Capital structure and debt maturity: Evidence from listed companies in Saudi arabia

This study examines the determinants of capital structure in general and the determinants of corporate debt- maturity in particular for 56 listed companies in Saudi Arabia. To achieve this objective the study was set to test a number of hypotheses regarding the determinants of capital structure and debt maturity. These hypotheses were related to the effects of profitability, growth opportunities, asset maturity, size, liquidity and age. Total debt ratio was found to be positively and significantly related to the percentage growth in total assets and negatively and significantly related to liquidity and asset structure. Growth opportunities variable was found to be positively and significantly related to long - term debt and was negatively and significantly related to short term debt. The relationship between asset maturity and long term debt was found to be negative and significant. Therefore, there is no support of the hypothesis that debt maturity decreases as the proportion of growth potentials increase. Size was found to be positively and significantly related to long term debt and negatively and significantly related to short term debt implying that larger firms borrow on long term and small ones borrow on short term. Profitability, age liquidity appeared to have no statistical significance on the different types of debt. The implications of these results have been examined and future research directions have been suggested

Comparative performance of two extractants in colorimetric determination of soil organic matter in paddy soil

Commonly used soil organic carbon (SOC) determination methods are expensive, time consuming, require equipment and skilled personnel making them impractical to use at field level. Therefore, a laboratory analytical study was carried out to identify a suitable extractant for SOC extraction as part of an ongoing effort to develop a low cost quick method for determining soil organic matter (SOM) at field level. For this purpose, 38 soil samples were collected from different Agro Ecological Zone (AEZ) to represent typical rice based cropping pattern covering a sufficient range in texture, soil organic matter, pH, and type of management. Two extractants e.g. NaOH-Pyrophosphate + HCl and NaOH-EDTA were used to extract organic carbon from soil and two wavelength e.g. 300 and 400 nm were used to measure the absorbance of organic carbon in spectrophotometer. Soil organic carbon measurements by CNS analyzer were used as reference measurement to compare the extracting efficiency of SOC by the selected extractants. Both the extract and wavelength showed different degrees of error in OC measurement. The error sum square of NaOH-Pyrophosphate + HCl and NaOH-EDTA measured at 300 nm wavelength were 15.21 and 13.35 whereas at 400 nm it was 227.37 and 19.95, respectively. Consequently, the average error percentages at 300 nm were -33 and -8 while at 400 nm it was - 187 and -16. Based on the error sum square and error percentage, NaOH-Pyrophosphate + HCl performed better than the NaOH-EDTA, and 400 nm wavelength came out better than the 300 nm wavelength. In addition, both the extracts produced coloured solutions which were easily visible or detectable by naked eye and the colour intensity increased with the increase in SOC content. Variations in colour among the soils depending on organic matter content indicate that it would be possible to develop a new low cost method for SOM determination at field level by using NaOH-Pyrophosphate + HCl as the extractant. Further research is warranted to confirm this finding

Evaluating manurial value of bioslurry for tomato cultivation in subtropical floodplain soil

Bioslurry is an anaerobically decomposed product, which comes out of the digester after extraction of biogas (chiefly CH4). Recently a huge amount of bioslurry is being produced in Bangladesh for enormous installation of biogas plants. Utilization of bioslurry is yet to be addressed adequately though it has potential value as a good quality organic fertilizer. Therefore, a field experiment supported by a laboratory analysis was conducted in floodplain soil of Bangladesh to evaluate the performance of bioslurry along with chemical fertilizers on the yield of tomato (Solanum lycopersicum). The experiment was laid out in a Randomized Complete Block Design (RCBD) with six treatments viz., Control (no fertilizer/manure), N200P90K180 (100% Recommended Fertilizer Dose, RFD), N120P54K108 (60% RFD) + Poultry manure (PM), N120P54K108 (60% RFD) + Poultry slurry, N120P54K108 (60% RFD) + Cowdung (CD), N120P54K108 (60% RFD) + Cowdung slurry, each treatment replicated thrice. Chemical analysis of cowdung, cowdung bioslurry, poultry manure and poultry bioslurry showed that the organic carbon, N, P, K and S varied from 10.1-35.1, 0.70-2.52, 0.18- 1.28, 0.86- 3.80 and 0.13- 0.61% respectively. Cowdung and poultry manure had the higher organic carbon content as well as higher nutrient concentration compared to cowdung bioslurry and poultry bioslurry. Nutrient concentration particularly N, P and S in cowdung and cowdung bioslurry was found lower than the poultry manure and poultry bioslurry. The fruit yield of tomato increased by 81-225% due to the application of different slurry, manure and chemical fertilizers compared to no application of manure or fertilizer (control). The highest fruit yield (27.2 t ha-1) of tomato was obtained from N120P54K108 + Poultry slurry treatment. Hence application of poultry bioslurry in combination with 60% recommended dose of fertilizers can help improve the production of tomato in sub-tropical floodplain soil

Development of in vitro propagation system for Atriplex halimus L.

