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HS-182 and HS-183 are food-grade soybean lines [Glycine max (L.) Merr.] with distinct seed protein profiles and food processing quality. HS-182 is a 7S β-conglycinin α’ and 11S glycinin A4 null with a high protein concentration of 45.7% and good processing quality. HS-183 is a 7S β-conglycinin α’ and 11S glycinin null with a protein concentration of 42.7% and poor tofu processing quality. They are adapted to areas of southwestern Ontario with 3100 or more crop heat units and have relative maturity groups of 2.5 and 2.4, respectively.

AAC Big Ben is a high yielding, soybean cyst nematode resistant food-grade soybean [Glycine max (L.) Merr.] cultivar with yellow hilum and acceptable processing quality for foreign and domestic tofu, soymilk, and miso markets. AAC Big Ben was developed at the Agriculture and Agri-Food Canada (AAFC) Harrow Research and Development Centre (Harrow-RDC), Harrow, ON. AAC Big Ben is adapted to areas of southwestern Ontario with 3300 or more crop heat units and has a relative maturity group of 2.3 (MG 2.3).

AAC Wigle is a high yielding, high-protein, large-seeded, soybean cyst nematode resistant food-grade soybean [Glycine max (L.) Merr.] cultivar with yellow hilum and acceptable processing quality for foreign and domestic tofu, soymilk, and miso markets. It was developed at the Agriculture and Agri-Food Canada (AAFC) Harrow Research and Development Centre (Harrow-RDC), Harrow, ON. AAC Wigle is adapted to areas of southwestern Ontario with 3200 or more crop heat units and has a relative maturity of 2.2 (MG 2.2) and protein content of 45.8%.

Soybean (Glycine max [L.] Merr.) is a major isoflavone producing legume. Isoflavones and their derivatives function as phytoalexins that may function in protecting plants against pathogens. They are also known as phytoestrogens in the human diet, which have putative positive human health effects such as reduced risk of breast and prostate cancers, cardiovascular disease, and high blood cholesterol levels. Therefore, increasing isoflavone concentration could be a desirable target for developing added value for food-grade soybean cultivars. Soybean cyst nematode (SCN; Heterodera glycines) is the most yield-limiting pathogen for soybean world-wide. The objectives of this study were to: 1) determine genotype (G) and genotype-by-environment (GE) interaction variation for seed isoflavone concentration and, 2) determine the effects that SCN resistance may have on seed isoflavone concentration in SCN infested and non-infested environments. A population of 109 recombinant inbred lines (RILs), derived from a cross between DH4202 and RCAT1004, along with 11 commercial check cultivars were grown in two SCN infested and two non-infested fields in southern Ontario, Canada, in 2015 and 2016. The genotypes were categorized into resistant, moderately resistant, and susceptible lines based on SCN female indices calculated from SCN infested environments. Significant G, environment (E), and GE interaction effects were observed for total isoflavone concentration as well as for yield. Higher isoflavone concentrations were observed in non-infested environments when compared with SCN infested environments for all three levels of resistance. Within SCN infested environments, resistant genotypes had significantly higher isoflavone concentrations than susceptible genotypes, indicating a potential role of isoflavones in plant defense from SCN in resistant genotypes. SCN infested environments were found to be more reliable for genotype evaluation of isoflavone concentration than non-infested environments due to similar relative performance of genotypes in all SCN infested environments. A strong relationship between the level of SCN resistance and relative yield among the genotypes was observed in SCN environments. When evaluating genotypes, soybean breeders should consider the negative impact SCN has on seed isoflavone concentration, the positive relationship between SCN resistance and isoflavone concentration in SCN environments, as well as the greater stability in isoflavone concentration across genotypes within SCN environments compared to the non-infested ones.

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).

