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Hazelnut (Corylus avellana L.) is a monoecious, dichogamous plant species that flowers in winter and early spring. In traditional hazelnut growing regions, hazelnut cultivars generally express protandry where the male flowers bloom before the female flowers. Nut set requires that compatible pollen be shed when the stigmas of the main cultivar are receptive. In this study, the floral phenology and date of leaf budbreak of five selections and 19 hazelnut cultivars from Europe and North America were observed over 4 yr in southern Ontario, and results were compared with cumulative growing degree days (GDD). In the continental climate of southern Ontario, most cultivars showed protogyny. Flowering dates varied over the years with pollination occurring in a period of 2–3 wk in early spring. These cultivars were classified into early, mid, and late blooming types. A GDD model was a better tool than average daily temperatures to predict the flowering dates of catkins and female flowers. Averaged over years, most of the cultivars in this study have a female bloom that is likely too early for the pollen shed by most of the other cultivars. This would likely impact yields in a commercial orchard. However, ‘Jefferson’, ‘Gene’, and ‘Epsilon’ have late females that are receptive when other cultivars are shedding pollen.

Rapid multiplication of turmeric (Curcuma longa) by micropropagation is needed to produce a continuous source of uniformly sized, high-quality, and disease-free plantlets. Three in vitro experiments were conducted to optimize the medium by evaluating nine media and a full factorial combination (matrix) of two plant growth regulators for direct organogenesis of ‘Hawaiian Red’ turmeric. Two experiments evaluated the media, and the third studied the plant growth regulator matrix. As a result, Driver and Kuniyuki walnut (DKW), Murashige and Skoog (MS), and broadleaf tree basal (BLT) media performed better than woody plant media [Lloyd & McCown woody plant basal medium (L&M), and McCown’s woody plant basal salt mixture (McCown)] for shoot and root formation. The multiplication rate was 18 plants per explant in DKW with 1 mg⋅L−1 6-benzylaminopurine (BAP) and 0.1 mg⋅L−1 1-naphthaleneacetic acid (NAA). After transferring the plants to an ex vitro environment, the survival rate was 97%, and 30% higher than previously reported. DKW produced the highest number of plantlets (with shoots and roots), and BLT produced fewer plants with higher biomass. In the MS media, higher BAP to NAA ratio (2.5 to 0.1 mg⋅L−1) produced the most significant number of shoots; however, the lowest concentration of BAP and NAA (0.1 mg⋅L−1 of both) produced the highest number of rooted plantlets. There are two recommendations for tissue culture of ‘Hawaiian Red’ turmeric. To produce the highest number of plantlets, one should use the higher BAP to NAA ratio (2.5 mg⋅L−1 BAP and 0.1 mg⋅L−1 NAA) for shoot proliferation and then transfer the explants to the root initiation media. However, to reduce the number of subcultures, the explants can be grown in the lowest concentration of both BAP and NAA (0.1 mg⋅L−1) to induce both shoot and root. Although, the number of plantlets (with roots and shoots) will decrease in this method, there is no need for subsequent subcultures and changing of the plant growth regulator combinations.

In recent years, new vineyards have been established in southwestern Ontario. The open water of Lake Erie provides some winter protection for Vitis hybrids and winter-hardy Vitis vinifera L. cultivars in this area. However, winter damage is possible when vines are grown distant from the open water or when lakes are frozen. To better understand the risks to winter survival, the dormancy and chilling phenology were studied over three winters from 2013–2016. Ten dormant canes of two V. vinifera cultivars, ‘Chardonnay’ and ‘Riesling’, were collected weekly from 1 September until 30 March from the mature vines in a commercial vineyard located at St. Williams (Ontario). The canes defoliated in early October, and the endodormancy was completed by the end of December. The cumulative chilling hours (0–7.2 °C) from defoliation until the completion of endodormancy were averaged 606 hours for ‘Chardonnay’ and 665 hours for ‘Riesling’. ‘Chardonnay’ buds were slightly less hardy than ‘Riesling’ to cold temperatures, with a threshold of about −24 °C for ‘Chardonnay’ and −25 °C for ‘Riesling’. Most primary buds of both cultivars died after 16 February 2015, and more than half died after 12 February 2014, due to severe low temperatures of −33.1 and −26 °C, respectively.