Explants excised from adult shrubs were surface sterilized and cultured on Murashige and Skoog (MS) basal medium in thepresence of plant growth regulators (PGRs) at different concentrations. A high multiplication rate of 7.2-fold was achieved every four weekson MS medium supplemented with 4.44 μM BA, 0.49 μM IBA and 0.58 μM GA3. Rooting was achieved with 73% efficiency within 2-4 weekson agar-gelled MS basal medium free of PGRs. Rooted plantlets were gradually acclimatized to field conditions over 5-6 weeks with 65%efficiency. For in vitro selection for salt tolerance, MS medium was supplemented with increasing concentrations of NaCl ranging between25 and 1000 mM. This study has demonstrated that in vitro shoots could tolerate up to 600 mM NaCl with optimal growth at 200 mM, whilehigher concentrations of NaCl affected growth negatively. Growth and shoot number decreased with increasing NaCl concentration with allplantlets died at 1000 mM NaCl

Genetic engineering of apple (Malus domestica Borkh.) for resistance to fungal diseases using g2ps1 gene from Gerbera hybrida (Asteraceae)

In the present study, g2ps1 gene from Gerbera hybrida coding for 2-pyrone synthase which contribute for fungal and insectresistance was used. The aim was to work out an efficient approach of genetic transformation for apple cvs. ‘Golden Delicious’, ‘Royal Gala’and ‘MM111’, ‘M26’ rootstocks for improving their fungal resistance using genetic engineering techniques. Adventitious shoot formationfrom leaf pieces of apples studied was achieved using middle leaf segments taken from the youngest leaves from in vitro-grown plants.Optimum conditions for ‚direct’ shoot organogenesis resulted in high regeneration efficiency of 90%,95%,92%,94% in the studied applesrespectively. Putative transgenic shoots could be obtained on MS media with B5 Vitamins, 5.0 mg l-1 BAP, or 2.0 mg l-1 TDZ with 0.2 mg l-1NAA in the presence of the selection agent “PPT” at 3.0-5.0 mgl-1. Shoot multiplication of transgenic shoots was achieved on: MS + B5vitamins + 1.0 mg l-1 BAP + 0.3 mg l-1 IBA, 0.2 mg l-1 GA3+1.0 g/l MES+ 30 g/l sucrose + 7.0 g/l Agar, with the selection agent PPT at 5.0mg l-1 and were subcultured every 4 weeks in order to get sufficient material to confirm transformation of the putative shoots obtained. Six,seven, one and six transgenic clones of the apples studied respectively have been obtained and confirmed by selection on the media containingthe selection agent “PPT” and by PCR analysis using the suitable primers in all clones obtained for the presence of the selection” bar gene(447 bp) and the gene-of- interest “g2PS1” (1244 bp), with transformation efficiency of 0.4%, 0.6%, 0.1% and 0.3% respectively. Thesetransgenic clones were multiplied further in vitro in the presence of the selection agent ‘PPT’ and rooted in vitro. Rooted transgenic plantletswere successfully acclimatized and are being kept under-containment conditions according to the biosafety by-law in Syria to evaluate theirperformance for fungal resistance

Genetic engineering of apple (Malus domestica Borkh.) for resistance to fungal diseases using g2ps1 gene from Gerbera hybrida (Asteraceae)

In the present study, g2ps1 gene from Gerbera hybrida coding for 2-pyrone synthase which contribute for fungal and insect resistance was used. The aim was to work out an efficient approach of genetic transformation for apple cvs. ‘Golden Delicious’, ‘Royal Gala’ and ‘MM111’, ‘M26’ rootstocks for improving their fungal resistance using genetic engineering techniques. Adventitious shoot formation from leaf pieces of apples studied was achieved using middle leaf segments taken from the youngest leaves from in vitro-grown plants.Optimum conditions for ‚direct’ shoot organogenesis resulted in high regeneration efficiency of  0%, 95%, 92%, 94% in the studied apples respectively. Putative transgenic shoots could be obtained on MS media with B5 Vitamins, 5.0 mg l-1 BAP, or 2.0 mg l-1 TDZ with 0.2 mg l-1 NAA in the presence of the selection agent “PPT” at 3.0-5.0 mgl-1. Shoot multiplication of transgenic shoots was achieved on: MS + B5 vitamins + 1.0 mg l-1 BAP + 0.3 mg l-1 IBA, 0.2 mg l-1 GA3+1.0 g/l MES+ 30 g/l sucrose + 7.0 g/l Agar, with the selection agent PPT at 5.0 mg l-1 and were subcultured every 4 weeks in order to get sufficient material to confirm transformation of the putative shoots obtained. Six, seven, one and six transgenic clones of the apples studied respectively have been obtained and confirmed by selection on the media containing the selection agent “PPT” and by PCR analysis using the suitable primers in all clones obtained for the presence of the selection” bar gene (447 bp) and the gene-of- interest “g2PS1” (1244 bp), with transformation efficiency of 0.4%, 0.6%, 0.1% and 0.3% respectively. These transgenic clones were multiplied further in vitro in the presence of the selection agent ‘PPT’ and rooted in vitro. Rooted transgenic plantlets were successfully acclimatized and are being kept under-containment conditions according to the biosafety by-law in Syria to evaluate their performance for fungal resistance

