Oil biosynthesis and its related variables in developing seeds of mustard (<Emphasis Type="Italic">Brassica juncea</Emphasis> L.) as influenced by sulphur fertilization

The aim of this research was to study the effect of sulphur (S) fertilization on oil biosynthesis and its related variables at various stages of seed development, and to find possible explanations for increased oil content in the seeds of mustard (Brassica juncea L. Czern and Coss) due to S fertilization. Acetyl-CoA carboxylase activity and contents of oil, acetyl-CoA, soluble protein, total RNA, total sugar and sulphur were determined in the developing seeds of mustard grown in the field with sulphur (+S) and without sulphur (-S). The period between 10 to 30 days after flowering was observed as the active period of oil accumulation in the developing seeds of mustard. The accumulation of the oil was preceded by a marked rise in acetyl-CoA carboxylase activity and acetyl-CoA concentration, which declined rapidly when oil accumulation reached a plateau. Total sugar content decreased, while protein content increased during the active period of oil accumulation in the developing seeds (i.e. between 10–30 days after flowering). Sulphur fertilization significantly (P < 0.05) enhanced the oil accumulation in the developing seeds at all the growth stages. The increase in the oil content was 5–63% with S fertilization over the control treatment. Acetyl-CoA carboxylase activity and contents of acetyl-CoA, soluble protein, total RNA and sugar were significantly (P < 0.05) higher in the developing seeds of +S-treated plants compared to — S-treated plants. It is suggested that the increase in the oil content with sulphur fertilization may be associated with the increases in acetyl-CoA carboxylase activity through the enhancement of acetyl-CoA concentration. Further, the increased sugar content due to S fertilization provided enough carbon source and energy for oil biosynthesis.     

Improvement of nitrogen management in rice paddy fields using chlorophyll meter (SPAD)

Optimum rate and timing application of nitrogen (N) fertilizer are most crucial in achieving high yield in irrigated lowland rice. In order to assess leaf N status, a semidwarf rice cultivar (Khazar) was grown with different N application treatments (0, 40, 80, and 120 kg N ha⁻¹ splited at transplanting, midtillering, and panicle initiation stages) in a sandy soil in Guilan Province, Iran, in 2003. The chlorophyll meter (SPAD 502) readings were recorded and leaf N concentrations were measured on the uppermost fully expanded leaf in rice plants at 10-day internals from 19 days after transplanting to grain maturity. Regression analysis showed that the SPAD readings predicted only 23% of changes in the leaf N concentration based on pooled data of leaf dry weight (N _dw) for all growth stages. However, adjusting the SPAD readings for specific leaf weight (SPAD/SLW) improved the estimation of N _dw, up to 88%. Specific leaf weight (SLW), SPAD readings, leaf area and weight as independent variables in a multiple regression analysis predicted 96% of the N _dw changes, while SPAD readings independently predicted about 80% of leaf N concentration changes on the basis of leaf area (N _a). It seems that chlorophyll meter provides a simple, rapid, and nondestructive method to estimate the leaf N concentration based on leaf area, and could be reliably exploited to predict the exact N fertilizer topdressing in rice.     

Population dynamics of citrus leaf miner on different varieties of citrus in correlation with abiotic environmental factors in Sargodha District,Punjab, Pakistan

From January 2010 to December 2011, samples of leaves from citrus varieties Kinnow, Musambi and Feutral were taken from the five tehsils (administrative subdivisions) of Sargodha District in Pakistan including Sargodha, Bahalwal, Silanwalli, Sahiwal and Kotmomin, to study the population trends in citrus leaf miner (CLM), Phyllocnistis citrella (Stainton) (Lepidoptera: Gracillariidae), and its correlation with various environmental factors: (temperature, humidity and rainfall); plant morphological factors: moisture contents of leaves, leaf thickness, surface area (cm ² ), and biochemical percentage of calcium, potassium and magnesium in leaves. The maximum population of CLM was observed on Kinnow and Feutral, followed by Musambi. The effect of these factors on the larval population was 8.39- 2.30(Mg)+2.73(K)-0.398(Ca)-0.100(Temp)0.038(Humidity)+0.567(Rain)+0.07(Moist) 1.01 (Thickness)-0.022(Surface area). This equation revealed that magnesium, calcium, temperature, humidity, leaf thickness and leaf surface area are negatively correlated with larvae population, whereas potassium, rainfall and moisture are positively correlated with larvae population.     

Amylose contents of cereals; influence of household processing on the amylose contents of these foods

Amylose is a food starch found in cereals, legumes and root vegetables. Keeping in view the importance of amylose for various food industries as well as its importance on domestic level, the current study was conducted to analyze the amylose content of common cereals e. g rice （sela, coarse and basmati）, maize yellow, Kisan and Azam varieties and wheat （Tatara, Fakhr-e-sarhad and Bakhtawar-92） varieties as well as quantifying the influence of cooking/boiling procedures on the amylose contents of cereals. The maximum amylose content were observed for wheat variety Tatara （24.28%） followed by Bakhtawar-92 （22.74%） and Fakhr-e-sarhad （19.77%）. Among maize and rice varieties studied, Kisan and course rice were rich in amylose content with values of 27.19 and 30.48% respectively. The chapti of Tatra wheat were scored highest for appearance （7.6）, flavor （7.5）, texture （7.6） and overall acceptability （7.55）. The roti of Kisan and Azam varieties got maximum appearance score of 7.6 as compared to 7.4 for maize yellow variety. Basmati rice was scored highest regarding appearance （8.4）, flavor （8.6）, texture （8.6） and overall acceptability （8.53. The moisture content ranged from 10.61 （Azam） to 8.01% （wheat variety Fakhr-e-sarhad）. Cooking reduced the amylose content of wheat bread from （19.77%-24.28%） to （15.47%-15.94%） with cooking time of 5 min, maize bread from （21.48%-27.19%） to （19.53 %-25.85%） with maximum cooking time of 10 min and boiled rice from （24.90%-30.48%） to （24.18%-30.19%） with cooking time ranging from 12 to 20 min. It can be inferred from these studies that the reduction in amylose content were more in chapti/roti preparation of wheat and maize varieties as compared to boiling of rice varieties and that significant varietals differences exist in amylose content of the uncooked samples.     

