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61.
Survival,male morphotypes,female and male proportion,female reproductive status and tag loss in crosses among three populations of freshwater prawn Macrobrachium rosenbergii (de Man) in India
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Bindu R Pillai Kanta D Mahapatra Raul W Ponzoni Lopamudra Sahoo P L Lalrinsanga Wagdy Mekkawy Hooi Ling Khaw Nguyen H Nguyen Swagathika Mohanty Sovan Sahu Gunamaya Patra 《Aquaculture Research》2015,46(11):2644-2655
The present study examined the variation in survival, proportion of male morphotypes, female and male proportion, female reproductive status and tag losses in nine crosses from a complete (3 × 3) diallel mating of three populations of Macrobrachium rosenbergii in India. The populations originated from Gujarat (north‐west), Kerala (south‐west) and Odisha (east), representing different agro‐ecological regions in India. Progeny from 60 families (4773 juveniles) were individually tagged and reared for 16–17 weeks in earthen ponds. Binary logistic regression was used to analyse the data. Survival rate was greatest (0.88) for Kerala × Odisha (KO; the first letter represents the sire), whereas it was lowest (0.75) for both Kerala × Kerala (KK) and Gujarat × Kerala (GK). Significantly greater proportions of large male morphotypes were observed in KK cross and in combinations involving Kerala population. The highest proportion of immature females, as well as of non‐berried females, was observed in the Odisha × Odisha (OO) cross. Tag loss was greatest for KK (0.35) and lowest for GG (0.19). We found significant variations among crosses for all studied traits suggesting the possibility of including them in genetic improvement programmes of this species. 相似文献
62.
S. Sarao Preetinder K. Sahi Gurpreet Neelam Kumari S. Mangat Gurjit C. Patra Bhaskar Singh Kuldeep 《水稻科学》2016,23(4):219
Out of 1 989 wild accessions sown in seed boxes for screening, only 1 003 wild accessions with good germination were screened against brown planthopper (BPH), Nilaparvata lugens (Stål) under greenhouse conditions. The collection comprised of accessions from 11 wild species and African cultivated rice. The germplasm was screened for BPH following standard seed box screening technique in the greenhouse. As many as 159 accessions were identified as resistant during the year 2012 based on one year screening. A selected set of BPH resistant accessions were screened again during 2013. Based on the two years screening, seven accessions of O. nivara (AA), one accession of O. officinalis (CC), seven accessions of O. australiensis (EE), five accessions of O. punctata (BB and BBCC) and nine accessions of O. latifolia (CCDD) were confirmed to be resistant to BPH. So far no BPH resistance genes have been identified and designated from O. nivara and O. punctata, hence these may act as new sources of resistance. 相似文献
63.
Use of urea coated with natural products to inhibit urea hydrolysis and nitrification in soil 总被引:2,自引:0,他引:2
Dharani D. Patra Usha Kiran Sukhmal Chand Mohd. Anwar 《Biology and Fertility of Soils》2009,45(6):617-621
Laboratory incubation experiments were conducted with uncoated urea or urea coated with dementholized oil (DMO), pitch (the
mint oil discard), terpenes (the products of menthol mint oil), or dicyandiamide (DCD) to study the retardation of urea hydrolysis
and nitrification in soil. Two levels (0.5 and 1 %) of coating were tested. Urea was applied at a rate of 200 mg kg−1 of dry weight of soil. The urea hydrolysis and nitrification processes were inhibited by all three natural products. All
the three natural products viz., DMO, terpenes, and pitch significantly retarded urease activity of soil. 相似文献
64.
Tapas Kumarpandit Sushanta Kumarnaik Prasenjit Kumar Patra Nilanjan Dey Dilip Kumar Das 《Communications in Soil Science and Plant Analysis》2017,48(4):357-369
Spinach grown in cadmium (Cd)-contaminated soils accumulates Cd compounds in toxic concentration contaminating the food chain leading to the chronic toxic effects on human and animal health. A study was conducted in a Cd-contaminated soil to examine the ameliorative effect of lime and organic manure on the mobility of Cd and its uptake in spinach. Application of lime or organic manure or both decreased the Cd concentration in soil and shoots and increased chlorophyll content of leaves. As compared to the control treatment, combined application of lime and organic manure decreased the level of Cd in soil by 54.7%, in spinach shoot by 61.3%, and the transfer factor of Cd by 35.0% and increased in leaf chlorophyll content by 29.4%. Combined application of lime and organic manure emerged as a viable option in reducing the mobility of Cd in contaminated soil for growing spinach. 相似文献
65.
Awasthi Mukesh Kumar Wang Quan Chen Hongyu Liu Tao Awasthi Sanjeev Kumar Duan Yumin Varjani Sunita Pandey Ashok Zhang Zengqiang 《Journal of Soils and Sediments》2019,19(12):3883-3897
Journal of Soils and Sediments - This study aims to assess the effect of amendment of an alkaline Zn, Cd-contaminated soil with compost of wheat straw biochar (CB) (4, 8, 12, and 18%) and sludge... 相似文献
66.
Eight 6–9 month old calves, showing clinical signs of intermittent haemoglobinuria, even after treatment with an antipiroplasmal drug (4,4-diamidinodiazoaminobenzene diaceturate), were examined for oxidative damage to their erythrocytes and the presence of hemoprotozoa in blood smears. Four calves without signs of haemoglobinuria served as controls. The blood smears from three of the eight calves contained piroplasms for Theileria annulata. Irrespective of the presence of piroplasms in their blood smears, the calves with haemoglobinuria had significantly (p<0.01) lower haemoglobin concentrations (Hb) and packed cell volumes (PCV). The lipid peroxide level in the erythrocytes, but not in the plasma, of calves with red urine was significantly (p<0.05) higher than that for the controls. It is concluded that haemoglobinuria, irrespective of the presence of piroplasms in blood smears, is associated with oxidative stress to erythrocytes and peroxidation of polyunsaturated fatty acids of cell membrane. 相似文献
67.
