ARTICLE Download: 9| View: 66| Comments: 0 | doi:10.20944/preprints201907.0207.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: crop intensification; energy balance; North East Hill Region; organic farming; soil health; water productivity
Online: 18 July 2019 (09:06:21 CEST)
Organic farming has positive, impact on environment, soil health, and healthy food quality. Worldwide demand for organic foods is increasing by leaps and bounds in recent years. The present investigation was undertaken during 2014 to 2018 to evaluate the effect of cowpea (Vigna unguiculata) co-culture with maize (Zea mays L.) on productivity enhancement over prevailing maize-fallow system, and to assess the feasibility of inclusion of short duration winter crops after maize with appropriate residue management practices on productivity and soil health. The experiment comprised of six cropping systems in main plot and three soil moisture conservation (SMC) measures options in sub plot. Results indicated that the inclusion of second crop in place of fallow and cowpea co-culture with maize increased average maize grain yield by 6.2 to 23.5% as compared to that of maize-fallow (MF). Use of maize stover mulch (MSM) + weed biomass mulch (WBM) increases maize grain yield by 19.1 and 6.5% over those of MSM and no mulch (NM), respectively. Various soil moisture conservation (SMC) measures had significant (p=0.05) effect on crop yields and water productivity. Double cropping system had significantly (p=0.05) higher amount of soil available NPK, soil organic carbon (SOC), microbial biomass carbon (MBC) and dehydrogenase activity (DHA) at 0-15 cm and at 15-30 cm depth than those under MF. The SWC measures of MSM+WBM had significantly higher available N, SOC, and MBC by 5.5, 4.8 and 8.1% than those under NM, respectively. Correspondingly, soils under MSM and MSM+WBM had 2.24 and 2.99% lower bulk density (ρb) in 0-15 cm and 2.21 and 2.94% lower ρb in 15-30 cm than that of NM. The energy use efficiency (EUE) was significantly higher under MCV (7.90%) over rest of the cropping sequences. MSM+WBM and MSM recorded 25.1 and 16.6% higher net energy over NM, respectively. The net return (INR 159.99×103/ha) and B:C ratio (2.86) were significantly higher with MCV system followed by MCR cropping sequence. MSM+WBM had significantly higher net return (INR 109.44×103/h), B:C ratio (2.46) over those under MSM (INR 97.6×103/h) and NM (INR 78.61×103/h). Overall the cowpea co-culture with maize and inclusion of short cycle winter crops along with MSM+WBM in maize-based cropping systems was found productive in terms of crop and water, profitable, energy efficient and sustained the soil health.
Tue, 16 July 2019
REVIEW Download: 207| View: 780| Comments: 0 | doi:10.20944/preprints201907.0196.v1
Subject: Biology, Physiology Keywords: Myalgic Encephalomyelitis, Chronic Fatigue Syndrome, ME/CFS, diagnosis, metabolism, mitochondria, inflammation, immune system, signaling, gut microbiota.
Online: 16 July 2019 (12:41:26 CEST)
The underlying molecular basis of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is not well understood. Characterized by chronic, unexplained fatigue, a disabling payback following exertion (“post-exertional malaise”) and variably presenting, multi-system symptoms, ME/CFS is a complex disease which demands concerted biomedical investigation from disparate fields of expertise. ME/CFS research and patient treatment have been challenged by the lack of diagnostic biomarkers and finding these is a prominent direction of current work. Despite these challenges, modern research demonstrates a tangible biomedical basis for the disorder across many body systems. This evidence is largely comprised of disturbances to immunological and inflammatory pathways, autonomic and neurologic systems, abnormalities in muscle and mitochondrial function, shifts in metabolism, and gut physiology or gut microbiome disturbances. It is possible that these threads are together entangled as parts of an underlying molecular pathology reflecting a far-reaching homeostatic shift affecting each of these systems. Due to the variability of non-overlapping symptom presentation or precipitating events such as infection or other bodily stresses, the initiation of body-wide pathological cascades with similar outcomes stemming from different causes may be implicated in the condition. Patient stratification to account for this heterogeneity is therefore one important consideration during exploration of potential diagnostic developments.
