Impact of land-use changes and sedimentation on the Muhammad Nur Reservoir, South Kalimantan, Indonesia

The Muhammad Nur Reservoir (MNR) is a major multipurpose reservoir located on the Riam Kanan River in the Indonesian Province of South Kalimantan. The MNR has a high sediment trap efficiency and there is concern that accelerated erosion in the catchment, resulting from inappropriate land use, poses a significant threat to the storage capacity and effective life span of the reservoir. Furthermore, on-going deforestation of large parts of the catchment may have changed the inflow pattern to the reservoir. This paper uses data from fieldwork and published information from different sources to examine the extent of erosion and sedimentation in the catchment and the sediment delivery to the reservoir. Water level variations in the reservoir over a 22-year period are examined for changes that might indicate an alteration of the hydrologic balance in the catchment.     

Biology and management of the fast‐emerging threat of broomrape in rapeseed–mustard

Broomrapes (Phelipanche and Orobanche spp.) are obligate root parasites of the family Orobanchaceae. The natural variation in Orobanchaceae exists in plants involving Triphysaria versicolor (facultative hemiparasite), Striga hermonthica (obligate hemiparasite) and Phelipanche aegyptiaca, formerly Orobanche aegyptiaca (holoparasite). The family Orobanchaceae has 90 genera. The four major parasitic species of broomrape are Phelipanche ramosa in the Brassicas, especially in rapeseed, Phelipanche cernua in tobacco and sunflower, P. aegyptiaca in solanacious crops and in Brassica juncea and Phelipanche crenata in leguminous crops. They are prevalent, infesting nearly 1.2% of the world's arable land. In India, P. ramosa and P. aegyptiaca cause severe infestations of Brassica and have threatened its cultivation in major growing areas. In addition, a single broomrape plant can release >100 000 seeds that remain viable for decades in the soil. This provides the parasite with a great genetic adaptability to environmental changes, including host resistance, agronomical practices and herbicide treatments. Different control measures, such as manual weeding, herbicide applications, solarization, crop rotation and integrated broomrape management practices, have been proposed in order to reduce the broomrape menace and improve yields in farmers' fields. Breeding for broomrape resistance also could be an economic, feasible and environmental friendly control method. The present article reviews the current status of research on broomrape in India and abroad, as well as suggests strategies for its effective management.     

TREATED EFFLUENT AND SALINE WATER IRRIGATION INFLUENCES SOIL PROPERTIES,YIELD, WATER PRODUCTIVITY AND SODIUM CONTENT OF SNOW PEAS AND CELERY

To determine the effects of irrigation water quality, plants were irrigated with normal potable water [0.25 dS m^?1 electrical conductivity (EC), 25 mg L^?1 sodium (Na), 55 mg L^?1 chloride (Cl)], treated effluent (0.94 dS m^?1 EC, 122 mg L^?1 Na, 143 mg L^?1 Cl) and saline water with low salinity (1.24 dS m^?1 EC, 144 mg L^?1 Na and 358 mg L^?1 Cl) and high salinity (2.19 dS m^?1 EC, 264 mg L ^?1Na and 662 mg L^?1 Cl) for snow peas, and high salinity (3.07 dS m^?1 EC, 383 mg L^?1 Na and 965 mg L^?1 Cl) and very high salinity (5.83 dS m^?1 EC, 741 mg L^?1 Na and 1876 mg L^?1 Cl) for celery. The greater salts build up in the soil and ion toxicity (Cl and Na) with saline water irrigation contributed to significantly greater reduction in root and shoot biomass, water use, yield and water productivity (yield kg kL^?1 of water used) of snow peas and celery compared with treated effluent and potable water irrigation. There was 8%, 56% and 74% reduction in celery yield respectively with treated effluent, high salinity and very high salinity saline water irrigation compared with potable water irrigation. The Na concentration in snow peas shoots increased by 54%, 234% and 501% with treated effluent, low and high salinity saline water irrigation. Similarly, the increases in Na concentration in celery shoots were 19%, 35% and 82%. The treated effluent irrigation also resulted in a significant increase in soil EC, nitrogen (N) and phosphorus (P) content compared with potable water irrigation. The heavy metals besides salts build up appears to have contributed to yield reductions with treated effluent irrigation. The study reveals strong implications for the use of saline water and treated effluent for irrigation of snow peas and celery. The salt build up within the root zone and soil environment would be critical in the long-run with the use of saline water and treated effluent for irrigation of crops. To minimize the salinity level in rhizosphere, an alternate irrigation of potable water with treated effluent or low salinity level water may be better option.     

Ethno-medicinal plants used by Bengali communities in Tripura,northeast India

Northeastern India has high medicinal plant diversity due to variance in topography and physiognomy. We documented the uses of various medicinal plants by the Bengali people of West district and South district of Tripura state for their own health care as well as for domesti-cated animals. Based on semi structured interviews, group discussions and information from local informants, a total of 93 species of medicinal plants of 52 families and 83 genera were documented. These plants were used to treat more than 55 different human diseases and 6 diseases of livestock. Sixty-eight plant species were used singly and the rest were used in combination with other species for therapeutic formulations of various diseases. Leaves of plants were most often used for most of the ethnobotanical preparations. Maximum consensus value of 96% was recorded for Chromolaena odorata （L.） King ＆amp;H. Rob., and the mini-mum was 15%for Bambusa balcooa Robx. Of the 93 plant species, 75 species showed pharmacological properties. Prospects for augmenting existing knowledge and enhancing the use of traditional medicinal plants are discussed.     

