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K. K. Singh

Bio: K. K. Singh is an academic researcher from All India Institute of Medical Sciences. The author has contributed to research in topics: No-till farming & Tillage. The author has an hindex of 14, co-authored 19 publications receiving 593 citations. Previous affiliations of K. K. Singh include Indian Institutes of Technology & Asian Institute of Technology.

Papers
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Journal ArticleDOI
TL;DR: A 3-year field study was conducted to evaluate the effect of three tillage practices (conventional, zero and reduced/strip) with two nitrogen levels (120 and 150 kg N −1 ) applied in primary strips and three crop residue management practices (removal, burning and incorporation) in secondary strips in wheat after rice as mentioned in this paper.
Abstract: A 3-year field study was conducted to evaluate the effect of three tillage practices (conventional, zero and reduced/strip) with two nitrogen levels (120 and 150 kg N ha −1 ) applied in primary strips and three crop residue management practices (removal, burning and incorporation) in secondary strips in wheat after rice. Reduced tillage resulted in significantly higher overall mean wheat yield (5.10 Mg ha −1 ) compared to conventional (4.60 Mg ha −1 ) and zero tillage (4.75 Mg ha −1 ). Residue incorporation resulted in highest mean yield (5.86 Mg ha −1 ) during third year. Maximum mean yield (6.1 Mg ha −1 ) was obtained in reduced tillage followed by conventional tillage (5.8 Mg ha −1 ) under residue incorporation in third year. The weed dry weight recorded at 30 days after sowing was highest (0.3 Mg ha −1 ) under zero tillage and lowest under conventional tillage (0.16 Mg ha −1 ). Among crop residue management practices, the highest dry weight of weeds (0.22 Mg ha −1 ) was recorded under residue incorporation. The highest infiltration rate (1.50 cm h −1 ) was recorded in residue incorporation followed by residue burning (1.44 cm h −1 ) whereas; the lowest (0.75 cm h −1 ) in zero tillage. Soil bulk density was the highest (1.69 Mg m −3 ) under zero tillage and the lowest in residue incorporation (1.59 Mg m −3 ). There were no changes in soil available P and K after each crop sequence in relation to tillage practices during first 2 years. Higher organic carbon (5.1–5.4 g kg −1 ) was measured under zero tillage compared to other treatments. Residue incorporation increased soil organic carbon and available P while higher available K was monitored in burning treatment during the third year. These results suggest that reduced tillage and in situ incorporation of crop residues at 5 Mg ha −1 along with 150 kg N ha −1 were optimum to achieve higher yield of wheat after rice in sandy loam soils of Indo-Gangetic plains of India.

205 citations

Journal ArticleDOI
TL;DR: In this article, a "tilth index" based upon five soil physical properties was developed to quantify tilth, which ranges from zero for conditions unusable by the plant to one for a soil that is non-limiting for plant growth.
Abstract: Tilth is a qualitative term that describes the physical state of soil. There is need for a quantitative understanding of soil tilth to help scientists, engineers, and farmers better understand how to manage soil. A “tilth index” based upon five soil physical properties was developed to quantify tilth. Values of bulk density, cone index, aggregate uniformity coefficient, organic matter content, and plasticity index were used to calculate an index, that ranges from zero for conditions unusable by the plant to one for a soil that is nonlimiting for plant growth.

89 citations

Journal ArticleDOI
01 Jul 2017-Energy
TL;DR: A 16-year old field study in the Indo-Gangetic Plains (IGP) with different methods of rice cultivation viz., zero tillage (ZT), happy turbo seeder (HTS), bed planting (BP), reduced-tillage (RT), conventional sowing (CS), direct-sowing (DS), broadcast method of sowing(BS), manual transplanting (HT) and selected transplanting methods like, manual transplanter (MT) and mechanical transplter (MaT) was used to evaluate the energy input and GWP

