Research Notes : Canada : Flecked pigmentation of soybean seed coats

Genetic type T85 has black seed coats that are flecked with brown pigmentation. Flecking has been reported to be controlled by a single dominant gene, Fl (Woodworth in Morse and Cartter, 1937). This gene has been trans-ferred into \u27Clark\u27 by backcrossing (173-1004; R. L. Bernard, personal communication). Patterned seed coats have been observed in Glycine soja and G. gracilis (Stelly and Palmer, 1979)

Research Notes : Tolerance/resistance to soybean mosaic virus

A natural epiphytotic of soybean mosaic virus (SMV) occurred at the Harrow Station in 1976. The disease, which was noted in early July, reduced plant growth. Advanced lines from \u27Corsoy\u27 x \u27Chippewa 64\u27 were being tested in the field in relation to their flavonol glycoside classification. Plants were rated for severity of leaf symptoms and seeds were rated for mottling

Research Notes : Genetics of black pigmentation of soybean seedcoats/hila

Gene T is involved in black pigmentation and w1 in the presence of t is involved in imperfect black pigmentation (Bernard and Weiss, 1973). Tis a phenolase gene resulting in quercetin formation and brown pubescence (Buttery and Buzzell, 1973); W is a flower and hypocotyl-color gene (Hartwig and Hinson, 1962). Thin layer chromatography shows two major \u27spots\u27 involved in black pigmentation of soybean seed coats

Research Notes : Soybean linkage and crossover tests

A previous test (Buzzell, 1977) indicated a possible linkage (39.8 .±. 3.0%) between Fg1 and Dt1. An additional test with F2 plants of a cross of two \u27Harosoy\u27 isolines (fg1 dt1 x Fg1 Dt1) indicates that the two genes are independent (Table 1). In reporting on the genetics of flavonol classes 9T to 16T, Buzzell and Ruttery (1974) indicated that the 9t to 16t classes which involve fg4t had not been observed

Research Notes : Inheritance of presence/absence of flavonoid compounds in soybean seedcoats

In soybean plants carrying the gene T and having black or brown pigmentation of seed coats, there are numerous compounds that can be detected by thin layer chromatography (TLC). There are four spots (A, B, C and D) that appear to be related; they are yellow-orange under visible light and they fluoresce yellow-orange (duller than quercetin) under UV light after spray-ing with flavone reagent. Phenotypic positions of A and D on 2-way plates are given in Table 1. A is present in all material tested, but D varies in presence/absence (B and C also vary but have not been studied)

Research Notes : Soybean emergence in clay soil and tolerance to phytophthora rot

In 1979 at the Woodslee Soil Substation, 19 F2 populations were planted May 23 in single-row plots, 100 seeds per row, with 12 replications. These populations consisted of \u27Williams\u27 x \u27Wells\u27, and Williams and Wells each by \u27Adams\u27, \u27Beeson\u27, \u27Bonus\u27, \u27Galland\u27, \u27Corsoy\u27, \u27Cutler 71\u27, \u27Hark\u27, \u27Kanrich\u27 and \u27Prize\u27. The field had been in continuous soybeans since 1973 and is known to be infested predominantly with race 7 of Phytophthora mega-sperma f. sp. glycinea (Pmg)

Research Notes: Another major gene for resistance to Phytophthora megasperma var. sojae in soybeans

L62-904 has resistance (Table 1) to some races of Phytophthora megasperma var . sojae (Pms) . L62-904 was developed by Dr. R. L. Bernard at Urbana from Harosoy6 x T240; it was an F2 selection from an F1 - BC5 plant that was Ps ps W1 w1. It was used at Harrow as a w1w1 \u27Harosoy\u27 isoline with white flowers/green hypocotyls as a genetic marker in crosses before it was discovered to have Pms resistance

Research notes: Soybean parental lines

Seed of five improved breeding lines (Table 1) is available upon request for use in crosses or experimental work. Disease reactions are given in Table 2 and physiological attributes in Table 3. The lines are somewhat improved over the unadapted parents; however, only OX610I has been yield tested

Research Notes : Canada : Linkage tests

Results reported by Buzzell (1974) were not conclusive as to whether or not E3 (daylength response) and Ep (seedcoat peroxidase) are independent or loosely linked. Palmer et al. (1984) has shown that Ep is linked with Frl in linkage group 12. Using F2 plants of \u27Minsoy\u27 x \u27Hark\u27 previously reported (Palmer et al., 1984) for seedcoat peroxidase and root fluorescence, we tested for linkage of E3 with Ep and Frl by testing F3 material for response under a daylength extended to 20 h with cool white fluorescent light