Cercospora leaf spot (CLS), caused by Cercospora traversoana, is an important phyto-pathological problem of self-pollinated fenugreek (Trigonella-foenum graecum). Developing resistant genotypes in crop plants has been considered the best option to control diseases for economic, environmental, and social reasons. However, before this can be accomplished, knowledge about the inheritance of disease-resistant genes is necessary for creating high-yielding resistant genotypes. One susceptible fenugreek cultivar, Tristar, and two resistant accessions L3717 and PI138687 were used in two-way crosses using hand emasculation and pollination technique in a greenhouse. F₁ plants were grown in a greenhouse and allowed to grow till maturity to produce F₂ seeds. Some flowers from F₁ plants were crossed back to both resistant and susceptible parents separately to generate backcross (BC₁) seeds. Parents, F₁, F₂, and BC₁ populations were grown in the greenhouse using a RCBD with four replications. Plants were inoculated 30 d after sowing with a suspension of C. traversoana at 2 × 10⁵ conidia mL^-1. Symptoms were observed and rated on individual plants 25 d after inoculation, and plants were categorized according to susceptible or resistant reactions based on rating scores. Mean disease score was significantly different (p < 0.0001) among generations. In both the cross combinations, results showed CLS resistance in fenugreek (from L3717 and PI138687) was governed by a single dominant gene which is moderately heritable (46% narrow sense heritability). This indicates a relatively simple pathway for transfer of genes to adapted fenugreek cultivars.

Two multi-year experiments were conducted to determine the influence of planting density and rootstocks on the performance of Montmorency tart cherries (Prunus cerasus L.). Using a constant between-row spacing of 4.5 m, three in-row tree spacings of 4, 3 and 1.5 m were tested with five rootstocks: Weiroot 13, Gisela 6, Krymsk 6, Krymsk 7, and a Prunus mahaleb control. In a second experiment, the comparative effects of five rootstocks spaced 4.5 m × 1.35 m were evaluated: (i) P. mahaleb, (ii) Weiroot 10, (iii) Weiroot 13, (iv) Weiroot 72, and (v) Weiroot 158. With higher tree density, yields increased and tree vigour declined. At higher densities, Weiroot 13 was up to 43% and Gisela 6 16% smaller than Mahaleb, whereas Krymsk 6 and 7 were similar in size to Mahaleb. At the highest density, Mahaleb reduced tree size by 20%. After 7 yr, tree mortality on Krymsk 6 and 7 was greater than the other rootstocks, as was the number of root suckers on Krymsk 7. Cumulative yields, yield efficiency, fruit quality characteristic, and light interception were also markedly influenced by planting density and rootstocks. Overall, evaluated rootstocks ranged in size control from slight to semi-dwarfing, and several showed promise in terms of their induction of high-yield precocity and yield efficiency of the scion. Weiroot selections and Gisela 6 had the greatest beneficial effects on productivity and yield efficiencies. Under experimental conditions, Krymsk 6 and 7 were unsuitable because of their lower cumulative yields and high rate of mortality, respectively.

Sustainable production of biomass crops is important in the development of feedstocks for the production of biofuels and other bioproducts. This study investigates the use of nine beneficial soil microbes and a plant biostimulant (i.e., Ascophyllum nodosum seaweed extract) to increase the growth of two giant Miscanthus (Miscanthus × giganteus) cultivars, ‘Amuri’ and ‘Nagara’, under greenhouse conditions and in the field on poor-quality, marginal land. Greenhouse trials indicated increases in shoot dry weight (DW) in ‘Amuri’ in treatments with Gluconacetobacter diazotrophicus PAL5T LsdB⁺⁺, Gluconacetobacter johannae UAP-Cf-76, and Variovorax paradoxus JM67 by 15%–24% compared with untreated controls. In ‘Nagara’, shoot DW was increased in the treatments with Penicillium bilaiae by 11% and the seaweed extract by 10%. The nutrient content of shoot tissues increased in the same treatments in which biomass was increased. Despite a lack of treatment effects on shoot DW in ‘Amuri’ in the field, several treatments increased Fe and Zn content in shoots by up to 1.9×. In ‘Nagara’ in the field, treatment with G. johannae UAP-Cf-76 and the seaweed extract resulted in increases in shoot DW by 16% and 23%, respectively, and several treatments resulted in increases in shoot Fe and Zn concentrations. The productivity enhancements in giant Miscanthus by beneficial soil microbes and the seaweed extract may be associated with increasing access to limited soil nutrients. These findings suggest that the use of beneficial soil microbes and plant biostimulants may aid in the sustainable production of giant Miscanthus on marginal lands.

