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51.
Suprakash Saha Monidipta Saha Amit Ranjan Saha Sabyasachi Mitra Surja Kumar Sarkar Ashesh Kumar Ghorai 《Journal of plant nutrition》2013,36(8):1191-1200
The interactive effect of potassium (K) and sulfur (S) fertilization on productivity and mineral nutrition of sunnhemp (Crotalaria juncea L.) was evaluated in a field experiment during 2008 and 2009 cropping seasons at Uttar Pradesh, India. Potassium and sulfur fertilizers increased fiber yield and nutrient uptake of sunnhemp. It was observed that an application of K and S at 40 kg ha?1 each significantly increased the total dry matter, fiber yield, and nutrient uptake of sunnhemp. The crop yield response to the added S was greater than for K and the nutrient use efficiency was also higher at lower levels of fertilizer addition. The increased levels of K and S improved the number of nodules and crude protein content of sunnhemp leaves. 相似文献
52.
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54.
Evaluation of pan coefficient for reference crop evapotranspiration for semi-arid region 总被引:1,自引:0,他引:1
Pan coefficient (K
pan) is the important factor for computation of reference evapotranspiration (ET
o
) from pan evaporation (E
pan). In this paper, the approaches proposed by Cuenca (Irrigation system design: an engineering approach. Prentice-Hall, Englewood
Cliffs, 1989), Snyder (J Irrig Drain Eng 118(6):977–980, 1992), Orang (Potential accuracy of the popular non-linear regression
equations for estimating pan coefficient values in the original and FAO-24 tables. Unpublished Report, Calif. Dept. of Water
Resources, Sacramento, 1998), Raghuwanshi and Wallender (J Irrig Drain Eng 118 (6):977–980, 1998) and Pereira et al. (Agric
Water Manage 76:75–82, 1995) were evaluated for a semi-arid region. By comparing with the FAO 56 Penman-Monteith (F-PM) method
the Snyder (J Irrig Drain Eng 118(6):977–980, 1992, 1992) approach was best suited for the semi-arid region. 相似文献
55.
Govind Pratap Rao Amar Bahadur Sukhen Chandra Das Hemavati Ranebennur Surabhi Mitra Manish Kumar Shailender Kumar 《Forest Pathology》2020,50(1)
Leaf yellowing symptoms were observed on Acacia mangium in the Sipahijala district of Tripura, India, during June 2017. Symptomatic and asymptomatic leaf samples (three of each) were collected from roadside trees of A. mangium for DNA extraction using the CTAB method. Amplicons of ~1.25 kb and ~480 bp were detected in all the symptomatic samples using the phytoplasma‐specific universal 16S rRNA and secA gene primers. Pair wise sequence analysis of 16S rRNA gene sequences, virtual RFLP and phylogenetic analysis revealed that the phytoplasma strain associated with A. mangium belonged to phytoplasma subgroup 16SrII‐C. This is the first report of an association between the 16SrII‐C subgroup and A. mangium leaf yellowing. 相似文献
56.
Age, growth and maturity data of the freshwater feather back Chitala chitala (Hamilton-Buchanan, 1822) were collected from ten different geographical locations. Out of ten populations, maximum 6+ ages were recorded from four river basins namely river Bhagirathi, Koshi, Saryu and Ganga and the back calculated lengths at 6+ ages ranged from 1033.36–1073.63 mm. In rest of the locations, however, only 3+ age classes were recorded. Specific rate of linear growth (Cl) and specific rate of weight increase (Cw) showed decreases except in two locations. The specific rate of linear growth (Cl) and the specific rate of weight increase (Cw) increased at 3+ age class in the river Bhagirathi. Among other growth parameters, three distinct life stages of C. chitala were observed based on analysis of growth constant data. Analysis of variance (ANOVA) of the back-calculated length data of 10 populations indicated a significant difference (p < 0.05). Out of ten populations studied, six showed significant variation of growth in 1+ age class and two showed significant variation in 2+ to 6+ age classes. Length-weight relationship of the species from all the population was calculated and the coefficient of correlation (r) was at the significant level where the value of ‘b’ was almost 3 for all the locations studied. Male C. chitala attained maturity earlier (2+ age) whereas females matured at age 3+. The percentages of mature individuals also varied between river basins. Based on this study strategies can be proposed for sustainable exploitation of the species from wild populations. 相似文献
57.
