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41.
A survey was conducted in 17 selectedthaluks (revenue sub-divisions) of Kerala state to elucidate the floristic structure, composition and the extent of similarities and diversities in the composition of homegardens of Kerala, with particular reference to small (below 0.4 ha), medium (0.5 to 2 ha) and large (>2.0 ha) holding size categories. Besides attempts wer also made to characterize the potential of homegardens to supply commercial timber and fuelwood. Two hundred and fifty two farmers were selected through a stratified random process. In addition to gathering general information on crop and livestock production enterprises, all scattered trees and shrubs (15 cm girth at breast height) on the homestead and border trees except palms and rubber were enumerated.There was tremendous variability both in the number of trees and shrubs present and species diversity of the selected homesteads in different provinces. The small, medium and large sized holdings also exhibited profound variability in the number of woody taxa and individuals present. In total, 127 woody species (Girth at Breast Height (GBH) 15 cm) were encountered. The mean number of woody taxa found in the homegardens ranged from 11 for Pathanapuram to 39 in Perinthalmanna. Floristic diversity was higher in the smaller homesteads. It decreased with increasing the size of holdings. Mean Simpson's diversity index for the homesteads ranged from 0.251 (Kochi) to 0.739 (Kottarakkara) suggesting that floristic diversity of homegardens was moderate to low compared to a value over 0.90 for the species-rich evergreen forests of the Western Ghats. The Sorensen's similarity indexes suggested a moderately high degree of similarity for the different tree species encountered in the homesteads of Kerala.No clear cut planting pattern was discernible in the homegardens of Kerala. The homegarden trees and shrubs were either scattered throughout the homestead or on farm boundaries. Farmers tend to prefer timber trees such as ailanthus (highest frequency) and teak besides fruit trees such as mango, jack, cashew and the like. Major homegarden species were represented in all diameter classes. The diameter structure, however, exhibited a slightly skewed (+) distribution pattern, having the highest frequency in the 20–30 cm classes ensuring adequate regeneration status and in that process making homegardens a sustainable as well as dynamic land use system.Standing stock of timber and firewood in the homestead of differentthaluks are presented. Average commercial standing stock of homesteads ranged from 6.6 to 50.8 m3 ha–1 and fuel wood volume was of the order of 23 to 86 m3 ha–1. Implicit in the high commercial timber volume and fuel wood volume is that a substantial proportion of the society's wood demands are met from the homesteads. Palms, however, constituted the dominant component of standing commercial timber and fuel wood volumes accounting as much as 63% and 72%, respectively, of the total wood in these categories. 相似文献
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Myocardial infarction is the number one killer disease in many parts of the world. The cardioprotective effect of Marutham, a polyherbal formulation on serum and heart tissue lipids, serum lipoproteins and heart membrane bound enzymes in isoproterenol induced myocardial infarction was studied in Wistar rats. Pretreatment with Marutham at different doses of 30, 60 and 90 mg kg(-1) to isoproterenol treated rats significantly prevented the altered lipid profile and membrane bound enzymes to near normal status. The results of our study showed the cardioprotective potential of Marutham on isoproterenol induced myocardial infarction in rats. 相似文献
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Changes in residue management and incorporation of organic manures may help in carbon sequestration, restoring soil organic carbon (SOC) and sustaining the productivity of land under a cropping system. An experiment of multi-ratooning sugarcane (Saccharum officinarum L.) was initiated in 2003 in Inceptisols of Indian subtropics, to assess the effect of different organic manures and chemical fertilizer, on the crop productivity and soil quality. The annual sugarcane shoot biomass production in organic manure treatments was at par with the chemically fertilized treatment. Gross input of carbon (GIC) by the sugarcane crop was estimated to be 11.7–12.4 t ha−1 y−1 in different organic manure treatments compared to 8.4 and 5.0 t ha−1 y−1 in NPK and control treatments, respectively. The respiratory loss of C (RLC) increased linearly with increasing input of C in soil and it ranged from 3.3 to 4.1 t ha−1 y−1 in different treatments with maximum in FYM and minimum in control treatment. The sugarcane biomass added in the soil humified at a rate constant of 0.38 in sub-tropical conditions and an addition of 3.9 t C ha−1 y−1 is required to maintain SOC in equilibrium. After 5 years of sugarcane cropping (one plant + four ratoons) an increase of 2.3–17.1 t ha−1 in SOC over initial content was recorded with different treatments. Results in coming years from this long-term experiment shall add to the present calculated relationships between carbon addition and storage in sugarcane multi-ratooning crop production system under sub-tropical condition of India. 相似文献
46.
