The mechanical properties of leaves are important in many aspects of plant science. Because of their delicate structure, leaves are sensitive to different, potentially harmful, environmental factors. The mechanical properties of leaves are important factors affecting leaf quality, longevity, susceptibility to damage, and decomposition. Two growth stimulants were applied to investigate selected mechanical properties of Solomon’s seal Variegatum [Polygonatum multiflorum (L.) All.] leaves grown under field cultivation and in an unheated polytunnel. The mechanical properties of leaves were assessed by measuring Young’s modulus. The agents used in the treatment were Actisil Hydro Plus at a concentration of 0.4% in the first series and Pentakeep V at a concentration of 0.04% in the second series. Foliar treatment with the stimulants was conducted six times at weekly intervals. The control plots were sprayed with distilled water. The research was carried out between 2012 and 2014. In comparison to the test series, the respective effects of Actisil Hydro Plus and Pentakeep V on the change in Young’s modulus was more notable in plant leaves obtained from the tunnel than those from field cultivation. Specifically, growth stimulants had more impact on the stiffness of leaves obtained from plants grown in the tunnel. Generally, plant leaves from field cultivation were stiffer than those from the tunnel.

The transportation and distribution of sucrose in plants is mediated by sucrose transporters (SUTs), which also participate in various plant developmental and resistance processes. However, no such study of the tobacco SUT family has been reported yet. In the present study, 11, 5, and 4 SUT genes were identified from the genomes of Nicotiana tabacum, Nicotiana sylvestris, and Nicotiana tomentosiformis, respectively. The exon–intron structures of the tobacco SUT genes were highly conserved in the three tobacco species. Gene loss, duplication, and chromosome exchange occurred in the NtSUT family during the formation of allotetraploid common tobacco. Expression profiling analysis revealed that the expression patterns of the NtSUT genes in common tobacco were closer to those in N. sylvestris plants. The NtSUT2s and NtSUT4 genes were ubiquitously expressed in various tobacco tissues, while the NtSUT1s gene was highly expressed in the maturing leaves, indicating their functional conservation and differentiation. The transcriptions of the NtSUT2t, NtSUT3s, NtSUT4, and NtSUT5s genes in tobacco plants were dramatically induced under Pi starvation, drought, and salinity stresses, but their highest expression levels occurred in different tissues, suggesting the multiple roles of NtSUTs in plant resistance to various abiotic stresses. This study provides useful information for the further functional characterization of SUT genes in tobacco.

Cercospora leaf spot (CLS) caused by Cercospora traversiana is an important phyto-pathological problem of fenugreek (Trigonella foenum-graecum L.), a multiuse legume crop. Field screenings for resistant plants, although accurate and effective, demand significant time and a sizable workforce to accomplish. Also, weather conditions in the field may not always be favourable for uniform disease spread, which eventually may lead to failure of the overall experiment. Whole-plant assays (WPA) and detached leaf assays (DLA) with artificial inoculation not only help in scaling up the number of plants screened but also reduce the space, time, and amount of inoculum needed for the experiment. The results from our two experiments indicate that both the WPA and DLA methods can be used reliably to differentiate resistant and susceptible genotypes of fenugreek. In addition, the correlation coefficient between WPA and DLA (r = 0.875, P < 0.01), derived from the mean disease score of each genotype, shows that they can be used interchangeably while screening fenugreek for CLS. DLA was found to be temperature-sensitive for the development of CLS symptoms and wounded leaves developed symptoms faster than non-wounded leaves. These indoor methods can be used for the development of CLS-resistant fenugreek cultivars in areas where disease development is difficult under field conditions.

The amino acid asparagine is considered the rate limiting precursor in the formation of acrylamide in cereal-based baked foods. However, there are no data on the quantity of this precursor in Canadian wheat. Wholemeal and white flour samples obtained from 30 Canadian hard red spring wheat grown in the Prairie provinces were analysed for asparagine content by liquid chromatography. The asparagine content varied from 302 to 965 and 116 to 336 μg g⁻¹ for wholemeal and white flour, respectively. Therefore, wheat grown in Canada has similar asparagine levels to wheat grown in other parts of the world. Analysis of variance suggested that asparagine content is significantly affected by genotype (p < 0.001), suggesting that breeding strategies could be investigated to produce cultivars with lower levels of this amino acid. Few significant correlations were observed between wheat and flour quality parameters and asparagine content, although there was a tendency towards weaker dough strength indices with increasing asparagine content.

The Salt Overly Sensitive (SOS) signal transduction pathway is pivotal in Na⁺ efflux and facilitates ion transport and homeostasis for improved salt tolerance in plants. Ten alfalfa varieties were used as experimental materials and two alfalfa regeneration systems were established and optimized. Cotyledons and hypocotyls were initially used as explants to induce embryogenic callus via the indirect production of somatic embryos to establish a callus acceptor system. Cotyledonary nodes were used as explants to induce adventitious bud formation via direct organogenesis, thereby establishing an in vitro regeneration system that could be used for the genetic transformation. Agrobacterium-mediated transformation of the cotyledonary nodes of the alfalfa ‘Golden Empress b’ was used to generate 25 independent sources of transformed plants exhibiting herbicide tolerance. Four of the positive transgenic plants were randomly selected for southern blot analysis, and three hybridization signals with one or two copies were detected. Reverse transcription polymerase chain reaction showed that the Bialaphos resistance (Bar) and SOS1 genes were expressed in transgenic plants and that multiple exogenous salt-tolerant genes were integrated into the transgenic plant genome and expressed at the transcriptional level. The overexpression of Arabidopsis SOS genes in alfalfa conferred a high degree of salinity tolerance, enhanced plant growth, lowered the accumulation of Na⁺, increased the accumulation of K⁺ in the leaves, and altered physiological and biochemical parameters in response to salt stress.

