. The surgical anaesthesia remained for 22.57 +/- 1.48 min. The recovery was smooth. Moderate to good suppression of palpebral and corneal reflexes were observed immediately after induction and during anaesthesia. The analgesia was excellent. A highly significant (p < 0.01) to significant (p < 0.05) decrease in respiration rate was observed after induction, during anaesthesia and after recovery. The mean SpO2 value in equines of this group was 76.50 +/- 4.14 and 83.33 +/- 4.18% after induction and during anaesthesia, respectively. Some of the blood biochemical parameters like plasma alanine amino transferase (ALT), total proteins and glucose showed significant increase without clinical consequence. It was concluded that detomidine (0.02 mg kg(-1)), butorphanol (0.01 mg kg(-1)), guaifenesin 5% (20 mg kg(-1)) and ketamine (2.0 mg kg(-1)) combination can safely be used for short term total intravenous anaesthesia in equines under field conditions where the monitoring facilities are meager.  相似文献   
53.
The study of genetic variability is a prerequisite for any tree improvement program. Screening of clones showing the effect of dominance in growth and tree form is essential to identify productive clones, matched to sites. Our study performed in a clonal seed orchard at Lacchiwala of India, represented by 31 clones of Dalbergia sissoo (Shisham) Roxb. from diverse locations revealed significant variability at the 0.1% level of significance in various morphological traits. At the age of 13 years, clone 196 (Gonda) revealed maximum height of 20.2 m and a girth at breast height of 74.2 cm. The five identified clones viz. 196, 198, 192, 123 and 235 were well adapted to the climatic conditions of this zone, hence survived well and showed good performance compared to other clones. Heritability estimates of 87%, 83% and 80% for height, crown width and crown length respectively coupled with high genetic gains indicated strong genetic control of these variables. A correlation matrix of various growth attributes revealed positive correlation among these attributes. On the basis of the entire set of growth variables, the clones were grouped into two major clusters with three subgroups.  相似文献   
54.
The viscoelastic properties of high molecular weight polymeric liquids are dominated by topological constraints on a molecular scale. In a manner similar to that of entangled ropes, polymer chains can slide past but not through each other. Tube models of polymer dynamics and rheology are based on the idea that entanglements confine a chain to small fluctuations around a primitive path that follows the coarse-grained chain contour. Here we provide a microscopic foundation for these highly successful phenomenological models. We analyze the topological state of polymeric liquids in terms of primitive paths and obtain parameter-free, quantitative predictions for the plateau modulus, which agree with experiment for all major classes of synthetic polymers.  相似文献   
55.
Summary Generation of Simple Sequence Repeat (SSR) DNA markers was based on the construction of genomic DNA library of avocado (Persea americana M.). The library was screened with the four dinucleotide probes (AG), (AT), (GC) and (CA). Positive clones were sequenced to validate the presence of simple sequence repeats (SSR) and to generate polymerase chain reaction (PCR) primers based on the sequences flanking the simple sequence repeat. Twenty six different pairs of primers which yield a PCR product in the initial screening were synthesized. The SSR A1E11 was found to have eleven alleles while A3F8 has eight alleles. The SSRs in avocado were found to be inherited in a Mendelian fashion.Contribution from the Agricultural Research Organization, The Volcani Center, Bet-Dagan, Israel. No. 1335-E, 1994 series.  相似文献   
56.
Bovine brucellosis is endemic in many parts of the world including India. The disease diagnosis and surveillance are usually carried out by serological tests, which however have drawbacks. This study was undertaken to evaluate the potential of real-time PCR (RT-PCR) targeting bcsp31 gene for surveillance of bovine brucellosis. A total of 461 samples, which included 408 stored serum and 53 prospective blood samples, were used. It was found that 33 (7.15 %) samples were positive by RT-PCR, whereas 149 (32.32 %) and 132 (28.63 %) were positive by Rose Bengal plate test (RBPT) or standard agglutination test (STAT), respectively. The results of this study suggest that RT-PCR targeting bcsp31 gene carried out on DNA extracted from serum or blood may not be a suitable method for surveillance of brucellosis in bovines.  相似文献   
57.
Correlation between lysine, tryptophan and prolamine contents during maturation of the maize kernel
Changes in the contents of total nitrogen, prolamine, tryptophan and protein bound lysine, and the relative nutritive quality of proteins were studied during the maturation of three normal maize varieties, grown under the same topographical and agrotechnical conditions, in two successive crop years.
Total nitrogen was determined according to Kjeldahl's method, prolamine by the turbidity test, lysine by Carpenter's method and tryptophan was assessed fluorometrically.
A significant decrease (p = 0.01) in total nitrogen, tryptophan and bound lysine content in the dry grain matter was found in the late milk and early dough ripeness stages of the maize kernel. Parallel with the decrease in these components, the relative nutritive quality of proteins also decreased during maturation. Prolamine, which was present in the early milk stage in low quantities, increased significantly (p = 0.01) with kernel maturity, reaching the highest level in the early dough ripeness stage. During further kernel maturation no significant changes in the components studied were observed. The correlation coefficients between the contents of prolamine and total nitrogen, lysine and tryptophan, during the ripening of maize kernel were highly significant (p = 0.001): -0.891, -0.938, -0.856, respectively in the first crop year and –0.844, -0.833, -0.867, respectively in the second crop year.  相似文献   
58.
A total of 45 cyanobacterial strains isolated from rice fields near Loktak Lake in Manipur, India were tested for their rice root colonization capacity under light and under darkness. Twenty-one of these strains showed significant colonization of rice roots. The average colonization values were 637 and 381?μg chl a g?1 root dry wt in N2 medium and 792 and 451?μg chl a g?1 root dry wt in NO 3 ? medium under light and darkness, respectively. Thus, while the colonization was higher under light and in NO 3 ? medium, there was significant level of colonization under darkness in N2 medium (381?μg chl a g?1 root dry wt). A 16S rRNA gene fragment-based denaturing gradient gel electrophoresis analysis revealed difference in the competence of individual strains to colonize rice roots exposed to individual or mixed population. The colonization pattern of seven strains used in competition experiments was found to be biphasic. A 16S rRNA gene-based phylogenetic analysis revealed high level of molecular similarity among strains of Nostoc and Anabaena.  相似文献   
59.
60.
Genome mapping of any organism has become vital and most essential to control the gene related functions and also for the production of new traits of the desired properties. Gene mapping has become a very powerful tool in agriculture sector as well as for terrestrial livestock and going to revolutionize both these sectors from the point of view of enhancing production. However, for aquatic organisms, the information pertaining to gene mapping research is limited and only in recent past few attempts have been made in this direction. The rationale behind genome mapping particularly for aquaculture species is to improve the quality of animals through selective breeding and produce genetically superior traits for commercial production. There is a great potential in this field since most of the aquaculture species have not been subjected to genetic improvement. The advantage of gene mapping tool for any organism is to identify and characterize quantitative trait loci associated with commercial important traits and to use these markers in marker‐assisted selection programmes. Now with advent of gene editing (CRIPSR‐Cas) technology one can modify/repair the gene structure and remove the adverse impact of the gene related characters without replacing the whole genome. Gene mapping of polygenic traits of aquaculture species is also gaining lot of importance because of dominant nature of such additional functional genes with unique predominant character in the species. In the present review, attempts have been made to collect details of information on gene mapping of cultivable penaeid shrimps. Furthermore, how these gene maps can be used to modify the gene structure at the targeted cites using gene editing techniques, has also been discussed.  相似文献   
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