Seeding date, row spacing, and weed effects on soybean isoflavone concentrations and other seed characteristics

2006 ◽  
Vol 86 (4) ◽  
pp. 1079-1087 ◽  
Author(s):  
A. M. Al-Tawaha ◽  
P. Seguin

Soybean [Glycine max (L.) Merr.] seeds contain isoflavones that may have positive impacts on human health. Field experiments were conducted in 2003/2004 in Québec, Canada to determine the effects of seeding date (late May and mid-June), row spacing (20-, 40- and 60-cm) and weeds (presence or absence) on soybean isoflavone concentrations and isoflavone yield. Total and individual isoflavone concentrations were determined by HPLC. Seed yield, and oil and crude protein (CP) concentrations were concurrently determined. Year, seeding date, and weeds affected total and individual isoflavone concentrations, while row spacing had no effect. Total isoflavone concentration was 84% greater in 2003 than 2004. Seeding in mid-June increased isoflavone concentration by 38%, compared with seed ing in May. The presence of weeds increased total isoflavone concentration by 9%. Year, row spacing, and weeds significantly affected seed yields. Seed yields were greatest in 2004, at 20- or 40-cm row spacing, and in the absence of weeds. Seeding date affected CP and oil concentrations. Greater CP concentration was observed with earlier seeding, the reverse was observed for oil. Weeds also affected CP and oil concentrations: higher CP and oil concentrations were observed in weedy and weed-free plots, respectively. Total isoflavone yield was affected by all factors evaluated. Isoflavone yield was greater in 2003 than 2004, with mid-June rather than late May seeding, when seeded at row spacing of 20- or 40- than 60-cm, and without weeds. Finally, negative correlations were observed between isoflavone concentrations and CP concentration and seed yield. It thus seems that certain agronomic practices may need to be tailored specifically to isoflavone production if concentrations in soybean are to be maximized. The negative correlations observed between isoflavone concentrations and other important seed characteristics warrant further research. Key words: Soybean, isoflavone, daidzein, genistein, glycitein, protein, oil, seed yield, weeds, row spacing, seeding date

1992 ◽  
Vol 38 (6) ◽  
pp. 588-593 ◽  
Author(s):  
D. J. Hume ◽  
D. H. Blair

In the absence of Bradyrhizobium japonicum populations in the soil, yields of field-grown soybean (Glycine max (L.) Merrill) usually respond to inoculation with B. japonicum. The objective of this research was to determine the relationship between numbers of B. japonicum per seed in inoculants and soybean nodulation and yield. A total of six field experiments were conducted in 1989 and 1990 on new soybean soils. In dilution trials, Grip inoculant was applied to provide approximately 106, 105, 104, and 103B. japonicum per seed at two locations in 1989. Nodule number and mass, as well as seed yield, increased curvilinearly upward with increasing log10 most probable numbers (MPNs) of B. japonicum. The yield response curve was best fit by a cubic equation, which accounted for 97% of the variation in yield. Seed yields increased 19% (1.83 to 2.13 Mg/ha) from 105 to 106B. japonicum per seed. In field experiments involving 8 commercial inoculants in 1989 and 10 in 1990, and conducted at two locations in each year, responses to increasing log MPNs in the inoculants also were concave upwards and cubic. In the two years, 78 and 46% of the yield variation was accounted for by log MPN per seed. Increasing MPN per seed from 105 to 106 improved yields in first-time fields by an average of 24%, indicating the present minimum standard of 105B. japonicum per seed should be increased. Key words: most probable numbers, response to inoculation, nodulation, Glycine max (L.) Merrill.


