108 research outputs found

    Performance of sequential herbicides to control weeds in direct seeded rice

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    Direct seeded rice is an emerging production technology in India due to less requirement of water, labour and capital input initially. But direct seeded rice face severe infestation of weeds. A field experiment was conducted during the kharif 2012 at Students’ Farm of College of Agriculture, CCS Haryana Agricultural University; Kaul campus (Kaithal) to study the performance of sequential application of herbicides on weed flora in direct seeded rice. The herbicidal treatments included two pre emergence herbicides i.e. pendimethalin 1000 g/ha and oxadiargyl 100 g/ ha and four post emergence herbicides (bispyribac sodium 25 g/ha, fenoxaprop 67 g/ha, ethoxysulfuron 18.75 g/ha and metsulfuron methyl 10% + chlorimuron ethyl 10% WP ready mix (Almix) 4 g/ha). Weed free and weedy check were also included. The results showed that grasses were the dominant weed flora (49 %) followed by sedges (34%) and broad leaf weeds (17%).Sequential application of pendimethalin 1000 g/ha fb bispyribac sodium 25 g/ha and metsulfuron methyl + chlorimuron ethyl RM (Almix) 4 g/ha gave significantly lower weed density (p=0.05) and higher weed control efficiency which resulted in more number of effective tillers (209.3), filled grains/panicle (83.7) and grain yield (3.97 t/ha)

    Integrated weed management in direct seeded rice in Trans Indo-Gangetic plains of India- A review

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    In the Indo-Gangetic Plains (IGP) of India, rice (Oryza sativa L.) is taken by conventional tilled puddled transplanted (CT-PTR) method. CT-PTR requires a lot of water (2000-2500 mm) which comes mainly from groundwater. Due to declining water table and changing climate, the sustainability of CT-PTR rice is under immense pressure. The alternative to CT-PTR could be direct seeded rice (DSR) which requires less water, labor, initial cost and energy than CT-PTR. But direct seeded rice is heavily infested with weeds which cause severe loss to the grain yield. Thus, the success of aerobic rice depends on effective and timely weed control. As a single weed control method may not be successful on a long term basis, weed problem in direct seeded rice needs to be solved by integrated approach. Integrating cultural, mechanical and chemical methods along with highly competitive cultivars with effective allelopathic properties, effective weed management on long term sustainable basis can be achieved

    The evolution and impact of 3000 M_\odot stars in the early Universe

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    We present evolutionary models of massive, accreting population III stars with constant and variable accretion rates until the end of silicon burning, with final masses of 1000 - 3000 Msol. In all our models, after the core-hydrogen-burning phase, the star expands towards the red side of the Hertzsprung-Russell diagram is where it spends the rest of its evolution. During core helium burning, the models exhibit an outer convective envelope as well as many large intermediate convective zones.These intermediate zones allow for strong internal mixing to occur which enriches the surface in helium. The effect of increasing metallicity at a constant accretion rate of 10^{-3} Msol/yr shows an increase in the lifetime, final mass and distribution of helium in the envelope. Our fiducial model with mass of 3000 Msol has a final surface helium abundance of 0.74 and 9% of its total mass or 50% of the core mass, has a value of Gamma1 < 4/3 at the end of core silicon burning. If the collapse of the core is accompanied by the ejection of the envelope above the carbon-oxygen core, this could have a significant impact on the chemical evolution of the surroundings and subsequent stellar generations. The model has a final log(N/O) ~ 0.45, above the lower limit in the recently detected high-redshift galaxy GN-z11. We discuss the impact of a single 3000 Msol star on chemical, mechanical and radiative feedback, and present directions for future work.Comment: Accepted for publication in A&

    Influence of different transplanting date and weed management practices on yield and quality of basmati rice (Pusa Basmati-1509)

