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71.
B. S. Bhau K. Medhi T. Sarkar S. P. Saikia 《Genetic Resources and Crop Evolution》2009,56(8):1183-1193
Nepenthes khasiana Hook. f. belonging to monotypic family Nepenthaceae is a rare, endangered, dioecious member of the carnivorous plant found
in North-East India. The plant is endemic to the Indian state of Meghalaya and is distributed throughout the state from West
Khasi hills to East Khasi hills, Jaintia hills and East, West to South Garo hills from 1,000 to ca. 1,500 m altitude. Multi-locus
analysis using PCR based Random Amplified Polymorphic DNA (RAPD) and Inter Simple Sequence Repeats (ISSR) markers were used
for the first time to assess the genetic diversities of N. khasiana Hook. f. collected from different parts of Meghalaya. It was observed that RAPD analysis showed more polymorphism than ISSR
fingerprinting in revealing genetic polymorphism in N. khasiana Hook. f. The result of cluster analysis by using UPGMA method showed that the groups based on pooled RAPD–ISSR genetic similarity
were more similar than the groups based on RAPD. Furthermore, genetic similarity reveals variability within the population
at Jarain of Jaintia hills, while between populations the Baghmara region differs from the others with at least 40% dissimilarity.
The results show a broad range of genetic diversity within the populations of N. khasiana Hook. f. 相似文献
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74.
Upadhaya Krishna Barik Saroj Kanta Adhikari Dibyendu Baishya Ratul Lakadong Nigyal John 《林业研究》2009,20(3)
在5个典型自然种群Mylliem(种群1)、Upper Shillong(种群2)、Shillong Peak(种群3)、Laitkor(种群4)和Nongpiyur(种群5)中,详细研究了冬青树(Ilex khasiana)种群结构和再生生态学,旨在探究种群结构和再生能力的影响因素.在全光照(100%),中等光照(50%)和低光照(30%)三种光强度条件下,实验观察表明:在中等和低光照条件下的种苗成活率和生长状态好于在高光照条件下的种苗成活率和生长状态.成年树种群(≥5cm dbh)的密度直径分布揭示了一种再生种群的典型特征.对植被的破坏和人类其他干扰导致森林树冠疏开使光照增强,造成自然种群(L khasiana)幼苗的高死亡率.本研究结果对制定适当的物种保护措施有重要价值. 相似文献
75.
Several Ayurvedic plants are known to have activity against diverse urinary crystals. The traditional knowledge of Ayurveda, collective clinical experience in arthritis and the earlier experimental studies on urinary crystals led to the selection of three plants, viz. Rotula aquatica, Commiphora wightii Bhandari syn. C.mukul. and Boerhaavia diffusa for screening anticrystal activity against basic calcium phosphate (BCP), calcium pyrophosphate (CPPD) and monosodium urate monohydrate (MSUM). The effects of each plant were assayed on microcrystals in 24-well microplates in vitro. Our results show that the aqueous extracts of only R. aquatica and C. wightii have shown crystal dissolving activity against MSUM. 相似文献
76.
Trisha Roy Samar Chandra Datta Abhijit Sarkar Siddhartha Sankar Biswas 《Archives of Agronomy and Soil Science》2018,64(11):1564-1581
Non-renewable nature of rock phosphate (RP) reserves coupled with open ended nature of P cycle makes it imperative for maximum utilization of available P resources. In this context, use of Indian RPs from Purulia and Udaipur along with citric acid loaded nanoclay polymer composite (CA-NCPC) as P source to costly diammonium phosphate (DAP) was investigated through an incubation experiment followed by a greenhouse experiment with wheat-rice cropping sequence in a Luvisol (pH 5.14, available P 13.5 mg kg?1). Soil available P, crop yield parameters and dynamics of soil P fractions were taken to judge the efficacy of CA-NCPC in solubilizing RPs. Application of CA-NCPC and DAP resulted in 82% and 69% increase in available P over control, respectively under incubation study. Direct effect of treatment receiving CA-NCPC + RP on yield and P uptake by wheat was comparable with DAP but residual impact of CA-NCPC + RP (16.7 g pot?1) was better than DAP (13.8 g pot?1) in rice. The changes in inorganic P fractions were also significant as inclusion of RP increased calcium-P from 16.1 to 61.5 mg kg?1. Results indicated potentiality of RPs treated with CA-NCPC as an alternate P source which could prove promising amidst P scarcity. 相似文献
77.
