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The objective of the present investigation was to study the chemical composition of stem of Pongamia pinnata is a species of tree native to India growing in semi-arid region of Kachchh district, Gujarat, India. The stem of Pongamia pinnata were subjected to Energy Dispersive X-ray Fluorescence (EDXRF) and were analyzed for different mineral composition. As the X-ray Fluorescence is one of the most reliable and accurate, as well as it is also a consistent and nondestructive method for analysis of major and trace elements using a single pressed pellet. During the study it was found that Potassium, Chloride, Calcium, Silicon, Sulfur, Aluminum, Phosphorus were noted in higher amounts, compared to that of other elements like Manganese, Iron, Nickel, Copper, Zink, Bromide, Rubidium, Strontium, Stannous, whereas the elements which were not detected in stem of Pongamia pinnata are Titanium, Cobalt, Hafnium and Tantalum.
Spatial variability of salinity and alkalinity is important for site-specific management since they are the most important factors influencing soil quality and agricultural production. Geostatistical methods provide a means to study the heterogeneous nature of spatial distributions of soil salinity and alkalinity. The present study was carried out to evaluate the accuracy of different spatial interpolation methods including kriging, cokriging and IDW methods for prediction of spatial distribution of salinity (EC) and sodium adsorption ratio (SAR) in soils of Ziaran region in Qazvin province, Iran. The tracking of the soil profi les was done using a Garmin eTrex-H model global positioning system (GPS) receiver. Sampling was done with stratifi ed random method and sixty soil samples from 0 to 15 cm depth were collected. After data normalization, the variograms were developed. For selecting the best model for competing on experimental variograms, the lower RSS value was used. Experimental variograms were fitted to spherical and exponential models. The best model for interpretative was selected by means of cross validation and error evaluation methods, such as RMSE method. The sum of Ca2++ Mg2+ and Na+ concentration which were highly correlated with soil salinity and sodium adsorption ratio, respectively, are used as auxiliary parameters in this study. The results showed that kriging and cokriging methods were better than IDW method for prediction of EC and SAR. Finally, the soil EC and SAR maps were prepared, using different spatial interpolation methods in GIS environment.
Tomato though a day neutral crop, is predominantly cultivated during the cool dry harmattan partly due to low incidence of diseases and favourable low temperature. The scarcity of fresh tomato outside this season needs to be considered to meet the teeming demand of the populace. Knowledge of the nature of association between yield and its components is of great necessary in any breeding programme. It was against this background that a field experiment was conducted in 2008 and 2009 at Salam Farm of Ngaburari village of Konduga Local Government Area of Borno State (Lat. 12°N and Long. 13°13’E) in the Semi-Arid Region of Nigeria to determine the relationship between yield and other agronomic parameters as affected by mulching and cultivars of tomato (Lycopersicon lycopersicum L. Karst) during the heat period to provide effective tool for breeders. The treatments consisted of five cultivars of tomato (Tandino, Danbaga, Roma VF, UC82B and Dansyria) and six grass mulch (Pennisetum pedicelatum Trin) levels (0 t/ha, 2.5 t/ha, 5 t/ha, 7.5 t/ha, 10 t/ha and 12.5 t/ha) which were laid out in a strip-plot design and replicated three times. The parameters studied include plant height, number of leaves, leaf area, leaf area index, number of branches per plant, days to first and 50 % flowering, number of fruits, weight of fruits per plant and yield in t/ha. Data collected were subjected to Correlation Analysis using Statistic 8.0 and the results of the combined years for cultivars indicated that total fruits yield was significantly and positively correlated with plant height, number of leaves, leaf area, leaf area index, days to first flowering and weight of fruits but significantly negatively correlated with days to 50 % flowering. Similarly, correlation of parameters as affected by mulch indicated significant and positive correlation of fruit yield with plant height, number of leaves, leaf area, leaf area index days to first flowering, number of fruits and weight of fruits but significantly negatively correlated with number of branches and days to 50 % flowering. Days to first flowering had significant positive correlation with days to 50 % flowering, number of fruits and weight of fruits both as affected by cultivar and mulch. Hence selection for high yield during heat period in the semi arid region of Nigeria should be based on earliness to flowering.
An experimental study on Carica papaya leaves was carried out in Thermo gravimetric analyzer (TGA), Differential Thermal Analyzer (DTA) and Differential Scanning Calorimetric (DSC) analyzer to investigate the effects of reaction atmosphere on thermal chemical characteristics. Experimental results show that In DSC curve, Endothermic peak at 101 °C is attributed to dehydration/Water loss from surface and pores of the powder sample. Step at 215 °C is associated with second order phase transition such as Glass Transition and it should be further confirmed in second heating (During heat- cool- heat cycle). Endothermic peak at 336 °C is associated protease thermal decomposition /Beta Cyclodextrin breakdown. In the TGA Curve, The initial 4 % weight loss is due to water loss from surface/pores of powder sample. Second weight loss between 200-450 °C is associated to degradation of cellulose and hemicellulose.
Water shortage is a major problem that limits growth and productivity of plants in arid and semi-arid regions. Protecting plants from adverse environmental conditions by using simple methods could be of great value under these conditions. In the present study, we examined water status and drought tolerance of snap bean, a drought-sensitive plant, and Jerusalem artichoke, a relatively drought tolerant plant in response to the application of salicylic acid (SA). Different levels of SA were applied and several physiological, growth, productivity and quality parameters were recorded together with the relative water content. Foliar application of SA improved growth, productivity, quality as well as some physiological parameters of snap bean and Jerusalem artichoke plants exposed to drought stress. Total chlorophyll content and relative water content were higher in plants treated with SA compared to control plants when subjected to drought stress. The specific responses of snap bean and Jerusalem artichoke to SA under drought stress as well as the possible explanations of the effects of SA are discussed.
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