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Long-term impact of buctril super (bromoxynil) herbicide in the wheat fields on soil microbial population, nitrate-N, Olsen-P, total organic carbon (TOC) and enzyme activities was evaluated in 18 sites in Pakistan. Nine sites were randomly selected from those places where bromoxynil herbicide had been used for the last 10 years designated as soil ‘X’ and other nine where no herbicide was used in that period designated as soil ‘Y’. Very importantly, it was found that long-term application of this herbicide in wheat fields reduced the actinomycetes and fungi population up to 19.7 and 14.3%, respectively, urease and dehydrogenase activity by 17.5 and 28.2%, respectively, and reduced nitrate-N, Olsen-P and TOC up to 55, 17 and 28.57%, respectively. Presence of high clay and organic matter contents enhanced the detrimental effect of herbicide by prolonging its persistence as compared to light-textured soils with low organic matter. As in Pakistan this herbicide is being used most frequently in wheat fields, da...

Reduced early crop growth and limited branching are amongst yield limiting factors of linola. Field response of seed priming treatments viz. 50 mmol L−1 salicylic acid (SA), 2.2% CaCl2 and 3.3% moringa leaf extract (MLE) including untreated dry and hydropriming controls was evaluated on early crop growth and yield performance of linola. Osmopriming with CaCl2 reduced emergence time and produced the highest seedling fresh and dry weights including Chl. a contents. Osmopriming with CaCl2 reduced crop branching and flowering and maturity times and had the maximum plant height, number of branches, tillers, pods and seeds per pod followed by MLE. Increase in seed weight, biological and seed yields was 9.30, 34.16 and 39.49%, harvest index (4.12%) and oil contents (13.39%) for CaCl2 osmopriming. Positive relationship between emergence and seedling vigor traits, 100-seed weight, seed yield with maturity time, 100-seed weight and seed yield were found. The study concludes that seed osmopriming with CaCl2 or MLE can play significant role to improve early crop growth and seed yields of linola.

Silicon (Si) distribution and accumulation in plant organs is widely reported as beneficial to overcome biotic and abiotic stresses. The investigation on distribution of Si in plant organs under water stress conditions was studied through experiments conducted at Arid Agriculture University, Pakistan during 2007–2009. Treatments (Si200: 200 ml l−1 of potassium silicate and Si0: control or absence of silicon) were replicated thrice with two sorghum cultivars; SPV462 (drought susceptible) and Johar-1 (drought tolerant) screened using osmotic media of PEG-6000 (−4.0, −6.0, −8.0 and −10.0 MPa). The results exhibited increased leaf water potential, leaf area index, SPAD chlorophyll with increased silicon concentration in leaves and roots of drought-tolerant genotype as compared to SPV462. Johar-1 exhibited maximum values for net assimilation and relative growth rate under silicon treatment in comparison to silicon absence. Similarly, maintenance of transpiration rate, because of accumulation of silicon in leaves resulted in optimum leaf water potential and optimum growth of crop.

The present investigation on Brassica juncea L. genotypes is an attempt to study variations and to generate variability through hybridization and also to obtain genetic information on some yield attributes for selection in segregating generations. Eight promising genotypes were selected and crossed in all possible combinations under complete diallel system. Data was recorded for seed yield and some important yield attributes. Analysis of variance showed significant differences for all the traits and therefore further analyzed using Hayman’s approach, which showed existence of both additive and dominance gene effects governing all the traits. However, estimates for genetic components of variation revealed that additive effects were more important for seeds per siliqua and 1000-seed weight indicating possibility of selection for these traits in early segregating generations. Dominance effects were more prominent with presence of over-dominance for plant height, number of primary branches per plant, number of siliqua per plant, siliqua length and seed yield per plot, thus suggesting that selection could be effective in latter generations. Only siliqua length showed the presence of directional dominance, while asymmetrical distribution of dominant genes among the parents was identified for all the traits. Key words: Indian mustard, genetic analysis, gene action, yield attributes, complete diallel.