ARTICLE Download: 15| View: 106| Comments: 0 | doi:10.20944/preprints201907.0190.v1
Subject: Biology, Animal Sciences & Zoology Keywords: microbiome; metamorphosis; symbiosis; endopterygota
Online: 16 July 2019 (08:06:48 CEST)
Gut bacteria play a key role in insect fitness, but the changes in gut microbiome profile across developmental stages of holometabolous insects remains little explored. Understanding changes in the microbiome across life stages is an important step toward understanding the associated shifts in functional relationships and trade-offs. Here, we characterised the microbiome of larvae, pupae, and adults of the highly polyphagous fruit fly Bactrocera tryoni (Froggatt) (Diptera: Tephritidae) using next-generation sequencing. We sampled individuals from colonies that had been recently introduced to the laboratory environment from naturally infested fruits at generations one (‘G1’) and five (‘G5’). Alpha diversity increased across developmental stages at both G1 and G5, with maximum diversity in adults. Community composition changed across developmental stages and between generations. In G1, larval and pupal microbiomes were dominated by the genus Asaia whereas adult microbiomes were dominated by Enterobacter. In G5, larval and pupal microbiomes contained a high relative abundance of Asaia, but pupae also had a high relative abundance of Staphylococcus and Burkholderia, and there were no dominant patterns in adults. Our findings provide insights into the developmental stage-dependent microbiome associations of a polyphagous fly, and how host-symbiont interactions change at each life stage through the transition from nature to laboratory environments.
Mon, 15 July 2019
ARTICLE Download: 7| View: 123| Comments: 0 | doi:10.20944/preprints201907.0184.v1
Subject: Biology, Other Keywords: depression; nurturing; honest signaling; reproductive suppression; anthocyanins; hormesis
Online: 15 July 2019 (13:31:03 CEST)
Background: Solon (2019) introduced genetic bandwagoning in a very general sense: A variant sequentially 1) evaluates its holder’s quality and 2) induces its holder to relinquish resources if the holder’s quality is low. Here, I introduce a more complex form of bandwagoning in order to account for a series of phenomena considered “paradoxical” by scientists specializing in their literatures: a) depression, b) differential nurturing, c) honest signaling of quality, d) reproductive suppression, e) stress-induced anthocyanins, and f) hormesis. These literatures are characterized by the following findings: 1) Low-quality individuals incur a cost against reproductive success compared to higher-quality individuals. 2) Individuals not (yet) identified as low-quality incur a cost against their ability to survive predators and/or parasites compared to individuals that have already been identified as low-quality. 3) Females incur a cost against reproductive success compared to males. 4) Males incur a cost against their ability to survive predators and/or parasites compared to females. 5) If conditions are challenging, individuals gain in both reproductive success and their ability to survive predators and/or parasites compared to less challenging conditions; however, too-challenging conditions detract from both. For each literature, at least one of these findings is unaccommodated by existing theory when considered in the context of that literature. Despite existing theory, these patterns are remarkably persistent. Question: Can paradoxes fitting these patterns be explained by genetic bandwagoning theory? Conclusion: Here, reservation is introduced as a form of bandwagoning in which a bandwagoning variant induces its holder to reserve from (i.e., withhold) some of its ability to survive parasites or predators. Reservation would occur for the purpose of assessing a holder’s quality when conditions are sufficiently unchallenging that few individuals are chronically stressed, so it is otherwise difficult to evaluate a holder’s quality. If the holder is subsequently killed, wounded, or infected, then it is identified as lacking the quality that would allow its descendants to survive more challenging conditions. The holder loses some or all of its resources as a direct consequence of the very death, wounding, or infection that identified its low quality. That is, in reservation, the two steps of bandwagoning are accomplished simultaneously. (This way of bandwagoning is distinguished from when the two steps are accomplished sequentially, which is termed resonation.) Reservation shares numerous premises with Zahavi’s handicap principle. If conditions are challenging, individuals would downregulate reservation and also be less likely to forego resources through resonation (which accounts for (5)). Additionally, a bandwagoning variant would likely evolve to vary the reservation it induces from holder to holder as a hedge against the possibility that conditions suddenly turn severe before it can adjust the reservation. Individuals already identified as low-quality would downregulate reservation (which accounts for (2) above) and would instead forego resources through resonation (which accounts for (1)). Additionally, females would downregulate reservation (which accounts for (4)) and, as a consequence, surviving females are more likely than surviving males to forego resources through resonation (which accounts for (3)).