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31.
Kumar Rahul Das Munshi Anilabh Behera Tusar Kanti Jat Gograj Singh Choudhary Harshawardhan Talukdar Akshay Dash Prasanta Singh Deepak 《Genetic Resources and Crop Evolution》2022,69(5):1901-1917
Genetic Resources and Crop Evolution - In several regions of the world, low productivity in this crop is attributed to several factors including poor understanding of the genomic complexity of... 相似文献
32.
Effect of abiotic factors on understory community structures in moist deciduous forests of northern India 总被引:1,自引:0,他引:1
Ashish K. Mishra Soumit K. Behera Kripal Singh R. M. Mishra L. B. Chaudhary Bajrang Singh 《中国林学(英文版)》2013,15(4):261-273
Understory vegetation controls, in a significant way, the regeneration of overstory trees, carbon sequestration and nutrient retention in tropical forests. Development and organization of understory vegetation depend 3n climate, edaphic and biotic factors which are not well correlated with plant community structures. This study aimed to ~xplore the relationships between understory vegetation and abiotic factors in natural and planted forest ecosystems. A non-metric multidimensional scaling (NMS) ordination technique was applied to represent forest understory vegetation among five forest communities, i.e., a dry miscellaneous forest (DMF), a sal mixed forest (SMF), a teak plantation (TP), a low-land miscellaneous forest (LMF) and a savanna area (SAV) of the Katerniaghat Wildlife Sanctuary, located in northern India. Microclimatic variables, such as photosynthetically active radiation (PAR), air temperature (AT), soil Lemperature (ST), ambient atmospheric CO2 concentration, absolute air humidity (AH), physical and chemical soil ~roperties as well as biological properties were measured. Understory species were assessed via 100 random quadrats (5 m x 5 m) in each of the five forests in which a total of 75 species were recorded encompassing 67 genera from 37 families, consisting of 32 shrubs and 43 plant saplings. DMF was the most dense forest with 34,068 understory individuals per ha of different species, whereas the lowest understory population (13,900 per ha) was observed in the savanna. Ordination and correlation revealed that microclimate factors are most important in their effect compared to ~daphic factors, on the development of understory vegetation in the various forest communities in the north of India. 相似文献
33.
The adsorption capacity of pine tree leaves for removal of methylene blue (MB) from aqueous solution was investigated in a batch system. The effects of the process variables, such as solution pH, contact time, initial dye concentration, amount of adsorbent, agitation speed, salt concentration, and system temperature on the adsorption process were studied. The extent of methylene blue dye adsorption increased with increase in initial dye concentration, contact time, agitation speed, temperature, and solution pH but decreased with increased in amount of adsorbent and salt concentration. Equilibrium data were best described by both Langmuir isotherm and Freundlich adsorption isotherm. The maximum monolayer adsorption capacity of pine tree leaves biomass was 126.58?mg/g at 30?°C. The value of separation factor, R L , from Langmuir equation and Freundlich constant, n, both give an indication of favorable adsorption. The intrapartical diffusion model, liquid film diffusion model, double exponential model, pseudo-first and second order model were used to describe the kinetic and mechanism of adsorption process. A single stage bath adsorber design for the MB adsorption onto pine tree leaves has been presented based on the Langmuir isotherm model equation. Thermodynamic parameters such as standard Gibbs free energy (??G 0), standard enthalpy (??H 0), and standard entropy (??S 0) were calculated. 相似文献
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35.
The potential of alginate-coated chitosan microspheres to act as an antigen carrier through oral vaccination was explored in fish. Among different antigenic formulations such as antigen-loaded alginate-coated and alginate-uncoated chitosan microspheres, empty alginate-coated chitosan microspheres and free whole-cell antigen, only alginate-coated chitosan microspheres gave promising results for stimulating both adaptive and innate immune response up to 6 weeks of post-immunization. In addition, alginate-coated chitosan microspheres modulated antigen-release behavior, maintained structural integrity and stability and gave effective protection to antigens from acidic degradation in vitro for 12 h. However, none of these formulations tested in this study are effective for protecting fish against Aeromonas hydrophila infection under the conditions evaluated in the present work. The enhancement of the immune response observed with the antigen-loaded alginate-coated chitosan microspheres demonstrates its promising effect for oral antigen delivery in fish. 相似文献
36.
