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Abstract: There are currently no herbicides registered in Argentina for the selective control of grassy weeds in annual canarygrass (Phalaris canariensis L.). The principal grassy weeds are darnel ryegrass (Lolium temulentum L.) and wild oats (Avena fatua L.), which cause grain yield and quality losses. The potential of diclofop-methyl and clordinafop-propargyl for their control was assessed through greenhouse and field trials, in which crop phytotoxicity and weed control efficacy were evaluated. It was found that (i) field application of clordinafop-propargyl resulted in severe crop damage, except for low doses that did not affect the species to be controlled; (ii) although field application of diclofop-methyl resulted in a certain degree of phytotoxicity on wild oats, these effects were insufficient for efficacious control; and (iii) field and greenhouse application of diclofop-methyl between 200 and 500 g a.i. ha−1 revealed differences between crop sensitivity and that of darnel ryegrass. In this range, crop phytotoxicity in the greenhouse was less than 20% compared to more than 60% in the weed, and in the field only slight crop phytotoxicity symptoms were observed. As in the greenhouse, field application resulted in significant phytotoxic effects upon darnel ryegrass, high efficacy levels, a low survival rate amongst treated plants and a notable reduction in seed production by surviving plants. Only the highest dose (500 g a.i. ha−1) in one of the field trials resulted in a significant reduction in crop grain yield. Hence diclofop-methyl application appears to offer a promising means for controlling darnel ryegrass. [ABSTRACT FROM AUTHOR]

The article presents the results of the study made on the agronomic traits of 57 accessions of Canaryseed (Phalaris canariensis L.) in four field trials sown in the provinces of Buenos Aires, Argentina over a three-year period. For all traits scores including grain yield and its components, harvest index and percent lodging, genetic variation was found. The additive differences between accessions were observed to be sufficient for the identification of potential breeding materials.

Eleven cultivars of durum wheat from Argentina and Chile were analysed for their endosperm storage protein allelic composition and for industrial quality characteristics. For the HMW glutenin subunits, all cultivars carried the null allele Glu-A1c, and four variants were observed at Glu-B1: Glu-B1b (encoding subunits 7+8), Glu-B1d (subunits 6+8), Glu-B1e (subunits 20+20y) and Glu-B1z (subunits 7+15). For the Glu-3 encoded B-LMW glutenin subunits, alleles Glu-A3a (subunit 6), Glu-A3b (subunit 5), Glu-B3a (subunits 2+4+15+19), Glu-B3b (8+9+13+16) and Glu-B3c (2+4+14+15+19) were observed, and for the Glu-B2 encoded B-LMW glutenin subunits, Glu-B2a (subunit 12) and Glu-B2b (null allele). A B-LMW glutenin subunit not previously reported was observed in the cultivar Buck Cristal and provisionally designated subunit 6.1. A wide range of values for the characters gluten index, SDS-sedimentation volume and the Farinograph parameters energy level and tolerance was obtained from grain harvested from field trials sown in Argentina. There were strong correlations between these characters, and less strong correlations with grain protein and gluten content. While some cultivars varied for quality performance between years, others were relatively consistent for both extremes of performance. The analyses suggested that the gene pool represented by the cultivars investigated comprises useful variation for future breeding programmes, and provides pointers for directions that such programmes could take. [Copyright &y& Elsevier]

Abstract: Grain composition, industrial and end-use qualities were analysed in four cultivars of durum wheat subjected to four different nitrogen (N) and sulphur (S) fertiliser treatments in field trials conducted in two successive years in soils not deficient in S:N1S1 (both N and S applied), N1S0 (N application only), N0S1 (S application only) and N0S0 (no fertiliser application). Characters analysed were grain protein content (%P), grain sulphur content (%S), SDS-sedimentation (SDSS), Farinograph energy level (EL), Farinograph tolerance (TOL) and viscoelasticity of cooked pasta (VISCO). Important differences were found between the results from the 2 years, where all parameters showed superior performance in the year of lower rainfall and higher mean temperatures in the final phase of the crop cycle. Significant differences were observed between fertilisers and between cultivars for all parameters. In spite of the non-limiting conditions for S-availability, S-fertiliser application caused significant differences in grain %P, SDSS and N:S ratio, although it did not generate changes in rheological parameters and end-use; these latter parameters were only influenced by N-fertiliser application. For SDSS, the fertiliser treatment N1S1 was generally the best treatment. SDSS was, in general, strongly correlated with the rheological parameter EL and the end-use parameter VISCO, verifying the potential utility of this small-scale test in early generation selection during breeding. However, one cultivar, Chagual, with a very distinct glutenin and gliadin allelic composition compared to the other three cultivars, showed markedly inferior performance for SDSS and EL, yet acceptable performance for VISCO. Given that previous studies have shown that this cultivar shows superior grain yield compared to the other three cultivars, this sounds a cautionary note for the use of SDSS in breeding: selection based upon SDSS performance would have meant this valuable line would have been eliminated from consideration early in the breeding programme. [Copyright &y& Elsevier]