Muhammad Aslam Khan

Immobilization of Rose Waste Biomass for Uptake of Pb(II) from Aqueous Solutions

Rosa centifolia and Rosa gruss an teplitz distillation waste biomass was immobilized using sodium alginate for Pb(II) uptake from aqueous solutions under varied experimental conditions. The maximum Pb(II) adsorption occurred at pH 5. Immobilized rose waste biomasses were modified physically and chemically to enhance Pb(II) removal. The Langmuir sorption isotherm and pseudo-second-order kinetic models fitted well to the adsorption data of Pb(II) by immobilized Rosa centifolia and Rosa gruss an teplitz. The adsorbed metal is recovered by treating immobilized biomass with different chemical reagents (H2SO4, HCl and H3PO4) and maximum Pb(II) recovered when treated with sulphuric acid (95.67%). The presence of cometals Na, Ca(II), Al(III), Cr(III), Cr(VI), and Cu(II), reduced Pb(II) adsorption on Rosa centifolia and Rosa gruss an teplitz waste biomass. It can be concluded from the results of the present study that rose waste can be effectively used for the uptake of Pb(II) from aqueous streams.

Microsatellite Analysis of Rosa damascena from Pakistan and Iran

For the perfume industry, Rosa damascena is the most important species used in the production of rose attar which is made by distilling volatile oils from the petals of flowers. It is also used widely in the manufacture of rose water, as a flavoring agent. Other species like Rosa gallica L., Rosa centifolia L., Rosa × borboniana Desp. and the rose cultivar Gruss an Teplitz also exhibit the fragrance that is sought by perfumeries in the world. The main rose oil producers in the world are Turkey and Bulgaria, and they are obtaining the rose oil almost exclusively from the single clone of R. damascena. In the recent studies a wide genetic diversity for R. damascena has been revealed in Iran, but there was a need to explore and evaluate the R. damascena in the neighboring areas of Iran. Thus the new research project was planned with the objective to evaluate the genetic diversity amongst R. damascena landraces grown in Pakistan and the subsequent comparison with tested germplasm grown in Iran. Further, the study is based on the collection of Damask and selected garden roses from Pakistan, Iran and USA, determining the characterization through microsatellite markers. The SSR markers confirmed the high level of diversity of the Rosa damascena germplasm within Iran and showed that the Pakistani genotypes were similar to those from the Iranian provinces of Isfahan, Kerman and Fars. The garden rose cultivars were distantly related.

Prediction of Potato Late Blight Disease Based upon Environmental Factors in Faisalabad, Pakistan

Potato late blight (PLB) caused by Phytophthora infestans (Mont.) de Bary, is an important and serious threat to successful potato production in the world. It spreads through seed and soil residual material. In Pakistan, PLB disease can induce 100% yield losses under epidemic condition. Due to lack of resistance in indigenous potato germplasm, disease is managed through fungicides by the growers of Pakistan. Excessive use of fungicides causes resistance in the pathogen and creates fatalistic effect on the environment. Disease predictive model under such situation may be effective tool to predict early onset of disease. A disease predictive model was developed on two years data of PLB disease severity and epidemiological factors using stepwise regression analysis. Model explained upto 80% disease variability. Maximum and Minimum temperature, relative humidity, rainfall and wind speed appeared to be most significant factors in the PLB disease development. The environmental conditions conducive for the development of PLB disease were characterized. Maximum and minimum temperatures in the range of 16-20°C and 1-6°C were found favourable for potato blight disease. Similarly, relative humidity, rainfall and wind speed in the range of 63-71%, 1.5-3.75 mm and 1-5.5 Km/h, respectively, were conducive for PLB disease which are helpful in disease development.