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    A field experiment was conducted during kharif 2014 at students’ farm of Chaudhary Charan Singh Haryana Agricultural University, college of agriculture, Kaul (Kaithal). The experiment consisted of four transplanting dates (June 15, July 5, July 25 and August 15) in main plots and six weed control treatments in sub plots treatments consisted of pre-emergence application of pretilachlor, oxadiargyl alone and sequential application of pre and post emergence herbicides viz., pretilachlor fb bispyribac, oxadiargyl fb bispyribac, weed free check and unweeded check. Based on research investigation it was observed that early transplanting dates (June 15 and July 5) produced taller plant, higher tillers/m2 and crop dry matter accumulation at all growth stages. Early transplanting produced significantly higher number of effective tillers/m2 (263) along with higher number of filled grain/ panicle (85) than delayed planting (July 25 and August 15). The 1000-grain weight was not affected by time of transplanting. The highest grain yield (4363 kg/ha) was recorded under June 15 transplanting which was statistically at par to the grain yield (4058 kg/ha) obtained under July 5 transplanting. Among the weed management practices tried, weed free check resulted in the highest values of plant height (104.2 cm), tillers/m2 (305), crop dry matter accumulation (964 g/ m2), effective tillers/m2 (271), grains length (8.5 cm), filled grains/panicle (86.3) as well as grain (4516 kg/ha) and straw yield (5506 kg/ha) which were however, comparable to pre-emergence application of oxadiargyl followed by bispyribac-sodium applied at 25 DAT and pretilachlor followed by bispribac-sodium at 25DAT

    Lessons learned from performance of students of Pharmacology in self coded surprise test with negative marking.

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    Introduction: The present study aims to find the effect of instruction of negative marking in a self-coded MCQ examination on the performance of students in the subject of Pharmacology with respect to the raw score, correct score and negative score. Material and methods: This longitudinal study was conducted in the Department of Pharmacology, Rural Medical College, Loni. The Second MBBS students were exposed to a self-coded MCQ test twice by surprise. The first test (T1) was given without instructions of negative marking, while during the second test (T2) instructions for negative marking were given. The parameters of the raw score, negative score, corrected score and number of students who did not attempt respective MCQs were calculated. The number of students passing with modified Minimum Passing Level was calculated was compared with conventional Minimum Passing Level. Results: Sixty-seven students participated in the study. There was a statistically significant decrease in the raw score in the T2, while the increase in the negative score when compared with T1. The number of non-attempted questions was increased in T2. There was a statistically significant difference in the number of students passed with respect to raw score in T1 and T2, while no such difference was seen with respect to Negative score and Corrected score. Conclusion: The Corrected score and Negative score are not affected by the minimum passing level, indicating a better parameter of scoring than the raw score. Hence, the use of Negative score or Corrected score should be encouraged than the use of conventional Raw score. Keywords: Minimum Passing Level, Negative Marking, MCQ, Corrected score, Pharmacology, Formative assessment, surprise test, self-coded test

    Numerical Simulation for a Multidimensional Fourth-Order Nonlinear Fractional Subdiffusion Model with Time Delay

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    The purpose of this paper is to develop a numerical scheme for the two-dimensional fourth-order fractional subdiffusion equation with variable coefficients and delay. Using the L2 − 1σ approximation of the time Caputo derivative, a finite difference method with second-order accuracy in the temporal direction is achieved. The novelty of this paper is to introduce a numerical scheme for the problem under consideration with variable coefficients, nonlinear source term, and delay time constant. The numerical results show that the global convergence orders for spatial and time dimensions are approximately fourth order in space and second-order in time. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Acknowledgments: M.A.Z. wishes to acknowledge the support of Nazarbayev University Program 091019CRP2120 and the partial support of the Science Committee of the Ministry of Education and Science of the Republic of Kazakhstan (Grant “Dynamical Analysis and Synchronization of Complex Neural Networks with Its Applications”). M.A.Z. wishes also to acknowledge the financial support of the National Research Centre of Egypt (NRC)