To select dry bean ( Phaseolus vulgaris L.) vari- eties suitable for the canning and processing industry, it is essential to understand the genetic and environmental effects on the quality param - eters as well as their associations. A dataset of 6 yr of dry bean quality evaluations in the multi- location provincial registration trials in o ntario, Canada, with data for parameters routinely used by breeding programs to predict the final can ning quality of breeding materials was used. Genetic, environmental, and genotype (G) × environmental effects and multi-variable asso - ciations were studied using the estimates of the genotypic least squared means for the balanced yearly data and the best linear unbiased predic - tors (BLUps) for the overall unbalanced data. Genetic effects, accounting for 35 to 76% of the variation in navy bean and 38 to 88% of the vari - ation in large-seeded bean, followed by location (L) effects, accounting for 11 to 66% of the varia - tion in navy bean and 11 to 64% of the variation in large-seeded bean, were more important than the genotypelocation (GL) interaction effects for seed composition parameters. This was not the case for physical and texture parameters, where GL interaction effects were often most important. p associations were observed among hydration coefficient, can yield, and pro - tein content in the yearly analyses as well as in the multi-year analysis. The negative association between percent washed-drain solids and bean texture after processing was also repeatedly observed over years. The associations reported here may guide further selection efforts in bean breeding programs.

HS-151 is a lipoxygenase free food grade soybean line (Glycine max. L.) with large seed size, high protein content, yellow hilum, and satisfactory food processing quality. It is adapted to areas of southwest Ontario with 3100 or more crop heat units and has a relative maturity of 2.2 (MG 2.2).

Although soy proteins are known to have a deleterious effect on gluten thermosetting gelation, the causes are still poorly understood. Different sources of soy protein isolates (SPI) were used to investigate the interactions between gluten and soy proteins during hydro-thermal treatments. Commercial SPI and isolates prepared from soybean lines with different subunit composition were used to study the influence of protein denaturation and subunit composition on thermoset gel formation. Rapid Visco Analyser analysis showed that replacement of gluten with more than 1% SPI decreased the peak viscosity and interfered with formation of thermoset gels. However, peak viscosity was higher for 11% gluten + 2% SPI than for 11% gluten alone, suggesting a cooperative effect. After heating and cooling, 11% gluten + 2% SPI rich in A1 and A2 subunits formed a coherent thermoset gel suggesting that the cysteine residue content of soy proteins can affect gel formation.

Future soybean [Glycine max (L.) Merr.] cultivars with elevated or reduced concentrations of isoflavones may be required to satisfy the food market. Climate influences isoflavone concentration making their prediction problematic. Our research examined the associations between precipitation and temperature during a growing season with the isoflavone concentration in the harvested seed. We grew 14 cultivars across 12 years, at one location and calculated climate parameters for readily identifiable growth stage intervals (GSI). We correlated the climate parameters within each GSI with seed daidzein, genistein and total isoflavone (TIF) concentrations. We found that cumulative precipitation from the mid-vegetative to the flowering period was correlated with daidzein and TIF concentration. Mean daily average T during early vegetative development was positively correlated with daidzein and TIF concentration and this was largely a result of higher minimum daily T. Accumulated heat stress T greater than 27 °C during seed development was significantly correlated with a reduction in genistein and TIF, but not daidzein concentration. Accumulated cold stress T's less than 20, 15 and 17 °C during seedling emergence were significantly correlated with higher seed daidzein, genistein and TIF concentrations, respectively in all short-season cultivars tested. Cold stress T during seedling emergence could be used to predict seasonal changes in isoflavone concentrations.

The influence of soy protein subunit composition on the particle size distribution and solid content of soymilk and various supernatant fractions was investigated. A well-established seed variety (Harovinton), containing all protein subunits, and eleven null soybean genotypes lacking specific glycinin and β-conglycinin subunits were investigated, to determine the effect of protein composition on the physico-chemical characteristic of soymilk. Soymilk made from Harovinton and soybean lines null in glycinin showed significantly higher total solid yields than the other genotypes evaluated. Soymilks prepared from soybeans null for glycinin or lacking glycinin's group I (A 1 , A 2 ) showed a smaller particle size distribution compared to soybean lines containing glycinin. In general, unheated soymilk made from lines having glycinin showed a bimodal size distribution with large particles, with a decrease in the particle size distribution after heating and heating with homogenization. The results of this work will help in the evaluation of breeding lines with a specific protein composition tailored to a specific processing functionality.

