Cookies Notification

We use cookies to improve your website experience. To learn about our use of cookies and how you can manage your cookie settings, please see our Cookie Policy.
Volume 103 • Number 5 • October 2023


Vol. 103No. 5pp. 433–442
In this study, PsMYB2 was successfully cloned using cDNA from Potentilla sericea as a template. It was used to construct the plant overexpression vector pBI121-PsMYB2-GFP, which was transferred into Arabidopsis thaliana wild-type plants. We studied the gene function using real-time quantitative PCR and performed a preliminary characterization and analysis of the function of PsMYB2 under abiotic stresses. This study showed that under cadmium stress, the gene expression of PsMYB2 gene in roots, stems, and leaves was up to 3–6 times higher than the control. The germination rate of transgenic A. thaliana T3 generation seeds reached more than 95%. The O2·, H2O2, and malondialdehyde contents of the transgenic P. sericea plant lines were increased but lower than those of the wild-type strain. The superoxide dismutase, peroxidase, and hydrogen peroxidase activities were increased in both wild-type and transgenic strains, and the transgenic strains showed higher enzyme activities than the wild-type. We concluded that PsMYB2 could improve plant resistance to cadmium, which provides a theoretical basis for using transgenic plants to remediate cadmium-contaminated soil and for sustainable land use.
Vol. 103No. 5pp. 443–449
The sunflower (Helianthus annuus L.) is a commercially important cut flower requiring research into postharvest factors such as recutting, water uptake, stem number, cooling rate, and storage temperature to maximize vase life. Stems of 'Sunbright' sunflowers were either recut before or after a drying period up to 48 h. Water uptake, stem quality, and microbial counts were determined 4 days after rehydration. Water potential was determined on five corresponding leaves per treatment. The effects of stem number per vase were evaluated with either 1, 3, 5, or 10 stems. Effects of cooling rate were determined by temperatures of 5 °C for 3 days in the dark, 5 °C for 2 days in the dark preceded by 24 h at either 20 °C with light or 32 °C in a shaded area outdoors, or were maintained in a shaded area at 32 °C for 3 days. Hydration and storage temperature effects were determined by either transferring to a postharvest environment, 20 °C cooler for 2 h, immediate storage for 2 days at 5 °C, or 3 days at 5 °C after recutting the basal stem. Allowing stems to dry up to 48 h reduced vase life by 2.3 days or less. Vase life was unaffected by harvesting into water or by the number of stems in a vase but was affected by temperature such that the longest vase life of 13.2 days occurred when stems were stored for 3 days at 5 ± 0.5 °C followed by postharvest evaluation at 20 ± 1 °C.
Vol. 103No. 5pp. 450–462
Current research on deoxynivalenol (DON), a trichothecene secondary metabolite produced by the Fusarium species in corn grains, relies on the time-consuming field inoculation of Fusarium species with unpredictable and low recovery rates of DON in grains. The objective of this study was to evaluate three methods: soaking whole grains, soaking cracked grains, and injection in three solvents (distilled water, methanol, and acetonitrile) at three toxin concentration levels (1, 5, and 10 µg/g) for facilitating DON absorption in corn grains. The effectiveness of each treatment method and the performance of each solvent in aiding DON absorption were analysed and compared with the recovery rates of DON in the treated corn grains. The treatment methods, solvent, and DON concentration in solvent had significant effect on the recovery rate of DON in treated kernels. Injecting whole grains showed the highest recovery rates of DON (60%–108%) followed by soaking cracked grains (10%–87%) and whole grain (10%–72%) treatment methods. Distilled water showed the highest recovery rates in both soaking (53%–87%) and injection (74%–105%) treatment methods followed by methanol (18%–68% for soaking; 66%–103% for injection) and acetonitrile (10%–36% for soaking; 61%–108% for injection). Water dispersed the arrangement of starch granules but caused no changes in their surface morphology. Methanol and acetonitrile showed disruptive effects on the surface morphology of starch granules.
Vol. 103No. 5pp. 463–471
Wild oat is a widespread threat to annual crop production on the Canadian Prairies. Infestations are difficult to manage due to a persistent seedbank, complex dormancy, a long emergence window, herbicide resistance, and seed shatter corresponding to crop harvest timings. The study objective was to evaluate the efficacy of potassium nitrate (KNO3) and pyroligneous acid for promoting germination and emergence of wild oat and volunteer wheat, barley, and oat. A total of 24 repeated experiments were conducted using freshly produced seeds to ensure adequate endodormancy. Wheat and barley demonstrated no endodormancy following seed formation and rapidly emerged with moisture. All species imbibed but did not germinate in Petri dishes within pyroligneous acid solutions of 5%–100%. Dormancy release was observed within 0.1% and 1% pyroligneous acid solutions. KNO3 did not stimulate germination or emergence for any species and was inhibitory at 125 kg N ha−1. Pyroligneous acid increased wild oat emergence with 50% and 100% solutions applied at 200 L ha−1 in the first study and with 10% solutions in the second study. Emergence inhibition was noted for oat, barley, and wheat with pyroligneous acid applications. This research further confirms that pyroligneous acid may stimulate wild oat emergence and confirms activity on freshly matured seed.
