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Background: The seroprevalence and risk factors of bovine brucellosis were studied at animal and herd level using a combination of culture, serological and molecular methods. The study was conducted in 253 randomly selected cattle herds of the Potohar plateau, Pakistan from which a total of 2709 serum (1462 cattle and 1247 buffaloes) and 2330 milk (1168 cattle and 1162 buffaloes) samples were collected. Data on risk factors associated with seroprevalence of brucellosis were collected through interviews using questionnaires. Univariable and multivariable random effects logistic regression models were used for identifying important risk factors at animal and herd levels. Results: One hundred and seventy (6.3%) samples and 47 (18.6%) herds were seropositive for brucellosis by Rose Bengal Plate test. Variations in seroprevalence were observed across the different sampling sites. At animal level, sex, species and stock replacement were found to be potential risk factors for brucellosis. At herd level, herd size (≥9 animals) and insemination method used were important risk factors. The presence of Brucella DNA was confirmed with a real-time polymerase chain reaction assay (qRT-PCR) in 52.4% out of 170 serological positive samples. In total, 156 (6.7%) milk samples were positive by milk ring test. B. abortus biovar 1 was cultured from 5 positive milk samples. Conclusion: This study shows that the seroprevalence of bovine brucellosis is high in some regions in Pakistan. Prevalence was associated with herd size, abortion history, insemination methods used, age, sex and stock replacement methods. The infected animal may act as source of infection for other animals and for humans. The development of control strategies for bovine brucellosis through implementation of continuous surveillance and education programs in Pakistan is warranted. [ABSTRACT FROM AUTHOR]

Present study was carried out at Cotton Research Institute, AARI, Faisalabad, Pakistan during 2012 to find out genetic components viz., heritability, genetic advance and correlation among various yield traits of twenty cotton genotypes grown in RCBD. It was concluded that the boll size of FH-207 (1) and FH-207 (22) was large, tapering shape, good opening and leaf was of medium size as compared to all other varieties. It was concluded that higher values of heritability and genetic advance were recorded for first bud days (99.40%, 173.67%), sympodial branches (87.98%, 108.42%), monopodial branches (35.24%. 51.42%), number of bolls per plant (99.76%, 348.18%), plant height (99.91%, 256.09%), boll weight (94.65, 37.25%), GOT percent (88.06%, 69.76%) and fibre strength (98.53%, 61.61%) respectively. Significant correlations were found for boll weight, number of bolls, staple length, fibre strength and fibre fineness. Higher heritability, genetic advance and significant genotypic and phenotypic correlations suggested that selection may be useful for enhancement of cotton yield and quality. [ABSTRACT FROM AUTHOR]

In Pakistan during last two decades the major factor limiting cotton production is cotton leaf curl virus disease (CLCuD). For estimation of genetic diversity regarding CLCuD tolerance, fiber quality and some yield contributing traits, 101 cotton genotypes imported from USA were evaluated. Different statistical procedures like cluster, principle components (PC) and correlation analysis were employed to identify the suitable genotypes that can be further exploited in breeding programme. Significant associations were found between yield contributing trait, boll weight and fiber related trait, staple length. Earliness related traits, like days taken to 1st square and days taken to 1st flower had positive correlation with each other and both these traits also showed their positive association with ginning out turn. The negative significant correlation of CLCuD was obtained with monopodial branches, sympodial branches and plant height. Principal component (PC) analysis showed first five PCs having eigen value >1 explaining 67.8% of the total variation with days to 1st square and flowering along with plant height and sympodia plant-1 which were being the most important characters in PC1. Cluster analysis classified 101 accessions into five divergent groups. The genotypes in cluster 1 only showed reasonable values for days to 1st square and flower, sympodia per plant, ginning out turn, staple length and fiber fineness and the genotypes in cluster 5 showed promising values for the traits like cotton leaf curl virus, ginning out turn and fiber fineness. The genotypes in cluster 1 and 5 may be combined to obtain desirable traits related to earliness and better disease tolerance. Scatter plot and tree diagrams demonstrated sufficient diversity among the cotton accessions for various traits and some extent of association between various clusters. It is concluded that diversity among the genotypes could be utilized for the development of CLCuD resistant lines with increased seed cotton and lint yields with desirable fiber quality. [ABSTRACT FROM AUTHOR]