Soy protein isolates (SPI) were prepared from 12 soybean lines grown in Harrow, Ontario and by-products (fibers and wheys) from SPI making were saved. The identification and quantification of soluble sugars in defatted flours, fibers and wheys were carried out using high-performance anion-exchange chromatography coupled with pulsed amperometric detection (HPAEC-PAD) and with a colorimetric method for uronic acids. Defatted flours and fibers were acid hydrolyzed, then analyzed by HPAEC-PAD for monosaccharide composition. The results showed varietal differences in the carbohydrate composition suggesting different applications for these defatted flours and their SPI by-products.

This study focussed on the evaluation of thermal denaturation at three different stages during soy protein isolation and the effect of subunit composition on the formation of heat-induced soy protein gels. Soy protein isolates (SPI) were prepared from 12 high protein lines, Harovinton variety and 11 derived null-lines which lacked specific glycinin (11S) and β-conglycinin (7S) protein subunits. Protein denaturation during SPI processing was monitored by differential scanning calorimetry (DSC). The results showed that hexane extraction of oil from soybean flours at 23 °C or 105 °C did cause changes in protein conformation. Rheological measurements showed that lines with different subunit compositions and 11S:7S ratio had distinctive gelation temperatures and resulted in gels with different network structures. All lines formed particulate gels at 11% protein. The 11S:7S ratio was not correlated to final stiffness, measured as the storage modulus G′, of SPI gels. Lower gelation temperatures were usually observed for 7S-rich lines. The absence of A3 and the combination of A1, A2 and A4 subunits of 11S fraction may suggest the formation of stiffer gels. A more detailed study of the frequency dependence of G′ for the various networks formed also indicated that differences in subunit composition influenced the network structures.

The effect of heat treatment at 95–100 °C for 5 min and homogenization on the physicochemical properties of soymilk was studied, determining the particle size distribution and the amount and type of protein present after step-wise centrifugation. Differential scanning calorimetry of soy protein showed three thermal transitions for unheated soymilk at 54, 70 and 94 °C, which were attributed to 2S, 7S and 11S, respectively. These thermal transitions were absent from heated (and homogenized) soymilk. Unheated soymilk showed a large average particle size, a broad size distribution, and significant protein precipitation with centrifugation. Heating of soymilk decreased the particle size distribution and improved its stability. Homogenization also resulted in a decrease in particle size, with a narrower size distribution compared to heated soymilk. During step-wise centrifugation changes in the ratios of 11S (glycinin) and 7S (β-conglycinin) in the supernatants were noted, and they depended on the treatments applied to soymilk. Transmission electron microscopy observations showed the distribution of the colloidal particles in soymilk and helped further identify the differences after heating and heating with homogenization.

Tofu was made, using two coagulants, from soybean lines which lacked specific glycinin and β-conglycinin protein subunits and the quality evaluated to determine the effects of specific protein subunits. The group IIb (A3) glycinin subunit played the major role in contributing to tofu firmness, regardless of coagulant, while the group IIa (A4) subunit had a negative effect on tofu quality in 2002. Soybeans with the group I (A1A2) subunit resulted in tofu with textural properties about one-third higher, expressed as a percent of Harovinton’s values, than tofu prepared from soybeans without the group I subunit. The individual components of group I had contradictory effects on GDL tofu quality in 2002, with the A1 subunit having a negative effect and A2 having a major positive effect. Lack of the α′ subunit of β-conglycinin increased gel hardness relative to the complete 7S protein.

