Granular envelope research in Pakistan

In 1989, research on granular envelope design for subsurface horizontal pipe drains was started when existing design procedures for envelope design did not result in successful application of a granular envelope (crushed rock) material at the Fourth Drainage Project. Although construction problems were, in part, the reason for the failure of the crushed rock envelope, it was also found that standard design criteria need additional rules to prevent a similar occurrence of failure. Tests were performed in the laboratory with permeameters, sieves, and other equipment and preliminary results are reported. The effect of number, size and arrangement of perforations on the test results are indicated. Test results of blended granular materials such as crushed rock, river-run gravel and sand from various sources in Pakistan are outlined.Proceedings of 5th International Drainage Workshop, Lahore, Pakistan, ICID-CIID, IWASRI, 1992, Vol. III, 5.38–5.49.     

Evaluation of antioxidant activity of methanolic extract from peanut hulls in fried potato chips

Antioxidant activity of methanolic extract from peanut hulls (MEPH) was evaluated in fried potato chips during storage at 25 ^°C and 45 ^°C. Free fatty acids (FFA) and peroxide values (POV) were used as criteria to assess MEPH as an antioxidant. After six months storage at 45 ^°C potato chips treated with 1200 and 1600 ppm of MEPH showed lower values of FFA (0.083, 0.080%) and POV (30.0, 29.0 mEq/kg) than the control samples (FFA 0.377%, and POV 180 mEq/kg). Potato chips treated with BHA and BHT showed POVs of 29.0 and 25.0 mEq/kg whereas FFA values were 0.0086 and 0.074%, respectively, after six months storage at 45 ^°C. These results illustrate that MEPH, at various concentrations, exhibited very strong antioxidant activity which was almost equal to synthetic antioxidants (BHA & BHT). Subjective evaluation studies also showed that potato chips treated with 1200–1600 ppm MEPH after six months storage at 45 ^°C, were organoleptically acceptable.     

Metabolites of the fungistatic agent 2β-methoxyclovan-9α-ol by Macrophomina phaseolina

Biotransformation of 2β-methoxyclovan-9α-ol (1), a fungistatic agent against Botrytis cinerea, was investigated with Macrophomina phaseolina. Demethoxylation, regioselective oxidation at C-9 and C-13, and inversion of the configuration at C-9 of compound 1 afforded six oxidative metabolites, 2β-methoxyclovan-9-one (2), clovan-2β,9β-diol (3), clovan-2β,9α-diol (4), clovan-2β,13-diol-9-one (5), 2β-methoxyclovan-9α,13-diol (6), and clovan-2β,9β,13-triol (7). Compounds 5-7 are described here for the first time, and their structures were deduced by different spectroscopic techniques. The antifungal activity of new metabolites 5-7 was also evaluated against B. cinerea.     

Early urban development in the Near East

It has been thought that the first cities in the Near East were spatially extensive and grew outward from a core nucleated village while maintaining a more or less constant density in terms of persons or households per unit of area. The general applicability outside of the Near East of this southern Mesopotamian.derived model has been questioned recently, and variations from it are increasingly recognized. We can now demonstrate that such variation was present at the beginnings of urbanism in the Near East as well.     

IMPROVING SEED GERMINATION AND GREEN POD YIELD IN OKRA (HIBISCUS ESCULENTUS L.) USING CALCIUM CARBIDE—A NEW SOURCE OF ETHYLENE

The ability to sense and respond to physical stimuli is of key importance to all living things. Among the common environmental stimuli detected by living organisms are light, temperature, and a variety of chemical signals. A number of these stimuli appear to be closely related and can be considered as physico-mechanical stimuli. Plant hormones like ethylene have a definite role in plant growth stages from seed germination to senescence and death of plants. Calcium carbide, a solid material, has been proven in recent years to be a new source of this hormone. Calcium carbide absorbs moisture from soil and releases acetylene gas which by the microbial activities are converted to plant hormone ethylene. The role of calcium carbide was studied, especially the effects of this material during the seed germination stage. Under closed conditions this material was applied to okra seeds and its physico-chemical changes in seed during germination were observed. It was concluded from the experiment that calcium carbide has a definite role in okra seed germination as there was early germination and root formation observed in treated seeds with a callus formation on the roots of germinating seeds which developed in to secondary roots in very short time as compare to control in the same period. It was also observed that in treated okra plants, early flowering and fruit formation was initiated which contributed about 27% green pod yield increase in okra.     

Uncover the salt tolerance potential of accessions based on photosynthetic attributes and interaction plot in tomato (Solanum lycopersicum)

Soil salinity, being world's gravest and increasing environmental threat, limits the growth and development in nearly all crop plants. The experiment was laid out to investigate the tomato local and exotic germplasm for morpho‐physiological and photosynthetic attributes under salinity stress (0 (control), 8 and 12 dS m^?1). The phenotype data for morpho‐physiological traits were collected; meanwhile, photosynthetic pigments were analysed also at seedling stage. Analysis of variance, interaction plot, PCV and GCV revealed significantly greater diversity among all accessions for subjecting attributes. Strikingly, principle component analysis (PCA) biplot and cluster heatmap exposed potentially salt tolerant accessions (NAQEEB, BL1076, PBLA1401, 017859, TINY TIM, BL1174, BL1078, PBLA1932, TOMMY TOE, PAKIT and CLN2413) under the highest level of salinity for β‐carotene, lycopene contents, chlorophyll b, carotenoids, pheophytin (b) and total pheophytin. The overall performance of the above‐mentioned accessions was found significant and exhibits tolerant attitude under high salt levels. We suggest that these tolerant accessions might facilitate as a potential source for further breeding programme to improve the agronomically important traits by exploiting both conventional as well as molecular breeding efforts.     

Microsatellite marker-based identification of mother plants for the reliable propagation of olive (Olea europaea L.) cultivars in Australia

Summary

Olive production in Australia has continued to increase in recent years, however there remains a high degree of confusion on the genetic identities of the cultivars being grown. In the present study, seven microsatellite (simple sequence repeat; SSR) loci were used to identify a set of 53 olive tree samples from different sources. The microsatellite DNA profiles of all 53 tree samples, including seven unknown trees, were compared with the SSR profiles of 14 reference olive cultivars. A total of 60 fragments (alleles), averaging 8.57 alleles per microsatellite locus, were amplified. High average values were found for the observed heterozygosity, the expected heterozygosity, and the polymorphic information content (0.73, 0.74, and 0.72, respectively). While all seven microsatellite markers proved useful for characterisation and identification purposes, a combination of three SSR primer pairs (DCA9, DCA18, and EM030) was sufficient to distinguish all 53 olive samples. The microsatellite allelic profiles allowed the 53 tree samples to be grouped into 23 genotypes. The allelic profiles of 14 of these genotypes matched with their reference cultivars, while the genetic identities of the remaining nine genotypes could not be confirmed. Some of these unknown genotypes may have been derived from feral olive trees, or were due to mislabelling and/or planting errors among Australian olive cultivars. Our results confirm the usefulness of microsatellite markers as a tool for cultivar differentiation and identification, and indicate the need for reliable identification of mother plants for commercial propagation.     

Functional identification of G. hirsutum genes for their role in normal plant development and resistance against Verticillium dahliae using virus-induced gene silencing

European Journal of Plant Pathology - Virus-induced gene silencing (VIGS) is a reverse genetic tool used to identify the function of individual genes by reducing their expression. Here VIGS was...