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51.
The phonon density of states of the geophysically important mineral forsterite has been calculated with a rigid-ion model, which gives good agreement with an experimental measurement by inelastic neutron scattering. The density of states has been used to calculate the specific heat as a function of temperature, the results of which are in excellent agreement with calorimetrically measured values. The rigid-ion model takes account of the interatomic interactions and normal modes of vibration on a detailed microscopic basis, and is therefore more realistic than the Debye and other empirical models used previously. 相似文献
52.
Along with most widely practiced resources conserving technology zero-tillage wheat after rice, adoption of permanent beds for rice–wheat rotation is also gaining popularity. Since relatively a new approach particularly for dry-seeded rice and permanent beds for wheat, very little information is known about permanent beds on soil properties, nutrient (N) use efficiency, and system productivity. A field experiment was carried out in a Typic Haplustept soil of New Delhi, India to study the effect of permanent beds on soil hydro-physical properties, root growth, nitrogen uptake, and system productivity of irrigated rice–wheat rotation. Results revealed that direct-seeded rice followed by wheat on permanent beds irrigated at different soil water tensions (field capacity, 20 and 40 kPa) reflected a significant variation in soil hydro-physical properties, reduced total nitrogen uptake, contribution by different plant parts, and N use efficiency compared to wheat after flooded transplanted rice system. Rice root weight density at flowering was also significantly low at 0–15 cm depth but higher at 15–60 cm depth in dry-seeded rice on beds. System productivity of rice–wheat rotation was 25–33% lower in permanent beds compared to flooded transplanted system. For wider acceptability of permanent beds as a promising resource conserving technology, system productivity needs to be improved. 相似文献
53.
R. Sri Hari Babu D. Lokeshwar N. S. Rao B. R. Bhaskar Rao 《The Journal of Horticultural Science and Biotechnology》2013,88(2):315-320
SummaryChilli plants cv. Pusa Jwala were inoculated in the nursery beds with three mycorrhizal fungi, Gigaspora calospora, G. margarita and Glomus fasciculatum and transplanted to plots supplied with 0, 25 and 50% of a recommended P level (65 kg ha?1). Uninoculated plants were also transplanted at 0 (Control) and 100% of.the recommended P level. Plant growth, height, shoot dry weight, uptake of P, root colonization and yield of green chillies were measured. Chilli responded well to inoculation and P. G. margarita best improved growth and yield. Inoculation plus 25 and 50% P were equally better than the control and equal to uninoculated plants at 100% P. As much as 50–75% P can be dispensed with by inoculation with mycorrhizal fungi and this represents a considerable economic saving in cost. 相似文献
54.
K. Hajira S. M. Sundaram R. S. Laha G. Yugander A. M. Balachandran S. C. Viraktamath B. Sujatha K. H. Balachiranjeevi C. Pranathi K. Anila M. Bhaskar S. Abhilash V. K. Mahadevaswamy H. Kousik M. Dilip Kumar T. Harika G. Rekha G. 《水稻科学》2016,23(3):144
In marker-assisted breeding for bacterial blight(BB) resistance in rice, three major resistance genes, viz., Xa21, xa13 and xa5, are routinely deployed either singly or in combinations. As efficient and functional markers are yet to be developed for xa13 and xa5, we have developed simple PCR-based functional markers for both the genes. For xa13, we designed a functional PCR-based marker, xa13-prom targeting the In Del polymorphism in the promoter of candidate gene Os8N3 located on chromosome 8 of rice. With respect to xa5, a multiplex-PCR based functional marker system, named xa5 FM, consisting of two sets of primer pairs targeting the 2-bp functional nucleotide polymorphism in the exon II of the gene TFIIA5(candidate for xa5), has been developed. Both xa13-prom and xa5 FM can differentiate the resistant and susceptible alleles for xa13 and xa5, respectively, in a co-dominant fashion. Using these two functional markers along with the already reported functional PCR-based marker for Xa21(p TA248), we designed a single-tube multiplex PCR based assay for simultaneous detection of all the three major resistance genes and demonstrated the utility of the multiplex marker system in a segregating population. 相似文献
55.
S. Sarao Preetinder K. Sahi Gurpreet Neelam Kumari S. Mangat Gurjit C. Patra Bhaskar Singh Kuldeep 《水稻科学》2016,23(4):219
Out of 1 989 wild accessions sown in seed boxes for screening, only 1 003 wild accessions with good germination were screened against brown planthopper (BPH), Nilaparvata lugens (Stål) under greenhouse conditions. The collection comprised of accessions from 11 wild species and African cultivated rice. The germplasm was screened for BPH following standard seed box screening technique in the greenhouse. As many as 159 accessions were identified as resistant during the year 2012 based on one year screening. A selected set of BPH resistant accessions were screened again during 2013. Based on the two years screening, seven accessions of O. nivara (AA), one accession of O. officinalis (CC), seven accessions of O. australiensis (EE), five accessions of O. punctata (BB and BBCC) and nine accessions of O. latifolia (CCDD) were confirmed to be resistant to BPH. So far no BPH resistance genes have been identified and designated from O. nivara and O. punctata, hence these may act as new sources of resistance. 相似文献
56.
