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1.
Betelvine (Piper betle) is an important cash crop in India. The cultivation of this crop is seriously threatened by several pest insects, for example the homopterans Aleurocanthus rugosa, Dialeuroides pallida, Aphis gossypii and Tricentrus gibbosulus and the thysanopterans Membrothrips indicus, Zaniothrips ricini, Mymarothrips garuda and Aroidothrips longistylus and by the plant pathogenic fungi Curvularia lunata, Phytophthora parasitica, Colletotrichum piperis and Fusarium moniliforme. The pest and pathogen species are attacked by natural enemies belonging to the Coleoptera, Diptera, Heteroptera, Hymenoptera, Aranea and Acari. While occurrence of non-acarine enemies is confined to certain seasons, the acarine enemies are associated with the insect pests and fungal pathogens throughout the year. The predatory mites Walzia indiana and Proctolaelaps pygmaeus and the mycophagous mites Unguizetes clavatus and Acarus sp. seem to have potential to control the insect pests and fungal pathogens, respectively.  相似文献   

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3.
A new genus Siberioklipsteinia (with the type species S. dagysi sp. nov.) and a new species Arctoarpadites nelgesensis are described from the Carnian of the Kharaulakh Range and Yana Upland (eastern Yakutia). The new data allow refinement of the taxonomy of Carnian ammonoids of northeastern Asia and emendation of some details of their geographical differentiation. The new ammonoid taxa belong to the family Arpaditidae, which was not previously recorded from the eastern Boreal Realm.  相似文献   

4.
Plant wealth and diversity of four sacred groves – twoanthropogenic stands and two natural forest patches – along the southeastcoast of India adjoining Pondicherry was studied. A total of 111species, belonging to 103 genera in 53 families, were recorded from thefour sites, which together measure 15.6 ha. The number of woody species (girth at breast height(gbh) 20 cm) was 20 each in Keezbuvanagiri (KBG) andKilialamman (KLM) grove, followed by 13 in Periyakattupalayam (PKP) and 15in Periyamudaliar chavadi (PMC). Based on the important value index (IVI), PMCgrove is an association of Aglaia elaeagnoidea,Borassus flabellifer and Pterospermumsuberifolium. A two-layered forest structure resembling tropical dryevergreen forest (TDEF) was found there. Stratification was obscured in the KBGgrove, as the scrub species were abundant, indicating a scrub woodland formation.PKP and KLM were characterised by the abundance of a few species. The presenceof a stout liana of Secamone emetica (gbh 35cm), the robustness of Cretaeva magna (gbh 220cm), Syzigium cumini (gbh 207.45cm), P. suberifolium (gbh 128.7cm) and Tamarindus indica (gbh 250cm), and survival of evergreen species like A.elaeagnoidea and Pamburus missionis isbotanically significant; Polyalthia suberosa is a raretaxon found only within the groves. The persistence of the groves until thepresent time is a testimony to the sacred grove status enjoyed by them.  相似文献   

5.
《Ecological Indicators》2008,8(5):657-663
Northeastern region (NER) of India, one of the largest reserves of forests in India has so far been studied with a view to map the distribution of species or modeling the disturbance regimes and richness analysis. The present study focuses on the importance of regional level studies where the entire NER which is under the threat of forest fragmentation and degradation, is been assessed. In the present study, six historical data sets generated from remote sensing data (1972, 1982, 1987, 1989, 1993 and 1999) are used to assess forest cover loss, shape index and entropy to the degree of forest fragmentation over a multi-decadal period. The assessments have been carried out in the open (40–10% canopy density) and close (>40% canopy density) forest cover classes. The range of shape index and deviation from the actual mean in open forest and closed forest were computed separately. The patches among two categories were further analyzed based on patch area into six classes; ranging from <1 km2 to >500 km2. This also indicates variability of the forest patches. It is noteworthy that patches of area within 1–10 km2 and 10–50 km2 have been severely fragmented. This loss could be attributed to the shifting cultivation practice where the patches of moderate size are cultivated by group of families. The present study could give an insight to the patch configuration and composition in terms of shape index and the Shannon's entropy index.  相似文献   

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7.
Brachiopods from the Devonian of northeastern Russia are described: Eoprokopia gen. nov., with the type species E. aequalis sp. nov. (subfamily Prokopiinae, order Orthida); Davoustia settedabanica sp. nov. and D. verkhojanica sp. nov. (family Anopliidae, order Chonetida); and Alkhovikovia gen. nov. with the type species A. libera sp. nov. and A. importuna sp. nov. and Tikhyspirifer gen. nov. with the type species T. globosus sp. nov. (subfamily Rhynchospiriferinae, order Spiriferida).  相似文献   

8.
The genetic variability in Indian populations is examined on the basis of the study of Tf, Gc, Gm, and Km polymorphisms. This variability is not associated with fluctuations, but is related to population history (mainly to migrations, hybrydization and caste endogamy). When genetic distances are calculated, Northern, Southern and Western Indian poplations show closer resemblances to Western Asian populations, while Eastern Indian populations are more similar to Mongoloid peoples.  相似文献   

