Abstract: Mustard aphid (Lipaphis erysimi. Kalt.) has been reported as one of the devastating pests in realizing the potential productivity of Indian mustard (Brassica juncea L.). The experiment was carried out to assess the yield losses in mustard due to mustard aphids grown in different thermal environments under protected and unprotected conditions. To provide different thermal environments the crop was sown on 5 dates i.e. 08, 18 and 28 November and 08 and 18 December during winter seasons of 1995- 96, 1996-97 and 1997-98. It was observed that yield attributes and yield of mustard was significantly decreased in delayed sowing even under protected conditions. On an average maximum seed yield of 1409 kg/ha was harvested when the crop was sown on 08 November under protected condition, while only 279 kg/ha seed yield was recorded under unprotected condition. Similarly the yield attributes and yields drastically reduced under unprotected condition as compared to protected one in all the thermal environments. On the mean basis 80.6, 81.4, 95.2 and 97.6 per cent yield loss was observed under unprotected condition as compared to protected condition in 08, 18, 28 November and 08 and 18 December sowing, respectively. It was also observed that the critical period of mustard exposure to aphids was found to be the 3rd week after aphid appearance when the crop was in flowering stage and hence the control measures have to be initiated before flowering. There was not much difference in natural aphid population/plant in the crop sown up to end of November while the aphid population increased suddenly in December sown crop.

Keywords: mustard, Lipaphis erysimi, avoidable losses, yield

Abstract: The present study discusses the light trapping of insects depending on the environmental illumination, twilight polarization phenomena and the moon phases. The trapping data were taken of Hungarian national light-trap network. The important results are the followings: The Babinet-point, a polarization free spot of the sky at twilight, can be a role of orientation of insects. The height of the Moon above the horizon is in negative correlation with the number of the caught insects. The maximum individual number of species was collected at various moon phases.

Keywords: light-trap, collecting distance, Babinet-point, moon phases

Abstract: A study was conducted to evaluate the ash content as a function of time of vermicomposting and the moisture content which plays a significant role in the process. The data revealed a linear relationship between the ash content and time in the effective range of the vermicomposting duration. The model parameters of this linear relationship also have linear correlation with the moisture content. Through substitutions, a generalized predictive model for the ash content has been evolved in terms of the duration of vermicomposting and the moistures contents. A plot of the predictive and experimentally observed values indicated a high robustness of predictive model. The study also showed that a moisture content of 80% is optimum for stabilization of waste in minimum processing time.

Keywords: earthworm, ash content, moisture content, waste management, modeling

Abstract: Of a great concern, the huge amount of waste rubber materials can cause environmental problems. Various methods have been proposed to solve this proplem. One of those is the biodegradation of it by microorganisms. Bacteria able to degrade and use natural rubber latex as the sole source of carbon and energy were isolated from different ecosystems. 42 rubber-degrading bacteria were isolated. Out of these isolates, 31 were identified as Streptomyces, 5 as Micromonospora, 3 as Actinoplanes, 2 as Gordona and 1 as Nocardia species. All rubber-degrading isolates were identified as members of Actinobacteria which is a large group of mycelium forming Gram-positive bacteria. Interestingly no Gram-negative bacteria could be isolated.

Keywords: Streptomyces, Micromonospora, rubber degradation, isolation

Abstract: Phosphomonoeaterase (PMEase) and phosphodiesterase (PDEase) activity was studied in the cyanobacterial cultures of Chroococcidiopsis isolated from two diverse cryptoendolithic habitats of Antarctic and Arizona. Because this organism is found within the rocks it appears that phosphorus metabolism by alkaline phosphatase activity is a key factor to sustain growth of these organisms in that state, there being no other source of external P except in bound form in the rocks. The main findings in this paper show that specific pH and temperature regulate the PMEase and PDEase activities studied with different substrates in isolated of Chroococcidiopsis 1 and 2 although values were vastly different. The pH and temperature optima for phosphatase activity (PMEase and PDEase) of Chroococcidiopsis 1 and 2 were 9.5, 20 °C and 8.5, 40 °C respectively. It needs mentioning here that although the pH optimum for the enzyme activities in the Antarctic rock samples was the same i.e. 9.5 there was a striking difference in the temperature optimum in which maximum activity of both enzymes were recorded at 5 °C. A very crucial role of light and dark conditions were important for the enzyme activity and differed to a significant extent when compared with naturally occurring organisms in the Antarctic rocks. Low light fluxes of about 8 μmol photon m-2s-1 showed higher PMEase and PDEase activity then total dark conditions in the Chroococcidiopsis -1 culture. However under natural conditions when this organism is found within the rocks 8-μmol photon m-2s-1 was found to be inhibitory and dark conditions gave higher PMEase and PDEase activity. Arizona rock samples containing Chroococcidiopsis -2 however did not show dark stimulation. Increase in light intensity from 8 μmol photon m-2s-1 to 60 μmol photon m-2s-1 maintained in the culture room increased the PMEase and PDEase activity of both cultures. The unique light and temperature responses for PMEase and PDEase activities in Chroococcidiopsis-1 found within the Antarctic rocks are unique. It points to some change in the cells probably by producing some cryoprotectant which protects the enzymes from becoming non functional at low temperatures. It also indicates that exposure to light fluxes as low as 8 μmol photon m-2s-1 can probably alter the properties of the enzymes thus reducing its activity compared to total darkness.