The variation in Bt toxin was measured in three cotton genotypes (MNH-886, FH-142 and FH-Lalazar) at Agricultural Biotechnology Research Institute, AARI, Faisalabad, Cotton Research Station, Sahiwal, Cotton Research Station, Vehari, Pakistan during 2012. The varieties were measured in seed, 20 days old leaf, peduncle of 20 days old leaf, anther, stigma, pedicel, ovary, petals and& bracts, immature stem, mature stem, 15 days old boll, 30 days old boll, fully matured boll, main roots, secondary roots and all leaves from top to downwards position. Seed hasmaximumMaximum Bt toxin protein was measured in seed 14.9 (μg/g fresh weight) followed by leaves (5.18 μg/g) irrespective ofto location and genetic background. All the floral parts including anthers, stigma, pedicel, ovary and petals contained varying magnitude of Bt toxin. No Bt toxin was detected in mature stem, 15 days old boll, 30 days old boll, fully matured boll, main roots and secondary roots. FH-142 had maximum Cry1Ac protein followed by MNH-886 and FH-Lallazar. The expression of Bt toxin was higher at Sahiwal followed by Faisalabad and Vehari. The top most leaf of stem contained maximum amount of Bt toxin in all types of genotypes at all and locations. The Bt toxin gradually decreased in leaves from top to downwards and uptoup to 8th position leaf, it remaineds 2.28 μg/g on fresh weight basis which is sufficient for the control of lepidopteron insects. [ABSTRACT FROM AUTHOR]

Eight promising genotypes were crossed in all possible combinations using 8x8 diallel system for combining ability analysis. Data was recorded for seed yield and some important yield attributes. The results for combining ability analysis indicated significant general combining ability for most of the traits except plant height and siliqua length. UCD-8/4, KJ-119 and BRS-2 were good general combiners for yield related traits. A cross BRS-2 x UCD-8/4 showed best desired SCA for number of primary branches and siliquae per plant. S-9 x Canola Raya for siliqua length, Canola Raya x UCD-8/4 for number of seeds per siliqua, KJ- 119 x BRS-2, BARD-1 x NIFA Raya for 1000-seed weight while cross BRS-2 x UCD-8/4 for seed yield showed good positive SCA, involving at least one of the promising general combiner parents. It was suggested that selection should be delayed up to sixth segregating generation for number of primary branches, number of siliqua per plant, siliqua length and seed yield due to highly significant genotypic mean square and pre-dominant role of non- additive type of gene action while for number of seeds per siliqua and seed weight, selection in early generations would be suitable due to prominance of additive gene action. [ABSTRACT FROM AUTHOR]

Barani Agricultural Research Institute (BARI), Chakwal has a strong breeding programme for oilseed research including Brassica crops. Long and consistent breeding efforts on Brassica improvement programme by the breeders has resulted in the development of a high yielding and drought tolerant elite line SPS-5, selected from the segregating progenies of a cross between Ganyou-4 x Westar. Breeding was carried out by the pedigree method and the elite line was evaluated for its yield potential in various yield trials conducted at BARI, Chakwal from 1994 to 1998. Based on the desirable phenotypic traits and superior seed yield, SPS-5 was approved as a rapeseed variety "Chakwal Sarson" by the Punjab Seed Council in 2002 for general cultivation in the Punjab barani tract. [ABSTRACT FROM AUTHOR]

The present study was carried out at Cotton Research Station, Ayub Agricultural Research Institute, Faisalabad, Pakistan during 2019 to estimate the genetic variation in 6 genotypes of cotton at three different sowing dates regarding cotton leaf curl disease (CLCuD) tolerance, quality and yield traits. For this purpose ANOVA, correlation and principal component analysis were performed. The ANOVA showed that sowing date effects were significant for sympodial branches count while varietal effects were significant for all studied traits i.e. sympodial branches count, height of plant, bolls count, fiber length, fiber fineness, whitefly population, cotton leaf curl disease (CLCuD), yield except days to first boll open and ginning out turn GOT(%). The interaction of sowing date and variety was significant only for plant height. The analysis of correlation depicted that days to 1st boll open had significant negative correlation with sympodial branches count, bolls count, GOT(%), fiber length and yield while it had positive correlation with CLCuD. However, GOT(%) and fiber length had positive correlation with yield. Whitefly has positive correlation with CLCuD and CLCuD had negative correlation with yield. In principal component (PC) analysis out of 13 PCs, first three contributed 69.4(%) towards variability. PC I was important as yield had maximum negative factor loading and CLCuD % has maximum positive factor loading in PC I. Further, there was important contribution of plant height, bolls count and sympodial branches count in PC I. Inshort, days to first boll opening shows positive correlation with CLCuD, so early planitng should be preferred to get optimum yield. [ABSTRACT FROM AUTHOR]

Cotton crop in Pakistan has faced many threats including CLCuV disease, late sowing risks, low yield and poor quality of fiber. Thirty three genotypes from F4 were assessed for earliness, CLCuV disease tolerance, high yield and good quality of fiber at Cotton Research Station, AARI, Faisalabad, Pakistan during 2018-19. For evaluation of these genotypes Principal Component analysis (PCA) and cluster analysis were performed to select suitable genetic material to utilize them in further breeding programs. The Principal Component Analysis showed first six Principal components having eigen value >1 showing 81. 6 % of total variation with bolls count, weight of bolls, sympodial branches count and yield as being most related to PC I. Cluster Analysis divided 33 genotypes into four divergent groups. Cluster 2 showed least value for CLCuV %, Cluster 3 showed good values for bolls characters, fiber quality and yield and cluster 4 showed good values for earliness. The genotypes in cluster 2, 3 and 4 can be combined to get desired traits combination. The biplot and the dendrogram highlighted significant variation in studied cotton cultivars for different traits and it is assessed that the variation in these genotypes can be exploited to develop early, CLCuV disease resistant lines along with the increased seed cotton yield having good fiber quality. [ABSTRACT FROM AUTHOR]

