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Malhi, S. S. and Gill, K. S. 2002. Effectiveness of sulphate-S fertilization at different growth stages for yield, seed quality and S uptake of canola. Can. J. Plant Sci. 82: 665-674. Canola (Brassica napus L. and B. rapa L.) is an important cash crop in the Prairie Provinces of Canada. The majority of canola is grown in the Parkland zone where many soils are deficient or potentially deficient in plant-available S for optimum seed yield of canola. Because canola has high S requirements and S is immobile in plants, its deficiency can occur any time during the growing season and drastically reduce canola seed yield, particularly on soils fertilized well with N and P. The objective of this study was to assess the effectiveness of sulphate-S fertilizer (potassium sulphate) applied using various application methods at seeding and during the growing season for yield, seed quality and S uptake of canola on S-deficient soils. Six field experiments (two sites per year from 1998 to 2000) were conducted on Grey Luvisol soils in northeastern Saskatchewan. Fertilizer treatments were no fertilizer, N (120 kg N ha -1 ) alone at seeding, S (30 kg S ha -1 ) alone at seeding, and N (120 kg N ha -1 ) at seeding + S (15 and 30 kg S ha -1 ) at seeding, bolting and flowering stages of canola. Methods of S application were surface broadcast and incorporated into the soil, sidebanded and seedrow placed at seeding, and topdressed and foliar sprayed at bolting and early flowering. Canola at all experimental sites showed severe S deficiency symptoms. Compared to N alone, N + S fertilization increased yield, oil content and S uptake of seed in all cases, increased yield and S uptake of seed + straw in most cases, while protein content of seed and S index (ratio of S uptake in seed to S uptake in seed + straw) were not influenced consistently. A trend of seeding > bolting > flowering time of S applications was generally shown by yield and S uptake of seed and seed + straw, and by S index. There were no noticeable differences among treatments applied at seeding. Topdressing at bolting and flowering tended to produce less seed yield than foliar-applied S in few cases and method of S application had no consistent effect on other parameters. Increasing the rate from 15 to 30 kg S ha -1 generally increased yield and S uptake of seed and seed + straw, but had no consistent effect on oil and protein contents in seed and S index. Fertilizer S alone tended to increase yield, oil content and S uptake of seed but had no effect on seed protein content. However, application of N alone tended to reduce yield, oil content and S uptake of seed while it had an inconsistent effect on yield and S uptake of seed + straw and S index. In conclusion, application of sulphate-S fertilizer on S-deficient soils improved yield, seed quality and S uptake of canola, with applications at seeding generally more effective than at bolting and early flowering stages. The results suggest that application of sulphate-S can correct S deficiency in canola if it occurs in the gro...

. 2000. Sewage water irrigation effects on some potentially toxic trace elements in soil and potato plants in northwestern India. Can. J. Soil Sci. 80: 465-471. Sewage water is used for irrigation to improve crop yields, but it may affect the soil and crop quality. The effects of discharging the effluents of a leather complex on the concentrations of some potentially toxic elements (Cu, Fe, Mn, Zn, Al, As, Cr and Ni) in sewage water and the effects of irrigation with contaminated sewage water on the concentrations of these elements in soils and in potato (Solanum tuberosum L.) leaves and tubers were studied near Jalandhar city, Punjab, in northwestern India. Two treatments were 10 yr of irrigation with 300 mm of sewage water + 300 mm of ground water per annum (SW) and with 600 mm of ground water per annum (GW). Soils of the study fields were Typic Ustochripts with sandy to loamy sand texture. The concentrations of all elements except As increased following the addition of leather complex effluents in the sewage water, with the biggest increase in the concentration of Cr (from 2.7 mg to 14.0 mg Cr L -1 ). The SW treatment increased concentrations of all elements in soil except As, and the increase was significant to 60 cm depth for Fe, Mn, Zn, Al and Ni and to 30 cm depth for Cu and Cr. Irrigation with SW also increased the concentrations of these elements in potato leaves and tubers and the increase was generally higher in leaves than in tubers. The proportional increase of Cu, Fe, Zn and Al was less in plants than in soils, that of Mn and Cr was almost similar in plants and in soil, and that of Ni was more in plants than in soil. These elements, which accumulate in soils and crops, may become health hazards to humans and/or animals. Therefore, continued monitoring of the concentrations of potentially toxic elements in soil and plants and/or treatment of sewage water before using for irrigation is needed.

Wheat streak mosaic is a damaging disease of cultivated bread wheat, Triticum aestivum L. em Thell., in many parts of the world. No wheat cultivar has a high level of resistance to WSMV or its vector, the wheat curl mite, Eriophyes tulipae Keifer. Genes conferring resistance to wheat curl mite colonization have been transferred from Aegilops tauschii Coss., Crncl, and from Agropyron elongatum (Host) Beauv., Cmc2. A gene conditioning resistance to WSMV, Wsml, was transferred from Agropyron intermedium (Host) Beauv. into common wheat. To broaden the genetic base of wheat, new sources of WSMV resistance are continuously sought. This study reports a new source of WSMV resistance derived from A. intermedium and its transfer into hexaploid wheat. C-banding analysis was used to cytogenetically identify the A. intermedium chromosomes and chromosome arms in three WSMV resistant wheat-A. intermedium derivatives, designated as 6957,6961, and 6962. All lines were identified as disomic chromosome addition lines with an A. intermedium chromosome arm in common. Restriction fragment length polymorphism analysis was used to establish homoeology of the A. intermedium chromosome arm carrying the gene or gene complex conditioning resistance to WSMV. The arm belonged to the long arm of the wheat Group 4 chromosomes, and was designated as 4Ai#3L. The added A. intermedium chromosomes present in Lines 6957 and 6961 probably originated from centricfusion. The WSMV resistance of these lines is different from that conditioned by Wsml and may have significance in breeding WSMV resistant wheat cultivars. W HEAT STREAK MOSAIC is a serious disease of cultivated bread wheat, Triticum aestivum L. em Thell. (2n = 6x = 42), in the Great Plains of the USA and in other wheat-producing areas of the world. Yield losses caused by WSM in Kansas averaged 2.6% over the last 20 yr (Christian and Willis, 1993). In 1988, an epidemic of WSMV in Kansas resulted in an estimated loss of about 13%, corresponding to 1.1 billion kg (Sim et al.,