Abstract: Investigation on the evaluation of certain management schedules against major insect pests of Vigna radiata (L.) Wilczek, was carried out for two crop seasons (July to October 2001 and 2002) at the Agronomy Farm and the Department of Agricultural Zoology and Entomology of Rajasthan College of Agriculture, Maharana Pratap University of Agriculture and Technology, Udaipur, India. The efficacy of Azadirachta indica A. Juss oil and malathion, as first application against aphids, jassids and whiteflies was significantly lower under sole crop of V. radiataI than when it was inter-cropped with maize during both years (2001 and 2002). Among the different treatment schedules as third application, endosulfan was most effective against the pod borers (Maruca testulalis Geyer and Lampides boeticus L.) in both sole crop and the intercrop. During the two-year study (2001 and 2002), the maximum yield of maize and green gram in the inter-cropped pattern and that as sole crop of green gram, as well as the maximum rupee equivalent yield value was recorded for the management schedule comprising release of Chrysoperla carnea 25 DAS, spray of A. indica oil 40 DAS and endosulfan 55 DAS. The lowest yield of V. radiata was recorded under the management schedule comprising three release of Chrysoperla carnea Stephen at 25, 40 and 55 DAS irrespective of the cropping pattern.

Keywords: Management, insect pests, Vigna radiata, Lampides boeticus, Maruca testulalis

Abstract: The total hydrocarbon (THC) levels in the surface waters, sediments and biota in an oil polluted mangrove wetland located in the Niger Delta Nigeria, were studied between November 2001 and October 2002. Result showed elevated THC mean levels in water (23.6 + 4.3mg/l), sediment (386.44 ± 50.28μg/g), Tympanotonus fuscatus (Periwinkle) (449.30 ± 55.42μg/g) and Periophthalmus papillio (Mudskipper) (278.57 ± 34.57μg/g), indicating a polluted environment. THC levels in water at the wellhead stations were above 10mg/l being the maximum recommended limit by the Federal Ministry of Environment (FMENV) Nigeria. There was a pronounced seasonal variability with the highest being in the dry season (P 0.05) due to the higher level of increased oil activity in that season. THC levels in water correlated significantly (r = 0.927) with THC levels in the sediment (P 0.01). The implication is that as the THC remains within the surface water column in relation to the sediment the more the organisms in the environment are impacted. This is shown by the significant correlations (P0.01) of THC between the organisms and their surrounding media. The high levels of THC in the surface water and sediments of these stations suggest that aquatic life water quality may adversely influence biological functions of exposed species, while the level in the Tympanotonus fuscatus and the Periophthalmus papillio calls for concern as it can have some health-risk implications in man who is the final consumer.

Keywords: Molluscs, biota, bioaccumulation, hydrocarbon

Abstract: The present study was undertaken to assess the environmental variation in seed characters and to explore the efficacy of hydrogen peroxide treatment on the germination and seedling traits of sixteen provenances of Pinus roxburghii from Uttarakhand Himalaya. Provenances, which had higher values for seed parameters showed better germination. Soaking the seeds for 24 hours in a solution of H2O2 (1% v/v) had a significant effect on the rate of germination and average germination percentage. About 88.5 % of mean average germination was revealed by the seeds that were treated with H2O2 as compared to the untreated (control) seeds (77.4 %). Simultaneously, H2O2 treatment also caused an appreciable decrease, in shortening of germination period by 10 days. Results have shown that the soaking of chir-pine seeds in H2O2 (1% v/v) for 24 hours is highly beneficial and therefore for large scale germination, treatment of H2O2 should be preferred. The germination percentage of seeds was found to be positively correlated with altitude and negatively correlated with rainfall.

Keywords: Garhwal Himalaya, Provenance, Altitude, Hydrogen per oxide treatment, Seedling height

Abstract: The main sources of trace metals to plants are the air or soil media from which trace elements are taken up by the root or foliage. The air, soil and vegetable samples were collected from Industrial, Semi-urban and rural areas and were analysed for Pb, Zn, Ni and Cu. The rural area is free from contaminant sources and is treated as control. From each representative area composite samples of Tomato, Lady’s finger, Capsicum and leafy vegetable Bimli were collected and anlysed for Pb, Zn, Ni and Cu. The air environments in Industrial and Semi-Urban areas are enriched with the four trace metals, but the concentrations were within the permissible levels. This indicates that, despite the close proximity of the agricultural lands to high emitting industrial sources, soils do not seem to have been contaminated by atmospheric deposition. Remarkable differences were observed between the trace metal content in vegetables of rural areas with semi-urban and industrial areas. In industrial area Nickel, Zinc were reported in higher concentrations in tomato and capsicum where as in semi urban area the concentration of Cu is 2-3 times higher in tomato and lady’s finger on comparison with the rural vegetables. Based on the air accumulation factor and concentration factor calculations, the trace metals of Pb and Zn in industrial and semi-urban areas were found to be receiving the contributions from both atmospheric and soil inputs in all the four crops.