Waterhemp is a competitive, summer annual, broadleaf weed that poses a considerable threat to Ontario grain farmers. Populations with multiple resistance to Group 2 (ALS-inhibitors), Group 5 (photosystem II inhibitors), and Group 9 (EPSPS inhibitors) herbicides have been confirmed in Ontario. If left uncontrolled, waterhemp competition can result in corn yield losses of up to 74%. The objective of this research was to evaluate preemergence (PRE) and postemergence (POST) herbicides for control of multiple-herbicide resistant (MR) waterhemp. Two field studies at two locations (Cottam and Walpole Island) were conducted in 2016 and 2017. Fifteen PRE and 12 POST herbicides were evaluated for waterhemp control, density, and aboveground biomass and corn yield. At 8 wk after application (WAA), S-metolachlor/mesotrione/atrazine (1393/139/524 g a.i. ha⁻¹) and S-metolachlor/mesotrione/bicyclopyrone/atrazine (1259/140/35/588 g a.i. ha⁻¹) applied PRE were the most efficacious, controlling MR waterhemp 87% and 91%, respectively. At 8 WAA, the most efficacious POST herbicides were mesotrione + atrazine and dicamba/atrazine, controlling MR waterhemp 92% and 87%, respectively. Reduced waterhemp interference with the PRE herbicides evaluated resulted in corn yield that was similar to the weed-free control.

The objective of this study was to determine the effect of premixed glyphosate/dicamba application timing and rate on glyphosate-resistant (GR) waterhemp control. Glyphosate/dicamba applied to 5-, 15-, and 25-cm-tall plants, controlled GR waterhemp 81%, 73%, and 61% at 2 wk after application (WAA) and 61%, 68%, and 72% at 8 WAA, respectively.

Halosulfuron (35 g a.i. ha⁻¹) applied preemergence (PRE), early-postemergence (EPOST), and late-postemergence (LPOST) does not adequately control volunteer adzuki bean in white bean, but halosulfuron applied EPOST and LPOST has the potential to be used for control of volunteer soybean in white bean.

Research was conducted in 2017 and 2018 to determine the relative efficacy of five HPPD-inhibitors, tank-mixed with atrazine, for the control of multiple herbicide resistant waterhemp. At 12 wk after application (WAA), isoxaflutole + atrazine, mesotrione + atrazine, and tembotrione + atrazine, applied preemergence (PRE), controlled waterhemp 90%, 87%, and 81%, respectively. None of the HPPD-inhibiting herbicides applied PRE controlled waterhemp similar to the weed-free control 12 WAA. Applied postemergence, topramezone + atrazine, mesotrione + atrazine, tolpyralate + atrazine, and tembotrione + atrazine controlled waterhemp 87%, 94%, 97%, and 98% 12 WAA, respectively, and were all similar to the weed-free control.

A survey was conducted in Alberta in 2017 to determine the distribution and abundance of acetolactate synthase (ALS) inhibitor and glyphosate resistance in Russian thistle. Of 45 populations tested, 31 (62%) were ALS inhibitor resistant. No populations exhibited resistance to glyphosate. This survey serves as a baseline to monitor future incidence of resistance in this weed.

CO465 is a short-season corn (Zea mays L.) inbred line with excellent combining ability with Iodent inbred testers and the early maturing AAFC line CL30. CO465 has moderate resistance to eyespot and intermediate resistance to common rust, northern corn leaf blight, and fusarium stalk rot.

CO467 is a short-season corn (Zea mays L.) inbred line with excellent combining ability with stiff stalk inbred testers and the early maturing AAFC line CL30. CO467 has intermediate resistance to eyespot and common smut.

AAC Expedition is a high-yielding pinto dry bean (Phaseolus vulgaris L.) cultivar with a semi-upright, indeterminate bush (type IIb) growth habit, large seed size, low percentage of hard seed, and bright seed coat colour. Its improved seed quality traits, particularly its bright seed coat colour, low percentage of hard seeds after soaking, and high yield potential, will make AAC Expedition a preferred pinto bean cultivar for commercial production. AAC Expedition, developed by the Agriculture and Agri-Food Canada Lethbridge Research and Development Centre, Lethbridge, AB, is well suited for commercial production under irrigation in Alberta and Saskatchewan.

HS-181 is an 11S glycinin null food-grade soybean line [Glycine max (L.) Merr.] with yellow hilum. The absence of 11S subunits would result in a relatively higher concentration of 7S β-conglycinin in soy food. β-conglycinins suppress food intake, which can help to fight obesity. HS-181 is adapted to areas of southwest Ontario with 3100 or more crop heat units and has a relative maturity of 2.5 (MG 2.5).

CO466 is a short-season corn (Zea mays L.) inbred line with excellent combining ability with both Iodent and stiff stalk inbred testers, and the early maturing AAFC line CL30. CO466 has moderate resistance to eyespot, Goss’s bacterial wilt, grey leaf spot, common rust, and fusarium stalk rot.