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121.
Sachin Srivastava A. K. Chopra Piyusha Sharma Vinod Kumar 《Communications in Soil Science and Plant Analysis》2017,48(5):511-523
A field experiment was conducted to study the biohydrological properties of soil and yield of Vigna unguiculata L. Walp irrigated with five concentrations of sugar mill wastewater (SMW) during the Kharif and Zaid seasons. Among various concentrations of SMW, irrigation with 100% SMW significantly (P < 0.001) increased zinc (Zn), copper (Cu), cadmium (C), nickel (Ni), chromium (Cr), and iron (Fe) of the soil, while decreased total bacteria, fungi, actinomycetes, yeast, and rhizobia of the soil in both the cultivated seasons. However, the values of these metals were below the recommended permissible limit except Cd. Enrichment factor (Ef) of various heavy metals for soil was in the order Ni > Cr > Cd > Zn > Cu after irrigation with SMW. The crop yield of V. unguiculata was found to be inversely proportional to concentrations of SMW, with the best results being obtained at 50% SMW concentrations after 90 days of irrigation in both the cultivated seasons. 相似文献
122.
Prem?Pokharel Jin-Hyeob?Kwak Scott?X.?ChangEmail author 《Biology and Fertility of Soils》2017,53(6):701-713
We evaluated the impact of exponential fertilization in nursery and weed removal in the field on growth and nitrogen (N) retranslocation and uptake from the soil of jack pine (Pinus banksiana Lamb.) seedlings planted on an oil sands reclaimed soil. Exponential fertilization is a method of supplying nutrients at an exponential rate to achieve constant internal nutrient concentrations in seedlings without changing their size during their growth in the nursery. The N retranslocation in seedlings was traced using 15N isotope labeling. Exponential fertilization increased nutrient reserve in the seedling in nursery production, and increased height (P = 0.003), root collar diameter (P < 0.001), total biomass (P < 0.001), and N content (P < 0.001) of seedlings at the end of first growing season in the field growth. Conventionally fertilized seedlings allocated a greater percent of biomass to roots than to current-year needles. The 15N isotope analysis showed that 59 to 82% of total N demand of new growth was met by retranslocation from old tissues. Exponential fertilization increased N retranslocation by 147% (P < 0.001) and N uptake from the soil by 175% (P = 0.012). Weed removal marginally increased (P = 0.077) N uptake from the soil but decreased (P = 0.046) N retranslocation with no net effect on total N content in new tissues. We conclude that exponential fertilization improves the early growth of jack pine and can help improve revegetation in reclaiming disturbed oil sands sites. 相似文献
123.
Gowane G. R. Akram Najif Prince L. L. L. Prakash Ved Kumar Arun 《Tropical animal health and production》2017,49(4):867-873
Tropical Animal Health and Production - Enterotoxaemia (ET) is a fatal enteric disease of small ruminants attributable to a toxigenic type of Clostridium perfringens. The key strategy for... 相似文献
124.
Krishna Mohan Vijay Kumar Mihir Sarkar B. S. Prakash 《Tropical animal health and production》2010,42(1):21-26
The objective of this study were (1) to establish the duration of behavioral estrus signs and timing of ovulation in Murrah
buffaloes (n = 10) and (2) to determine relationship between behavioral estrus signs with change in plasma estrogen concentrations.
Estrus and its behavioral signs were detected at hourly intervals by visual observations, per recta examination of genitalia
and bull parading four times in a day for 30 minutes each. Among the behavioral signs of estrus, swollen vulva (80%) was the
best indicator of estrus followed by excitement (70%). Among the duration of behavioral estrus signs the first and longest
duration of estrus signs was swollen vulva which was seen upto 19.8 ± 0.8 h after onset of estrus. The mean total duration
of estrus symptoms from appearance to disappearance of all the behavioral estrus symptoms was 23.5 ± 1.7 h. All the behavioral
estrus symptoms were observed during the period of estrogen surge. Endocrine profile during the periestrus period showed that
the mean peak concentrations of total estrogen 23.9 ± 3.9 pg/ml occurred at 8.8 ± 1.7 h after onset of estrus. The average
number of estrus symptoms observed per animal during onset of spontaneous estrus was 5.7. Ovulation occurred after 37.4 ± 1.7 h
after onset of estrus and 13.4 ± 1.0 h after end of total estrogen surge respectively. In conclusion, our results suggest
that all signs of behavioral estrus occurred during the preovulatory rise in estrogens. The first sign of estrus to be observed
was a swollen vulva and this symptom persisted the longest. 相似文献
125.
Hari Prasad Aithal MVSc PhD Prakash Kinjavdekar MVSc PhD Abhijit Motiram Pawde MVSc PhD Gaj Raj Singh MVSc PhD Harish Chandra Setia MSc 《Veterinary surgery : VS》2010,39(5):621-626
Objectives: To report the repair of tibial diaphyseal fractures in 2 calves using a circular external skeletal fixator (CEF). Study Design: Clinical report. Animals: Crossbred calves (n=2; age: 6 months; weight: 55 and 60 kg). Methods: Mid‐diaphyseal tibial fractures were repaired by the use of a 4‐ring CEF (made of aluminum rings with 2 mm K‐wires) alone in 1 calf and in combination with hemicerclage wiring in 1 calf. Results: Both calves had good weight bearing with moderate lameness postoperatively. Fracture healing occurred by day 60 in 1 calf and by day 30 in calf 2. The CEF was well maintained and tolerated by both calves through fracture healing. Joint mobility and limb usage improved gradually after CEF removal. Conclusions: CEF provided a stable fixation of tibial fractures and healing within 60 days and functional recovery within 90 days. Clinical Relevance: CEF can be safely and successfully used for the management of selected tibial fractures in calves. 相似文献
126.