In this study, biodiesel is prepared from Sinapis alba L. oil commonly known as white mustard through transesterification of the crude oil with methanol in the presence of NaOH as catalyst. Optimum conditions for the reaction were established to achieve maximum biodiesel yield of 92% at 6:1 molar ratio (methanol to oil), by using 0.5 g of NaOH, reaction temperature 65°C, and reaction time 75 minutes. Sinapis alba oil biodiesel (SAOB) was testified by using various fuel properties such as kinematic viscosity at 40°C (5.45 cSt), density at 15°C (0.8721 kg/L), acid number (0.242 mg KOH/gm), flash point (90°C), cloud point (−10°C), pour point (−13°C), and sulfur contents (0.00432%). Based on these findings, it is stated that SAOB can be used as alternative fuel in diesel engines.

Dengue virus (DENV) belonging to the family Flaviviridae consists of 4 serotypes (DEN-1, 2, 3 & 4) causing severe illnesses like dengue fever (DF), Dengue Hemorrhagic Fever (DHF) and Dengue Shock Syndrome (DSS). Dengue fever has become an emerging disease in Pakistan during the past 5-7 years with an increase in the number of cases every year since 2006. The current study aimed at identifying the serotypes of dengue virus involved in 2011 outbreak of Pakistan. Samples were collected from all provinces of Pakistan. Patients were confirmed in the hospital by antibody captured Enzyme linked immunosorbent assay (ELISA). These ELISA positive serum samples were inoculated on HeLa cell line to raise the viral titer of dengue virus and then RT-PCR was done for serotyping of dengue virus. Initially D1, D2 primers were tried for serotyping of dengue virus but poor results were obtained. Then serotype specific primers were designed having equal fragment length targeting NS1 gene. This approach was successful in serotyping of dengue virus from Pakistani population. On Real time RT-PCR, Dengue virus (DENV) was detected in 43.33% (n=26) patientsout of 60 analyzed samples. Among 26 positive cases, 76.9% (n=20) were children and 23.1% (n=6) were adultsand 46.1% (n=12) were male and 53.8 % (n=14) were females. ELISA results of26 PCR positive cases show that 53.8% (n=14) were positive for IgM, 15.4 % (n=4) were positive for IgG and 30.8 % (n=8) were positive for both IgG and IgM. In this study DEN-2 was detected in 13.3% (n=8) patients, DEN-3 was detected in 16.67% (n=10) patients and DEN-2 & DEN-3 coinfection was detected in 13.3% (n=8) patients. We did not detected DEN-1 & DEN-4 in 2011 outbreak of Pakistan in 60 analyzed samples. By this study we can conclude that DEN-2 and DEN-3 were the main serotypes involved in 2011 outbreaks in Pakistan.

Dengue virus infections are a major cause of mortality and morbidity in Southeast Asia South and Central America with rsquo deaths annually Two factors are accountable for the severe outcomes of Dengue Hemorrhagic Fever DHF one is the virulence of the virus and second is the cross reactivity of various dengue serotypes with the immune system of the host Rapid rise in the levels of various cytokines particularly Tumor Necrosis Factor alpha TNF alpha Interleukin IL Interleukin IL Interleukin IL have a major role in inducing distinctive clinical presentations of DHF These range from simple plasma leakage to hemorrhagic problems and even shock Another hallmark of DHF is the presence of cross reactive primary antibodies which produce an intense immune response in secondary infection resulting in immune mediated pathology seen in DHF There have been many attempts made in the past for the development of a suitable vaccine for dengue fever Vaccination using plasmid DNA against dengue fever is an active area of research In this review the role of different cells in the multiplication of dengue virus and viral interactions with the immune system have been discussed Special emphasis is given to the nature of DNA vaccines in general developmental efforts of a dengue fever vaccine

Field experiments were conducted at two different locations (Barani Agriculture Research Institute Chakwal and farmer's field in Talagang) in northern rainfed Punjab, Pakistan, to assess relative efficiency of two sources of sulfur (S) in enhancing nitrogen (N) fixation and yield of chickpea (Cicer arietinum L.). The treatments were four combinations of two levels of S (15 and 30 kg ha−1) from two sources [gypsum and ammonium sulfate (AS)] and a no-S control. Application of S significantly increased seed yield up to 12% and 14% at Chakwal and Talagang, respectively. Response (kg seed yield kg−1 S) at economic optimum dose (EOD) was greater for AS than for gypsum. Sulfur application enhanced the S uptake at both locations significantly. Sulfur harvest index and S economic yield efficiency ratio were greater at Talagang than at Chakwal. Sulfur application resulted increases in N uptake by 19% and 20% and N fixation by up to 19% and 30% at Chakwal and Talagang, respectively. Ammonium sulfate was more effecti...

