Ford, G. 2015. Glyphosate-resistant kochia (Kochia scoparia L. Schrad.) in Saskatchewan and Manitoba. Can. J. Plant Sci. 95: 345Á349. Previous surveys have documented the occurrence of glyphosate-resistant (GR) kochia in Alberta in 2011 and 2012. To determine the incidence of GR kochia in Saskatchewan and Manitoba, a stratified-randomized survey of 342 sites (one population per site) in southern and central regions of Saskatchewan and a similar survey of 283 sites in southern Manitoba was conducted in the fall of 2013. Mature plants were collected, seed threshed, and progeny screened by spraying with a discriminating glyphosate dose of 900 g ae ha Á1 under greenhouse conditions. Screening confirmed 17 GR kochia populations in nine municipalities in west-central or central Saskatchewan, but only two GR populations from different municipalities in the Red River Valley of Manitoba. While the majority of GR kochia populations in Saskatchewan originated in chemicalfallow fields, some populations were found in cropped fields (wheat, Triticum aestivum L.; lentil, Lens culinaris Medik.; GR canola, Brassica napus L.) and non-cropped areas (oil well, roadside ditch). In Manitoba, the two populations occurred in fields cropped to GR corn (Zea mays L.) and soybean (Glycine max L. Merr.). Agronomic and economic impact of this GR weed biotype is compounded because of consistent multiple resistance to acetolactate synthase-inhibiting herbicides. However, GR kochia is susceptible to dicamba, an increasingly important auxinic herbicide used for control of this multiple-resistant weed biotype. Pour e´tablir l'incidence de cette adventice GR en Saskatchewan et au Manitoba, les auteurs ont proce´deá`u ne enqueˆte ale´atoire stratifie´e a`342 sites (un peuplement par site) dans le sud et le centre de la Saskatchewan, puis ont effectue´une enqueˆte similaire a`283 sites dans le sud du Manitoba, a`l'automne 2013. Ils ont recueilli des plants matures, en ont re´colte´les graines et ont pre´se´lectionne´la proge´niture en la pulve´risant avec 900 g de glyphosate par hectare, en serre, aux fins de discrimination. La pre´se´lection a confirme´la pre´sence de 17 peuplements de kochie GR dans neuf municipalite´s du centre-ouest ou du centre de la Saskatchewan, mais seulement deux populations GR dans des municipalite´s diffe´rentes de la valle´e de la rivie`re Rouge, au Manitoba. Bien que la majorite´des peuplements de kochie GR de la Saskatchewan aient e´te´observe´s dans des jache`res chimiques, quelques-uns ont e´te´retrouve´s dans des cultures (ble´, Triticum aestivum L.; lentille, Lens culinaris Medik.; canola GR, Brassica napus L.) et sur des terrains en friche (puits de pe´trole, fosse´d'une route). Au Manitoba, les deux populations ont e´te´de´couvertes dans des champs de maı¨s GR (Zea mays L.) et de soja (Glycine max L. Merr.). L'impact agronomique et e´conomique de cette adventice GR est complexe, car la kochie pre´sente une re´sistance multiple aux herbicides qui inhibent l'ace´tolactate synthase. Ne´anmoins, la kochie GR est sen...

Knowledge of rooting systems and their vertical distribution in the soil profile for field crops is required for designing crop rotation systems that allow for effective use of soil water and nutrients. This study determined the vertical distribution in the upper 100 cm of the soil profile and the temporal growth patterns of roots for three pulses (Cicer arietinum L. chickpea, Pisum sativum L. dry pea, and Lens culinaris Medik. lentil) and three oilseeds (napus canola, juncea mustard, and Linum usitatissimum flax) and spring wheat (Triticum aestivum L.). Crops were grown in 150-mm-diameter, 1-m-long lysimeters under low- (rainfall only) and high- (rainfall + irrigation) water availabilities in a 2-year (2006–07) field study, in Swift Current, Canada. Root volumes increased significantly from the seedling stage, reached the maximum at the late-flowering, and declined to maturity; this temporal growth pattern was independent with water availability. On average, ~44% of the root volume was in the top 20-cm soil layer, 70% in the top 40 cm, and 90% in the top 60 cm. About 5% of the roots in pulse crops were located below 60 cm in depth, significantly less than the 12% for wheat, 13% for mustard, and 18% for canola. Under low-water conditions, Brassica oilseeds had greater root volume (33 mm3 cm–3) than wheat (27 mm3 cm–3), but under high-water conditions, root volumes were 27 mm3 cm–3 for the Brassicas and 32 mm3 cm–3 for wheat. Pulses had greatest root volumes under both low- (40 mm3 cm–3) and high- (42 mm3 cm–3) water conditions, with largest root diameters among crops evaluated, whereas flax the smallest. Rotating the shallower but larger diameter, thicker-rooting pulses with deeper but smaller diameter, thinner-rooting oilseeds or wheat may increase water- and nutrient-use efficiency at the system level.