1. This study evaluated the effect of dispersal on the density and feeding impact of a phytophagous insect in relation to the spatial distribution of its host plants. 2. The interaction between density, dispersal, and feeding impact of western flower thrips on flowering chrysanthemum was quantified at three spatial scales, with infested and uninfested plants either isolated in 0.25 m2 individual cages, or enclosed together in 2.25 m2 communal cages or 75 m2 greenhouses. 3. In individual cages, the rate of dispersal from chrysanthemum plants to blue sticky traps increased with the density of thrips for females but not males. Uninfested plants consistently had fewer thrips when they were individually caged rather than enclosed with plants infested with adults, indicating that dispersal mediates inter-plant distribution of thrips. 4. The feeding impact of thrips on inflorescences was evaluated using the absorbance of ethanol extracts at wavelengths characteristic of yellow carotenoid pigments associated with chrysanthemum inflorescences (415, 445, and 472 nm). Increasing absorbance of extracts with increasing density of thrips per inflorescence suggests that feeding by thrips results in ruptured cells leaching carotenoid pigments. 5. In communal cages, the distribution of thrips was uniform for infested and uninfested plants, whereas the density and feeding impact of thrips in greenhouses were higher for infested than uninfested plants. These results suggest that short-range dispersal by adults homogenises the density and feeding impact of thrips among host plants only on a small spatial scale.

Soymilk was made from 10 soybean [Glycine max (L.) Merr.] lines grown at three locations for 2 years, using an 18:1 water/soy protein ratio. Tofu was made with either glucono-delta-lactone (GDL) or calcium sulphate dihydrate (CS). Genotype and year effects were substantially greater than location effects on soybean protein content and seed composition; soymilk and tofu yield, solids levels, and pH; and tofu colour, hardness, and firmness. Genotype by location and genotype by year interaction effects were minor relative to the genotype and year effects. Yield of soymilk, GDL tofu, and CS tofu, which averaged 7.39 l, 6.29 kg, and 6.15 kg per kg soybeans, respectively, were all positively correlated with seed protein and stachyose, and negatively correlated with seed oil, free sugar, sucrose and remainder content. Seed protein was positively correlated with tofu hardness and firmness, while seed oil, free sugar, sucrose, and remainder content were generally negatively correlated with tofu quality parameters. Results of stepwise regression analysis showed that seed protein was the major determinant of soymilk yield and solids content, while soymilk yield was, in turn, the major factor determining GDL tofu yield. Procedures used in making soymilk and tofu play a major role in determining which seed component has a major effect on soymilk and tofu yield and quality.

The effects of long-term and transient exposure to elevated CO 2 concentrations on photosynthetic gas exchange and ethylene release by tomato leaves were investigated. The net CO 2 assimilation rate was enhanced when leaf tissue grown at ambient (35 Pa CO 2 ) levels was assayed at 100 Pa CO 2 . Leaf tissue grown at high (130 Pa) CO 2 exhibited a lower net CO 2 assimilation rate at high CO 2 levels than leaf tissue grown at ambient (35 Pa) CO 2 . This decrease in CO 2 exchange rate in response to growth at high CO 2 is typical of C 3 species

Soybean (Glycine max (L.) Merr.) seeds vary in their surface properties. The lustre, or glossiness, of seeds has been classified into several different phenotypes. Soybean seeds that have a dull lustre or moderate bloom (B) may also have abundant seed surface protein, namely, an abundance of the hydrophobic protein from soybean (HPS). The seed surface protein HPS is an allergen (Gly m 1) that causes asthma in persons allergic to soybean dust. In this study, seed lustre and surface protein content are compared among 71 different soybean cultivars and lines. Dull-seeded phenotypes usually possessed abundant surface protein in comparison to shiny-seeded types, although exceptions were observed. An F2population of 82 individuals from a cross of OX281 (dull lustre, abundant HPS) and Mukden (shiny lustre, trace amounts of HPS) provided a basis for inheritance studies and genetic mapping analysis. Results indicate that dull seed lustre (B) and surface protein (Hps) loci are dominant Mendelian traits that cosegregate and map to soybean linkage group E. Molecular markers were used to construct a genetic map of 28 cM encompassing B and Hps. Two different molecular markers cosegregated with each of the loci. This study provides additional evidence that Hps may play a role in the adhesion of endocarp tissues to the seed, and offers new methods of selection for seed lustre and surface protein composition in soybean.Key words: adhesion, allergen, hydrophobic protein, pericarp, seed coat.