An experiment was conducted to study the inheritance pattern of earliness in cotton at experimental area of Department of Plant Breeding and Genetics, University of Agriculture, Faisalabad, Pakistan during 2010-11. For this purpose a 5×5 diallel mating system was employed in F2 generation of cotton to study the inheritance pattern of earliness and yield related traits. Analysis of variance revealed significant variation (P<0.01) for all the traits studied. The regression coefficient deviated significantly from zero but not from unity for all the traits. The additive component (D) was significant for all the traits but less than the values of dominance components H1 and H2 for days to squaring (H125.40, H222.01), days to flowering (H132.64, H231.39), days to boll opening (H134.88, H226.64), maturity of bolls (H121.35, H220.90), node number for 1st sympodial branch (H14.27, H24.04) and seed cotton yield (H1242.32, H2230.27) showing the preponderance of non-additive genetic effects. Estimates of narrow senses heritability were high for sympodial branches (70%), moderate for days to squaring (50%), node number to 1st sympodial branch (45%) and earliness index (50%). Predominance of additive genetic effects in sympodial and monopodial branches along with seed cotton yield per plant is indicative of early generation selection. [ABSTRACT FROM AUTHOR]

A study was carried out at Cotton Research Institute, AARI, Faisalabad Pakistan during the year 2013 to determine the cause and effect of some morphological traits viz. number of leaves per plant, number of sympodial branches per plant, number of bolls per plant and plant height on seed yield per plant in upland cotton. Seventy two cotton genotypes at F5 generation were sown in a RCBD with three replications. The results indicated that number of leaves (0.2334), sympodial branches (0.4859) and number of bolls per plant (0.3722) had exerted positive and significant to highly significant correlation at genotypic level with seed cotton yield per plant. The data also revealed that number of leaves showed positive and highly significant correlation with sympodial branches (0.3427"") plant height (0.6924"") and bolls per plant (0.4238""). Number of leaves, bolls per plant and sympodial branches showed positive direct effect on seed-cotton yield per plant. Direct effect of sympodial branches on cotton yield was very high and positive. However, number of leaves showed positive indirect effect via sympodial branches, bolls per plant and plant height. Similarly sympodial branches had shown positive indirect effect on seed yield per plant via number of leaves and bolls per plant. Direct effect of number of leaves on seed-cotton yield per plant was low while indirect effect via number of bolls per plant was positive. The number of bolls per plant also showed positive indirect effect via number of leaves, sympodial branches and plant height but effect of plant height on cotton yield was negative via number of bolls and sympodial branches. The results conclude that sympodial branches per plant influenced the cotton yield per plant to greater extent. Hence selection based on this trait may lead to development of genotypes having high seed cotton yield potential. [ABSTRACT FROM AUTHOR]

Abstract: Lahore, Pakistan is an emerging megacity that is heavily polluted with high levels of particle air pollution. In this study, respirable particulate matter (PM2.5 and PM10) were collected every sixth day in Lahore from 12 January 2007 to 19 January 2008. Ambient aerosol was characterized using well-established chemical methods for mass, organic carbon (OC), elemental carbon (EC), ionic species (sulfate, nitrate, chloride, ammonium, sodium, calcium, and potassium), and organic species. The annual average concentration (±one standard deviation) of PM2.5 was 194 ± 94 μg m−3 and PM10 was 336 ± 135 μg m−3. Coarse aerosol (PM10−2.5) was dominated by crustal sources like dust (74 ± 16%, annual average ± one standard deviation), whereas fine particles were dominated by carbonaceous aerosol (organic matter and elemental carbon, 61 ± 17%). Organic tracer species were used to identify sources of PM2.5 OC and chemical mass balance (CMB) modeling was used to estimate relative source contributions. On an annual basis, non-catalyzed motor vehicles accounted for more than half of primary OC (53 ± 19%). Lesser sources included biomass burning (10 ± 5%) and the combined source of diesel engines and residual fuel oil combustion (6 ± 2%). Secondary organic aerosol (SOA) was an important contributor to ambient OC, particularly during the winter when secondary processing of aerosol species during fog episodes was expected. Coal combustion alone contributed a small percentage of organic aerosol (1.9 ± 0.3%), but showed strong linear correlation with unidentified sources of OC that contributed more significantly (27 ± 16%). Brick kilns, where coal and other low quality fuels are burned together, are suggested as the most probable origins of unapportioned OC. The chemical profiling of emissions from brick kilns and other sources unique to Lahore would contribute to a better understanding of OC sources in this megacity. [Copyright &y& Elsevier]