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51.
The present study was conducted to evaluate the effect of histamine and to characterise its receptor subtypes in reticular groove (RG) smooth muscle of adult goats. The studies were done using floor and lip regions of RG. We used tension experiments on smooth muscle of RG isolated from adult goat for functional characterisation of H1 and H2 receptors. Western blotting and immunohistochemistry experiments were conducted for molecular characterisation of these receptors. Histamine evoked concentration-dependent contraction of isolated RG circular and longitudinal smooth muscle preparation. Pyrilamine antagonised the action of histamine. Histamine did not induce any relaxant effect on RG preparations. Additionally, cimetidine did not produce any significant effect on histamine-induced response. Non-selective histaminic receptor antagonist cyproheptadine attenuated the contraction response to histamine in the smooth muscle. Molecular characterisation and localisation of H1 and H2 receptor proteins confirmed the presence of these receptors in RG. It is most likely that histamine-induced contractile effect in RG smooth muscle of goats is mediated by H1 histaminic receptors.  相似文献   
52.
The interactive effect of potassium (K) and sulfur (S) fertilization on productivity and mineral nutrition of sunnhemp (Crotalaria juncea L.) was evaluated in a field experiment during 2008 and 2009 cropping seasons at Uttar Pradesh, India. Potassium and sulfur fertilizers increased fiber yield and nutrient uptake of sunnhemp. It was observed that an application of K and S at 40 kg ha?1 each significantly increased the total dry matter, fiber yield, and nutrient uptake of sunnhemp. The crop yield response to the added S was greater than for K and the nutrient use efficiency was also higher at lower levels of fertilizer addition. The increased levels of K and S improved the number of nodules and crude protein content of sunnhemp leaves.  相似文献   
53.
Plant growth-promoting bacteria (PGPB) Pseudomonas lurida-NPRp15 and Pseudomonas putida-PGRs4 possessing multiple plant growth-promoting traits were isolated from rhizoplane of pea and rhizosphere of garlic, respectively. The effects of individuals and combinations of Pseudomonas spp. with effective root nodulating symbiotic nitrogen fixing Rhizobium leguminosarum-FB1 on plant growth, nutrient uptake and yield of the rajmash plant were studied under greenhouse conditions. Bacterial inoculation resulted in significantly higher values for plant dry biomass, N, P, K, Zn and Fe contents as compared to the uninoculated control. Furthermore, dual inoculation of P. lurida-NPRp15 with R. leguminosarum-FB1 significantly increased root and shoot dry weight, nodulation, nutrient uptake, pod yield, and nutrient content of pods of rajmash VL63 compared to controls, single and triple inoculation. The results of the study indicate the potential of harnessing the benefit of plant growth-promoting and nitrogen-fixing microorganisms to improve the growth and yield of rajmash.  相似文献   
54.
Cation distribution in adsorbed and solution phases and their mobility in the soil profile are largely influenced by the cation exchange capacity and selectivity coefficient of the soil. Vermiculites (Vt) and montmorillonites (Mt) in acid soils and sediments are frequently interlayered by hydroxyaluminum (HyA). Such interlayering causes significant changes in various properties of Vt and Mt. We evaluated the contribution of HyA-induced frayed edge sites (FES) in Vt and Mt to the overall selectivity of K/Ca and NHJCa. A more preferential adsorption and exchange of K to Ca was observed in the case of Vt in contrast to Mt. The overall K/Ca selectivity of Vt increased markedly by HyA-interlayering, whereas that of Mt was slightly affected. An increased overall K/Ca selectivity, especially of Vt was also observed due to the larger amount of HyA adsorption at higher initial basicity of the HyA ionic solution. Selective adsorption of K and NH4 predominantly occurred on the FES. Interlayering substantially enhanced such FES contribution. The overall K/Ca and NH4/Ca selectivity coefficients did not indicate any striking competitiveness of NH4 with K, unlike that for the natural micaceous clay minerals. However, the parameter of FES contribution suggested that NH4 could be slightly more competitive with K for the FES. The relative abundance of FES on different clay specimens determining K/Ca and NH4/Ca selectivity and a slightly higher preference of NH4 to K on FES played a major role at low K or NH4-saturation.  相似文献   
55.
Direct-fed microbials(DFM), generally regarded as safe status, are successfully used in improving rumen ecology, gastro-intestinal health, feed efficiency, milk production and growth rate in ruminants. On the other hand, methanogenesis in rumen, which accounts for a significant loss of ruminant energy and increased greenhouse gas in environment, is of great concern, therefore, use of DFM for improving productivity without compromising the animal health and ecological sustainability is encouraged. The present study was conducted to investigate the methane reducing potential of bacteriocinogenic strain Pediococcus pentosaceus-34. Since, the culture showed no hemolysis on blood agar and DNase activity, hence, it was considered to be avirulent in nature, a prerequisite for any DFM. The culture also showed tolerance to pH 5.0 for 24 h with 0.5% organic acid mixture, whereas when given a shock for 2 h at different p H and organic acids concentrations, it showed growth at pH 3.0 and 4.0 with 0.1 and 1.0% organic acids, respectively, as having good animal probiotics attributes. The total gas production was significantly(P<0.05) higher in live pedicoccal culture(LPC) and dead pedicoccal culture(DPC) both with wheat straw, when compared to the control. In sugarcane bagasse, gas production was significantly lower(P<0.05) with LPC compared to the control and DPC both. Methane was reduced by the inclusion of LPC in sugarcane bagasse(0.07 mL CH4 mg–1 dry matter digestibility) with no effect on other rumen fermentation parameters. However, with wheat straw and LPC total gas, in vitro dry matter digestibility, total volatile fatty acids increased significantly but no reduction in methane production was observed in comparison to the control. Therefore, further research is warranted in this direction, if the bacteriocinogenic strains can be used as DFM for ruminants to improve the ruminant productivity.  相似文献   
56.