A study on evapotranspiration from potato fields was conducted in the Lower Gangetic Plains of India. The input data required for the CROPWAT irrigation management model was collected, and evapotranspiration (ET) and irrigation water requirement (IWR) for potato crops were calculated using the model. Firstly, the CROPWAT model was validated by comparing simulated crop evapotranspiration (SET) with actual ET calculated through the field water balance method. Thereafter, SET and IWR for nine locations in the lower Gangetic plains of India were calculated for the period from 1996–1997 to 2008–2009, for the current situation (using 20-year-average weather data of the stations), and for elevated thermal conditions, i.e. considering 2 and 3 °C increases over the current temperature. The future change in IWR for potato up to 2050 was also calculated considering the projected climatic scenario generated by the PRECIS model. The CROPWAT calculated IWR values showed an increasing, though not statistically significant, trend in requirement of irrigation water for potato across the nine locations during the period from 1996–1997 to 2008–2009. At a temperature increase of 2 °C over normal, the mean SET of potato would increase by 0.06 mm per day and the average IWR would be 6.0 mm per season more. If the mean temperature would be 3 °C more than normal, the SET would be 0.16 mm day?1 higher and the IWR 16.6 mm. Also based on the projected climatic scenario generated by the PRECIS model, the future SET up to 2050 showed an increasing trend. The present study indicates increasing demand for irrigation water, which may significantly affect the agricultural scenario in the region. 相似文献
78.
The present study determined the effective concentrations of clove oil and MS‐222 in juvenile rohu Labeo rohita for quick induction and recovery. The immune‐biochemical responses due to 0, 1 and 24 hr exposure to those anaesthetics were also evaluated. Of four concentrations of the anaesthetics examined, the lowest effective concentration of clove oil and MS‐222 were 50 µl/L and 125 mg/L respectively. Clove oil and MS‐222 significantly increased the myeloperoxidase, total protein and alkaline phosphatase activity at some of the holding durations. However, superoxide anion production (after 0 and 1 hr) and antiprotease activity (after 24 hr) were significantly reduced in fish exposed to clove oil. Serum glucose content was significantly elevated in the MS‐222‐treated group. Furthermore, the clove oil‐treated group showed significantly higher levels of serum Na+ and K+, while the aspartate and alanine aminotransferase activities were significantly enhanced in the MS‐222 group. The use of both clove oil and MS‐222 is advised as an anaesthetic agent for rohu with a bias towards clove oil, considering its economic and operational feasibility. 相似文献
79.
Soils are the third biggest sink of carbon on the earth. Hence, suitable land uses for a climatic condition are expected to sequester optimum atmospheric carbon in soils. But, information on how climatic conditions and land uses influence carbon accumulation in the soils on the Himalayan Mountains is not known. This study reports the impact of four climatic conditions (sub-tropical, altitude: 500–1200 m; temperate 1200–2000 m; lower alpine 2000–3000 m; upper alpine, 3000–3500 m) and four land uses (forest, grassland, horticulture, agriculture) on the concentrations and stocks of soil organic carbon (SOC) in upper (0–30 cm) and deeper (30–100 cm) soil depths on the western Himalayan Mountains of India. The study also explored the drivers which influenced the SOC stock build up on the mountains. Rainfall and soil moisture showed quadratic relations, whereas temperature declined linearly with the altitude. SOC stock as well as concentration was the highest (101.8 Mg ha− 1 in 0–30 cm, 227.97 Mg ha− 1 in 0–100 cm) in temperate and the lowest in sub-tropical climate (37 Mg ha− 1 in 0–30 cm, 107.04 Mg ha− 1 in 0–100 cm). Pattern of SOC stock build up across the altitude was: temperate > lower alpine > upper alpine > sub-tropical. SOC stocks in all land uses across the climatic conditions, except agriculture in lower alpine, was higher (0.7 to 41.6%) in the deeper than upper soil depth. SOC stocks in both the depths showed quadratic relations with soil temperature and soil moisture. Other factors like fine soil particles, land-use factor and altitude influenced positively whereas slope and pH, negatively to the SOC stocks. In all climatic conditions, other than temperate, SOC stocks were greater in natural ecosystems like forests and pastures (112.5 to 247.5 Mg ha− 1) than agriculture (63 to 120.4 Mg ha− 1). In temperate climate, SOC stock in agriculture (253.6 Mg ha− 1) on well formed terraces was a little higher than forest (231.3 Mg ha− 1) on natural slope. These observations, suggest that land uses on temperate climate may be treated as potential sinks for sequestration of the atmospheric carbon. However, agriculture in subtropical climate need to be pursued with due SOC protection measures like the temperate climate for greater sequestration of the atmospheric carbon. 相似文献
80.