    The evolution and impact of 3000 M_\odot stars in the early Universe

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    peer reviewedWe present evolutionary models of massive, accreting population III stars with constant and variable accretion rates until the end of silicon burning, with final masses of 1000 - 3000 Msol. In all our models, after the core-hydrogen-burning phase, the star expands towards the red side of the Hertzsprung-Russell diagram is where it spends the rest of its evolution. During core helium burning, the models exhibit an outer convective envelope as well as many large intermediate convective zones.These intermediate zones allow for strong internal mixing to occur which enriches the surface in helium. The effect of increasing metallicity at a constant accretion rate of 10^{-3} Msol/yr shows an increase in the lifetime, final mass and distribution of helium in the envelope. Our fiducial model with mass of 3000 Msol has a final surface helium abundance of 0.74 and 9% of its total mass or 50% of the core mass, has a value of Gamma1 < 4/3 at the end of core silicon burning. If the collapse of the core is accompanied by the ejection of the envelope above the carbon-oxygen core, this could have a significant impact on the chemical evolution of the surroundings and subsequent stellar generations. The model has a final log(N/O) ~ 0.45, above the lower limit in the recently detected high-redshift galaxy GN-z11. We discuss the impact of a single 3000 Msol star on chemical, mechanical and radiative feedback, and present directions for future work

    Extra-short-duration pigeonpea for diversifying wheat-based cropping systems in the sub-tropics

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    The performance of newly developed extra-short-duration pigeonpea (Cajanus cajan) genotypes and traditional short-duration pigeonpea cultivars was compared in rotation with wheat in on-farm trials conducted in 1996–97 and 1997–98 in Sonepat (28° N) district in Haryana, and in 1996–97 at Ludhiana (30° N) district in Punjab, India. At both locations, a wheat crop (Triticum aestivum cv. HD 2329) followed pigeonpea. At Sonepat, an indeterminate extra-short-duration genotype ICPL 88039 matured up to three weeks earlier, yet gave 12% higher yield (1.57 t ha−1) and showed less susceptibility to borer damage than did the short-duration cv. Manak. At Ludhiana, extra-short-duration pigeonpea genotypes, ICPL 88039, ICPL 85010 and AL 201 gave similar grain yields to the short-duration T 21 in spite of maturing three to four weeks earlier. Yields of wheat crops following extra-short-duration genotypes were up to 0.75 t ha−1 greater at Sonepat and up to 1.0 t ha−1 greater at Ludhiana. The results of the study provide empirical evidence that extra-short-duration pigeonpea genotypes could contribute to higher productivity of pigeonpea–wheat rotation systems. Most of the farmers who grew on-farm trials in Sonepat preferred extra-short-duration to short-duration pigeonpea types for their early maturity, bold seed size, and the greater yield of the following wheat crop

    An ethnomedicinal survey of traditionally used medicinal plants from Charkhi Dadri district, Haryana: an attempt towards documentation and preservation of ethnic knowledge

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    436-450Medicinal plants have remained an integral source of therapeutics for primary healthcare since antiquity. The information pertaining to usage of plants is either inherited from elders or acquired through trials or the experience of others but is not documented frequently. South Haryana is one such rich storehouse of ethnomedicinal knowledge. Hence, ethnomedicinally important plants from Charkhi Dadri district of Haryana state were documented in the present study. The data was collected through field surveys and in-depth interviews organized in the fields during the years 2018-19. Factor of informant consensus was also calculated. A total of 90 ethnomedicinal plants were identified, belonging to 41 families and 79 genera. Majority of plants were herbs (47.7%), followed by trees (30%). Leguminosae (10%) represented the maximum number of plants, followed by Solanaceae (6.6% each) and Amaranthaceae, Lamiaceae and Poaceae (5.5% each). A total of 64 ailments were reported to be treated traditionally by ethnomedicinal plants in the area. The most commonly treated diseases were menorrhagia, skin boils, typhoid, diabetes, piles and diarrhoea. It was observed that the majority of plants were used freshly to extract juice, followed by powder and decoction and rarely as tea or oil forms. The present study provides comprehensive ethnomedicinal data including vernacular and botanical names, names of the family, mode of preparation, administration and dosage of plant drugs and diseases treated. It was concluded that this region still possesses numerous useful ethnomedicinal knowledge and may contribute to further herbal drug development programs
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