Seed biopriming induces a physiological condition that promotes germination and uniform seedling emergence. An investigation is carried out on different seeds such as carrot ( Daucus carota subsp. ...Sativus ), onion (Allium cepa L.) , cauliflower (Brassica oleracea) , radish, ( Raphanus sativus ), tomato (Solanum lycopersicum ), spinach (Spinacia oleracea) , fenugreek (Trigonella foenum-graecum) , and pea (Pisum sativum) to standardise bio-priming with Bacillus siamensis strain NKIT-9 to improve seed germination and seedling vigor index. To optimise the concentration of bio-priming seedlings were bioprimed overnight with Bacillus siamensis strain (NKIT-9) at varied concentrations (0.1mg/ml, 10µg/ml, 0.1µg/ml, and 10ng/ml). Bio-priming with Bacillus siamensis strain NKIT-9 gave highest values of germination percentage and seedling vigor index of carrot (at 0.1mg/ml), onion (at 0.1µg/ml ), cauliflower at 0.1mg/ml, 10µg/ml, and 0.1µg/ml), radish (at0.1mg/ml and 0.1µg/ml), tomato (at 0.1mg/ml), spinach (at 10ng/ml ), fenugreek (at 10ng/ml) and pea (a10ng/ml ) as compared with control. carrot, onion, cauliflower, radish, tomato, spinach, fenugreek, and pea exhibited higher germination percentages (60%, 100%, 100%, 100%, 80%, 90%, 100%, and 60% respectively) and seedling vigor indexes (148 ,720, 910, 880, 525, 580, 990, and 1018 respectively) when compared with control. Therefore, bio-priming with these concentrations is best suited for improving germination rate and seedling vigor of seeds.
The immune response of a host to a pathogen is typically described as either innate or adaptive. The innate form of the immune response is conserved across all organisms, including insects. Previous ...and recent research has focused on the nature of the insect immune system and the results imply that the innate immune response of insects is more robust and specific than previously thought. Priming of the insect innate immune system involves the exposure of insects to dead or a sublethal dose of microbes in order to elicit an initial response. Comparing subsequent infections in primed insects to non-primed individuals indicates that the insect innate immune response may possess some of the qualities of an adaptive immune system. Although some studies demonstrate that the protective effects of priming are due to a "loitering" innate immune response, others have presented more convincing elements of adaptivity. While an immune mechanism capable of producing the same degree of recognition specificity as seen in vertebrates has yet to be discovered in insects, a few interesting cases have been identified and discussed.
In recent decades, nano-scale zero valent iron is reported to have plant growth enhancement capacity under laboratory conditions, but till date, there is no report to highlight its effect on the ...growth and yield of field-grown plants. In this study, we have evaluated the potential of nZVI priming on rice yield. A two-year field study has been conducted with different concentrations (10, 20, 40, and 80 mg l
−1
) of nZVI for seed priming. The efficacy of nanopriming was compared with the hydroprimed control set. Seeds were treated for 72 h and sown in nursery beds and after 30 days seedlings were transplanted in the field. Root anatomy and morphology were studied in 7 days old seedlings where no changes were found. RAPD analysis also confirmed that low doses of nZVI were not genotoxic. Nanoprimed plants also had broader leaves, higher growth, biomass, and tiller number than control plants. Maximum yield was obtained from the 20 mg l
−1
nZVI primed set (3.8 fold higher than untreated control) which is achieved primarily because of the increase in fertile tiller numbers (two fold higher than untreated control). Higher values of other agronomic parameters like growth rate, net assimilation rate proved that nZVI priming enhanced photosynthetic efficiency and helped in the proper storage of photo-assimilates. All these attributed to increased accumulation of phytochemicals like starch, soluble sugar, protein, lipid, phenol, riboflavin, thiamine, and ascorbic acid in the grains. The elemental analysis confirmed that nZVI priming also promoted higher accumulations of macro and micronutrients in grains. Thus, nanoprimed seeds showed better crop performance compared to the traditional hydropimed seeds. Hence, nZVI can be considered as ‘pro-fertilizer’ and can be used commercially as a seed treatment agent which is capable of boosting plant growth and yield along with minimum interference to the soil ecosystem.