Prevailing temperature at anthesis influences pollen health, fertilisation, seed filling, oil and fatty acid accumulation in different circles of sunflower head. Field experiments were conducted, during 2007 and 2008, at Pir Mehr Ali Shah, Arid Agriculture University, Rawalpindi, Pakistan, to document oil and fatty acid distributions in different circles of sunflower head. Hybrid S-278 was planted in randomised complete block design with a two factors factorial experiment, with four replications. At maturity, heads were divided into three equal circles (outer, middle and central); thereafter, oil and fatty acid distributions were separately determined in each circle. Oil and fatty acid concentrations in three circles differed significantly. The outer circle accumulated high oil and oleic contents which decreased to a minimum in the central circle; however, linoleic acid consistently increased, from outer to central circle, during both the years.

The effect of photothermal quotient at anthesis and maturity on kernel m -2 , kernel weight (KW) and kernel yield were examined in experiments involving three different genotypes such as: Chakwal-50, Wafaq-2001 and GA-2002 sown at five different sowing times (Planting windows) for two years (2008-09 and 2009-10) at the National Agricultural Research Center (NARC) Islamabad. Photothermal quotient (PTQ) was calculated at anthesis (PTQ1) and maturity (PTQ2) for two years. A direct relationship was observed between photothermal quotients, kernel m -2 , kernel weight and kernel yield for all planting windows and genotypes. The maximum value (213.15) of photothermal quotient was recorded when crop was grown on 28th Oct, 2008 (PW2) during the first year and minimum value was observed (143.82) for PW5 (25th Dec, 2009) during the second year. Decrease in photothermal quotient was observed from PW2 to PW5, whereas correlation analysis depicted positive and significant association with individual kernel weight, kernel m- 2 and kernel yield with PTQ. The correlation coefficient (r) between kernel m- 2 and PTQ1 was 0.5103, while the correlation between PTQ2, individual kernel weight (0.6375) and yield (0.6507) exhibited significance. The outcomes of photothermal quotient and the relationship established through these experiments between kernel m- 2 , KW and kernel yield and PTQ may be used as a road map to minimize yield losses and select genotypes and managements according to availability of climatic resources. Keywords : Wheat, photothermal quotient, kernel weight, solar radiation, environment

Iron (Fe) deficiency is one of the major yield-limiting factors in peanut (Arachis hypogaea L.), especially when grown in calcareous soils. The soils of the Pothwar region in Pakistan are calcareous in nature, exposing peanut to Fe deficiency. The molecular mechanisms governing Fe deficiency response in peanut have not been fully revealed. We compared 4 locally important varieties of peanut to evaluate Fe deficiency responses at the molecular level. The expression profiles of 7 important genes including AhIRT1, AhFRO1, AhNRAMP1, AhYSL1, AhYSL3.1, AhYSL4, and AhYSL6 in roots and young and old leaves of local peanut varieties were investigated 19 days after Fe deficiency treatment. Significant differences were observed for gene expression patterns among these varieties. The expression of AhIRT1 was upregulated only in Banki and BARD-699. However, some of the genes, like AhFRO1, AhNRAMP1, and other genes of the YSL family, were upregulated in BARI 2000 roots and young and old leaves, which has been reported for uptake and transport of Fe. BARI 2000 and Chakori had more accumulation of Fe in young leaves and roots in Fe deficiency conditions as compared to other varieties. This suggests that other mechanisms of Fe uptake and transport may be more important than AhIRT1 to mitigate Fe deficiency in BARI 2000 and Chakori.

SUMMARY Wide adaptability of sunflower and wide range of climatic conditions existing in Pakistan make it possible to have two crops of sunflower in a year, i.e., in spring and fall. Field experiments, one in spring and another in fall were conducted at the University of Arid Agriculture, Rawalpindi, Pakistan, to evaluate the influence of seasonal variations on yield and yield components of sunflower. Five sunflower hybrids were planted in a randomized complete block design in three replications. Two inner rows were harvested for measurements of yield and yield components. It was observed that head size of spring crop was larger than fall crop. Contrary to head size, 1000-seed weight of the fall crop was larger than that of the spring crop. However, final yield of the spring crop was greater than that of the fall crop. It led to the conclusion that having spring crop is the best option, while fall crop could be supplementary one, to increase the production of oilseeds.