1983 ◽  
Vol 100 (2) ◽  
pp. 285-292 ◽  
Author(s):  
T. O. Tayo

SUMMARYThe size of the sink on two indeterminate (cv. Hampton and cv. TGM 119) and two determinate (cv. Bossier and cv. TGM 294) cultivars of soya beans were reduced by continuously limiting the number of pods developing at each fruiting node to either one or two, starting from 2 weeks after anthesis, in three field experiments (early 1980, late 1980 and early 1981). Thiswas in order to evaluate the effects of sink size on the development of pod and seed characteristics as well as to quantify the inter-relationships between these characters under humid tropical conditions.Persistently reducing the number of pods developing at each fruiting node consistently significantly reduced the number of pods per plant, the pod and seed dry weights per plant, the total number of seeds per plant and the harvest index (seed weight as a proportion of total dry weight) in all cultivars when compared with the control. On the other hand, the treated plants of all cultivars generally had longer pods, heavier individual pods and seeds, more seeds per podand greater leaf area and leaf dry weight as well as greater specific leaf weight than the control plants. Compensation indices (percentage increases in size over control) were 25–30% for weight per pod and seed weight per pod; 11–16% for weight per seed and number of seeds per pod and 2–5% for pod length in the treated plants.Most of the characters measured (except individual weight of pods and seeds, seed weight per pod and number of seeds per pod) had significant interaction effects of sink size, cultivar and season; season had the highest correlation ratio, followed by cultivar, and sink size had the least. Also, nearly all components of seed yield were positively highly significantly correlated with one another; the number of seeds per pod and the number of pods per plant accounted for 76% of the variation in seed dry weight per plant.It would seem therefore that under the prevailing humid tropical conditions, the most important component of seed yield in soya bean is the number of seeds per pod, as affected by the sink size.


1977 ◽  
Vol 88 (1) ◽  
pp. 151-157 ◽  
Author(s):  
T. O. Tayo

SUMMARYThe growth, development and yield of three soya-bean varieties, Hampton, Kent and CNS, were compared in two field experiments during 1974 and 1975 in Nigeria. The results, which were similar for both years, showed that the varieties differed significantly in the order Hampton > Kent > CNS for the development per plant of leaf area, number of branches, number of nodes, number of mature pods, number of seeds, pod and seed yields, husk dry weight and seed to husk ratio as well as seed yield per hectare. The differences between the varieties in seed yield could be genetic but leaf area development seems important as well. Hampton therefore appears to have the potential for high seed yield under the prevailing local conditions.


2006 ◽  
Vol 86 (3) ◽  
pp. 677-684 ◽  
Author(s):  
A. M. Al-Tawaha ◽  
P. Seguin ◽  
D. L. Smith ◽  
C. Beaulieu

Soybean [Glycine max (L.) Merr.] is a key species used by the nutraceutical industry, as it contains isoflavones that have beneficial effects on human health. A 2-yr field study was conducted in Sainte-Anne-de-Bellevue, QC, to determine the effects of foliar application of elicitor compounds on isoflavone concentrations of seeds, seed yield, and other important seed characteristics. Two soybean cultivars (AC Proteina and AC Orford) were treated with one of four elicitors: lipo-chitooligosaccharides (LCO) Bj V (C18:1 MeFuc) and Bj V (Ac, C16, MeFuc), chitosan, and actinomycetes spores (Streptomyces melanosporofaciens strain EF-76), each applied at two soybean stages of development [vegetative (V4), and early podding (R3)]. Untreated controls were also included. Total and individual isoflavone concentrations were determined by HPLC. Seed yield, 100-seed weight, seeds per pod, pods per plant and oil and crude protein concentrations were concurrently determined. Total and individual isoflavone concentrations were affected by year and cultivar, which also interacted with elicitors. Interactions indicated that plant response to elicitors varied greatly depending on cultivars and years. Compared with an untreated control, some elicitors resulted in total isoflavone concentration increases ranging between 67 and 87%. No single elicitor treatment, however, consistently increased isoflavone concentrations. There were three-way interactions (year, cultivar and elicitors) for seed yield and number of pods per plants indicating, again, substantial variation in response to elicitors. Response was much greater in 2004, where elicitors consistently increased seed yield and number of pods per plant. Elicitors did not affect crude protein and oil concentrations. The use of elicitor compounds seems promising as a means of increasing isoflavone concentrations and seed yield; evaluations in a greater number of environments are now required. Key words: Soybean, isoflavone, daidzein, genistein, glycitein, protein, oil, seed yield, chitosan, actinomycetes, lipo-chitooligosaccharides