Antibacterial activity of luteoforol from Bridelia crenulata 总被引:1,自引:0,他引:1
Ramesh N Viswanathan MB Saraswathy A Brindha P Balakrishna K Lakshmanaperumalsamy P Patra A 《Fitoterapia》2001,72(4):409-411
The methanol extract of Bridelia crenulata stem bark (50-1.5625 mg/ml) and its isolated luteoforol (2-0.25 mg/ml) showed concentration-dependent inhibiting activity against all 10 tested bacteria. 相似文献
68.
Transgenic Bt-Cotton Affects Enzyme Activity and Nutrient Availability in a Sub-Tropical Inceptisol 总被引:1,自引:0,他引:1
B. Sarkar A. K. Patra & T. J. Purakayastha 《Journal of Agronomy and Crop Science》2008,194(4):289-296
We investigated the dynamics of N and P availability in the rhizosphere of Bt and non- Bt cotton crops during their growth. In a net-house pot culture experiment at the Indian Agricultural Research Institute, New Delhi, Bt -cotton (cv. MRC-6301 Bt ) and its non-transgenic near-isoline (MRC-6301) were grown on a sandy loam soil until maturity. A control (no-crop) treatment was also included. Rhizosphere soil and root samples were collected at 60, 90, and 120 days after sowing (DAS). Soil samples were analysed for dehydrogenase activity, soil respiration, mineral-N and Olsen-P. Results have revealed a significant reduction in dehydrogenase activity (−17 %) and soil respiration (−3.5 %) in the rhizosphere of Bt -cotton over non- Bt isoline. Total mineral-N (NH4 + -N + -N) in soil was reduced by 14 %, whereas Olsen-P was increased by 8 % because of Bt -cotton. Root biomass yields were not different (P > 0.05), but root volume was significantly higher in Bt than non- Bt isoline. Time of sampling strongly (P < 0.05) affected the above parameters, showing their highest values at 60 or 90 DAS. A significant interactive effect of sampling time and treatments was also indicated. Our results suggest that Bt -cotton may constrain the availability of N, but enhances P-availability in these soils. 相似文献
69.
A study was conducted to determine mineralization rates in the field and in different soil layers under three grassland managements
(viz. a reseeded sward, a permanent sward with a conventional N management, and a long-term grass sward with 0 N (0-N) input).
Potential mineralization rates of soil particles (sand, silt and clay) and macro-organic matter fractions of different sizes
(i.e. 0.2–0.5, 0.5–2.0 and >2 mm) were also determined in the laboratory. In the reseeded plots, net mineralization was unchanged
down to 40 cm depth. In the undisturbed conventional-N swards, mineralization rates were substantially higher in the top layer
(0–10 cm) than in the deeper layers. In plots which had received no fertilizer N, mineralization was consistently low in all
the layers. There was more macro-organic matter (MOM) in the 0-N plots (equivalent to 23 g kg–1 soil for 0–40 cm) than in the two fertilized plots (i.e. conventional-N and reseeded) which contained similar amounts (ca. 15 g kg–1 soil). C and N contents of separated soil particles did not differ amongst the treatments, but there were large differences
with depth. Potential mineralization in the bulk soil was greatest in the 0–10 cm layers and gradually decreased with depth
in all the treatments. Separated sand particles had negligible rates of potential mineralization and the clay component had
the highest rates in the subsurface layers (10–40 cm). MOMs had high potential rate of mineralization in the surface layer
and decreased with soil depth, but there was no clear pattern in the differences between different size fractions.
Received: 17 November 1997 相似文献
70.
Precedence of microbial colorants can be seen in almost all the industrial sectors viz. food, textile, paper, agriculture, pharmaceutical, and cosmetics. These colorants are gaining popularity due to their salient advantages over synthetic and natural dyes. This study deals with the optimization and extraction of such colorants from Penicillium minioluteum for the purpose of dyeing different protein fibers. Penicillium minioluteum was cultured under different growth conditions to optimize the extracellular color production. The extracellular colorant grown under optimized fermentation conditions (medium-sabouraud; pH-5.6; temperature-15 °C; time-20 days; incubation-static) in 3000 ml haffkine flask showed maximum color or highest optical density of 1.014 at λ max=490 nm. Later on, this colorant was extracted using nbutanol. The remaining mycelial mat obtained after filtration was extracted using different chemical and mechanical procedures to get the intracellular colorant. Highest O.D of 0.897 was recorded at λ max=490 nm when desiccated powdered mycelial mat was extracted with methanol. Dyed silk and leather with the extracellular colorant showed color strength (K/S) as 3.88 and 3.81, respectively, whereas silk and leather dyed with the intracellular colorant showed K/S as 0.56 and 0.55, respectively. The color strength of extracellular dyed samples was found to be three times higher as compared to the samples dyed with the intracellular aqueous colorant of the same optical density. After dyeing, two different shades were obtained viz. deep red with the extracellular colorant and beige with the intracellular colorant on mulberry silk and wet blue goat nappa skin leather. Fastness towards rubbing was found to be good for both the samples. Wash fastness was excellent on silk. Fastness towards light was poor for both silk and leather. Furthermore, the color yield of the extracellular colorant (0.62 %) was found to be approximately five times more than the color yield of the intracellular colorant (0.14 %). 相似文献