Field experiments have been conducted to quantify the growth and development of sunflower in response to seasonal variation over two seasons, i.e., Spring and Fall. Five sunflower hybrids were sown in a randomized complete block design. Growth and development parameters like stem girth, plant height and dry matter accumulation m⁻² were recorded at the time of maturity. The hybrid Suncross-42 produced the maximum stem girth in Spring which was significantly different from that of XF-263 which was the lowest in both seasons. Plant height followed a pattern similar to stem girth. The hybrid Suncross- 42 produced the tallest plants in both seasons. Stem girth and plant height are considered major contributors to total dry matter production. Dry matter accumulation m⁻² followed a pattern similar to those of stem girth and plant height. The hybrid Suncross-42 produced the maximum dry matter in both seasons. Similarly, it produced maximum seed yields in both seasons. Overall superiority of the Spring crop over the Fall crop, in terms of stem girth, plant height, dry matter and seed yield production, may be related to the duration of crop in the field and environmental factors prevailing during the crop life cycle.

The unpredictability and large fluctuation of the climatic conditions in rainfed regions do affect spring wheat yield and grain quality. These variations offer the opportunity for the production of better quality wheat. The effect of variable years, locations and sowing managements on wheat grain yield and quality was studied through field experiments using three genotypes, three locations for two years under rainfed conditions. The two studied years as contrasting years at three locations and sowing dates depicted variability in temperature and water stress during grain filling which resulted considerable change in grain yield and quality. Delayed sowing, years (2009–10) and location (Talagang) with high temperature and water stress resulted increased proline, and grain quality traits i.e. grain protein (GP) and grain ash (GA) than optimum conditions (during 2008–09, at Islamabad and early sowing). However, opposite trend was observed for dry gluten (DG), sodium dodecyl sulphate (SDS), SPAD content and grain yield irrespective of genotypes. The influence of variable climatic conditions was dominant in determining the quality traits and inverse relationship was observed among some quality traits and grain yield. It may be concluded that by selecting suitable locations and different sowing managements for subjecting the crop to desirable environmental conditions (temperature and water) quality traits of wheat crop could be modified.

This study investigated lytic enzyme activities in three indigenous Trichoderma strains namely, Trichoderma asperellum, Trichoderma harzianum and Trichoderma sp. Native Trichoderma strains and a virulent strain of Rhizoctonia solani isolated from infected bean plants were also included in the study. Enzyme activities were determined by measuring sugar reduction by dinitrosalicylic acid (DNS) method using suitable substrates. The antagonists were cultured in minimal salt medium with the following modifications: medium A (1 g of glucose), medium B (0.5 g of glucose + 0.5 g of deactivated R. solani mycelia), medium C (1.0 g of deactivated respective antagonist mycelium) and medium D (1 g of deactivated R. solani mycelia). T asperellum showed presence of higher amounts of chitinases, β-1, 3-glucanases and xylanases in extracellular protein extracts from medium D as compared to medium A. While, the higher activities of glucosidases and endoglucanses were shown in medium D extracts by T. harzianum. β-glucosidase activities were lower compared with other enzymes; however, activities of the extracts of medium D were significantly different. T. asperellum exhibited maximum inhibition (97.7%). On the other hand, Trichoderma sp. did not show any effect on mycelia growth of R. solani on crude extract.

A 72-day greenhouse pot experiment was conducted with a sandy loam or a silt loam soil to examine the effects of farmyard manure (FYM), poultry litter (PL) and biogenic waste compost (BWC) at 10 g dw kg-1 soil on microbial biomass and activity and growth and nutrient uptake by wheat. Soil samples were collected at days 0, 14, 28, 42, 56 and 72 after planting. Growth and nutrient uptake by wheat were determined on day 72. All three amendments increased microbial biomass C, N and P, dehydrogenase activity, plant growth and nutrient uptake with a greater effect by FYM and PL than by BWC. All amendments increased microbial biomass C, N and P and enzyme activity particularly on day 0. These microbial parameters decreased after day 0 indicating microbial biomass turnover. All amendments increased plant growth and nutrient uptake. It is concluded that organicamendments can stimulate microbial growth and nutrient uptake as well as plant growth and nutrient uptake. Microbes can increase plant nutrient availability by nutrient mobilisation but also because nutrients taken up by the microbial biomass initially could become available to plants when the microbial biomass turns over as the easily available C is depleted.