2012 ◽  
Vol 92 (1) ◽  
pp. 97-107
Author(s):  
Juliana J. Soroka ◽  
Larry F. Grenkow

Soroka, J. J. and L. F. Grenkow. 2012. When is fall feeding by flea beetles ( Phyllotreta spp., Coleoptera: Chrysomelidae) on canola ( Brassica napus L.) a problem? Can. J. Plant Sci. 92: 97–107. Two cultivars of Brassica napus canola were seeded in mid-May and early June in three field experiments in each of 3 yr near Saskatoon, Saskatchewan, to determine the effects of late-season flea beetle feeding on seed yields. In the first experiment, canola was sprayed with insecticide late in the summer to eliminate naturally-infesting flea beetles. In the second, 1×1×1.5 m screen cages were placed over early- and late-seeded canola at flowering and infested with flea beetles as canola matured. In the third investigation, sleeve cages were placed over individual plants and infested with 100 flea beetles. Flea beetles had no detrimental effects on early-seeded canola in any experiment, but did affect seed yields of late-seeded plots in some trials. Over two cultivars in 1 year, late-seeded plants in cube cages infested with about 350 flea beetles per plant when lower pods were turning from translucent to green in colour reduced yield by 241 kg ha−1 over control yields. Seed weights in these late-seeded plots were decreased from 2.68 g per 1000 seeds in uninfested cages to 2.44 g per 1000 seeds in infested cages. Populations of 100 flea beetles per plant in sleeve cages had no effect on harvest parameters in any seeding date or year.


1991 ◽  
Vol 5 (4) ◽  
pp. 707-712 ◽  
Author(s):  
Jeffrey A. Koscelny ◽  
Thomas F. Peeper ◽  
John B. Solie ◽  
Stanley G. Solomon

Field experiments were conducted in Oklahoma to determine the effects of winter wheat seeding date and cheat infestation level on cultural cheat control obtained by increasing winter wheat seeding rates and decreasing row spacing. Seeding rate and row spacing interactions influenced cheat density, biomass, or seed in harvested wheat (dockage) at two of three locations. Suppressive effects on cheat of increasing wheat seeding rates and reduced row spacings were greater in wheat seeded in September than later. At two other locations, increasing seeding rate from 67 to 101 kg ha–1or reducing row spacings from 22.5 to 15 cm increased winter wheat yield over a range of cheat infestation levels.


Agronomy ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 136 ◽  
Author(s):  
Samantha Grimes ◽  
Timothy Phillips ◽  
Filippo Capezzone ◽  
Simone Graeff-Hönninger

To obtain high chia seed yields and seed qualities, a suitable crop management system needs to be developed for the given growing conditions in southwestern Germany. Field experiments were conducted at the experimental station Ihinger Hof in two consecutive years (2016, 2017). The study aimed to evaluate yield and quality traits of chia depending on different (i) row spacing (35, 50 and 75 cm), (ii) sowing densities (1, 1.5 and 2 kg ha−1) and, (iii) N-fertilization rates (0, 20 and 40 kg N ha−1). It consisted of three independent, completely randomized field experiments with three replications. Results showed that chia seed yields ranged from 618.39 to 1171.33 kg ha−1 and that a thousand seed mass of 1.14 to 1.24 g could be obtained. Crude protein-, crude oil- and mucilage contents varied from 18.11–23.91%, 32.16–33.78% and 10.00–13.74%, respectively. Results indicated that the year of cultivation and the accompanied environmental conditions, like precipitation or temperature, influenced the determined traits more than the applied agronomic practices. As average seed yields exceeded those obtained in the countries of origin (Mexico, Guatemala) while having comparable quality characteristics, chia holds great potential as an alternative crop for farmers in southwestern Germany.


