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21.
22.
Rathindra Nath Mandal Kuldeep Kumar Utkal Laxmi Mohanty & Prem Kumar Meher 《Aquaculture Research》2007,38(13):1364-1369
This study examined the food organisms found in the gut of freshwater mussels, Lamellidens marginalis L. A total of 34 taxa of food organisms were recorded, out of which 30 taxa belonged to phytoplankton and four taxa to zooplankton. Both the groups comprised three families each: Cyanophyceae (blue‐green algae), Chlorophycea (green algae) and Bacillariophyceae (diatoms) constituted phytoplankton, whereas Euglenaceae, Chlamydodontidae and Brachionidae belonged to zooplankton. The total number of frequencies of phytoplankton (n=537) were almost nine times more than that of zooplankton (n=60). When blue‐green algae, green algae, diatoms and zooplankton (all the three families together) were tested for significant difference (P<0.05) following Duncan's multiple range test, the result showed only two groups. Blue‐green algae, green algae and zooplankton were not significantly different (P<0.05), forming group A, whereas diatoms were significantly different from others, forming group B. The present study showed that the maximum number of organisms that mussels feed upon belong to green algae, followed by diatoms, blue‐green algae and few taxa of zooplankton. 相似文献
23.
K. G. Mandal K. M. Hati A. K. Misra K. K. Bandyopadhyay M. Mohanty 《Journal of Agronomy and Crop Science》2005,191(6):416-425
Increasing production of wheat from a limited water supply can result from efficient irrigation and nutrient management. A 3‐year field experiment was conducted at the Indian Institute of Soil Science, Bhopal, to study the growth, yield, seasonal evapotranspiration (ET) and water use efficiency (WUE), and the water–yield relationship of wheat in a soybean–wheat cropping system on vertisols. Three levels of irrigation, viz. I0, no post‐sowing irrigation; I1, two irrigations [crown root initiation (CRI) and flowering stage]; and I2, three irrigations (CRI, maximum tillering and flowering stage) and three nutrient management treatments, viz. F0, control (without fertilizer/manure); F1, 100 % NPK (100–21.5–24.9 kg ha?1); and F2, 100 % NPK + farmyard manure (FYM‐10 t ha?1) were tested in a split‐plot design with three replication. It has been established (through anova ) that the year effect was rather negligible and the interaction effects of irrigation and nutrient management on the growth parameters, ET, yield components, yield and WUE were significant. Plant height, progressive leaf area index, dry matter accumulation and crop growth rate were higher in I2F2, and I2F1 and I1F2 were statistically at par. The seasonal ET increased significantly with the increase in water supply in every nutrient treatment and it was highest in I2F2 and lowest in I0F0. The highest grain yield was obtained in I2F2; and a similar yield was recorded in I3F1 and I2F2. This shows a strong interaction effect between irrigation and nutrients. Yield components, viz. number of ears m?2, number of grains ear?1 and 1000‐grain weight were significant. The higher number of ears m?2 containing greater number of grains with relatively heavier weights appeared to have contributed to the higher yield in I1F2, I2F1 and I2F2. The highest WUE obtained in I0F2 did not correspond to the highest yield and maximum ET, but a WUE of 10.43 kg ha?1 mm?1 in the I2F2 combination corresponded with the highest yield and the seasonal ET requirement was 391.8, which was 137 % greater than the water use at maximum WUE. The ET–grain yield relationship was linear, with a lowest regression slope (i.e. marginal WUE) and elasticity of water production (Ewp) in F0 and a considerably higher slope and Ewp in F1 and F2. As the Ewp is positive and close to one in 100 % NPK treatment, the scope of improving WUE and yield with only inorganic fertilizer is very little, and relatively greater scope exists in the integrated management of organic manure and inorganic fertilizer. The results suggest that integrated nutrient management (100 % NPK + FYM) in conjunction with three irrigations maximized yield of wheat with concomitant improvement in ET and WUE under limited water availability. 相似文献
24.