The global demand for hazelnuts is increasing steadily, driven by increasing use by chocolate companies, pharmaceuticals, health products, and others. North America only produces 5% of the world crop, of which 99% is produced in Oregon (OR, USA). Most available cultivars are adapted to areas with mild winters and thus do not perform well in Ontario (ON, Canada). Our objective was to identify genotypes capable of supporting the newly formed hazelnut industry in southern Ontario. In the last several decades, selections have been identified in ON, New York (NY, USA), and Michigan (MI, USA) that may be better adapted in ON than cultivars from Europe and OR. To test our hypothesis that these new selections would outperform cultivars from Europe and OR in southern Ontario, two trials were performed to evaluate yield, nut quality, and winter hardiness. As hypothesized, selections from ON and NY such as ‘Gene’, ‘Alex’, and ‘Slate’ were winter hardy and highest yielding, followed by ‘Butler’ and ‘Gamma’ from OR; however, these selections did not perform well in other assessed parameters such as nut quality and catkin survivability. Possible explanations for the poor performance of the European and OR cultivars include (i) longer time needed to acclimatize and enter production phase relative to selections from ON, NY, and MI, and (ii) cold susceptibility during the initial establishment phase. The need to allocate resources towards survival probably delays the ability of the European and OR cultivars to enter the production phase. In conclusion, hazelnut cultivars brought from regions with a different climate need to be tested for cold hardiness.

Anthocyanins are a group of water-soluble polyphenolic pigments found primarily in flowers, vegetables, and fruits. These pigments play critical roles in plant and human health. Spectrophotometric methods are a simple and inexpensive way to quantify anthocyanins in plant tissues. Two main spectrophotometric methods have been developed, organic solvent-based, and pH differential methods. Both of these methods are subject to interference from light-absorbing impurities and need to be optimized for different matrixes of different plant materials. Eight methods have been tested in this experiment to quantify anthocyanins in strawberry fruits. Six organic solvent-based methods tested methanol, chloroform-methanol, and MgO in different ratios. The other two methods were pH differential method and a combination of organic solvent-based and pH differential method. Two methods used organic solvents (methanol and chloroform-methanol) were the best in extracting anthocyanin from strawberry fruits. Adding MgO increased the pH of the extract and was less efficient in anthocyanin extraction. All other methods had lower anthocyanin yield compared with methanol and chloroform-methanol methods and are not recommended for strawberry fruit anthocyanin extraction.

Common strawberry cultivars are hermaphrodites, producing both anthers and pistils in their flowers. However, octoploid Fragaria species are trioecious and different genotypes can be female with pi...

The strawberry production season can be extended in Ontario if plantings are protected from adverse weather conditions. At present, dayneutral cultivars developed in California are used for product...

Small fruits are a multi-billion dollar industry in the US, and are economically important in many other countries. However, they are perishable and susceptible to physiological disorders and biological damage. Food safety and fruit quality are the major concerns of the food chain from farm to consumer, especially with increasing regulations in recent years. At present, the industry depends on pesticides and fungicides to control food spoilage organisms. However, due to consumer concerns and increasing demand for safer produce, efforts are being made to identify eco-friendly compounds that can extend the shelf life of small fruits. Most volatiles and essential oils produced by plants are safe for humans and the environment, and lots of research has been conducted to test the in vitro efficacy of single-compound volatiles or multi-compound essential oils on various microorganisms. However, there are not many reports on their in vivo (in storage) and In situ (in the field) applications. In this review, we discuss the efficacy, minimum inhibitory concentrations, and mechanisms of action of volatiles and essential oils that control microorganisms (bacteria and fungi) on small fruits such as strawberries, raspberries, blueberries, blackberries, and grapes under the three conditions.