One notion emerging from studies on unconscious visual processing is that different "blinding techniques" seem to suppress the conscious perception of stimuli at different levels of the ...neurocognitive architecture. However, even when only the results from a single suppression method are compared, the picture of the scope and limits of unconscious visual processing remains strikingly heterogeneous, as in the case of continuous flash suppression (CFS). To resolve this issue, it has been suggested that high-level semantic processing under CFS is facilitated whenever interocular suppression is attenuated by the removal of visuospatial attention. In this behavioral study, we aimed to further investigate this "CFS-attenuation-by-inattention" hypothesis in a numerical priming study using spatial cueing. Participants performed a number comparison task on a visible target number ("compare number to five"). Prime-target pairs were either congruent (both numbers smaller, or both larger than five) or incongruent. Based on the "CFS-attenuation-by-inattention" hypothesis, we predicted that reaction times (RTs) for congruent prime-target pairs should be faster than for incongruent ones, but only when the prime was presented at the uncued location. In the invisible condition, we observed no priming effects and thus no evidence in support of the "CFS-attenuation-by-inattention" hypothesis. In the visible condition, we found an inverse effect of prime-target congruency. Our results agree with the notion that the representation of CF-suppressed stimuli is fractionated, and limited to their basic, elemental features, thus precluding semantic processing.
Nitrogen (N) deposition to soils is globally rising, but its effect on soil organic carbon (SOC) turnover is still uncertain. Moreover, common theories of stoichiometric decomposition and microbial N ...mining predict opposing effects of N supply on SOC turnover. We hypothesized that the effect of N deposition on SOC turnover depends on initial soil nutrient conditions. Thus, we sampled tropical forests and rubber gardens with pronounced gradients of nutrient availability from the topsoil to the deep subsoil (up to 400 cm) and measured substrate-induced respiration (SIR) for 30 days in four treatments (C, CN, CP, CNP additions). A natural 13C abundance approach was conducted to quantify priming effects (PE) of the added C on SOC mineralization. For this purpose we assessed the 13CO2 isotope composition after adding a C4 sugar to the C3 soil; to correct for isotopic fractionation a treatment with C3 sugar additions served as control. We found that nutrient additions to topsoil did neither alter cumulative CO2 release within 30 days (SIRacc) nor PE (PE = 1.6, i.e., sugar additions raised the release of SOC-derived CO2 by a factor of 1.6). In the upper subsoil (30–100 cm), however, both CN and CP additions increased SIRacc (by 239% and 92%, respectively) and the PE (PE = 5.2 and 3.3, respectively) relative to the treatments that received C only (PE = 1.7), while CNP additions revealed the largest increase of SIRacc (267%) and PE (PE = 6.0). In the deep subsoil (>130 cm depth), only the CNP addition consistently increased SIRacc (by 871%) and PE (PE = 5.2) relative to only C additions (PE = 2.0). We conclude that microbial activity was not limited by nutrients in the topsoil but was co-limited by both N and P in the subsoil. The results imply that microbes mine nutrients from previously unavailable pools under the conditions that 1) deficiency actually exists, 2) co-limitation is alleviated, and 3) nutrient reserves are present. Yet, as opposed to microbial nutrient mining theories, we showed that the subsoil PE is highest when nutrient supply matches microbial demand. As a result also N deposition might exert variable effects on SOC turnover in tropical soils: it might have no effect in nutrient-rich topsoils and in co-limited subsoils without P reserves but might increase SOC turnover in co-limited subsoils with potentially acquirable P reserves.
•Microbes are able to compensate for single nutrient deficiency by N or P mining.•Nutrient mining is constrained by co-limitation or absence of nutrient reserves.•Priming effects are largest in subsoils when nutrient supply matches microbial demand.•Soil nutrient conditions regulate the effect of N deposition on SOC turnover.
Class-switch recombination (CSR) is a DNA recombination process that replaces the immunoglobulin (Ig) constant region for the isotype that can best protect against the pathogen. Dysregulation of CSR ...can cause self-reactive BCRs and B cell lymphomas; understanding the timing and location of CSR is therefore important. Although CSR commences upon T cell priming, it is generally considered a hallmark of germinal centers (GCs). Here, we have used multiple approaches to show that CSR is triggered prior to differentiation into GC B cells or plasmablasts and is greatly diminished in GCs. Despite finding a small percentage of GC B cells expressing germline transcripts, phylogenetic trees of GC BCRs from secondary lymphoid organs revealed that the vast majority of CSR events occurred prior to the onset of somatic hypermutation. As such, we have demonstrated the existence of IgM-dominated GCs, which are unlikely to occur under the assumption of ongoing switching.