Background: Pregnancy associated glycoproteins form a diverse family of glycoproteins that are variably expressed at different stages of gestation. They are probably involved in immunosuppression of the dam against the feto- maternal placentome. The presence of the products of binucleate cells in maternal circulation has also been correlated with placentogenesis and placental re-modeling. The exact structure and function of the gene product is unknown due to limitations on obtaining purified pregnancy associated glycoprotein preparations. Results: Our study describes an in silico derived 3D model for bubaline pregnancy associated glycoprotein 2. Structure-activity features of the protein were characterized, and functional studies predict bubaline pregnancy associated glycoprotein 2 as an inducible, extra-cellular, non-essential, N-glycosylated, aspartic pro-endopeptidase that is involved in down-regulation of complement pathway and immunity during pregnancy. The protein is also predicted to be involved in nutritional processes, and apoptotic processes underlying fetal morphogenesis and re- modeling of feto-maternal tissues. Conclusion: The structural and functional annotation of buPAG2 shall allow the designing of mutants and inhibitors for dissection of the exact physiological role of the protein. 相似文献
57.
Background
Pregnancy associated glycoproteins form a diverse family of glycoproteins that are variably expressed at different stages of gestation. They are probably involved in immunosuppression of the dam against the feto-maternal placentome. The presence of the products of binucleate cells in maternal circulation has also been correlated with placentogenesis and placental re-modeling. The exact structure and function of the gene product is unknown due to limitations on obtaining purified pregnancy associated glycoprotein preparations.Results
Our study describes an in silico derived 3D model for bubaline pregnancy associated glycoprotein 2. Structure-activity features of the protein were characterized, and functional studies predict bubaline pregnancy associated glycoprotein 2 as an inducible, extra-cellular, non-essential, N-glycosylated, aspartic pro-endopeptidase that is involved in down-regulation of complement pathway and immunity during pregnancy. The protein is also predicted to be involved in nutritional processes, and apoptotic processes underlying fetal morphogenesis and re-modeling of feto-maternal tissues.Conclusion
The structural and functional annotation of buPAG2 shall allow the designing of mutants and inhibitors for dissection of the exact physiological role of the protein. 相似文献58.
Phan Thi Cong Tran Dang Dung Tran Minh Hien Nguyen Thanh Hien Abu T.M.A. Choudhury Mihály L. Kecskés Ivan R. Kennedy 《European Journal of Soil Biology》2009,45(1):52-61
Field experiments were conducted during successive rainy seasons in 2006 in the Chau Thanh district of southern Vietnam to evaluate the effects of an inoculant plant growth promoter product called “BioGro” and N fertiliser rates on yield and N and P nutrition of rice. The results indicated that inoculation with BioGro, containing a pseudomonad, two bacilli and a soil yeast, significantly increased grain and straw yields and total N uptake in both seasons, as well as grain quality in terms of percentage N. Nitrogen fertilisation increased grain and straw yields as well as total N and P uptakes significantly in both cropping seasons. The estimated grain yield response to added N was quadratic in nature with and without added BioGro. In the first crop, BioGro out-yielded the control up to 90 kg urea N ha?1 whilst in the second season the beneficial effect of BioGro was observed up to 120 kg urea N ha?1, indicating either an interaction of the inoculant with higher yielding seasonal conditions or a cumulative effect of BioGro application. In the first season, the estimated N rate for maximum grain yield was 103 kg N ha?1 with BioGro while it was 143 kg N ha?1 without BioGro. The maximum estimated grain yields were 3.21 and 3.18 t ha?1 with and without BioGro, respectively. This information indicates that BioGro was able to save 40 kg N ha?1 with an additional rice yield of 30 kg ha?1 in the season. In the second rainy season, the estimated N rates for maximum grain yields were 94 and 97 kg N ha?1 with and without BioGro, respectively. The estimated maximum grain yields were 3.49 and 3.25 t ha?1 with and without BioGro, respectively. The two seasons’ combined results indicate that application of BioGro improved the efficiency of N use by rice significantly, saving 43 kg N ha?1 with an additional rice yield of 270 kg ha?1 in two consecutive seasons at the experimental site. The extra efficiency was shown by the fact that the same yield of rice was obtained with about 40 and 60 kg less fertiliser-N that the maximum yields with urea alone in the two successive harvests on the same plots. 相似文献
59.
Edmonds RL Deb Choudhury S Haverkamp RG Birtles M Allsop TF Norris GE 《Journal of agricultural and food chemistry》2008,56(17):7934-7941
The effects of conventional lime sulfide depilation and enzymatic depilation on the enamel layer of pickled lamb pelts were examined using atomic force and optical microscopy, immunohistological, and proteomic techniques. Microscopy showed that the surface structure of enzymatically depilated material was visibly less organized than conventionally processed material, implying that the enzymes used for depilation were responsible for this difference. Proteomic analyses identified an absence of collagen VI in the enamel of skins that had been processed with enzymes, in contrast to the skins that had been processed using conventional methods, which was confirmed using immunolocalization studies. It is therefore possible that the destruction of collagen VI during enzymatic depilation may cause the changes to the enamel structure observed during enzyme processing and in turn affect the quality of the finished product. 相似文献
60.
Photolysis of chlorimuron-ethyl was studied on a soil surface under sunlight and UV light. Eight photoproducts were isolated and characterised by spectroscopic methods. Major photoproducts are formed by cleavage of the sulfonylurea bridge and minor products are formed via dechlorination, hydrolysis and cyclisation. The rates of photodegradation of chlorimuron-ethyl on different soils followed first-order rate kinetics, with half lives of 22·3 h, 9·4 h, 4·9 h (UV) and 20·7 days, 11·1 days and 11·1 days (sunlight) for alluvial, red and laterite soils, respectively. The differences in rates of photodegradation were dependent upon the soil pH. © 1997 SCI 相似文献