Vol. 103No. 5pp. 472–480
Kochia (Bassia scoparia (L.) A.J. Scott) is a problematic tumbleweed, which infests row crops and ruderal areas within western Canada. Herbicide resistance makes kochia management challenging for producers. Widespread resistance to acetolactate synthase-inhibitors, evolution and spread of glyphosate resistance, and the occurrence of dicamba resistance has been previously noted in Saskatchewan. This study's objective was to evaluate the occurrence and distribution of glyphosate- and dicamba-resistant kochia in central and southern Saskatchewan. A randomized, stratified survey was conducted in the fall of 2019 at 303 sites. Rotational history was obtained using the Agriculture and Agri-Food Canada Annual Crop Inventory. Kochia samples were collected from cropped fields (78%), ditches (17%), oil well sites (2%), and railway grades (3%). Glyphosate resistance was detected in 87% of samples (n = 275) within 137 Rural Municipalities (RMs). Dicamba resistance was detected in 45% of kochia samples (n = 255) in 87 RMs. Crops infested with herbicide-resistant kochia included wheat (Triticum aestivum L. and T. durum Desf.), canola (Brassica napus L.), lentils (Lens culinaris Medik.), barley (Hordeum vulgare L.), flax (Linum usitatissimum L.), and peas (Pisum sativum L.). Reducing the soil seedbank and preventing dispersal will be critical to mitigating resistance. Good herbicide stewardship including mixing multiple modes of action is paramount. Cultural strategies to increase canopy closure and crop competitiveness to limit biomass and seed production are recommended. Kochia occupies many environments outside of cropped fields, and a community-wide management approach may be necessary to reduce dispersal potential of tumbling plants that disperse seed.
Vol. 103No. 5pp. 481–493
Plants regulate various biological activities in cells by producing reactive oxygen species (ROS) as signal molecules. Plant NADPH oxidases, respiratory burst oxidase homologues (Rbohs), are the main source of ROS and participate in a variety of plant physiological processes. However, there are few studies regarding the function of Rbohs in rhizobium–legume symbiotic nodulation. A Rbohs subfamily gene GmRbohK was cloned and the gene expression and its subcellular localization were studied. The GmRbohK gene was highly expressed in soybean roots and nodules and greatly induced by rhizobia. GmRbohK was located at the cell membrane of Arabidopsis protoplasts. Moreover, RNA interference (RNAi) of GmRbohK resulted in a decrease in the number of nodules and nitrogenase activity. Meanwhile, the expression levels of nodulation marker genes decreased in association with the decrease in GmRbohK expression level. RNAi of GmRbohK inhibited the production of ROS and blocked infection events at the initial stage of nodule formation. Further analysis of nodule tissue sections revealed that RNAi of GmRbohK significantly reduced the number of bacteroids in the nodule infection area. In conclusion, GmRbohK is heavily involved in the regulation of soybean nodule formation.
OPEN ACCESSEditor's choice
Vol. 103No. 5pp. 494–506
Winter survival of Vitis vinifera Linnaeus in cool climate viticultural areas can be jeopardized due to inadequate cold hardiness. Dehydrins are a family of proteins commonly found in plant tissue in response to dehydration stress and cold exposure. To determine their presence and relationship to cold hardiness in overwintering grapevines, compound buds of V. vinifera cv. Sauvignon blanc were sampled from a commercial vineyard every 2–3 weeks throughout the 2016–2017 winter. Proteins were extracted and separated by SDS–PAGE, and potential dehydrins were immunoblotted with a commercial antibody raised against the dehydrin K-segment consensus sequence. Six protein bands were identified in four Sauvignon blanc clones at 23, 26, 35, 41, 48, and 90 kDa, showing a serological relation to dehydrins due to their reaction with the K-segment antibody. The bands at 23, 41, 48, and 90 kDa were confirmed as dehydrins following trypsin digestion and liquid chromatography with tandem mass spectrometry with Mascot analysis. Their fluctuations throughout the dormant season were quantified by immunoblotting, and three patterns emerged, the 23, 26, and 35 kDa proteins peaked immediately prior to deacclimation; the 41 and 48 kDa proteins peaked during maximum hardiness and decreased towards deacclimation, while the 90 kDa plateaued during the same period. Maximum hardiness and relative dehydrin band intensity were positively correlated (p < 0.050) for all but the 23 kDa protein. The variation in accumulation patterns and relationships to cold hardiness indicates that these dehydrin proteins are likely regulated by different molecular processes and could play different roles in cryoprotection throughout dormancy.