1978 ◽  
Vol 90 (2) ◽  
pp. 261-267 ◽  
Author(s):  
P. D. Hebblethwaite ◽  
A. Burbidge ◽  
D. Wright

SummaryThe effects of lodging on the seed yield of S. 23 and S. 24 perennial ryegrass were investigated in a series of field experiments from 1973 to 1976. Natural lodging severely reduced seed yield in all years as a result of a decrease in the number of seeds per unit area. Controlled lodging at different stages of crop growth produced more variable results, indicating that lodging may affect both pollination and seed development. Disturbance of the crop during anthesis in order to aid pollination did not improve seed yields, possibly as a result of damage incurred.


1996 ◽  
Vol 76 (2) ◽  
pp. 299-306 ◽  
Author(s):  
N. A. Fairey ◽  
L. P. Lefkovitch

The natural growth habit of creeping red fescue (Festuca rubra L. var. rubra) involves a steady proliferation of tillers which eventually become too dense to form seedheads. The effects of the initial density (1.6, 3.1, 6.3, 12.5, 25, 50 and 100 plants m−2) and row spacing (20, 40 and 80 cm) on reproductive components and seed characteristics of red fescue were studied in a northerly environment for three production years (1991–1993) The weight proportion of cleaned to uncleaned seed decreased as density increased, from 82% at 1.6 plants m−2 to 60% at 100 plants m−2. The thousand-seed weight was 1.20–1.54 g (i.e., 830 000–650 000 seeds kg−1) and decreased as density increased. The specific seed weight was 16–25 kg hL−1; it differed among years and decreased as density increased. The germination capacity of the seed was unaffected by density but differed among years, averaging 87, 92 and 69% in the three consecutive production years. The seed yield per plant, the number of seedheads per plant, and the number of seeds per plant decreased exponentially as the density increased. The number of seeds per seedhead decreased as density increased in the first year but was less affected subsequently, except in the third year at 50 and 100 plants m−2 on 20-cm rows, when no seeds were matured. The seed yield was correlated closely with the number of seedheads per square metre, which increased with density in the first year but decreased as density increased in the two subsequent years. A relatively high density of well-spaced plants is required at establishment to optimize seedhead formation in the first crop but is detrimental to seedhead formation and seed yield subsequently. Key words: Red fescue; Festuca rubra var. rubra, population density, plant and row spacing, yield components, seed quality


1977 ◽  
Vol 88 (3) ◽  
pp. 605-614 ◽  
Author(s):  
P. D. Hebblethwaite

SUMMARYThe effects of irrigation and nitrogen on S. 23 perennial ryegrass grown for seed were investigated in a series of field experiments from 1972 to 1974. Irrigation significantly increased seed yield by 16% in 1972 and 52% in 1974 but had no effect in the wet year of 1973. In 1972 maximum deficit reached 110 mm at the end of July and coincided with anthesis. Consequently the yield response was due to an increase in number of seeds per unit area and no other seed yield component was affected. In 1974 peak deficit also reached about 100 mm but started to build up rapidly very early in the season and had reached 80 mm by the time that the first ears emerged. Consequently the yield response was due to increases in number of fertile tillers, number of seeds per unit area and 1000-seed weight.Irrigation had no significant effect on number of florets or seeds, except in 1974 when percentage of florets which produced seed was increased by 2%.Irrigation had some effect on threshed straw yields, total dry matter, harvest index and total number of tillers but where this occurred the response was much smaller than that of seed yield which indicates that irrigation had greater effects on the reproductive development of the crop than on yield of dry matter and tillering patterns. Increasing the quantity of nitrogen from 0 to 80 kg/ha increased seed yields, all seed yield components except 1000-seed weight, threshed straw yields and total dry matter and number of tillers at most sampling dates. Increasing the quantity of nitrogen from 80 to 160 kg/ha had little further effect on the above components except in 1972 where seed yields were significantly decreased.In 1972 number of florets was increased and percentage of florets which produced seed decreased with increasing quantities of nitrogen.


Sign in / Sign up

Export Citation Format

Share Document