Monitoring of rust virulence pattern through avirulence/virulence formula

The idea of this study was to be vigilant with rust virulence pattern changes in the region and to organise wheat breeding and variety release programmes in the light of findings of rust virulence patterns. The survey was carried out during March–April (2010 and 2011) on the rust trap nurseries planted at different Agra-ecological condition in Pakistan. The rust trap nursery consisted of 40 Lr differentials and 24 Yr differentials and data were recorded following modified Cobb’s scale. The studies revealed that there were no virulence for Lr9, Lr19, Lr23+, Lr25, Lr28, Lr27+31 Lr32, Lr34, Lr36 and Lr37 and Yr3, Yr5, YR8, Yr10, Yr15, Yr18, and Yrsp observed during this period. Among the varieties Iqbal-2000, Uqab-2000, Lasani-2008, Faisalabad-2008, AARI-2011, Millat-2011 and Pb-2011 exhibited resistance path for LR and YR. Moderate YR was observed on Shafaq-2006 & Chenab-2000 ranging from 20–30 M RMS. In these studies the susceptible check variety Morocco was almost 80–100S for LR and YR.

Pathogenic aspects of Pantoea agglomerans in relation to cotton boll age and Dysdercus cingulatus (Fabricius) transmitting seed and boll rot in cotton germplasm

Bacterial seed and boll rot is a newly emerging cotton disease in Pakistan. Twenty-one cotton varieties were screened to find resistance source against the disease. None of these was found to be resistant. Five cotton varieties (CIM-595, MK2, BT-986, BT-986 & SG-1) having 700–1400 Area under disease progress curve (AUDPC) units were found to be moderately resistant to the disease. SLH-317, FH-942, BT-222, BT-666, MNH-457 ranging from 1401–1700 AUDPC units were moderately susceptible while MNH-456, SLH-336, 9811, FH-942, MNH-886 susceptible to boll rot. Seven varieties (FH-114, FH-113, BT-7, BT-212, SLH-BT-4, BT-212 and FH-941) were highly susceptible to bacterial seed and boll rot indicated by 2001–2300 AUDPC units. Biochemical tests identified bacterial isolates as Pantoea agglomerans. Different inoculation techniques were assessed for bacterial pathogenicity and symptoms of boll rot were only observed in needle punctured bolls. One, two and three weeks old bolls were mechanically inoculated by injecting bacterial suspension to evaluate the boll’s age impact on disease severity. Maximum severity was observed in two weeks old bolls. Red cotton bugs (Dysdercus cingulatus) were fed on artificially inoculated diseased bolls and then transferred on healthy bolls. Diseased symptoms were noticed on healthy cotton bolls. Bacterial colonies were recovered and red cotton bug was confirmed as the disease-transmitting vector.

Symptomatic expression of tristeza-infected citrus plants in Pakistan

Variable symptoms were recorded during a survey in the citrus trees infected or suspected to be infected with citrus tristeza virus based on ELISA tests. Sweet orange manifested main symptoms like bud union crease, pin holing, bark cracking, incompatibility, yellowing and dropping of leaves. Pin holing was particularly prevalent in Sweet orange (Citrus sinensis Osbeck), Kinnow (Citrus reticulata Blanco) and Grapefruit (Citrus paradisii Mcaf.), while incompatibility was only in Sweet orange and Grapefruit.

EXPLORING THE POTENTIAL OF MULTIVARIATE ANALYSIS TO STUDY THE IMPACT OF COTTON LEAF CURL DISEASE ON YIELD TRAITS

Cotton production in Pakistan seems adequate, but inclined to several biotic and abiotic constraints, especially Cotton Leaf Curl Virus posing a hazardous impact on cotton yield by affecting yield traits, fiber quality and health status of plants. In this study, eight Bt and four Non-Bt cotton genotypes were sown under augmented design in the experimental area of the Department of Plant Pathology, University of Agriculture, Faisalabad. Presence of virus was confirmed by using the graft inoculation technique in greenhouse while natural inoculum was also relied upon for infection under field conditions. Data encompassing plant height, number of bolls, 50 % open bolls, boll weight, number of sympodial and monopodial branches were collected after disease appearance and subjected to multivariate analyses of variance which revealed that all genotypes responded distinctly to Cotton Leaf Curl Disease. Then these data were subjected to linear discriminant analysis where first two linear discriminants explained 61.05% and 23.54% variability respectively, and highlighted plant height and 50% open bolls as maximum variability explaining cotton yield traits in response to disease. Territorial map was constructed between first two linear discriminants which revealed that disease influenced plant height and 50% open bolls of Bt cotton genotypes potentially than the Non-Bt genotypes. Moreover, data for plant height and 50% open bolls were split and subjected to Hypothesis-error (HE) plot which depicted negative correlation between plant height and 50% open bolls and described the results in conformation with territorial map. Hence, these tools can be potentially used to study the impact of disease on crop yield traits and for selection of lines/varieties either for future breeding program or farmer field.

