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Highly ordered mesoporous γ-Al 2 O 3 particles and MgO materials were synthesized by evaporation induced self-assembly (EISA) and template-free hydrothermal co-precipitation routes, respectively. Ni, Ni–MgO, and Ni–La 2 O 3 -containing catalysts were prepared using a wet-impregnation method. The synthesized catalysts were characterized by N 2 adsorption–desorption, XRD, SEM-EDS, DRIFTS, XPS, TGA-DTA, and Raman spectroscopy analysis. The mesoporous γ-Al 2 O 3 catalyst support exhibited a high surface area of 245 m2/g and average pore volume of 0.481 cm3/g. The DRIFTS results indicate the existence of large Lewis's acid regions in the pure γ-Al 2 O 3 and metal-containing catalysts. Catalytic activity tests of pure materials and metal-containing catalysts were carried out at the reaction temperature of 750 °C and a feed molar ratio of AA/H 2 O/Ar:1/2.5/2 over 3 h. Complete conversion of acetic acid and 81.75% hydrogen selectivity were obtained over the catalyst 5Ni@γ-Al 2 O 3. The temperature and feed molar ratio had a noticeable impact on H 2 selectivity and acetic acid conversion. Increasing the water proportion in the feed composition from 2.5 to 10 considerably improved the catalytic activity by increasing hydrogen selectivity from 81.75% to 91%. Although the Ni-based γ-Al 2 O 3 -supported catalysts exhibited higher activity performance compared to the Ni-based MgO-supported catalysts, they were not as resistant to coke formation as were MgO-supported catalysts. The introduction of MgO and La 2 O 3 into the Ni@γ-Al 2 O 3 and Ni@MgO catalysts' structures played a significant role in lowering the carbon formation (from 37.15% to 17.6%–12.44% and 12.17%, respectively) and improving the thermal stability of the catalysts by decreasing the agglomeration of acidic sites and reinforcing the adsorption of CO 2 on the catalysts' surfaces. Therefore, coke deposition was reduced, and catalyst lifetime was improved. • γ-Al 2 O 3 -supported catalysts were active and selective towards H 2 production. • Ni-containing MgO-supported catalysts were stable and resistant to coke deposition. • The catalyst 5Ni–3Mg@γ-Al 2 O 3 was highly active and thermally stable for 12 h. • MgO and La 2 O 3 addition to the Ni-based catalysts lowered coke formation. • Increasing the water proportion in the feedstock favored the reforming reaction. [ABSTRACT FROM AUTHOR]

Inconsistent control of Echinochloa oryzoides has been reported repeatedly by farmers in the major rice growing area of Turkey. Greenhouse studies confirmed the existence of cross and multiple herbicide tolerance of E. oryzoides accessions including acetolactate synthase (penoxsulam, bispyribac-sodium) and acetyl CoA carboxylase (cyhalofob-butyl) inhibiting herbicides. Comparison of 95% lower confidence intervals of ED 90 derived from log-logistic dose–response curves, and twice the recommended field rates of the herbicides showed some, but not distinct separation of susceptible and tolerant accessions. We used a novel method to separate heterogeneous data without a priori knowledge of grouping into more than one group. On the basis of the distribution of ED 90 it was possible to identify two distinct groups of the 172 accessions tested, 78% were not controlled by ALS inhibitors (penoxsulam, and bispyribac-sodium) at recommended field rates; and 38% were not controlled by the ACCase Inhibitor (cyhalofob-butyl) at twice the field rates. The effective response level of ED 90 resulted in 64 and 14 tolerant accessions to ALS and ACCase, respectively. Fourteen accessions showed multiple resistances to ALS and ACCase Inhibitors. Some of the accessions were strongly tolerant to both herbicide modes of action and had 100% survival even at 6 times the recommended rates. Most of these tolerant accessions were from Marmara region, predominantly in Edirne and Balıkesir, which are the regions without any crop rotation. [ABSTRACT FROM AUTHOR]

Abstract: Developing more competitive rice cultivars could help improve weed management and reduce dependency on herbicides. To achieve this goal, an understanding of key traits related to competitiveness is critical. Experiments were conducted at Gelemen and Bafra districts of Samsun province in Turkey between 2008 and 2009 to measure the competitiveness of rice cultivars against Echinochloa crus-galli, a problematic weed in rice fields. Five rice cultivars (Osmancık, Kızılırmak, Karadeniz, Koral and Neğiş) and five E. crus-galli densities (0, 5, 10, 20, and 30 plants m−2) were used. Koral produced significantly more tillers than the other cultivars irrespective of E. crus-galli densities and reduced E. crus-galli tiller production by about 29.5% at Gelemen and 15.8% at Bafra at the highest weed density. E. crus-galli interference reduced rice height and there was a density dependent relationship. Koral was the most competitive cultivar; it maintained high biomass accumulation in early growth stages and suffered smaller reductions in plant height in the presence of E. crus-galli, compared to the other cultivars. In the absence of weed competition, Koral and Neğiş produced the highest yields at both locations. Stepwise regression analyses of the combined data from both years showed tillering capacity, early growth crop biomass, and plant height were critical traits related to competitiveness. These traits should be considered by plant breeders in their efforts to develop rice cultivars with enhanced competitiveness against weeds. Development of such cultivars could substantially reduce herbicide and labor inputs for rice production. [Copyright &y& Elsevier]