Pathogenic variability of different isolates of Colletotrichum falcatum Went. collected from six varieties: Co 419, CoC 671 (from Andhra Pradesh), Co 86032, Co87044, 89V74, and a local variety in Bhadrak (from Orissa) were established. Six red rot isolates were differentiated into four distinct pathotypes, viz., pathotype A - Cf 419 and Cf Bdkh; pathotype B - Cf 671; pathotype C - Cf 89V74 and pathotype D - Cf 86032, and Cf 87044. Pathotype A showed a susceptible reaction to Khakai, CoC 671, CoJ 64, and Co 419. Also pathotype B showed a susceptible reaction to Baragua, CoC 671, Co 997, CoJ 64, Co 1148, and Co 975, whereas pathotype C showed a susceptible reaction to CoC 671, Co 7717, Co 997, CoJ 64, Co 975, and Co 419. But pathotype D showed a susceptible reaction to CoC 671 and Co 997. Polymerase chain reaction (PCR) amplification and subsequent restricted fragment length polymorphism (RFLP) analysis of internal transcribed spacer region of ribosomal DNA (rDNA) of Cf 89V74, Cf 671 and Cf Vittal (C. falcatum isolate from Vittal, Karnatak) by four restriction enzymes, Alu I, Msp I, Rsa I, and Pvu II revealed two distinct groups viz.Group 1- Cf 89V74 and Cf Vittal; Group 2-Cf 671. Restriction enzymes Alu I, Msp I, Rsa 1, and Pvu II produced fragment lengths of 380, 520, 550, and 580 bp for Cf Vittal and Cf 89V74, whereas fragment lengths of 420, 370, 440, and 460 bp were observed in Cf 671, respectively. The present investigation with the red rot infected sugarcane samples clearly indicated the existence of two pathotypes viz., pathotype A and pathotype B in Andhra Pradesh and three pathotypes viz., pathotype A, pathotype C, and pathotype D in Orissa. Pathotype C (Cf 89V74) showed similar ITS-RFLP pattern in Cf Vittal which was isolated from Karnataka. 相似文献
37.
Alam Md. Ashraful Rahman Md. Mizanur Biswas Jatish Chandra Akhter Sohela Maniruzzaman M. Choudhury Apurba Kanti Jahan M. Abu Hena Sorwar Miah Md. Main Uddin Sen Ranjit Kamal M. Zia Uddin Mannan Md. Abdul Shiragi Humayun Kabir Kabir Wais Kalra Naveen 《Paddy and Water Environment》2019,17(4):677-688
Paddy and Water Environment - Rice-based cropping systems in Bangladesh have received little consideration of changing nitrogen (N) and carbon (C) in soil. Therefore, this study was conducted at... 相似文献
38.
In the present work, the effectiveness of physic seed hull, PSH (Jatropha curcas L.), as an alternative low-cost adsorbent for the removal of malachite green (MG) dye from simulated wastewater has been studied. It has been observed that PSH has remarkable adsorption capacity compared to granular activated carbon. The PSH adsorbent was characterized by SEM-EDX, BET, CHNS, zeta potential, and FTIR techniques. The adsorption behaviors such as adsorption kinetics, adsorption dynamics, and adsorption isotherms of PSH for the removal of MG dye from aqueous solution were studied in detail. The kinetic data fitted well with the pseudo second-order kinetic model for MG adsorption. Langmuir isotherm was found to be the model best fitted to describe the adsorption process. 相似文献
39.
本文对印度西部5种热带干落叶林中凋落物里生物元素的季节性变化和它们返回到新鲜叶中季节性变化进行研究。对5个树种:阿拉伯金合欢(Acacia nilotica L.)、金合欢(Acacia leucophloea Roxb.)、柚木(Tectonagrandis L.f.)、绒毛野独活(Miliusa tomentosa Roxb.)和紫矿(Butea mono-sperma Lain.)中凋落物的成熟叶、枝和再生部分的N、P、Ca、Mg、K和Na的浓度,以及老叶和幼叶中浓度间的关系进行调查。对这些树种的总干物质进行记录,并分析它们所含的N、P、Ca、Mg、K和Na的含量。其中阿拉伯金合欢叶子中N的含量最高,而金合欢的叶子里Ca和Mg含量最高。叶中含P最多的是阿托伯金合欢、金合欢和紫矿,而含P最少的是柚木和绒毛野独活。K和Na含量在这些树种中没有明显的区别。观察发现,N、P和K的浓度随季节变化大,但Ca和Mg则不然。唯有钾在所有树种中都是最稳定的,吸收N和P可以用于来年新叶的生长。从老叶和凋落物中吸收的营养会支持新叶的生长,并增加土壤的肥力。图1表4参30。 相似文献
40.
L. K. Bharathi Vinod A. D. Munshi T. K. Behera Shanti-Chandrashekaran J. J. Kattukunnel A. B. Das Vishalnath 《Euphytica》2010,176(1):79-85
Teasle gourd [Momordica subangulata Blume subsp. renigera (G. Don) de Wilde, 2n = 56] exhibits morphological characters found in both M. dioica (2n = 28) and M. cochinchinensis (2n = 28). Morphological analysis of M. subangulata subsp. renigera suggests an allopolyploid origin. We present evidence elucidating the genomic relationships between M. dioica, M. cochinchinensis and M. subangulata subsp. renigera. A triploid M. dioica × M. subangulata subsp. renigera hybrid had an average of 12.76 bivalents, 13.84 univalents and 0.88 trivalents at metaphase I, while the M. cochinchinensis × M. subangulata subsp. renigera hybrid had an average of 13.08 bivalents, 12.96 univalents and 0.96 trivalents. F1 hybrids of the two diploid species (M. dioica × M. cochinchinensis) showed an average of 9.12 bivalents and 9.76 univalents, suggesting that the genomes of these species are only partially
homologous. A higher number of bivalents in the triploid hybrids suggests that M. subangulata subsp. renigera is a segmental allopolyploid of M. dioica and M. cochinchinensis and that its genomes have diverged from the parental genomes. 相似文献