Anthracnose, caused by the fungus Colletotrichum lindemuthianum (Sacc. & Magnus) Briosi & Cavara, is one of the most destructive diseases of dry bean (Phaseolus vulgaris L.) in the world. Between 2005 and 2015, commercial fields of dry beans in Manitoba and Ontario were surveyed to determine the frequency of occurrence of races of the anthracnose fungus. Throughout the study, race 73 was most prevalent in Manitoba and Ontario. However, three anthracnose races not previously reported in Canada also were identified. These three new races and four previously identified anthracnose races were used to screen 52 dry bean cultivars, as well as a mung bean and azuki bean cultivar from Ontario, for their seedling reactions to determine their patterns of race resistance. The dry bean cultivars were classified into a total of 19 resistance spectra based on the pattern of seedling reactions to the seven anthracnose races. The most common resistance spectrum was susceptible to the majority of the anthracnose races and no cultivar was resistant to all of the races. Many bean cultivars produced intermediate anthracnose ratings to races 31 and 105 and tests of 16 dry bean cultivars against those races indicated that all cultivars with intermediate ratings to a specific race were segregating in their seedling reactions and none of the cultivars produced plants with only intermediate anthracnose severity ratings. This study provides new information on the anthracnose reactions of common bean cultivars in Canada, which should be useful for the development of new bean cultivars with durable resistance.

The apparent efficacy of linuron to control pigweeds (Amaranthus spp.) has declined in Ontario, Canada, in past decades, possibly due to resistance. Samples were collected in multiple fields across Ontario with reported linuron failure. These were characterized at the whole-plant and molecular levels. Screening with linuron revealed resistance in six out of nine green pigweed (Amaranthus powellii Wats.) populations and 36 out of 38 populations of redroot pigweed (Amaranthus retroflexus L.). Sequencing of the psbA gene showed resistant plants had mutations conferring resistance to photosystem II (PSII) inhibitors. The most commonly seen mutation was coding for a Val₂₁₉Ile substitution, while other populations had Ala₂₅₁Val or Phe₂₇₄Val. Two populations were documented with a double mutation at Val₂₁₉Ile and Phe₂₇₄Val. All substitutions endowed plants with low to moderate resistance to linuron, with various levels of cross resistance to other PSII inhibitors. The double mutants were characterized by higher levels of resistance to linuron and diuron compared with each single substitution. The widespread failure of linuron to control pigweed species in many carrot fields in Ontario is due to the selection of PSII mutants. This is the first report of double mutation in psbA in any weed species and the first report of Ala₂₅₁Val and Phe₂₇₃Val in pigweed species. The presence of a double mutation is probably the result of continuous selection of plants already resistant due to a single mutation. Our results illustrate the need for diversified weed management strategies in crops where herbicide options are limited.

In this study, we analyzed the morphological, cytological, and molecular changes induced by different doses of ⁶⁰Co-γ radiation on root cuttings of the ground-grown chrysanthemum ‘Pinkling’ plants whose survival and height were decreased with increasing radiation dose. A variety of mutants were observed among irradiated ‘Pinkling’ plants; floral mutations included alteration of floral types, term ligulate floret number, capitulum diameter, and floral colour. Meiotic observation of mutants showed that the frequency of chromosome aberrations increased with radiation dose. The mutants were further analyzed using ISSR markers and on the basis of polymorphic DNA banding patterns, floral mutants were genotypically distinguished. Eighteen polymorphic ISSR primers produced 110 scorable bands, of which 93 (84.5%) were polymorphic. The percentage of polymorphism ranged from 60% to 100%. Jaccard’s dissimilarity coefficients varied from 0.337 to 1.000, which attested to the high genetic variability induced by irradiation. It is concluded that gamma ray irradiation induces a sufficient frequency of mutations and that ISSR analysis may offer a useful molecular marker for the detection of mutants in chrysanthemum. The present findings provide valuable information for future breeding of ‘Pinkling’.

