Non-puddled transplanting of rice reduces life cycle greenhouse gas emission

Wetland rice (Oryza sativa L.) production contributes 55% of agricultural greenhouse gas (GHG) emissions globally. Hence, any new technology with the potential to reduce the GHG emissions from wetland rice could make a significant contribution to total global warming mitigation by agriculture. Incorporation of conservation agriculture (CA) in the rice–based triple cropping system in the EGP remains a challenge. Measures to reduce CH4 emissions from rice fields often lead to increased N2O emissions, and this trade–off between CH4 and N2O is a major hurdle in reducing global warming potential (GWP) of wetland rice. Ideal strategies would reduce emissions of both CH4 and N2O simultaneously. A novel solution to these constraints for rice production is non-puddled transplanting of rice. The recent development of NP of rice together with residue retention is suitable for CA. A life cycle assessment (LCA) analysis of the new NP rice production technology can estimate its potential contribution to GWP. The present study was carried out to: assess the GHG emissions for conventional puddling and NP with different levels of crop residue retention; determine the hotspots contributing significantly to the GHG emissions within the system boundaries by a LCA study, and identify the causes for the predominant GHG emissions during the pre– and on–farm stages of rice production

Increases in soil sequestered carbon under conservation agriculture cropping decrease the estimated greenhouse gas emissions of wetland rice using life cycle assessment

Wetland rainfed rice (Oryza sativa L.), which covers 60 million hectares in South Asia, contributes significantly to agricultural greenhouse gas (GHG) emissions. Mitigation strategies for GHG emissions by wetland rice production are of considerable importance. Life cycle assessment of GHG emissions can be used to assess the mitigation potential of new rice production practices such as seedling establishment on non-puddled soil. The aim of the study was firstly to determine the GHG mitigation potential of rain-fed rice production by changing to non-puddled transplanting and increased crop residue retention and secondly to determine the addition contribution of soil carbon sequestration to net GHG emissions with the altered crop establishment approach. A cradle to farm-gate Life Cycle Analysis was used to calculate GHG emissions associated with monsoon rice production in rice-based intensive cropping systems of Northwest Bangladesh. The non-puddled transplanting and low residue retention decreased the net life cycle assessment GHG emissions (CO2eq) by 31 % in comparison with the current puddled transplanting and increased crop residue retention. By contrast, non-puddling with increased residue retention reduced emission of the net GHG by 16 % in comparison with current puddling and low residue retention. Regardless of rice establishment practices, CH4 was the most prevalent GHG emission comprising 63 to 67 % of the total GHGs, followed by 17–20 % from CO2 emissions from the field. The GHG emissions tonne-1 rice after accounting for soil carbon storage ranged from 1.04 to 1.18 tonne CO2eq for non-puddling with low and increased crop residue retention, respectively. The inclusion of soil carbon in the footprint equation represents a 26 % reduction of estimated GHG emissions under non-puddled soil with increased residue retention. Overall, non-puddled transplanting with increased crop residue retention was an effective GHG mitigation option in wetland monsoon rice production because the increased yield and extra soil organic carbon storage more than offset its higher CH4 emissions than with low residue retention

Maximum parsimony based resolution of inter-species phylogenetic relationships in citrus l. (Rutaceae) using its of rDNA

The present study aims to analyse phylogenetic relationships, using internal transcribed spacer sequence data of ribosomal DNA (rDNA), across 24 Citrus species and close relatives by the evaluation of several parameters such as nucleotide substitution (r), nucleotide diversity (π) and the estimated values of transition/transversion bias (R). The observed results indicated the presence of a wide divergence pattern of rDNA in subfamily Aurantioideae. Maximum parsimony (MP) analysis inferred divergence pattern in the Citrus genus. We observed seven strongly supported clades among the subfamily Aurantioideae. We postulate that the present investigation provides a more robust topology of Citrus and its close relatives, which can significantly prove as an additional support to resolve the phylogenetic relationships in Citrus genera. Therefore, sequences of noncoding regions should exhibit more phylogenetically informative sites than the coding regions do, which is in accordance with the present study

Performances of linseed oil-free bakelite RPC prototypes with cosmic ray muons

A comparative study has been performed on Resistive Plate Chambers (RPC) made of two different grades of bakelite paper laminates, produced and commercially available in India. The chambers, operated in the streamer mode using argon, tetrafluroethane and isobutane in 34:59:7 mixing ratio, are tested for the efficiency and the stability with cosmic rays. A particular grade of bakelite (P-120, NEMA LI-1989 Grade XXX), used for high voltage insulation in humid conditions, was found to give satisfactory performance with stable efficiency of > 96% continuously for more than 130 days. A thin coating of silicone fluid on the inner surfaces of the bakelite RPC is found to be necessary for operation of the detector.Comment: 6 figures, Presented in IX International Workshop on Resistive Plate Chamber and related Detectors-2007, TIFR, Mumbai, India, February 13-16, 200