R. K. Ghosh Bikash Kumar Mandal B. N. Chatterjee 《Journal of Agronomy and Crop Science》1991,167(4):221-228
A number of field experiments were conducted at the Viswavidyalaya Research Farm during 1984–85 to 1986–87 to study the effects of five growth regulators viz. Miraculan (a triacontanol based growth stimulant), Nutron (1-triacontanol growth stimulant), Planofix ( α -napthylacetic acid), Paras or Mixtalol (Higher alcoholic carbon compounds) and N-triacontanol on productivity of five different major oilseed crops viz. rapeseed ( Brassica campestris L. var. yellow sarson), mustard ( Brassica juncea L. Czern and Coss), sesame ( Sesamum indicum L.), linseed ( Linum usitatissimum L.) and safflower ( Carthemus tinctorius L.). Results showed the positive influence of growth regulators on the productivity of crops (10–40 % increase in yield); however the influence was not consistent over the years. N-triacontanol when tried on mustard only improved the grain yield significantly, more so when applied with paras or planofix, sesame was most influenced by spraying planofix and paras. Nutron favourably influenced safflower and linseed. The test weight of grains followed by the number of pods/plant were influenced most by the application of growth regulators. Inconsistency in results over the years, however, need further investigations on the timing of spraying. 相似文献
25.
26.
Chanda D Debnath SC Das SK Mandal TK Bhattacharyya A Choudhury A Chakraborty AK 《Journal of agricultural and food chemistry》2004,52(24):7377-7381
Disposition kinetic behavior and metabolism studies of metamitron and its metabolite in terms of the parent compound were carried out in black Bengal goats after a single oral administration of a nontoxic oral dose at 30 mg kg(-1) of body weight. Metamitron was detected in the blood sample at 5 min (2.23 +/- 0.04 microg mL(-1)), maximum at 1 h (3.43 +/- 0.02 microg mL(-1)) and minimum at 12 h (0.41 +/- 0.01 microg mL(-1)), after a single oral administration. Metabolite [3-methyl-6-phenyl-1,2,4-triazin-5(4H)-one] in terms of the parent compound was detected in the blood sample at 5 min (0.47 +/- 0.006 microg mL(-1)), maximum at 6 h (5.12 +/- 0.02 microg mL(-1)) and minimum at 96 h (1.06 +/- 0.016 microg mL(-1)), after a single oral administration. The t(1/2 K) and Cl(B) values of metamitron were 3.63 +/- 0.05 h and 1.36 +/- 0.016 L kg(-1) h(-1), respectively, whereas the t(1/2K)(m) and Cl(B)(m) values of the metabolite were 38.15 +/- 0.37 h and 0.091 +/- 0.001 L kg(-1) h(-1), respectively, which suggested long persistence of the metabolite in blood and tissues of goat. Metamitron was excreted through feces and urine for up to 48 and 72 h, whereas the metabolite was excreted for up to 168 and 144 h, respectively. Metabolite alone contributed to 96 and 67% of combined recovery percentage of metamitron and metabolite against the administered dose in feces and urine of goat, respectively. All of the goat tissues except lung, adrenal gland, ovary, testis, and mammary gland retained the metabolite residue for up to 6 days after administration. 相似文献
27.
Influence of tillage practices and nutrient management on crack parameters in a Vertisol of central India 总被引:5,自引:0,他引:5
K. K. Bandyopadhyay M. Mohanty D. K. Painuli A. K. Misra K. M. Hati K. G. Mandal P. K. Ghosh R. S. Chaudhary C. L. Acharya 《Soil & Tillage Research》2003,71(2):133-142
The frequency, size and rate of development of cracks influence the transport of water, nutrients and gases in the soil profile and plant growth processes in Vertisols. Despite their importance, studies on characterising cracks in Vertisols of India are limited. This study attempts to evaluate the influence of different tillage practices, nutrient management and cropping systems on cracking behaviour of a Vertisol in central India. The length, depth, width, area and volume of cracks were recorded after the harvest of the wet season crops, i.e. soybean (Glycine max L.) and rice (Oryza sativa L.) from three ongoing tillage experiments with three different cropping systems, i.e. soybean–wheat (Triticum aestivum L.), soybean–linseed (Linum usitatissimum L.) and rice–wheat. The results revealed that all the crack parameters were significantly negatively correlated with the water content of the 0–15 cm soil layer and, crack width and crack volume were significantly positively correlated with the bulk density of the 0–15 cm soil layer. Gravimetric water content and bulk density of the 0–15 cm soil layer together explained 79% variation in the crack volume. The crack volume was significantly negatively correlated (r=0.86,P=0.01) with the root length density of the previous soybean crop. Rice grown under puddled condition significantly enhanced different crack parameters viz., length, depth, width, surface area and volume of the cracks over nonpuddled direct seeded rice. Sub-soiling practised in soybean under the soybean–linseed system significantly reduced the width, depth, length and surface area of cracks by 12.5, 10, 5 and 12%, respectively, over conventional tillage. No tillage practised in soybean under soybean–wheat system resulted in significant increase in width, depth and volume of the cracks but decrease in length and surface area of cracks over conventional tillage and mould board tillage practice. Application of manure reduced the magnitude of different crack parameters in soybean–linseed cropping system. Thus cracking in Vertisols can be favourably managed by the selection of proper tillage practice, cropping system and organic manure amendments. 相似文献
28.
