Schiff bases have been synthesized by the reaction of p-nitrobenzaldehyde, o-nitrobenzaldehyde and p-toluyaldehyde with 4-amino-5-mercapto-1,2,4-triazole. The ligands react with Co(II), Ni(II) and Zn(II) metals to yield (1:1) and (1:2) [metal:ligand] complexes. Elemental analyses, IR, 1H NMR, electronic spectral data, magnetic susceptibility measurements, molar conductivity measurements and thermal studies have investigated the structure of the ligands and their metal complexes. The electronic spectral data suggests octahedral geometry for Co(II), Ni(II) and Zn(II). The antibacterial activities of the ligands and their metal complexes have been screened in vitro against three Gram-positive (Staphylococcus aureus, Staphylococcus epidermidis and Bacillus subtilis) and two Gram-negative (Salmonella typhi and Pseudomonas aeruginosa) organisms. The coordination of the metal ion had a pronounced effect on the microbial activities of the ligands and the metal complexes have higher antimicrobial effect than the free ligands.

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High temperature stress is major constraint to bread wheat (Triticum aestivum L. Em. Thell) production. Generation of information on the effect of high temperature stress on various traits may be helpful for developing thermotolerance bread wheat variety. An experiment was conducted on a set of 10 diverse genotypes, their 45 F1s and F2s for identification of high temperature stress genotype. The experiment was conducted under normal and late sown condition. The parent HD 2851, P8W 520, and HS 448, and the crosses HS 448 × PBW 520, UP 2614 × K 209 and PBW 520 × HD 2851 for grain yield per plant were least affected under late sown conditions. Heat stress intensity (Dvalue) clearly indicated that grain yield per pant biological yield per plant and grain yield per spike suffered revively under late sown conditions. Keywords: Bread wheat; heat susceptibility index; tolerant genotypes. DOI: http://dx.doi.org/10.3329/bjar.v36i3.9270 BJAR 2011; 36(3): 415-426

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Even though chickpea {Cicer arietinum L.) is well adapted to growing on stored soil moisture in drought-prone environments, drought is a major yield reducer in most chickpea-growing regions. Little progress has been made in breeding for improved performance under drought stress for want of a reliable and repeatable method of screening for drought resistance. Therefore, a study was initiated in 1990 to develop a screening technique and a rating scale to evaluate germplasm for drought resistance. A spring date-of-planting experiment was conducted during spring from 1990 to 1992 at Tel Hayda (northern Syria) to see if the expression of genotypic differences in drought resistance should be accentuated. Simultaneously, a rating scale was developed. Using the screening technique and rating scale, over 4000 germplasm lines were evaluated from 1992 to 1995. The resulting screening techniqtie involves delayed sowing by 3 weeks during spring at a relatively dry site (long-term average annual rainfall of 328 mm), preliminary evaltiation of materials on a rating scale of i-9 to discard susceptible lines, and final evaluation of promising lines under stress (drought) and non-stress (supplemental irrigation) conditions, selecting drought-resistant lines which perform well under both conditions. In the 1-9 rating scale that was developed: 1 = no yield reduction as compared to a non-stress control and 9 = al! plants dry without producing any seed. Using this technique, 19 lines out of 4165 lines screened were identified as drought resistant, producing over 1 t ha"' seed yield under drought conditions while being able to yield over 2 t b"' under nonstress conditions. Resistant lines are being used by national programs in the Mediterranean region and by ICARDA for developing drought-and disease-resistant. high-yielding cultivars.