Gladys Ludevese‐Pascual Farhana Ahmed Marleen De Troch Edgar Amar Joseph Leopoldo Laranja Samuel Bode Pascal Boeckx Peter Bossier Peter De Schryver 《Journal of the World Aquaculture Society》2021,52(1):184-194
A preliminary study was conducted to demonstrate fate of the bacterial storage compound poly‐β‐hydroxybutyrate (PHB) once ingested and degraded in vivo in crustaceans. The 2% supplementation of 13C‐labeled Ralstonia eutropha DSM545 containing 75% PHB on dry weight in postlarval whiteleg shrimp, Litopenaeus vannamei resulted in consistent enrichment of two fatty acids (containing 14–24 carbons [C] in length ) pentadecanoic acid (15:0) and palmitic acid (16:0) in all lipid fractions. This could indicate that 13C signal may not only originate from the PHB but partly from the structural components of the bacterial cell. There was a trend of lower 13C enrichment in various lipid fractions of the postlarvae as compared to the diet. These findings may have important implications as to potential of PHB as energy source rather than as building block. There was a rapid transfer of 13C in the postlarvae as seen by the significant 13C enrichment in the tissues 4 hr after feeding with labeled bacterial cells. Overall, the assimilation of PHB in crustacean tissues is demonstrated for the first time. Our results indicate that PHB once ingested is rapidly assimilated in the tissues and could probably act as an energy source rather than as a building block. 相似文献
58.
Soil hydrolases and their association with carbohydrates. Active enzymes isolated from soil in the form of carbohydrate-enzyme-complexes could not be separated from each other by DEAE cellulose chromatography. All enzymes measured in this complex were recovered in Chromatographie fractions with different specific activities and variations in carbohydrate contents. There is however, no linear relationship between the quantity of carbohydrates and specific activities of the fractions. The carbohydrate-enzyme-complexes are not glycoproteins, but the enzymes are physically adsorbed on polysaccharides in a non-covalent manner. The essential role of this carbohydrate is to protect the enzyme systems against denaturation or proteolysis, thus ensuring their stability in soil. 相似文献
59.
Probal Jyoti Doley Kabita Sarma Pranab Chandra Kalita Ranjana Goswami Arup Kalita Rupan Sarkar Chethan Gollahalli Eregowda Parimal Roychoudhary Om Prakash Choudhary 《Anatomia, histologia, embryologia》2023,52(2):223-233
The present study was undertaken to characterize the ultrastructural morphology of the blood cells of commonly reared chickens in the state of Mizoram, India under backyard poultry farming. For this study, 2 ml of whole blood was aseptically collected from the wings veins of 12 chickens of three different breeds namely the Zoar, Aseel and Rhode Island Red and processed for ultrastructural imaging under standard protocols. Under scanning electron microscopy (SEM) the matured erythrocytes of Zoar, Aseel and Rhode Island Red appeared elliptical in shape while the leukocytes and thrombocytes appeared round in shape with variable surface modifications. Under transmission electron microscopy (TEM) the granules of the heterophils of Zoar, Aseel and Rhode Island Red appeared predominantly fusiform in shape, the granules of the eosinophils appeared round in shape and that of the basophils appeared pleomorphic in shape. The cytoplasm of the monocytes, medium-to-large lymphocytes and thrombocytes of Zoar, Aseel and Rhode Island Red under TEM appeared to be vacuolated and granular while that of the small lymphocytes appeared to be granular but non-vacuolated. The study concluded that the ultrastructural characteristics of the blood cells of the three breeds of chicken studied were almost similar to the blood cells of other birds reported earlier. 相似文献
60.
Zusammenfassung Fluoreszierende Pseudomonaden, die sich als Antagonistenin vitro gegenüberRhizoctonia solani undPythium aphanidermatum erwiesen haben, wurden an Gurken und Bohnen auf Antagonismusin vivo untersucht. Die Effizienz der Antagonisten in Auflaufversuchen gegenüberR. solani war niedriger als beiP. aphanidermatum. Die besten Isolate konnten in mitR. solani verseuchter Erde Auflaufraten von 30–40% erzielen, gegenüberP. aphanidermatum dagegen 40–60%. Die Wirkung der Antagonisten zur Verhütung von Spätinfektionen der Pflanzen war deutlich besser. So konnten 16 Isolate eine Schädigung durchR. solani an Bohnen zwischen 90 und 100% reduzieren. An Gurken konnten 12 Isolate eine Schädigung durchP. aphanidermatum auf 70–80% reduzieren.
Mit 4 Abbildungen 相似文献
Fluorescent pseudomonads, which showed antagonism in vitro against Rhizoctonia solani and Pythium aphanidermatum, were investigated for antagonism in vivo using bean and cucumber. The efficiency of the antagonists in germination tests against Rhizoctonia solani was lower than against Pythium aphanidermatum. In soil infected with Rhizoctonia solani the germination rates of the seeds remained between 30 and 40%, whereas against Phytium aphanidermatum some Pseudomonas-strains caused germination rates of 40–60%. The preventive effect of the antagonists against fungal infection after the germination was better. 16 isolates reduced the damage caused by Rhizoctonia solani to bean between 90 and 100%. Damage caused by Pythium aphanidermatum to cucumber was reduced by 12 antagonists between 70 and 80%.
Mit 4 Abbildungen 相似文献