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•Germline transcripts peak prior to GC formation and rapidly decline in GCs•IgM-dominated clones are found in late GCs, arguing against ongoing Ig switching•CSR largely ceases upon the onset of somatic hypermutation•CSR decline due to low GLT and APE1 expression is possibly orchestrated by BCL6
Germinal centers (GCs) have long been considered sites in which Ig class-switch recombination (CSR) is favored. Roco et al. show that CSR occurs during the initial T cell:B cell interaction prior to GC formation and rapidly declines as B cells differentiate into GC cells and somatic hypermutation commences.
The subcellular basis of seed priming Varier, Anuradha; Vari, Alice Kuriakose; Dadlani, Malavika
Current science (Bangalore),
08/2010, Letnik:
99, Številka:
4
Journal Article
Recenzirano
Seed priming is a commercially used technique for improving seed germination and vigour. It involves imbibition of seeds in water under controlled conditions to initiate early events of germination, ...followed by drying the seed back to its initial moisture content. This review article summarizes the recent information available on the various subcelluar processes associated with priming which lead to seed enhancement. The paper discusses the role of synthesis of specific proteins in response to priming. The effect of priming on DNA repair, gene expression and synthesis of new message and protein synthesizing machinery are included. The enhancement in the energy metabolism of the cell by priming and the effect of priming in advancing and synchronizing the stage of the cell cycle are discussed. The article also includes information on the role of priming in specific cases, such as alleviation of dormancy in thermosensitive crops which require ethylene. The relationship between seed longevity and priming and methods to prolong longevity, wherever required after priming and the role of desiccation-related proteins, which accumulate during these treatments are also discussed. An illustration summarizing the information on all the metabolic processes which could possibly contribute towards the enhancement in seed performance achieved by priming is included. The paper identifies areas where information is lacking and potential for more in-depth research exists.
The (latest) crisis in confidence in social psychology has generated much heated discussion about the importance of replication, including how it should be carried out as well as interpreted by ...scholars in the field. For example, what does it mean if a replication attempt "fails"-does it mean that the original results, or the theory that predicted them, have been falsified? And how should "failed" replications affect our belief in the validity of the original research? In this paper, we consider the replication debate from a historical and philosophical perspective, and provide a conceptual analysis of both replication and falsification as they pertain to this important discussion. Along the way, we highlight the importance of auxiliary assumptions (for both testing theories and attempting replications), and introduce a Bayesian framework for assessing "failed" replications in terms of how they should affect our confidence in original findings.
Rule violations have usually been studied from a third-person perspective, identifying situational factors that render violations more or less likely. A first-person perspective of the agent that ...actively violates the rules, on the other hand, is only just beginning to emerge. Here we show that committing a rule violation sensitises towards subsequent negative stimuli as well as subsequent authority-related stimuli. In a Prime-Probe design, we used an instructed rule-violation task as the Prime and a word categorisation task as the Probe. Also, we employed a control condition that used a rule inversion task as the Prime (instead of rule violations). Probe targets were categorised faster after a violation relative to after a rule-based response if they related to either, negative valence or authority. Inversions, however, primed only negative stimuli and did not accelerate the categorisation of authority-related stimuli. A heightened sensitivity towards authority-related targets thus seems to be specific to rule violations. A control experiment showed that these effects cannot be explained in terms of semantic priming. Therefore, we propose that rule violations necessarily activate authority-related representations that make rule violations qualitatively different from simple rule inversions.
Verbs that are similar in meaning tend to occur in the same syntactic structures. For example, give and hand, which denote transfer of possession, both appear in the prepositional-object ...construction: “The child gave/handed the ball to the dog.” We can call the child a “giver” in one case and a “hander” in the other, or we can refer to her more generally as the agent, or doer of the action. Similarly, the dog can be called the recipient, and the ball, the theme. These generalized notions of agent, recipient, and theme are known as thematic roles. An important theoretical question for linguists and psycholinguists is what the set of thematic roles is. Are there a small number of very broad roles, perhaps with each one mapping onto a single canonical syntactic position? Or are there many distinct roles, several mapping to the same syntactic position but conveying subtly different meanings? We investigate this question across eleven structural priming experiments on Amazon Mechanical Turk (total N = 2914), asking whether speakers treat the thematic roles recipient and destination (i.e., location or spatial goal) as interchangeable, suggesting the broad role of goal, or distinct, suggesting two separate roles. To do so, we look for priming between dative sentences (e.g., “The man gave the ball to the dog”), which have a recipient role (dog), and locative sentences (e.g., “The man loaded hay onto the wagon”), which instead have a destination role (wagon). Our pattern of findings confirms that thematic role mappings can be primed independent of syntactic structure, lexical content, and animacy. However, we find that this priming does not extend from destinations to recipients (or vice versa), providing evidence that these two roles are distinct.
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