Microbats perform important ecological services in agro-ecosystems, but several species are globally threatened by loss of roosting and breeding habitats. The successful conservation of bats in agricultural land requires adequate knowledge of their ecology. Using ultrasonic recorders, we studied the activity of insectivorous bats in areas of macadamia production in eastern Australia at two spatial scales: across woodland-orchard transects at the local scale and across three levels of fragmentation at the landscape scale. At the local scale, activity patterns of 'clutter' and 'edge' specialists were consistently higher in woodland patches, gradually decreasing towards isolated orchards, where only a few 'open' specialists were active. At the landscape scale, bat community activity was affected by the level of fragmentation, partly because three of the most recorded taxa (Austronomus australis, Saccolaimus flaviventris and Miniopterus australis) had their highest activity in less-fragmented areas. A distance-based model explained 24% of the bat community activity based on a combination of six environmental variables. Canonical correspondence analysis showed that a number of bat taxa were associated with open areas of macadamia, whereas other taxa were associated with increasing values of landscape composition, and arthropod and water availability. In addition, total bat activity was highly correlated with foraging rate. These results suggest that most bat taxa were influenced by proximity to woodland and the degree of fragmentation, and only few taxa were able to exploit isolated orchards. Environmental factors that promote bat activity could be exploited to strengthen conservation efforts. Preserving remnant woodland and promoting habitat heterogeneity will benefit several bat species. In particular, the foraging activity of 'edge' specialists could be fostered by increasing landscape connectivity and maintaining unobstructed water bodies near macadamia orchards. Considering that bats forage as they navigate these areas, conservation efforts could also bring benefits to farmers through pest-reduction services.

Integrated management strategies are required to minimize ascochyta blight, a fungal disease caused by Ascochyta rabiei (Pass.) Labrousse [teleomorph, Didymella rabiei (Kovachevski) v. Arx] in chickpea (Cicer arietinum L.). This study determined the effect of cultivars varying in plant architecture and plant population density (PPD) on the severity of ascochyta blight. Four desi chickpea (with pinnate leaves) and four kabuli chickpea (two with pinnate leaves and two with unifoliate leaves) were grown at 25, 36, 44, 53, and 62 plants m 22 (actual counts 3 wk after initial seedling emergence) at Swift Current from 2002 to 2005 and at Saskatoon in 2004 and 2005. Site-years had a significant effect on ascochyta blight epidemics, with the highest severity at Swift Current in 2005 and lowest at Saskatoon in 2004. Across site-years, ascochyta blight was most severe on 'Evans', followed by 'CDC Xena', and lowest on '222B-11'. Cultivars with pinnate leaves had lower blight severity than those with unifoliate leaves during all growth stages. At the latepod stage, severity in cultivars with pinnate leaves averaged 15% compared with 48% in unifoliate cultivars. Kabuli cultivars had higher severity than desi cultivars throughout the growing season, and at the late-pod stage, severity was 13% for the desi and 33% for the kabuli. There was a significant interaction between cultivar and PPD for blight severity. Ascochyta blight increased as PPD increased for the majority of the cultivars tested, with a few exceptions. Site-year accounted for the largest portion of the treatment variance in blight severity (69%), followed by cultivar type (25%), and then PPD (6%). Increasing PPD consistently increased seed yield per unit area, despite more disease on plants at higher PPD. Identifying optimum plant populations for groups of cultivars with similar plant architecture should be a component in an integrated strategy to minimize ascochyta blight in chickpea.

The results from a survey of bats in semi-arid Idalia National Park, central westernQueensland, are presented, with an analysis of habitat use, species richness, seasonal activity and reproductive patterns. Fourteen species were recorded: one megachiropteran, and thirteen microchiropterans in eight genera and three families. Significant range extensions were recorded for Vespadelus vulturnus, V. finlaysoni and Nyctophilus gouldi. Capture success using harp traps was unusually high, with 859 bats of nine species captured in 27 trap-nights (31.4 bats per trap-night). Two species (Chalinolobus gouldii and Scotorepens greyii) comprised almost 75% of all captures in harp traps. The remaining five species were recorded by means of echolocation call detection, cave searches and incidental observations. Bat species richness, abundance and capture success was greatest in riparian woodland and open forest adjacent to water; over 97% of captures in harp traps occurred at these sites. Breeding in most species appears to follow a seasonally monoestrous pattern with the ovarian and spermatogenic cycles being asynchronous. Sex ratios were close to parity but with a slightly higher proportion of females in some species in autumn. Females were generally larger and heavier than males.