Keywords: trace metals, vegetables, air accumulation factor, concentration factor

Abstract: An experiment was laid down in the greenhouse to determine the distribution of weed seeds at different soil depths and period of cultivation on the distribution of weed seed bank in the soil profile in Muzarabani. Soil samples from different depth levels (0-10, 10.1-20, 20.1-30 cm) were collected soon after harvesting from three different sites namely Gutsa, Mufudzi and Muringazuva of Muzarabani district. The soil samples were put in trays in the greenhouse and watered after every two days to field capacity. Weed seedlings were identified, counted, recorded and discarded for a period of 3 months. Soil samples were disturbed every week to allow more germination of dormant weeds. Depth (P=0.000) and site (P=0.005) had highly significant effects on the total number of weeds that emerged from the soil samples. The 0-10 cm of the soil had the highest weed seedlings that emerged. There was an equal weed seed distribution in the 10-20 cm and the 20-30 cm of the soil. Gutsa had the largest seed bank and there was no significant difference in seed bank size between Mufudzi and Muringazuva. Some weed species were site specific, Senna obtusifolia was only found in Muringazuva and absent in other sites. Eleusine indica was found in Mufudzi and was absent in other sites.

Keywords: weed, soil, greenhouse, germination

Abstract: Picking a model for a problem is a major undertaking. If the model fits well then it can be used to increase understanding of the problem and/or for prediction. Several statistical procedures have been used by researchers for planting date studies to suit their objectives. The ever-proliferation of Statistical procedures available to researchers has given room for use of diverse statistical design for research into finding optimum planting time for crops. Considering the subtle differences, advantages and disadvantage that these statistical designs pose, the results of such analysis may lead to false conclusion or be less reliable at least for comparative purposes. There is need to look at date of planting trials again to see the possibility of proffering a statistical model that could be commonly used by researchers. The main purpose of this work is to apply the residual analysis to check the suitability of the series of similar experimental model to describe the effects of sowing dates on yield of upland rice with the view of predicting optimum sowing date. Results show that the series of similar experiment methodology is able to model the changes associated with different sowing dates. The questions associated with model adequacy were discussed.

Keywords: Sowing dates, rice, statistical model, residual analysis

Abstract: Variations in passerine populations were examined at a single Common Bird Census location over 24 years. Long term trends in the populations of Robin Erithacus rubecula, Blackbird Turdus merula, Wren Troglodytes troglodytes, Blue Tit Parus caeruleus and Great Tit Parus major were investigated. The statistical method proposed by Bulmer[1], which overcomes the problem of regressions to the mean, was used to investigate density-dependent variation (DDV). Little evidence of DDV was found and so long-term population trends could be evaluated. The commonest species seen were the Wren and Robin. Significant increases were seen in breeding pairs of Great Tit (p=0.001) and Wren (p=0.048) whereas those of Blackbird decreased (p=0.006) and there was no significant change in breeding pairs of Blue Tit (p=0.090) or Robin (p=0.871). Selection pressures on the populations studied were probably reduced by the consistently mild winters and feeding at bird tables in the gardens near the study area in winter. The CBC technique is recognised as the most accurate method of estimating the size of breeding bird populations. This analysis shows that the CBC data collection method, combined with relatively simple statistical techniques, can be used to accurately interpret local trends in breeding bird populations.

Keywords: Bird Census, density-dependent variation

Abstract: Knowledge on the expected effects of climate change on aquatic ecosystems is defined by three ways. On the one hand, long-term observation in the field serves as a basis for the possible changes; on the other hand, the experimental approach may bring valuable pieces of information to the research field. The expected effects of climate change cannot be studied by empirical approach; rather mathematical models are useful tools for this purpose. Within this study, the main findings of field observations and their implications for future were summarized; moreover, the modelling approaches were discussed in a more detailed way. Some models try to describe the variation of physical parameters in a given aquatic habitat, thus our knowledge on their biota is confined to the findings based on our present observations. Others are destined for answering special issues related to the given water body. Complex ecosystem models are the keys of our better understanding of the possible effects of climate change. Basically, these models were not created for testing the influence of global warming, rather focused on the description of a complex system (e. g. a lake) involving environmental variables, nutrients. However, such models are capable of studying climatic changes as well by taking into consideration a large set of environmental variables. Mostly, the outputs are consistent with the assumptions based on the findings in the field. Since synthetized models are rather difficult to handle and require quite large series of data, the authors proposed a more simple modelling approach, which is capable of examining the effects of global warming. This approach includes weather dependent simulation modelling of the seasonal dynamics of aquatic organisms within a simplified framework.

Keywords: ecological modelling, model system, community ecology, global warming, seasonal dynamics