Sudershan Kumar Anil K. Srivastava V. K. Dumka Naresh Kumar Rajinder K. Raina 《Veterinary research communications》2010,34(6):503-510
Pharmacokinetics and milk levels of ceftriaxone were studied in healthy and endometritic cows following single intravenous
administration. The drug was detected up to 8 h of dosing in plasma of healthy and endometritic cows and the drug disposition
followed three-compartment open model. The values of Vdarea, AUC, t1/2β, ClB, MRT and P/C ratio were 0.50 ± 0.19 L.kg−1, 62.2 ± 23.3 μg.ml−1.h, 1.02 ± 0.07 h, 0.30 ± 0.09 L.kg−1.h−1, 1.55 ± 0.25 h and 0.52 ± 0.27, respectively, in healthy and 1.55 ± 0.52 L.kg−1, 37.0 ± 17.1 μg.ml−1.h, 1.56 ± 0.25 h, 0.56 ± 0.14 L.kg−1.h−1, 2.14 ± 0.34 h and 1.44 ± 0.60, respectively, in endometritic cows. The drug was detected in milk for 36 h after administration.
For MIC90 of 0.5 μg.ml−1 the most appropriate dosage for ceftriaxone, would be 9.0 mg.kg−1 repeated at 6 h intervals for the treatment of endometritis in cows. 相似文献
127.
Phenolic glycosides from Dodecadenia grandiflora and their glucose-6-phosphatase inhibitory activity
Manmeet Kumar Preeti Rawat Mohammad Faheem Khan Akhilesh K. Tamarkar Arvind K. Srivastava Kamal R. Arya Rakesh Maurya 《Fitoterapia》2010
Phytochemical investigation of Dodecadenia grandiflora leaves led to the isolation and identification of three phenolic glycosides, designated 1-[(4′-O-(E)-p-coumaroyl)-β-d-glucopyranosyl]-oxy-2-phenol (1), 1-[(6′-O-(E)-p-coumaroyl)-β-d-glucopyranosyl]-oxy-2-phenol (2) and 1-[O-β-d-glucopyranosyl(1→2)-β-d-glucopyranosyl]-oxy-2-phenol (3), along with nine known compounds. Compounds 1, 2, 5 and 9 exhibited significant glucose-6-phosphatase inhibitory activity (63.7, 66.9, 82.9 and 85.4%) with IC50 values of 88.5, 81.0, 51 and 50 μM respectively. On the basis of biological results, a structure–activity relationship has been discussed. 相似文献
128.
129.
H.C. Srivastava P. Narasimhan 《The Journal of Horticultural Science and Biotechnology》2013,88(1):97-104
In a study of three seed-bearing varieties of guava and one seedless variety changes in size and specific gravity and in the content of water, titratable acid, reducing and non-reducing sugars, tannins, pectin, and ascorbic acid were recorded at intervals from fruit-set to harvest. Respiration rates were also determined during this period.Patterns of change were generally similar in seeded and unseeded varieties, though the sugars and ascorbic acid contents rose earlier and to higher levels in the seedless than in the seeded, and the fruits matured and fell from the trees earlier.Increasing ascorbic acid content, concurrent with declining pectin content in the seeded varieties, is consistent with the hypothesis that pectin degradation and ascorbic acid are linked, but in the seedless variety a rapid rise in the ascorbic acid content occurred during a period of pectin accumulation. The end of the initial rapid decline in respiration rate generally coincided with the beginning of reducing-sugar accumulation. 相似文献
130.
Prakash Lakshmanan Majid Danesh Acram Taji 《The Journal of Horticultural Science and Biotechnology》2013,88(2):158-163
SummaryEfficient in vitro procedures for mass propagation of four commercially important Echinacea species have been deveoped. Plants of E. angustifolia, E. pallida, E. paradoxa and E. purpurea were regenerated by three methods, namely axillary bud proliferation, adventitious shoot formation and somatic embyrogenesis. Shoot tips obtained from in vitro germinated seedlings, adventitious shoots or somatic embryo-derived plantlets, when cultured on Murashige and Skoog medium enriched with 1 μM 6-benzylaminopurine, 2 μM kinetin, 0.5 μM indole-3-butyric acid and 4 mg–1 paclobutrazol multiplied three-fold within 3–4 weeks in culture. Incorporation of paclobutrazol in the shoot multiplication medium was necessary to recover healthy and robust shoots suitable for rooting. Direct, high-frequency shoot formation on intact leaves of shoots grown on 6-benzylaminopurine and kinetin-supplemented media, an unusual and novel observation made in this study, occurred in all the species studied. Rooting of in vitro developed shoots was achieved relatively easily with Murashige and Skoog basal medium rather than with auxin-enriched media. Culturing of hypocotyl explants on medium containing 3,6-dichloro-o-anisic acid (commonly known as dicamba), or 2,4-dichlorophenoxyacetic acid, resulted in direct somatic embryogenesis in all the species examined. The presence of cytokinin was required for somatic embryo germination, but further development of germinated somatic embryos into normal plantlets occurred in Murashige and Skoog medium. We conclude that the procedures described here could be used for rapid propagation as well as genetic transformation of commerically cultivated Echinacea species. 相似文献