Different extracts prepared from wastes (barks, branches, needles, or leaves) of different trees (grey alder, balsam fir, American larch, red maple, sugar maple, white spruce, black spruce, jack pine, white pine, quaking aspen, sweet cherry, and northern red oak) were investigated for their potential use as antibacterial agents for the management of lettuce varnish spot and bacterial leaf spot caused by Pseudomonas cichorii (Swingle) Stapp and Xanthomonas campestris pv. vitians (Brown) Dye, respectively. Extracts were first screened for their antibacterial activities against P. cichorii and X. campestris pv. vitians using the in vitro disk diffusion assay. Based on the diameter of the inhibition zone, ethanol (95%) extract prepared from sugar maple autumn-shed leaves (SMASL) and aqueous ethanol (50%, v/v) extracts prepared from SMASL and from sugar maple green leaves showed the strongest antibacterial activities. Ethanol (95%) SMASL extract was further investigated for its efficacy to manage bacterial diseases when applied on lettuce plants grown in the greenhouse. Foliar application of ethanol (95%) SMASL extract at a concentration of 3.2 g L^-1 was shown to significantly (P ≤ 0.05) reduce bacterial leaf spot severity compared with the control without causing phytotoxicity symptoms that could prevent the commercial marketing of the lettuce. Ethanol (95%) SMASL extract (1.6 and 3.2 g L^-1) was also shown to significantly reduce varnish spot severity in one experiment out of two. This study identifies for the first time the possibility of exploiting SMASL to manage bacterial diseases affecting horticultural crops.

BBX transcription factors are known to regulate the flowering time and the plant response to various abiotic stresses, but their functions in chrysanthemum have yet to be thoroughly explored. Here, a chrysanthemum homolog of the Arabidopsis thaliana gene AtBBX29 was isolated and characterized. The gene was transcribed in various plant organs but most strongly in the root and in the ligulate flowers. Its temporal pattern of transcription mirrored that of CmCO, the chrysanthemum homolog of the key flowering regulator CONSTANS (CO). Its constitutive expression in A. thaliana induced a delay to flowering, suppressing the transcription of FLOWERING LOCUS T (FT), SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1), LEAFY (LFY), and APETALA 1 (AP1), while promoting that of FLOWERING LOCUS C (FLC). Our results indicate that CmBBX29 can regulate flowering time in A. thaliana by the integration of FLC and the photoperiod pathway.

Pollen-mediated gene flow was analyzed in two managed fields of lowbush blueberry (Vaccinium angustifolium Ait.) in Maine. Seedlings derived from open-pollinated crosses of two mother plants, one from each of the two fields, were genotyped using simple sequence repeat markers. The mother plants, the four to five nearest neighbour plants, and a group of 22–23 plants further away from the site of fruit collection were genotyped as well. The paternity of 70 seedlings produced by the mother plants, 35 from each field, was analyzed using FAMOZ to determine if each seedling was most likely a result of a self-cross, a cross with one of the nearest neighbours, or a cross from outside the nearest neighbourhood. Approximately 91%–97% of the seedlings appeared to result from crosses with plants outside the nearest neighbourhood, whereas 0% appeared to have resulted from self-crosses. This suggests that the primary pollinators of lowbush blueberry, native bees and honey bees, routinely collect and move pollen from distances greater than the adjacent neighbours of the plants receiving the pollen.

The worldwide increase in demand for plant-derived drugs has increased interest in medicinal plants as alternative cash crops across western Canada. The objective of this research was to determine if the Northern Vigor^® phenomenon, expressed as a combination of elevated crop yield and phytomedicinal quality in crops grown in northern latitudes, exists in narrow-leaved purple coneflower (Echinacea angustifolia DC.). In a 2-yr study, narrow-leaved purple coneflower was grown in three field sites in Saskatchewan, Canada (SK; Saskatoon, La Ronge, and Outlook) and one field site in Oregon, United States (Madras), to test the effects of latitude on root yield, phenolic, and alkylamide phytochemical markers. Roots harvested in 1999 (all three SK sites) and 2000 (two SK sites) had higher root biomass compared with roots harvested in Oregon. Root echinacoside and cynarin content were significantly higher in both years in the three Saskatchewan sites compared with Madras, whereas root chlorogenic acid content and total alkylamides were significantly higher in all three Saskatchewan sites in 1999. In 2000, root chlorogenic acid content and total alkylamides were higher in two of the three Saskatchewan sites compared with Madras. While Aster Yellows were prevalent in Echinacea in Saskatchewan, this disease did not significantly decrease root yield phenolic or phytochemical content. These data suggest that Saskatchewan has a competitive advantage in producing premium-quality narrow-leaved purple coneflower root in North America.