Temperature and pH effects on biodegradation of hexachlorocyclohexane isomers in water and a soil slurry

This study was conducted to monitor the biodegradation of alpha-, beta-, gamma-, and delta-hexachlorocyclohexane (HCH) isomers in liquid culture by a Pandoraea species and determine the influence of pH and temperature on the biodegradation of alpha- and gamma-HCH in liquid as well as in soil slurry cultures. The Pandoraea species degraded 79.4% delta-HCH and 34.3% gamma-HCH in liquid culture at 4 weeks of incubation. alpha- and beta-HCH exhibited almost identical rates (41.6 and 42.4%, respectively) of degradation. The highest degradation of alpha- and gamma-HCH (67.1 and 60.2%, respectively) was observed at an initial pH of 8.0 in liquid; 58.4 and 51.7% rates of degradation of alpha- and gamma-HCH, respectively, at an initial pH of 9.0 were found in soil slurry cultures. An incubation temperature of 30 degrees C was optimum for effective degradation of alpha- and gamma-HCH isomers (62.5 and 57.7%, respectively) in liquid culture, and 54.3 and 51.9% rates of degradation of alpha- and gamma-HCH isomers, respectively, were found in a soil slurry. Increasing the soil/water ratio decreased the extent of degradation of both HCH isomers. Degradation of HCH isomers occurred concomitant with bacterial growth. Byproducts of growth from Pandoraea species significantly decreased the pH of the liquid and the soil slurry during the growth on HCH isomers. The results of this study suggest that this bacterial strain may effectively be used for remediating polluted sites and water contaminated with different HCH isomers over a range of environmental conditions.     

Improving nodulation,growth and yield of Cicer arietinum L. through bacterial ACC-deaminase induced changes in root architecture

Bacteria containing ACC-deaminase in the vicinity of roots may influence plant growth by modifying root architecture through their potential to regulate ethylene synthesis in plant roots. Approximately 138 isolates capable of utilizing ACC as the sole source of N were isolated from the rhizosphere soil of chickpea (Cicer arietinum L.) plants. Under axenic conditions, some rhizobacterial isolates were highly effective in increasing root length (up to 2.08 fold), number (up to 3.7 fold) and length (up to 3.9 fold) of lateral roots, and root biomass (up to 83%) of chickpea as compared to uninoculated control. Serratia proteamaculans strain J119 was found to be the most effective plant growth promoting rhizobacterium (PGPR) in improving root and shoot growth, nodulation and grain yield of chickpea as compared to respective controls in growth pouches, pot and field trials. A highly significant direct correlation (r = 0.99) was observed between number of lateral roots under axenic conditions (jar trial) and number of nodules per plant in pot and field trials. Interestingly, S. proteamaculans J119 also exhibited highest ACC-deaminase activity in addition to root colonization compared to other tested strains. The results of this study demonstrated that changes in root growth and architecture (particularly lateral roots) as a result of inoculation with PGPR containing ACC-deaminase are crucial for improving growth, yield and nodulation of chickpea under field conditions.     

In vitro callogenesis and detection of somaclonal variations in Plantago ovata L.

Planago ovata L. is an economically important species in the monotypic genus Plantago. It is a short-stemmed annual herb. The seed husk of this plant is commonly called psyllium or isabgol which is important in pharmaceutical formulation and food industry. In this study, callus induction was optimized using different explants of Plantago ovata. Callus DNA was utilized to access the somaclonal variations using the Random Amplification of Polymorphic DNA (RAPD) markers. The maximum callus growth was observed in Murashige and Skoog (MS) medium containing 4 mg L^?1 2,4-D concentration for shoots, 0.5 mg L^?1 for seeds and 2 mg L^?1 for roots. Moreover, the effect of culture age was considered in assessing genetic variability. Maximum genetic variability was observed in the DNA samples of callus at the concentration of 2 mg L^?1 2,4-D for all explants (roots, shoots, and seeds). Cluster analysis was performed based on 1) similarity coefficient between samples and 2) molecular data using the Numerical Taxonomy and Multivariate Analysis System (NTSYS) PC version 2.01; similarity index was generated by similarity for Quantitative Data (SIMQUAL). Our study indicated that Random Amplified Polymorphic DNAs can successfully be used to explore polymorphism among callus samples at different hormonal concentrations. This study can be useful for the production of callus from Plantago ovata and estimation of genetic variations due to tissue culture conditions. Evaluation of genetic variations can display novel features and manipulate genetic bottlenecks in Plantago ovata. New genetic variations in somaclones can bring vital insight for plant improvement.