9.
Brachiopods of the order Orthida from the Lower and Middle Devonian of northeastern Russia: Skenidium diversus Baranov (family Skenidiidae); Datnia gen. nov., with the type species D. asiatica sp. nov. (subfamily Prokopiinae); Janzhinshinia gen. nov., with the type species J. datnensis sp. nov. (subfamily Isorthinae); Cortezorthis chobotchalensis (Alekseeva) (subfamily Cortezorthinae); Elenia gen. nov., with the type species E. gerensis sp. nov. (family Dicoelosiidae); Seimtchania communis (family Seimtchaniidae); Simakovia gen. nov., with the type species S. rara sp. nov. (family Draboviidae); Schizophoria distenta sp. nov., S. grande Baranov, S. striatula (Schlotheim) (family Schizophoriinae); and Hypsomionia sinsera Baranov (family Hypsomioniidae) are described.  相似文献   

10.
Exchange of information between bacteria via physical signals, referred to as “distant interactions” (DI), is the subject of this review. All cases of DI reported to date are discussed, as well as the history of these studies and the place of DI in bacterial communication. Bacterial DI are a particular case of DI occurring in nature (in plants, animals, and fungi). Along with the chemical signals of intracellular communications, DI play a significant role in the life of microorganisms, especially during critical and transitional periods.  相似文献   

11.
Hepatitis C is an emerging infection in India and an important pathogen causing liver disease in India. The high risk of chronicity of this blood-borne infection and its association with hepatocellular carcinoma underscores its public health importance. Blood transfusion and unsafe therapeutic interventions by infected needles are two preventable modalities of spread of hepatitis C infection. In addition, risk factor modification by reducing the number of intravenous drug users will help curtail the prevalence of this infection. This review summarizes the extent, nature and implications of this relatively new pathogen in causing disease in India.  相似文献   

12.
Nitrogen is one of the major plant nutrients without which the agricultural production is not possible. Nitrogen use in Indian agriculture was nearly 55000 tons in 1950-1951 that increased to 11.31 million tons in 2001-2002. The total food production of the country has also experienced the similar increase from 50.83 to 222 million tons in the respective years. Interestingly the N fertilizer consumption of India remained almost constant during the last six years indicating the possibility of reducing N consumption. The highest N consumption is in North zone owing to the introduction of rice-wheat cropping system followed by West, South and East.The N use efficiency has been reported to be varying between 30% to 50% depending on the crops and the management. But in most of the cases, N use efficiency has been calculated based on the total N removed by the crops (above ground part only) ignoring the N content left in the roots. It has been observed in controlled experiments that the total N uptake by roots varied from 18% to 44% of the total N removed by the above ground parts, i.e. grain and straw. If the root N is also accounted, the N use efficiency will be higher than reported. The management of other organic sources has to be improved so as to increase the fertilizer use efficiency as well as to check the direct release of N in the atmosphere. In this review all these issues will be dealt.  相似文献   

13.
During FAO Project NEP/85/011 a methodology was developed for His Majesties Government Department of National Parks and Wildlife Conservation (HMG DNPWC) to determine the impact of lifestock and wild ungulates on condition and physiognomy of alpine grasslands and to derive parametrical relationships between livestock/wildlife distribution and grassland condition.Between Nov. 1986 and March 1988 eight surveys, lasting from 2–9 weeks were undertaken in various regions of central and eastern Nepal. The comparison of three climatically similar areas (Hinku-Hongu, Sagarmatha, Langtang) showed significant differences in the condition (e.g. grass cover, grass height, bare topsoil, biomass) and physiognomy (vegetation composition) of alpine grasslands. These differences seemed to be not so much a function of ungulate density, but were mainly determined by grazing duration, i.e. winter grazing as well as topographical features.Overgrazed areas with a decrease of graminees and an increase of unpalatable shrubs (e.g. Rhododendron anthopogon, Berberis sp.) and herbs (Euphorbia wallichii and E. longifolia, Iris sp.) were particularly abundant in the vicinity of villages. Productivity of grasslands seemed to be highest at altitudes between 3400 and 4000 m ab. S.L. Here grass species showed highest coverage, shrubs and herbs only moderate values. Habitat utilisation of lifestock (cattle, water buffalo, yak, hybrids, goats and sheep) as well as of wild ungulates, such as thar (Hemitragus jemlahicus), bharal (Pseudois nayaur), goral (Nemorhaedus goral goral) and serau (Capricornis sumatraensis tahr) were compared. Productivity (biomass and grass coverage) of grasslands could be correlated with thar density.Differences of utilisation patterns between wild ungulates e.g. bharal and thar, but also between livestock and thar suggested, that some form of competitive exclusion is operating. With the increase of wild ungulates in Sagarmatha N.P., due to protection, conflicts with livestock grazing were evident.In tourist areas, changes in the structure of lifestock populations-mainly as a response to tourism-, have lead to decreasing utilisation of high alpine pastures (>4000 m a S.L.). This pattern also reflects human emigration rates of up to 12% annually. Whereas this does not necessarily benefit the upper regions, it does increase grazing problems in lower regions, in particular the grazing of forests.Two examples of stepwise multiple regression analysis are given to detect parametrical relationships between different numbers and combinations of independent variables. Biomass as well as lifestock numbers could be predicted accurately (r=0.70 (0.84), 0.001相似文献   

14.