Keywords: endolithic, cyanobacteria, phosphomonoesterase, Antarctic, Arizona

Abstract: This paper reviews applications of remote sensing and geographic information systems (GIS) techniques to the assessment of tropical waters. These applications are discussed in the context of specific management objectives and sensors used. The need to monitor the spreading patterns of weeds in the tropical waters, land-use changes in the areas surrounding them, change detection, disappearance of wetlands, productivity and nutrient status, in order to establish trends and subsequently develop predictive models to facilitate effective management, is highlighted. GIS capability can be used to link ecological information with the management decisions of these waters. Remote sensing provides useful information in the form of satellite images and aerial photographs that can be integrated and analyzed in a GIS to provide useful spatial information and temporal changes over large geographic areas affecting the structure and function of tropical waters.

Keywords: GIS, remote sensing, sustainable management

Abstract: In Udvardy classification of introducing geographical biosphere provinces, the Miankaleh biosphere reserve of Iran, located in the southern coast of the Caspian Sea, has been expressed as mixed mountainous biome system. As the Udvardy classification, in large scale, is for national and regional use, it may not be able to separate the various kinds of existing habitats in a Biogeographical Province. That is why to prove the Udvardy classification theory and to investigate the probable disorder in it, by recognition of flora, the vegetation of the reserve has been studied, considering the ecological points of view. In the present research, the cluster analysis for classification of plant community and the ordination method for analysis of environmental (water table level and electrical conductivity of soil and water) relationships with plant communities have been used. The floras of the region, with over 200 species, with the origin of Euro- Siberian and Irano- Touranian, have been recognized and the presences of plant communities have been related to water table level and salinity of soil and water. In relation to Udvardy theory it seems that based on the existing and paleoecological documents of 1905, before fragmentation of Miankaleh winter and Alborz mountainous habitats, because of the urban developments, the place of the biosphere reserve of Miankaleh, as a unit, was a mixed mountainous biome.

Keywords: Iran, biosphere reserve, Udvardy, Miankaleh, geographical province, Caspian Sea.

Abstract: A study examining correlations between fruit trees physiological and visual properties collected by remote sensing technology started at Budapest University of Economic Sciences and Public Administration, Faculty of Horticultural Science, together with Kyoto University and Wakayama Research Center of Agriculture, Forestry and Fisheries, Fruit Tree Experiment Station (Japan). Experimental plant was Satsuma mandarin (Citrus unshiu MARC. var. satsuma), the physiological property to examine was leaf water potential, which correlates with the sugar content of mandarin fruit according to preceding studies. Large amount of visual information had been recorded at ground level and was processed by the methods of image analysis and biometry. Under field conditions images of given leaves showed different type of reflectance frequency distribution. These distributions often could be identified as normal distribution, however left skewed, right skewed and bimodal distributions also occurred even partially shifted out of the perceptive range of the measuring device. Comparison of the applied biometric methods was analyzed to adjust with the natural field conditions, hardware and software features. Results showed that normal distribution model could be applied for analyzing data obtained at optimal conditions, however these phenomena under natural field conditions could often be described better when weighted averaging methods were applied on frequency distributions.

Keywords: image analysis, satsumas, mandarin, multispectral, NDVI

Abstract: It is necessary to keep diversity in livestock as well as in wild life. Decreased variety in wild life leads to extinction of species whereas in the aspect of livestock it may lead to hunger. This can be because of inbreeding depression or lost genes that are still needed. Different lines of livestock should be kept to prepare for a future that requires attributes not needed today. The different lines can be determined using factor analysis. Separate lines then can be merged by random mating; making way to a herd that has the variance of the original herd. Alternatively, biological material can be stored cryogenically. Live animals can adapt to environmental changes in time and may prove more useful though keeping live animals may cost more than cryogenic storage of biological material.

Keywords: cryogenic storage, livestock, biotecnology, biodiversity, sperm, oocites

Abstract: Present review paper tries to show the main aspects of migration of fishes in Romanian sector of Danube River. The Danube River has a large hydrographical basin, being the second largest river in Europe. The main channel flows trough seven European countries. There are many species of fish that annually or seasonally migrate either for reproduction or feeding in different areas of Danube and its main tributaries.

Keywords: migration, fish, capture dynamic, Danube, fulton factor, protection