AAC Ling is a two-row spring feed barley (Hordeum vulgare L.) cultivar with high grain yield, high straw yield, and good lodging resistance. It was tested as CH2720-5 in the Atlantic Recommending Committee for Cereal Crops (2015–2017), Quebec Recommending Committee for Cereal (2015–2017), and Ontario Cereal Crops Committee (2016–2017) trials before being registered by the Canadian Food Inspection Agency in 2018. AAC Ling was developed by the Ottawa Research and Development Centre, Agriculture and Agri-Food Canada, Ottawa, ON. AAC Ling is recommended for barley growing areas in eastern Canada.

AAC Bell is a two-row spring feed barley (Hordeum vulgare L.) cultivar with high yield, heavy kernel weight, and good lodging resistance. It was tested as CH2714-4 in the Atlantic Recommending Committee for Cereal Crops (2015–2017), Quebec Recommending Committee for Cereal (2015–2017), and Ontario Cereal Crops Committee (2016–2017) trials before being registered by the Canadian Food Inspection Agency in 2018. AAC Bell was developed by the Ottawa Research and Development Centre, Agriculture and Agri-Food Canada, Ottawa, ON. AAC Bell is recommended for barley growing areas in eastern Canada.

Glencross is a hard red spring wheat (Triticum aestivum L.) adapted to the wheat-growing regions of the Canadian Prairies, particularly where orange blossom wheat midge is a production constraint. Glencross was evaluated in the High Yielding Red Wheat Cooperative Test in 2004, 2005, and 2006. Glencross had grain yield similar to the Canada Western Extra Strong (CWES) checks, Glenlea and CDC Rama, as well as the Canada Western Red Spring check, Superb; however, Glencross was significantly (P < 0.05) earlier maturing than all checks by 3 (Superb) to 4 (Glenlea and CDC Rama) days. Glencross had plant height and lodging scores similar to the CWES checks, Glenlea and CDC Rama, but was significantly taller and had significantly higher lodging scores compared with the CWRS check, Superb. Glencross was moderately resistant to moderately susceptible to leaf rust but was highly resistant to stem rust and loose smut. Glencross showed an intermediate reaction to common bunt and was similar to the susceptible checks for Fusarium head blight. Glencross is the first CWES cultivar with resistance to the orange blossom wheat midge (Setodiplosis mosellana Géhin). Glencross demonstrated end-use quality suitable for all grades of the Canada Western Extra Strong wheat class.

Jake hard red spring wheat (Triticum aestivum L.) was developed using a modified bulk breeding method at the University of Alberta, Edmonton, AB. Jake is an awned, hollow-stemmed line with high yield potential, medium tall plants, and medium maturity. During the three years (2015–2017) of evaluation in the Parkland Wheat Cooperative test, Jake yielded 6% higher than the mean of all of the checks, and matured 0.7 and 1.7 d later than Parata and Splendor but 2.9 d earlier than Glenn. Jake was 91.2 cm tall, shorter than AC Splendor (95.8 cm), but similar in height to Glenn (91.8 cm) and Parata (92 cm). The lodging score of Jake (2.2) was lower than Parata (3.1) and AC Splendor (3.1), but similar to Glenn. The test weight of Jake (80.8) was higher than AC Splendor (78.3), similar to Parata (80.5), but lower than Glenn (82.5). The grain weight of Jake (35.6 g) was similar to Parata (35.6 g), but lower than Glenn (36.7 g) and AC Splendor (37.4 g), while the NIR Protein of Jake (15.9%) was higher than Glenn (15.5%) and similar to the other checks. Jake was moderately resistant to resistant to leaf, stem, and stripe rusts, and moderately resistant to common bunt during the 3 yr of testing. The reaction of Jake to Fusarium head blight was variable and ranged from moderately susceptible to moderately resistant, with DON values similar to Carberry and Glenn. Three years of end-use quality evaluation has indicated that Jake is acceptable for the CWRS class.