The effect of variability in temperature, solar radiation and photothermal quotient were studied under varying planting windows in three wheat genotypes to cope environmental vulnerability. Regression models are regarded as valuable tools for the evaluation of temperature, solar radiation and photothermal quotient effects on wheat yield to bring its resilience to climatic vulnerability. The objective of this study was to evaluate sole and cumulative impact of temperature and solar radiation on spring wheat ( Triticum aestivum L.) yield using regression modeling approach. The data collected at maturity for grain number, grain weight and grain yield were regressed against mean temperature, solar radiation and photothermal quotient (PTQ) (temperature plus solar radiation) from emergence to anthesis and maturity, using STATISTICA9 software. Scatter-plot regression model was developed at 95% confidence interval with crop data and climate variables. Results indicate direct relationship of yield with solar radiation, cumulative effect of temperature and solar radiation, whereas yield had an inverse relationship with temperature alone. Direct relationship between PTQ and yield parameters confirmed PTQ as crop-yield determinant, thus, its management needs to be done by choosing a more appropriate sowing time and best suited genotypes as an adapted management strategy for farmers under increased climatic vulnerability. Key words: Photothermal quotient, planting windows, solar radiation, temperature, wheat.

A 72-day greenhouse pot experiment was conducted with a sandy loam or a silt loam soil to examine the effects of farmyard manure (FYM), poultry litter (PL) and biogenic waste compost (BWC) at 10 g dw kg-1 soil on microbial biomass and activity and growth and nutrient uptake by wheat. Soil samples were collected at days 0, 14, 28, 42, 56 and 72 after planting. Growth and nutrient uptake by wheat were determined on day 72. All three amendments increased microbial biomass C, N and P, dehydrogenase activity, plant growth and nutrient uptake with a greater effect by FYM and PL than by BWC. All amendments increased microbial biomass C, N and P and enzyme activity particularly on day 0. These microbial parameters decreased after day 0 indicating microbial biomass turnover. All amendments increased plant growth and nutrient uptake. It is concluded that organicamendments can stimulate microbial growth and nutrient uptake as well as plant growth and nutrient uptake. Microbes can increase plant nutrient availability by nutrient mobilisation but also because nutrients taken up by the microbial biomass initially could become available to plants when the microbial biomass turns over as the easily available C is depleted.

Water stress and high temperature variability are the major constraints for wheat crop productivity and food security in the context of climate change. Impact of high temperature and water stress at anthesis stage of spring wheat was studied through field experiments conducted during 2008 to 2009 and 2009 to 2010. Five wheat varieties of diverse origin namely Tatara, National Agricultural Research Centre (NARC)-2009, Sehar-2006, SKD-1 and F-Sarhad were sown in randomized complete block design (RCBD) replicated four times. Physiological parameters that is, net photosynthesis (An), transpiration rate (E), SPAD chlorophyll contents and prolines were recorded at anthesis stage. The results indicated reduction of An and increased E due to high temperature and moisture stresses. Among genotypes, maximum photosynthetic rate was recorded for Tatara (30.52 μ mole/m2/s) followed by NARC-2009. The E recorded maximum in Sehar-2006 (2.80 mole/m2/s) which had low photosynthetic activity whereas minimum E observed in Tatara (2.27 μ mole/m2/s) followed by NARC-2009. Maximum SPAD value observed in Tatara (53.17) followed by NARC-2009 (49.00) where as Sehar-2006 (37.17) depicted less chlorophyll contents and ultimately reduced photosynthesis and productivity. The highest proline contents were recorded in Tatara (59.69 µg g-1) followed by NARC-2009 (55.05 µg g-1) as compared to SKD-1 (46.27 µg g-1) and F-Sarhad (50.58) which might be due to genetic potential and physiological adaptability of Tatara cultivars against stress conditions. Water stress and high temperature at anthesis led to reduction in photosynthesis resulting reduced biomass and limited yield. Therefore, genotypes having better physiological performance under biotic stresses need to be considered for cultivation under changing environment. Since Tatara performed best in our study, it is recommended for cultivation under high temperature and moisture stresses. The values of all physiological attributes (An and E) were higher during first year (2008 to 2009) as compared to second year (2009 to 2010) which was due to relatively high temperature and low moisture availability during the second year. Key words: Temperature, water stress, photosynthesis, transpiration, proline, SPAD chlorophyll, anthesis, wheat.