Epidemiological Studies of Tomato Leaf Curl Virus Disease Based upon Environmental Variables

Tomato leaf curl virus (TLCV) is an emerging problem in tomato growing areas of Pakistan. Relationship of TLCV disease and environmental conditions were studied on five tomato cultivars. Temperature (maximum and minimum) and relative humidity significantly contributed in the development of TLCV disease during two years (2012 and 2013). The TLCV disease incidence increased with rise in maximum and minimum temperature and decreased with the increase in relative humidity. The contribution of maximum temperature was explained by linear regression which showed 83 to 91% variability in the disease incidence and minimum temperature explained 75 to 85% variability. Relative humidity exerted 78 to 85% contribution in the disease development. The linear regression could not explain the contribution of rainfall and wind speed in disease development. The characterization of favorable environmental conditions for TLCV disease development would contribute towards accurate prediction and timely management of the disease.

Development of predictive model based on epidemiological factors for the management of potato late blight disease.

Potato late blight (PLB) caused by Phytophthora infestans (Mont.) de Bary, is an important and serious threat to successful potato production in the world. It spreads through seed and soil residual material. In Pakistan, PLB disease may cause complete crop failure under severe epidemic conditions. Due to lack of resistance in indigenous potato germplasm, disease is managed through fungicides by the growers of Pakistan. Nonetheless, excessive use of fungicides cause resistance in the pathogen and create fatalistic effect on the environment. Disease predictive model under such situation may be effective tool to predict early onset of disease which is helpful to reduce number of sprays. The data of five susceptible to highly susceptible varieties sown for consecutively ten years were collected from Plant Pathology Section, Ayub Agricultural Research Institute (AARI), Faisalabad. A disease predictive model was developed based on ten years data of PLB severity and epidemiological variables using stepwise regression analysis. The model was validated by regression model based on two years data. The results revealed that the ten years model explained 74%, while two years model explained 80% disease variability. In accordance of variety wise models, SH-5 and Diamont models explained up to 91% and 89% disease variability, respectively during two year. The predictive model was used for the management of PLB disease and only three sprays were applied. Applied sprays reduced the PLB disease severity on all the five varieties (N-22, FD48-4, FD69-1, FSD White and Cardinal) up to 2.46, 6.50, 2.50, 8.46 and 1.67%, respectively. All the treatments significantly reduced the disease severity whereas Phenylamide and Propineb were the most effective as compared to the control. Prediction of disease model would be helpful to apply two or three sprays of fungicides (Phenylamide and Propineb) to control late blight of potato successfully.

Impact of global warming on insects

Climate change is the most debated issue of time-posing hazardous impacts on life on earth. Like other living entities, insects are also influenced by rising temperatures, elevated carbon dioxide (CO2) and fluctuating precipitating patterns as range expansion, increased epizootics (insect outbreaks) and new species introduction in regions where previously these were not reported. Increasing temperature and elevated CO2 have substantial impacts on plant–insect interaction and integrated pest management programmes. Rising temperature leading to rapid development of insects and increasing the epizootics of harmful insects is a precarious threat not only to agroforestry but to urban extents as well. By employing the proactive and modern scientific management strategies like monitoring, modelling prediction, planning, risk rating, genetic diversity and breeding for resistance, the suspicions innate to climate change effects on can be diminished.