Almond and its related wild species, which are widely distributed in Central and West Asia, have high genetic variation. This is an important source of genetic diversity for crop improvement. In this study a set of 32 SSR and 12 EST-SSR primer pairs were used to determine genetic diversity in 89 accessions of almond and other Prunus species. Most of the accessions (68) were collected from natural habitats of Iran. SSR primers amplified higher numbers of alleles than EST-SSR markers and discriminated genotypes more effectively. Results indicated high diversity among accessions. Observed heterozygosity (Ho) was 0.581. Nei’s index of diversity (He) and average number of alleles per locus (na) were 0.885 and 34, respectively. The mean value of polymorphism information content (PIC) was 0.874. The average Fst (F-statistics index) was 0.271 and the fixation index (Fis) was 0.151. Estimated variance among putative populations (AP) and individuals (AI) and within individuals (WI) were 5, 35, and 60%, respectively, which revealed that most of the variation was distributed among individuals rather than groups. Cultivated almonds were highly similar to P. fenzeliana, which is native to West Asia, supporting the importance of these regions in almond domestication. In the dendrogram of groups, minimum genetic distance was observed between Amygdalus and Orientalis groups from the Euamygdalus section. The Leptopus and Chameamygdalus sections were more distant from almonds than plums. The results also showed Dodecandra (Lycioides) series should be taxonomically classified closer to the section Euamygdalus.

Wild almond species are important genetic resources for resistance to unsuitable condition, especially drought stress. They have been used traditionally as rootstocks in some areas of Iran. So far, 21 wild almond species and 7 inter species hybrids have been identified in Iran. To study seed germination and seedling establishment of some of these species, three separate experiments were designed. In the first experiment, the application of gibberellic acid (GA 3 ) (0, 250, 500 and 750 ppm) for 24 h was studied on germination characteristics of four wild almond accessions after stratification at 5 ± 0.5°C in Perlite media. Germination percentage, index vigor and root initiation factors were different in almond accessions, but were not affected by hormonal treatments. In the second experiment, seeds of another six wild almond accessions were stratified to compare their germination ability. Germination percentage, index vigor and root initiation were different among accessions significantly. In the last experiment, the establishment and vigor of 14 accessions from eight almond species have been evaluated in plastic bags in outdoor conditions. Two ecotypes of Prunus spp. had the highest stem diameter and length at all growing stages. Keywords: Amygdalus, germination percentage, index vigor, root initiation, stem length, stem diameter.

Vitis riparia (Michaux) is native to North America and tolerates the local weather and soil conditions of south-western Ontario in Canada. A survey was done on V. riparia to elicit the distribution of pests on the species in central south-western Ontario. Eight hundred and forty four genotypes of V. riparia were observed throughout the sandy soils of five counties in Ontario (Brant, Elgin, Middlesex, Norfolk and Oxford). The location of the selected vines was labeled in the Geographic Information System (GIS). The ArcGIS program was used to make maps of the distribution of the wild grape pests, Phylloxera, Japanese beetle, Filbert gallmaker, Cane Filbert gallmaker, Tumid Filbert gallmaker and Tube Filbert gallmaker midges in those areas. The results show that the density of pests on V. riparia is more severe in some areas than others. Phylloxera and Japanese beetle were the major pests observed. Phylloxera was most prevalent and Japanese beetle least prevalent in Elgin County. The gallmaker midges were found in low densities throughout the area. The distribution of Phylloxera could be related to the soil type, and the distribution of Japanese beetle and Tumid gall midge to the land use. With Phylloxera, it appears that they prefer poor drainage soils which do not dry out readily. Whereas, Japanese beetle and Tumid gall midge prefer undisturbed soils where they can overwinter successfully.