Effect of long term fertilization on soil respiration and enzyme activities in floodplain soil

In agricultural farming system organic manuring and inorganic fertilizer application are the most common agricultural practices. Different fertilizer application lead to differences in soil nutrients, pH, and microbial species, which in turn affect the transformation and decomposition of organic carbon by soil microorganisms. Therefore, a laboratory incubation study was carried out to investigate the influence of long term manuring and fertilization on soil respiration by means of C mineralization and enzyme activities. A parallel first- and zero-order kinetic model was used to describe observed C mineralization in soil. The annual carbon mineralization was found to be significantly influenced by different fertilizer. This result indicates that more stable organic matter was formed in NP treated soil which is less prone to decomposition if present crop management has been changed. Other ward, NP has the highest potentiality to soil for the purpose of carbon sequestration in floodplain soil compared to other fertilizer. Urease activities varied from 4.7µg NH4-N/g soil/2h in NK treatment to 25.7µg NH4-N/g soil/2h in N+FYM treatment. N treatment had a significantly higher urease activity compared to the respective controls. When P, K, S and PK applied separately with N then the treatments show low enzyme activity to control and other treatments (N, N+FYM and NPKSZn). There were no significant differences for Arylamidase activities among the treatments. The arylamidase activities decreased when S applied in combination with N. On the other hand arylamidase activity increased with the application of all other treatment

Long - term fertilization effect of organic carbon and total nitrogen on floodplain soil

Soil organic matter is the most often reported indicator of soil quality and productivity and an evidence of previous soil management. Therefore, in 2017, a laboratory incubation study was carried out in the experimental filed of Bangladesh Institute of Nuclear Agriculture (BINA), Mymensingh, Bangladesh under control condition at 25°C for 104 days to investigate the influence of long term manuring and fertilization on soil respiration by means of C mineralization. Soil samples were collected from floodplain soil with rice-rice cropping pattern at Bangladesh Agricultural University (BAU) experimental farm having eight treatments. Long term (33 years) application of fertilizers and manure resulted in significant differences in soil organic carbon, total N content, and soil pH KCl between the treatments. The soil organic carbon and total N content varied among the different treatments from14.9 g OC kg-1 to 17.0 g OC kg-1 and1.60 g N kg-1 (control) to 1.78 g N kg-1 (application of NPK). The soil pH varied among the different treatments from 5.65(application of NK) to 4.89 (application of N). This result indicates that more stable organic carbon was formed in NPK treated soil which is less prone to de-composition if present crop management has been changed

Response of Potato to Ash as an Alternative Source of Potassic Fertilizer

An experiment was carried out during rabi season of 2011-2012 in the experimental field of Soil Science, Bangladesh Agricultural University (BAU), Mymensingh. The objectives of present research work was to evaluate ash as an alternative source of potassic fertilizer for potato cultivation. The treatment combinations were i) Control (No K), ii) 100% K of recommended dose from muriate of potash (MoP), iii) 75% K from MoP+ 25% K from ash, iv) 50% K from MoP + 50% K from ash, v) 25% K from MoP + 75% K from ash, and vi) 100% K from ash. The result of the experiment indicated that various combinations of ash and MoP influenced the yield, yield contributing characters (length of the tubers, breadth of the tubers, number of tubers per hill, weight of tubers per hill, weight of ten tubers and gross yield of tubers per plot), K content of po tato as well as weed infestation. Among the treatments the highest yield was obtained from 50% K from MoP + 50% from ash (T3) treated plot. The K content in the potato tuber and weed infestation was also highest for that plot. Considering the yield contributing parameters, yield and number of weeds the T3 (50% K from MoP + 50% K from ash) treatment was found more suitable than others