Potential methane emission reduction strategies from rice cultivation systems in Bangladesh: a critical synthesis with global meta - data

Methane (CH4) is one of the dominant greenhouse gases (GHG) that is largely emitted from rice fields and thus, significantly contributes to global warming. Significant efforts have been made to find out suitable strategies to mitigate CH4 emission from rice culture. However, the effectiveness of these management practices is often diverse with negative, no, or positive impacts making it difficult to adopt under a particular condition. The diversity of rice cultivation in terms of agro-climatic conditions and cultivation practices makes it difficult for providing specific recommendations. Here, we collected data from a total of 198 studies reporting 1052 observations. The management practices are categorized into five different management practices i.e., water, organic and inorganic fertilizer management, crop establishment method, and agronomic practices while major categories were subdivided into different classes. To test statistically significant differences in the effectiveness between major management practices, an analysis of variance (ANOVA) was applied. The Gaussian and bootstrapping model were applied to find out the best estimate of the effectiveness of each practice. In addition, mechanisms controlling the CH4 emission reductions were synthesized. Next, the adoption potentials of these practices were assessed based on the existing rice cultivation systems in Bangladesh. Our results showed that water and organic matter management were the most effective methods irrespective of the growing conditions. When these technologies are customized to Bangladesh, water management and crop establishment methods seem most feasible. Among the rice-growing seasons in Bangladesh, there is a larger scope to adopt these management practices in the Boro season (December to May), while these scopes are minimal in the other two seasons due to their rain-fed nature of cultivation. Altogether, our study provides fundamental insights on CH4 reductions strategies from rice fields in Bangladesh

Evaluation of potential rice (Oryza sativa L.) genotypes with different levels of N under rainfed shallow lowland situation

A field experiment was conducted to evaluate the yield of potential rice genotypes during kharif season, 2012 and 2013 at Rice Research Station, Bankura, West Bengal, India on sandy loam soil of slightly acidic in reaction (pH: 5.7). This experiment was conducted in split-plot design with three replications. The results indicated that 105 kg N ha-1, the yield attributes recorded maximum number of panicles m-2 (307.9), panicle length (25.3cm), panicle weight (2.32g), number of filled grains per panicle (117.8), 1000-grains weight (24.5g) and finally recorded highest grain yield (4.80 t ha-1) than lower fertilities. While, 70 kg N ha-1 was remained closed to 105 kg N ha-1 in number of panicles m-2, panicle weight and number of filled grains per panicle. Among the potential rice varieties ‘Sampriti’ (IET 21987) recorded the highest grain yield (4.66 t ha-1) under rainfed shallow lowland situation of red and laterite zone of West Bengal. The highest grain yield (4.80 t ha-1) was obtained at 105 kg N ha-1and it was statistically at par with 70 kg N ha-1 (4.62 t ha-1). Therefore, the increased in grain yield of rice by the varieties due to overall respective performance in growth and appreciable improvement in the yield attributing characters

The Taming of Closed Time-like Curves

We consider a $R^{1,d}/Z_2$ orbifold, where $Z_2$ acts by time and space reversal, also known as the embedding space of the elliptic de Sitter space. The background has two potentially dangerous problems: time-nonorientability and the existence of closed time-like curves. We first show that closed causal curves disappear after a proper definition of the time function. We then consider the one-loop vacuum expectation value of the stress tensor. A naive QFT analysis yields a divergent result. We then analyze the stress tensor in bosonic string theory, and find the same result as if the target space would be just the Minkowski space $R^{1,d}$, suggesting a zero result for the superstring. This leads us to propose a proper reformulation of QFT, and recalculate the stress tensor. We find almost the same result as in Minkowski space, except for a potential divergence at the initial time slice of the orbifold, analogous to a spacelike Big Bang singularity. Finally, we argue that it is possible to define local S-matrices, even if the spacetime is globally time-nonorientable.Comment: 37 pages, LaTeX2e, uses amssymb, amsmath and epsf macros, 8 eps and 3 ps figures; (v2): Two additional comments + one reference added; (v3): corrections in discussion of CTCs + some clarification

Crystallographic structure reveals phosphorylated pilin from Neisseria : phosphoserine sites modify type IV pilus surface chemistry and fibre morphology

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72468/1/j.1365-2958.1999.01184.x.pd

Angiopoietin-1 promotes functional neovascularization that relieves ischemia by improving regional reperfusion in a swine chronic myocardial ischemia model

10.1007/s11373-006-9082-xJournal of Biomedical Science134579-59