Soil infiltration, runoff and sediment yield from a shallow soil with varied stone cover and intensity of rain 总被引:6,自引:0,他引:6
Uttam Kumar Mandal K. V. Rao P. K. Mishra K. P. R. Vittal K. L. Sharma B. Narsimlu & K. Venkanna 《European Journal of Soil Science》2005,56(4):435-443
Stones on the surface of the soil enhance infiltration and protect the soil against erosion. They are often removed in modern mechanized agriculture, with unfortunate side‐effects. We evaluated experimentally the influence of surface stones on infiltration, runoff and erosion under field conditions using a portable rainfall simulator on bare natural soil in semi‐arid tropical India, because modernization and mechanization often lead to removal of these stones in this region. Four fields with varied cover of stones from 3 to 65% were exposed to three rainfall intensities (48.5, 89.2 and 136.8 mm hour?1). Surface stones retarded surface runoff, increased final infiltration rates, and diminished sediment concentration and soil loss. The final infiltration ranged from 26 to 83% of rainfall when the rainfall intensity was 136.8 mm hour?1. The reduction in runoff and soil erosion and increase in infiltration were more pronounced where stones rested on the soil surface than where they were buried in the surface layer. The sediment yield increased from 2 g l?1 for 64.7% stone cover with rainfall of 48.5 mm hour?1 to 70 g l?1 for 3.5% stone cover with rain falling at 136.8 mm hour?1. The soil loss rate was less than 2 t ha?1 hour?1 for the field with stone cover of 64.7% even when the rainfall intensity was increased to 136.8 mm hour?1. The effects of stones on soil loss under the varied rainfall intensities were expressed mathematically. The particles in the sediment that ran off were mostly of silt size. 相似文献
29.
A greenhouse pot experiment was conducted to study the effect of application of three levels of phosphorus (0, 50 and 100 ppm) and three levels of zinc (0, 5 and 10 ppm) in all possible combinations on yield and tissue concentrations of zinc, copper, iron and manganese by rice at two different growth stages (35 and 90 days after transplantation). The results showed that application of both phosphorus and zinc increased the dry matter yield of shoot and root at both the growth stages. Phosphorus or zinc application was found to influence the concentration of zinc, copper, iron and manganese in shoot and in root but these influences varied with the growth stages of the plant as well as with the level of zinc and phosphorus application. The results further showed that phosphorus or zinc application influenced the absorption of zinc/phosphorus, iron, manganese and copper by rice plants and their translocation from root to shoot. Such effects were found to be more prominent at early growth stage than at late growth stage of the plants. 相似文献
30.
K. Abirami Anjali Sharma Jatindra Nath Samanta V. S. Rana Kunal Mandal 《Phytoparasitica》2012,40(5):445-450
Mamejvo (Enicostemma axillare Raynal) is a perennial herb with diversified health benefits. It was found to be affected by a witches?? broom disease under the field conditions at Anand, Gujarat, India. Affected plants were 53.33% reduced in height due to shortened internodes, leading to typical witches?? broom symptoms. Flower size was reduced significantly in the affected plants compared with the healthy ones and their petal color gradually turned green (virescence). Affected plants produced 2.5 times more dry herbage than the normal plants but with less active ingredient (swertiamarin). Symptomatic plants died early while root suckers from such plants failed to establish after transplanting. DAPI stained transverse sections of affected shoot tips showed the presence of discrete greenish fluorescence in the phloem cells under UV light. Amplification of 1.2?kb phytoplasma specific rDNA fragment from diseased tissue confirmed the presence of the pathogen. Further characterization of the pathogen through virtual rDNA?CRFLP pattern and rDNA sequence based phylogeny suggested that the pathogen, Enicostemma witches?? broom phytoplasma, belonged to 16SrII?CC group of ??Ca Phytoplasma aurantifolia??. 相似文献