Long-Term Effects of Different Passages of Vehicular Traffic on Soil Properties and Carbon Storage of a Crosby Silt Loam in USA

The passage of vehicles with heavy axle loads causes soil compaction, and this adversely affects soil properties and crop yield.The adverse effects can persist for several years due to significant changes in key soil properties. However, the mechanisms of the aforementioned effects are not well understood for conservation agriculture(CA)(e.g., no-till(NT)) wherein the use of heavy machinery is considerably common. Therefore, known compaction forces(0 Mg load for compaction(NT-0, control), two passages of 2.5 Mg water wagon axle load(NT-2), and four passages of 2.5 Mg water wagon axle load(NT-4)) were applied to all the plots annually for 20 consecutive years. The experiment was established in 1997 at the Waterman Agricultural and Natural Resources Laboratory(WANRL), Ohio State University, Columbus, Ohio. Each treatment was replicated thrice. Soil samples were obtained in November2016 to determine the effects of variations in the axle load and vehicular passages on carbon(C) and nitrogen(N) storage and selected soil properties of a Crosby silt loam soil under NT-based corn-soybean rotation with residue retention in Central Ohio, USA. Three locations were also randomly selected in an adjoining natural woodlot(WL) soil plot and sampled(30 m away from the compaction field) to compare the effects of vehicular traffic on soil under NT with WL soil. Results revealed that soil bulk density(ρb) and total porosity at 0–10 and 10–20 cm depths were not affected by the passages of vehicular traffic for 20 years under the NT system.The penetration resistance(PR)(1.86 and 2.03 MPa at 0–10 and 10–20 cm soil depths, respectively) was significantly higher under NT-4 compared with that under other treatments. Saturated hydraulic conductivity at 0–10 and 10–20 cm soil depths ranged from19.7 to 31.4 and 18.5 to 29.5 mm d~(-1), respectively, across all the treatments. The proportion of macroaggregates( 0.25 mm) and microaggregates( 0.25 mm), mean weight diameter and geometric mean diameter of aggregates, pH, electrical conductivity, and C and N contents and storage did not differ significantly between the treatments at either of the sampling soil depths. The data indicated that 2 to 4 passages of vehicles with 2.5 Mg of axle load did not cause significant compaction of the Crosby silt loam under NT compared with that under natural WL. Therefore, the continuous cultivation of row crops with NT and residue retention is feasible with passages of vehicular traffic for well-drained soils in Central Ohio.     

Characterization and pathogenicity studies of Vibrio parahaemolyticus isolated from diseased freshwater prawn, Macrobrachium rosenbergii (de Man)

Vibrio parahaemolyticus, an important pathogen of freshwater prawn, Macrobrachium rosenbergii causes high mortality. Four strains of V. parahaemolyticus were isolated from the gill, haepatopancreas, hemolymph and carapace of diseased prawn. The species were characterized based on biochemical and serological tests. On performing an antibiotic assay, these strains were found to be highly susceptible to cephalaxin, tetracycline and erythomycin. During the in vitro pathogenicity test, all the strains were found to be positive to the Congo red binding assay and to be haemolytic in nature, whereas an in vivo pathogenicity test revealed that 2 × 10⁹ CFUs mL^?1of bacteria induced disease symptoms such as black colouration on the carapace, red discolouration of the exoskeleton and loss of appendages within 6 days and 80% mortality. In histopathological studies, a prominent necrosis was seen in gill lamellae, and branchial arches were thickened at places due to hyperplasia and haemocytic infiltration. Hepatopancreatic tissue showed dilation of tubules, vacuolation of hepatocytes and marked necrosis in acinar cells. Development of an immunological technique for the detection and screening of V. parahaemolyticus infection and its treatment is highly important in freshwater prawn aquaculture.     

Evidence for a great medieval earthquake (~1100 A.D.) in the central Himalayas, Nepal

The Himalayan orogen has produced three thrust earthquakes with moment magnitude (Mw) 7.8 to 8.5 during the past century, yet no surface ruptures associated with these great earthquakes have been documented. Here, we present paleoseismic evidence from east central Nepal that, since approximately 700 A.D., a single earthquake ruptured the Frontal Thrust fault at approximately 1100 A.D., with a surface displacement of approximately 17 (+5/-3) meters and a lateral extent and size that could have exceeded 240 kilometers and approximately Mw 8.8, respectively. Ruptures associated with Mw <8.2 events would contribute to the frontal Himalayas folding but would stop before reaching the surface. These findings could require substantial modifications to current regional seismic hazard models.     

A high cysteine containing thiol proteinase from the latex of Ervatamia heyneana: purification and comparison with ervatamin B and C from Ervatamia coronaria

A cysteine protease, with a high cysteine content and a high degree of amino terminal sequence homology with ervatamins B and C, has been purified from the latex of Ervatamia heyneana (Family Apocynaceae). The enzyme designated as heynein (M(r) = 23 kDa) has a comparatively high cysteine content (11), high isoelectric point (10.8), and high stability against pH (2.5-11.5), temperature (63 degrees C, 15 min), strong denaturants, and organic solvents. The enzyme has high specific activities for natural substrates such as casein and azoalbumin. The pH and temperature optima are pH 8.0-8.5 and 52 +/- 2 degrees C, respectively. Hydrolysis of synthetic substrates and digestion of bovine serum albumin confirm a distinct specificity of heynein as compared to ervatamins and papain. Also, heynein has distinct immunogenicity as monitored by enzyme-linked immunosorbent assay and Ouchterlony's double immunodiffusion. Strong enzyme activation by reducing agents such as beta-mercaptoethanol, dithiothreitol, and strong enzyme inhibition by thiol proteinase inhibitors such as E-64 and iodoacetic acid have evidenced heynein to be a cysteine protease. High stability, specific activity, and easy purification may make heynein a potential protease for food and biotechnology applications.