76 citations

Journal ArticleDOI
TL;DR: Results indicated that tillage significantly decreased soil bulk density over the zero tillage system and available soil N, P and K contents were affected significantly due to seeding method and tillage after each cycle of rice–wheat sequence.
Abstract: A 3-year field study was conducted during 1998/99–2000/01 on the effect of tillage on crop growth, yield and nutrient use in wheat (Triticum aestivum L.) grown after different methods of rice (Oryza sativa L.) seeding. Treatments comprised three methods of rice seeding, viz. direct seeding (unpuddled), manual transplanting and mechanical transplanting by self-propelled rice transplanter as main plots and three tillage levels in wheat (conventional tillage (CT), reduced tillage (RT), zero tillage (ZT)) as subplots. Results indicated that tillage significantly decreased soil bulk density (1·59 Mg/m3) over the zero tillage system (1·69 Mg/m3). Greater root density in terms of root dry weight (7·50 Mg/20 cm row length) was recorded in CT and the lowest root dry weight (5·80 Mg/20 cm row length) was obtained in ZT during 2000/01. Significantly higher dry matter accumulation (254 g/m row) and leaf area index of wheat (3·04) were consistently recorded under direct seeding of rice, which was statistically different from the other methods of seeding adopted in the preceding rice crop. CT resulted in significantly higher dry matter (253 g/m row) and leaf area index of wheat (3·02) than RT and ZT respectively, during 2000/01. The highest mean yield of wheat (6·02 Mg/ha) was obtained in direct seeding of rice, followed by mechanical and manual transplanting. Among different tillage levels, CT recorded the highest mean yield of wheat (5·90 Mg/ha) followed by RT (5·82 Mg/ha) and ZT (5·40 Mg/ha). The yield reduction was in the order of 11·28 and 6·31% under ZT and RT, respectively. Soil chemical analysis showed that available soil N, P and K contents were affected significantly due to seeding method and tillage after each cycle of rice–wheat sequence. Significantly greater available soil N, P and K were recorded under direct seeding of rice followed by manual and mechanical transplanting. CT recorded significantly lower values of available soil N and higher values of soil P and K whereas ZT recorded higher values of available soil N and lower values of available soil P and K during the 3 years of study.

42 citations

Journal ArticleDOI
TL;DR: In this paper, an attempt has been made to relate transition temperature (Tc ) with spontaneous polarization (Ps ) for displacive ferroelectrics belonging to different families.
Abstract: An attempt has been made to relate transition temperature (Tc ) with spontaneous polarization (Ps ) for ‘Twenty Two’ displacive ferroelectrics belonging to different families. A possible Ps -Δz relation is predicted on the basis of our previously reported Tc -Δz relationship. It exhibits a fairly good agreement between experimental and theoretical results. A new classification of ferroelectrics has been proposed wherein the concept of ‘strong’ and ‘weak’ ferroelectrics is introduced.

34 citations


Cited by
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Journal ArticleDOI
TL;DR: The Mucorales are associated with angioinvasive disease, often leading to thrombosis, infarction of involved tissues, and tissue destruction mediated by a number of fungal proteases, lipases, and mycotoxins.
Abstract: The Zygomycetes represent relatively uncommon isolates in the clinical laboratory, reflecting either environmental contaminants or, less commonly, a clinical disease called zygomycosis. There are two orders of Zygomycetes containing organisms that cause human disease, the Mucorales and the Entomophthorales. The majority of human illness is caused by the Mucorales. While disease is most commonly linked to Rhizopus spp., other organisms are also associated with human infection, including Mucor, Rhizomucor, Absidia, Apophysomyces, Saksenaea, Cunninghamella, Cokeromyces, and Syncephalastrum spp. Although Mortierella spp. do cause disease in animals, there is no longer sufficient evidence to suggest that they are true human pathogens. The spores from these molds are transmitted by inhalation, via a variety of percutaneous routes, or by ingestion of spores. Human zygomycosis caused by the Mucorales generally occurs in immunocompromised hosts as opportunistic infections. Host risk factors include diabetes mellitus, neutropenia, sustained immunosuppressive therapy, chronic prednisone use, iron chelation therapy, broad-spectrum antibiotic use, severe malnutrition, and primary breakdown in the integrity of the cutaneous barrier such as trauma, surgical wounds, needle sticks, or burns. Zygomycosis occurs only rarely in immunocompetent hosts. The disease manifestations reflect the mode of transmission, with rhinocerebral and pulmonary diseases being the most common manifestations. Cutaneous, gastrointestinal, and allergic diseases are also seen. The Mucorales are associated with angioinvasive disease, often leading to thrombosis, infarction of involved tissues, and tissue destruction mediated by a number of fungal proteases, lipases, and mycotoxins. If the diagnosis is not made early, dissemination often occurs. Therapy, if it is to be effective, must be started early and requires combinations of antifungal drugs, surgical intervention, and reversal of the underlying risk factors. The Entomophthorales are closely related to the Mucorales on the basis of sexual growth by production of zygospores and by the production of coenocytic hyphae. Despite these similarities, the Entomophthorales and Mucorales have dramatically different gross morphologies, asexual reproductive characteristics, and disease manifestations. In comparison to the floccose aerial mycelium of the Mucorales, the Entomophthorales produce a compact, glabrous mycelium. The asexually produced spores of the Entomophthorales may be passively released or actively expelled into the environment. Human disease with these organisms occurs predominantly in tropical regions, with transmission occurring by implantation of spores via minor trauma such as insect bites or by inhalation of spores into the sinuses. Conidiobolus typically infects mucocutaneous sites to produce sinusitis disease, while Basidiobolus infections occur as subcutaneous mycosis of the trunk and extremities. The Entomophthorales are true pathogens, infecting primarily immunocompetent hosts. They generally do not invade blood vessels and rarely disseminate. Occasional cases of disseminated and angioinvasive disease have recently been described, primarily in immunocompromised patients, suggesting a possible emerging role for this organism as an opportunist.