Backcrossed chromosome substitution lines (CS‐B) have been developed with a homologous pair of chromosomes or chromosome arms of Gossypium barbadense (3‐79) germplasm substituted for the homologous Gossypium hirsutum(TM‐1) chromosomes or chromosome segments. We report on agronomic and fibre trait performance of four backcrossed chromosome or chromosome arm substitution lines including chromosomes 01, 11sh (chromosome 11 short arm), 12 sh and 26 Lo (chromosome 26 long arm). Data for agronomic and fibre traits were collected from replicated field experiments at two different locations in 2 years, and analysed under an additive dominance genetic model. CS‐B 12sh had higher, while CS‐B 01 and CS‐B 26Lo had lower boll weight than TM‐1. The presence of significant negative additive effects for micronaire with CS‐B 01 and significant positive additive effects for elongation and fibre strength with CS‐B 11sh suggested the substituted chromosome arms of 3‐79 in these CS‐B lines were more likely carrying genes causing these effects. Results revealed that several CS‐B lines had significant homozygous and heterozygous dominance effects for different agronomic and fibre traits suggesting that specific CS‐B lines may be useful for improving agronomic and fibre traits in hybrid cottons. These CS‐B lines also provide novel genetic resources for improving upland cotton germplasm.  相似文献   
57.
58.
Variable adventitious rhizogenesis of juvenile shoot cuttings was observed in seven half-sib families (TP-1, BAN-1, AN-3, JR-3, SL-16, UM-3, and UM-5) of Albizia procera Benth. Treatment with IBA invariably promoted sprouting by 8%, adventitious rooting by 218%, root number by 869%, and root length by 36.4% compared with the control. Interaction between families and IBA treatment significantly enhanced sprouting and root length in BAN-1, JR-3, UM-3, and UM-5, and root number in all families, but had a significant suppressive effect on sprouting in AN-3. Treatment with IBA increased family heritability (h f 2) 1.38-fold for sprouting, 2.86-fold for adventitious rooting, and 10.86-fold for root number, but reduced family heritability by a factor of 8.25 for root length. Thus, direct genetic effects seem to have strongly affected sprouting and adventitious rooting, with IBA playing an auxiliary role, but had little effect on root number and length, for which IBA had a dominant regulatory role.  相似文献   
59.
Vyas D  Kumar S  Ahuja PS 《Tree physiology》2007,27(9):1253-1259
Tea (Camellia sinensis (L.) O. Kuntze) is a perennial crop grown throughout the world. During winter, tea undergoes a dormancy period when growth of apical buds almost ceases, severely reducing the commercial yield of tea. Low temperatures prevail during the period of winter dormancy, which alone or in combination with high solar irradiance have the potential to induce oxidative stress in plants. We studied six tea clones under field conditions to test whether a relationship exists between oxidative stress and winter dormancy. Data on the behavior of the enzymatic antioxidative system was collected for all clones during different phases of winter dormancy. There was a strong positive correlation among clones between accumulation of reactive oxygen species (ROS) and the length of the dormancy period. Clones having shorter dormancy periods exhibited higher induction of antioxidative enzymes. Results suggest that efficient scavenging of ROS is a desirable feature in tea because it leads to lower accumulations of ROS during winter months and is associated with reduced winter dormancy.  相似文献   
60.
The study was undertaken to estimate the genetic divergence among FG, IFG, FJG, IFJG, and R crosses of Gir cow on the basis of age at first conception, age at first calving, and lactation milk yield per day of lactation length using Mahalanobis D2 statistics. The genetic groups’ influence was significant (P?<?0.01) for all traits separately and simultaneously (V test) based on three traits. The differences in the D2 values among all the genetic groups’ combinations were significant except IFG with R genetic group combination. The total D2 values for age at first conception (AFCon), age at first calving (AFC), and lactation milk yield per day of lactation length (LMY/LL) were 18.85, 0.06, and 9.01 respectively. The percent contribution of AFCon to the total D2 value was maximum as 67.51 followed by LMY/LL as 32.27 and lowest of AFC as 0.22. Among the clusters formed on the basis of D2 values, IFG, IFJG, and R formed one cluster, whereas, FG and FJG formed second cluster. The magnitude of inter-cluster distance was greater than intra-cluster distance.  相似文献   
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