An assessment of the genetic integrity of ex situ germplasm collections of three endangered species of Coffea from Madagascar: implications for the management of field germplasm collections     

Sarada Krishnan  Tom A. Ranker  Aaron P. Davis  Jean Jacques Rakotomalala 《Genetic Resources and Crop Evolution》2013,60(3):1021-1036

Madagascar has 59 species of Coffea, of which 42 are listed as Critically Endangered, Endangered, or Vulnerable by criteria of the Red List Category system of the World Conservation Union. In an attempt to assess the conservation value of ex situ collections of Malagasy coffee species, a study was undertaken using the field genebank collections maintained at the Kianjavato Coffee Research Station. Three species were selected for this purpose, C. kianjavatensis, C. montis-sacri, and C. vatovavyensis, and for comparative purposes extant, in situ populations of the same species were studied. Parentage analyses of ex situ propagated offspring of C. kianjavatensis and C. montis-sacri were performed to assess if crossing with other Coffea species maintained in the field genebank is compromising the genetic integrity of the collection. For these three species, higher genetic diversity was observed in the ex situ populations compared to the in situ populations, highlighting the importance of preserving the plants currently in ex situ collections. Parentage analyses of seed-propagated offspring of C. kianjavatensis and C. montis-sacri revealed that cross contamination with pollen from other Coffea species in the ex situ field genebank is occurring. These results have significant implications for the conservation management of wild Coffea species and for the management of ex situ genebanks.  相似文献   

Assessing soil spatial variability and delineating site-specific management zones for a coastal saline land in eastern India     

Tripathi Rahul  Nayak Amaresh Kumar  Dhal Biswaranjan  Shahid Mohammad  Lal Banwari  Gautam Priyanka 《Archives of Agronomy and Soil Science》2013,59(13):1775-1787

ABSTRACT

The present study was to delineate management zones (MZs) in salt affected Mahakalpada block in eastern India by capturing both spatial variability of soil parameters along with satellite derived Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI). Grid wise 237 soil samples collected from the study area were analyzed and spatial maps were generated for physicochemical properties, DTPA extractable micronutrients, i.e. iron, zinc, copper, and manganese and major nutrients, i.e. available nitrogen (AN), phosphorous (AP), and potassium (AK). Soil electrical conductivity and AK showed a high CV of 100% and 56.7%, respectively. Principal component analysis was performed using the soil spatial maps, NDVI and EVI maps and only four principal components which produced eigenvalues > 1 and accounting for 75.4% of the total variability were retained for further analysis. Further, fuzzy c-mean clustering was used to delineate the MZs based on fuzzy performance index (FPI) and normalized classification entropy (NCE) was used for identifying the three MZs. There was a significant difference between MZ1 and MZ2 for all the variables except AN and EVI whereas all the variables were significantly different between MZ1 and MZ3 highlighting the usefulness of MZs delineation technique for site-specific nutrient management.  相似文献   

The role of carbon dioxide during the onset of Antarctic glaciation     

Pagani M  Huber M  Liu Z  Bohaty SM  Henderiks J  Sijp W  Krishnan S  DeConto RM 《Science (New York, N.Y.)》2011,334(6060):1261-1264

Earth's modern climate, characterized by polar ice sheets and large equator-to-pole temperature gradients, is rooted in environmental changes that promoted Antarctic glaciation ~33.7 million years ago. Onset of Antarctic glaciation reflects a critical tipping point for Earth's climate and provides a framework for investigating the role of atmospheric carbon dioxide (CO(2)) during major climatic change. Previously published records of alkenone-based CO(2) from high- and low-latitude ocean localities suggested that CO(2) increased during glaciation, in contradiction to theory. Here, we further investigate alkenone records and demonstrate that Antarctic and subantarctic data overestimate atmospheric CO(2) levels, biasing long-term trends. Our results show that CO(2) declined before and during Antarctic glaciation and support a substantial CO(2) decrease as the primary agent forcing Antarctic glaciation, consistent with model-derived CO(2) thresholds.  相似文献   

Patterns in abundance and diversity of faecally dispersed parasites of tiger in Tadoba National Park,central India     

Rahul?R?Marathe  Shantanu?S?Goel  Sachin?P?Ranade  Maithili?M?Jog  Milind?G?WatveEmail author 《BMC ecology》2002,2(1):6

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Chemical characterization of high-yielding varieties of cashew (Anacardium occidentale)     

K. V. Nagaraja  V. M. Krishnan Nampoothiri 《Plant foods for human nutrition (Dordrecht, Netherlands)》1986,36(3):201-206

Cashew apples and kernels from sixteen high-yielding varieties were chemically characterized. Protein, starch, amino acids and sodium contents in cashew kernels did not vary significantly among the high-yielding varieties. Reducing sugar content in the kernel was negligible compared to total sugar. Ascorbic acid, amino acid, phenol and tannin contents in cashew apple showed a significant variation among high-yielding varieties. Non-reducing sugar content in cashew apples was negligible. Varieties M 6/1, Bla 256-1, M 10/4 and M 44/3 appeared to be better for apple juice extraction because of their low tannin content. No varietal difference was noticed with respect to qualitative composition of sugars, organic acids and phenols.CPCRI Contribution No. 459  相似文献   

Community-based forest management and its role in improving forest conditions in Nepal   总被引：1，自引：1，他引：0  

Anup Gurung  Rajesh Bista  Rahul Karki  Shanti Shrestha  Dharam Uprety  Sang-Eun Oh 《Small-Scale Forestry》2013,12(3):377-388