1,332 citations

Journal ArticleDOI
TL;DR: In this paper, the authors focus on the current understanding of acute-on-chronic liver failure from the clinical, prognostic and pathophysiological perspectives and indicate potential biomarkers and therapeutic targets for intervention.

648 citations

Journal ArticleDOI
TL;DR: In this article, the authors trace the development of the concept of soil quality and explore the use of soil chemical and physical properties as determinants of forest soil quality, and present challenges and opportunities for forest soil scientists to play a relevant role in assessment and advancement of sustainable forest management by developing soil quality as an indicator of sustainability.

580 citations

Book ChapterDOI
TL;DR: In this article, the authors present an integrated package of technologies for dry-DSR, including the identification of rice traits associated with the attainment of optimum grain yield with dry seeding.
Abstract: Rice (Oryza sativa L.), a staple food for more than half of the world population, is commonly grown by transplanting seedlings into puddled soil (wet tillage) in Asia. This production system is labor-, water-, and energy-intensive and is becoming less profitable as these resources are becoming increasingly scarce. It also deteriorates the physical properties of soil, adversely affects the performance of succeeding upland crops, and contributes to methane emissions. These factors demand a major shift from puddled transplanting to direct seeding of rice (DSR) in irrigated rice ecosystems. Direct seeding (especially wet seeding) is widely adopted in some and is spreading to other Asian countries. However, combining dry seeding (Dry-DSR) with zero/reduced tillage (e.g., conservation agriculture (CA)) is gaining momentum as a pathway to address rising water and labor scarcity, and to enhance system sustainability. Published studies show various benefits from direct seeding compared with puddled transplanting, which typically include (1) similar yields; (2) savings in irrigation water, labor, and production costs; (3) higher net economic returns; and (4) a reduction in methane emissions. Despite these benefits, the yields have been variable in some regions, especially with dry seeding combined with reduced/zero tillage due to (1) uneven and poor crop stand, (2) poor weed control, (3) higher spikelet sterility, (4) crop lodging, and (5) poor knowledge of water and nutrient management. In addition, rice varieties currently used for DSR are primarily selected and bred for puddled transplanted rice. Risks associated with a shift from puddled transplanting to DSR include (1) a shift toward hard-to-control weed flora, (2) development of herbicide resistance in weeds, (3) evolution of weedy rice, (4) increases in soil-borne pathogens such as nematodes, (5) higher emissions of nitrous oxide—a potent greenhouse gas , and (6) nutrient disorders, especially N and micronutrients. The objectives of this chapter are to review (1) drivers of the shift from puddled transplanting to DSR; (2) overall crop performance, including resource-use efficiencies of DSR; and (3) lessons from countries where DSR has already been widely adopted. Based on the existing evidence, we present an integrated package of technologies for Dry-DSR, including the identification of rice traits associated with the attainment of optimum grain yield with Dry-DSR.

513 citations

Journal ArticleDOI
TL;DR: In this article, the authors describe the importance of plants and soil functions on carbon sequestration, review the mechanisms of SOC sequestration within aggregates under different vegetation and soil management practices, and explain methods of assessing distribution of organic matter in aggregates, and identify knowledge gaps with regards to SOC and soil structural dynamics.
Abstract: Soil and crop management practices have a profound impact on carbon (C) sequestration, but the mechanisms of interaction between soil structure and soil organic C (SOC) dynamics are not well understood. Understanding how an aggregate stores and protects SOC is essential to developing proper management practices to enhance SOC sequestration. The objectives of this article are to: (1) describe the importance of plants and soil functions on SOC sequestration, (2) review the mechanisms of SOC sequestration within aggregates under different vegetation and soil management practices, (3) explain methods of assessing distribution of SOC within aggregates, and (4) identify knowledge gaps with regards to SOC and soil structural dynamics. The quality and quantity of plant residues define the amount of organic matter and thus the SOC pool in aggregates. The nature of plant debris (C:N ratio, lignin content, and phenolic compound content) affects the rate of SOC sequestration. Mechanisms of interaction of aggregate dy...

503 citations