Short communication

Vol. 103No. 5pp. 507–511
The green manure residual effect on soil health 2 years later in crop rotation is understudied. Little is known about weed biomass impact on soil microbial communities or their interactions. A Colchester County, NS, Canada, organic grain research trial during 2016–2017 comprised 2 or 3-year rotations with or without green manure crop prior to wheat, and then soybeans. Fall soil sampling was conducted both years. The soybean phase of the crop rotation was managed as weedy or non-weedy. Weedy soil showed significantly increased soil respiratory activity and fungal microbial biomass. Green manure treatments did not significantly influence soil health indicators.

Cultivar description

Vol. 103No. 5pp. 512–518
AAC Connery, a doubled haploid awnless hard red spring wheat (Triticum aestivum L.), was similar in grain yield to CDC Osler and significantly higher yielding than the other check cultivars Katepwa, CDC Teal, and AC Splendor. Wheat and flour protein concentrations were within the range of the checks. AAC Connery matured significantly later than AC Splendor and in a comparable number of days as Katepwa, CDC Teal, and CDC Osler. AAC Connery was significantly shorter than all of the checks and was significantly more resistant to lodging than Katepwa, AC Splendor, and CDC Osler. AAC Connery had significantly heavier kernel weight than Katepwa, CDC Teal, and AC Splendor. The test weight of AAC Connery was within the range of the checks. End-use quality specifications of AAC Connery are suitable for the Canada Western Red Spring wheat market class. AAC Connery expressed moderate resistance to Fusarium head blight, an improvement over the checks, resistance to prevalent races of stem rust and yellow rust, and moderate resistance to leaf rust, loose smut, and common bunt.
List of Issues
Volume 103
Issue 6
December 2023
Volume 103
Issue 5
October 2023
Volume 103
Issue 4
August 2023
Volume 103
Issue 3 (Suppl. 1)
June 2023
Volume 103
Issue 3
June 2023
Volume 103
Issue 2
April 2023