The status of forest conditions before and after intervention of the forestry projects in community forest in three districts of Nepal is examined. Benefits are observed from the adoption of adaptive collaborative management and collective learning and action research in three sampled districts. The adoption of regular silvicultural treatments has increased the availability of forest products to local users. Moreover, improved forest condition and smallholder livelihoods have improved, as has environmental sustainability. However, the community forestry program has several limitations and shortcomings. Elite capture, social disparity, inequitable benefit-sharing and exclusion of poor and marginalized groups from the community forestry program are notable challenges to be solved in coming years. Special attention is needed to make community forestry inclusive with equitable benefit-sharing and a pro-poor focus.  相似文献   

Potential of extracts of the tropical plant Balanites aegyptiaca (L) Del. (Balanitaceae) to control the mealy bug, Maconellicoccus hirsutus (Homoptera: Pseudococcidae)     

Satish V. Patil  Bipinchandra K. Salunke  Chandrashekhar D. Patil  Rahul B. Salunkhe  Pankaj Gavit  Vijay L. Maheshwari 《Crop Protection》2010

The effects of extracts of different parts of the perennial tropical plant Balanites aegyptiaca (L) Del., including various solvent extracts of roots, methanol extracts from leaves, fruits, flowers and roots, partially purified saponins obtained from its roots and a standard saponin were studied on the life cycle (adult longevity, number of eggs, crawlers, adults, weight of adults and % wax content) of a laboratory-reared parthenogenic line of the mealy bug, Maconellicoccus hirsutus (Homoptera: Pseudococcidae). Extracts derived from various parts of B. aegyptiaca (leaves, fruits, flowers, and roots in methanol) affected the life cycle of M. hirsutus with a methanol root extract being the most effective at a concentration of 500 μg ml⁻¹. Partially purified saponin of B. aegyptiaca and the commercial bark saponin extract (Sigma) from Quillaja saponaria at a concentration of 500 μg ml⁻¹ were effective in reducing the longevity of M. hirsutus. Significant reductions in oviposition by M. hirsutus were found for all the extracts at a concentration of 500 μg ml⁻¹. Extracts also affected the number of emerging crawlers, number of adults as well as the weight and wax content of emerging adults. These studies suggest that B. aegyptiaca plant extracts and saponins can be useful botanical insecticides for the protection of crops from mealy bugs.  相似文献   

Studies on life cycle of mealybug, Maconellicoccus hirsutus (Green) (Hemiptera: Pseudococcidae), on different hosts at different constant temperatures     

Satish V. Patil  Chandrashekhar D. Patil  Rahul B. Salunkhe  Vijay L. Maheshwari  Bipinchandra K. Salunke 《Crop Protection》2011,30(12):1553-1556

The life cycle of a laboratory reared parthenogenic line of mealybug, Maconellicoccus hirsutus (Green) (Hemiptera: Pseudococcidae) was investigated on six host plants (Lagenaria siceraria var.clavata, Solanum tuberosum L. var. Kufri Chandramukhi, Praecitrullus fistulosus (Stocks) Pangalo var. MTNH1, Cucurbita pepo var. Styriaca, Triticum aestivum L. var. Lokvan, H. rosa sinensis L.) at five constant temperatures (25, 29, 35, 38, 42 °C). The number of emerging crawlers and adults as well as weight of adults varied with host and temperature. P. fistulosus and H. rosa sinensis were suitable hosts for laboratory rearing of M. hirsutus. However, ease of maintenance of P. fistulosus to produce M. hirsutus under laboratory conditions is an additional advantage compared to using green plants such as H. rosa sinensis. Among the range of constant temperatures, 38 °C was found to be the most favourable for the development and survival of M. hirsutus. These results suggest that P. fistulosus fruits are suitable hosts for laboratory rearing and life cycle studies of M. hirsutus.  相似文献   

Response of a freshwater air-breathing fish, Clarias batrachus to salinity stress: an experimental case for their farming in brackishwater areas in Andaman, India     

Kamal Sarma  K. Prabakaran  P. Krishnan  G. Grinson  A. Anand Kumar 《Aquaculture International》2013,21(1):183-196

The study was conducted to assess the effects of salinity on growth and biochemical composition of freshwater catfish, Clarias batrachus. A static nonrenewable acute toxicity bioassay test was conducted and LC₅₀ of salinity for 96-h exposure to the fingerling (14.5 cm) was 12.52 ‰. Based on these results, two sublethal salinity levels, viz. 4 and 8 ‰ were selected to study the long-term effects of salinity on C. batrachus for a period of 90 days. From the study, it was found that growth and survival rate were less in saline water (4 and 8 ‰). Maximum growth and survival were recorded in freshwater (0 ‰ salinity) and subsequently at 4 and 8 ‰. To assess the biochemical alteration, few important biomarkers were estimated. At the end of 90 days rearing period, glucose level in the brain and blood of C. batrachus was found to decrease with salinity. The level of liver and muscle glycogen in the fish reared at 4 ‰ was lower than that of control. Ascorbic acid in all organs under study was found to decrease with increasing salinity, which was attributed to stress mitigation effect of vitamin C. Acetylcholine esterase (AchE) activity recorded a gradual decrease with increasing salinity. Metabolic enzymes, alkaline phosphatase (ALP) activity and adenosine triphosphosphtase (ATPase) activity also reduced both in liver and muscle tissues with increasing salinity. From the present investigation, it can be concluded that exposure to higher salinity significantly (P < 0.01) affects the growth and physiological response of Clarias batrachus.  相似文献   

Curcumin from Curcuma longa affects the virulence of Pectobacterium wasabiae and P. carotovorum subsp. carotovorum via quorum sensing regulation     

Murugesan Sivaranjani  Subramanian Radhesh Krishnan  Arunachalam Kannappan  Manikandan Ramesh  Arumugam Veera Ravi 《European journal of plant pathology / European Foundation for Plant Pathology》2016,146(4):793-806

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