Ajay S. Khandagale Suchetha N. Kumari Siva Durga Suman Joshi Krishnaprasad Nooralabettu 《Journal Of Aquatic Food Product Technology》2013,22(4):354-367
Trypsin from viscera of Indian mackerel (Rastralliger kanagurta) was purified by ammonium sulphate precipitation and chromatographic techniques such as size exclusion, ion exchange, and affinity chromatography, with a 14.4-fold increase in specific activity and 18.7% recovery. The molecular weight of the trypsin was estimated to be approximately 26 kDa using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Purified trypsin showed amidase-specific activity which was determined using benzoyl-dl-arginine-p-nitroanilide (BAPNA). The optimum pH and temperature for isolated trypsin activity were 9.0 and 50°C, respectively. The purified trypsin was strongly inhibited by soybean trypsin inhibitor (SBTI) and N-p-tosyl-1-lysine chloromethyl ketone (TLCK). Purified trypsin showed almost 40% recovery at high NaCl concentration (30%). The N-terminal amino acid sequence of the first 10 amino acids of purified trypsin was IVGGYESQPH. The Michaelis-Menten constant (Km) and catalytic constant (Kcat) of purified trypsin were 0.430 mM and 0.77 s?1, respectively, determined using BAPNA as a substrate. Purified trypsin showed digestion of casein similar to bovine trypsin by the fluorometric method. 相似文献
47.
Extracts of Lantana camara var. aculeata leaves were studied for their phytochemical constituents and termiticidal effects against adult termite workers. The 5% chloroform extract was found to be significantly effective against termite workers. 相似文献
48.
Random amplified polymorphic DNA markers were used to study sub-structure and genetic differentiation amongst 31 populations
(seven cultivated and 24 wild populations) belonging to 14 Asiatic Vigna species. Ten pre-selected RAPD primers generated 152 polymorphic amplification products. Estimates of polymorphism indices
were higher for the wild taxa in comparison to the cultivated forms. FST values between populations ranged from 0.111 to 0.801 and Nei’s genetic diversity values between and within species varied
from 0.26 to 0.70 and 0.04 to 0.56 respectively. The high FST and FCT values indicated strong subdivision of populations and high differentiation among species. Analysis of molecular variance
was performed by grouping the populations conforming to specific species. AMOVA was also performed separately to better resolve
the differentiation of species within mungo–radiata complex. Molecular phylogenetic relationships amongst the species of radiata–mungo complex; namely, black gram (V. mungo (L.) Hepper), green gram (V. radiata (L.) Wilczek), V. radiata var. sublobata, V. radiata var. setulosa, V. mungo var. silvestris and V. hainiana, were studied through cluster analyses. Two distinct groups were recognized within the complex, with population samples of
V. hainiana forming one cluster. Further, V. hainiana appeared to be equidistant to both V. radiata and V. mungo. 相似文献
49.
Das Anjan Yadav Ramesh Kumar Choudhary Harshwardhan Lata Suman Singh Saurabh Kumar Chavlesh Kumari Shilpi Boopalakrishnan G. Bhardwaj Rakesh Talukdar Akshay 《Genetic Resources and Crop Evolution》2022,69(2):771-791
Genetic Resources and Crop Evolution - Okra [Abelmoschus esculentus (L.) Monech.] is an annual herb of the family Malvaceae and has tremendous nutritional and industrial potential. However, the... 相似文献
50.
本研究以p BI121为植物表达载体,在已构建的无融合生殖基因表达载体p BI121-Mh SERK1和p BI121-Mhd SERK1的基础上,利用根癌农杆菌介导法,将苹果属无融合生殖相关基因SERK1转入受体植株烟草中。研究结果表明:烟草叶片浸染后,经共培养和选择培养形成再生芽,分别获得7株p BI121-Mh SERK1和6株p BI121-Mhd SERK1转烟草抗性植株,PCR检测证明已成功获得Mh SERK1和Mhd SERK1烟草转化株系。本研究可为下一步无融合生殖相关基因功能验证研究奠定基础。 相似文献