Background

Several studies have demonstrated a fundamental role for the HLA in the susceptibility of, or protection to, type 1 diabetes mellitus (T1DM). However, this has not been adequately studied in Asian Indian populations. To assess the frequency of HLA class II (DPA1, DPB1, DQA1, DQB1 and DRB1) associated to susceptibility or protection toT1DM in a Bengali population of India with diabetes.

Results

Single nucleotide polymorphism study. The HLA genotyping was performed by a polymerase chain reaction followed by their HLA-DP, DQ, and DRB1 genotypes and haplotypes by sequencing method. The results are studied by Plink software. The χ2 tests were used for the inferential statistics. To our knowledge, this study is the first of a kind which has attempted to check the HLA association with T1DM by SNPs analysis. The study recruited 151 patients with T1DM and same number of ethno-linguistic, sex matched non-diabetic controls. The present study found a significant SNP rs7990 of HLA-DQA1 (p = 0.009) negative correlation, again indicating that risk from HLA is considerably more with T1DM.

Conclusions

This study demonstrates that the HLA class-II alleles play a major role in genetic basis of T1DM.  相似文献   

15.
Nitrogen is one of the major plant nutrients without which the agricultural production is not possible. Nitrogen use in Indian agriculture was nearly 55000 tons in 1950-1951 that increased to 11.31 million tons in 2001 -2002. The total food production of the country has also experienced the similar increase from 50.83 to 222 million tons in the respective years. Interestingly the N fertilizer consumption of India remained almost constant during the last six years indicating the possibility of reducing N consumption. The highest N consumption is in North zone owing to the introduction of rice-wheat cropping system followed by West, South and East. The N use efficiency has been reported to be varying between 30% to 50% depending on the crops and the management. But in most of the cases, N use efficiency has been calculated based on the total N removed by the crops (above ground part only) ignoring the N content left in the roots. It has been observed in controlled experiments that the total N uptake by roots varied from 18% to 44% of the total N removed by the above ground parts, i.e. grain and straw. If the root N is also accounted, the N use efficiency will be higher than reported. The management of other organic sources has to be improved so as to increase the fertilizer use efficiency as well as to check the direct release of N in the atmosphere. In this review all these issues will be dealt.  相似文献   

16.
This article examines the biocultural dynamics of social discrimination and physical disfigurement among people with leprosy, or Hansen's disease (HD), in Banaras, northern India. Based on the narratives and observations ofpeople living in colony and street settings, I trace three destructive processes by which the social stigmata of leprosy become physically expressed. First, strategies of concealment further the progression and spread of HD through late detection and undertreatment. Second, the internalization of stigma can lead to bodily dissociation and injury through self-neglect. Finally, some people intentionally seek injuries under conditions of desperate poverty. As a result of such mortification processes, these people came to embody, quite literally, the prejudices that exacerbated their condition in the first place.  相似文献   

17.
B. K. Sharma 《Hydrobiologia》1980,70(3):225-233
This paper deals with 36 species of monogonont rotifers (belonging to 10 eurotatorien families) collected from Sambalpur (Orissa State) in Eastern India. Of the reported taxa, 15 species have been added as new records to the previous list from this region while one species represents a new record from this country.  相似文献   

18.
Morphological composition of the people of India   总被引:1,自引:0,他引:1  
  相似文献   

19.
20.
Commercialization of plant tissue culture in India   总被引:2,自引:0,他引:2  
Commercial application of plant tissue culture started in USA with micropropagation of orchids in 1970s. It has seen tremendous expansion globally from 1985 to 1990 in the number of production units as well as the number of plants produced. With an estimated global market of 15 billion US dollars per annum for tissue cultured products, even with exponential expansion in the industry, the demand far exceeds production, leaving enough scope for expansion. This industry appears to be undergoing a pause in growth presently in developed countries as it is finding difficult to remain cost–effective. In US, only half the production capacity is being utilized currently due to high labour costs. In developing countries, with lower wage scales, plants are being produced at much cheaper rates. Indian micropropagation industry, though a late starter by almost a decade, compared to its western counterparts, has expanded exponentially from 5 million annual capacity in 1988 to 190 million in 1996. The facilities now created are at par with the best in leading countries like the Netherlands and USA. To remain in profitable business and to earn the much needed foreign exchange, Indian units need to judiciously mix steady revenue generating items with unique speciality items based on demand in domestic and international markets. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

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