Term
List the following for soybeans:
Scientific name
Family name
Origin
Major Producing Countries |
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Definition
Scientific name: Glycine max.
Family name: Leguminosae
Origin: Eastern Asia
Major producing countries: USA, Brazil and Argentina
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Term
| True or False - soybeans are diploids |
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Definition
| False. Proven now that soybeans are tetraploids with n=10 |
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Term
| In the early 1800's, what were soybeans produced for? |
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Definition
| In the US, soybeans were produced for soy sauce and were later used as a forage crop. |
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Term
| What are the technological developments that contributed to soybeans to become a major crop? |
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Definition
- Discovered that they could fix atmospheric nitrogen if roots were infected with Rhizobia
- Heating soybean meal caused trypsin inhibitors to be destroyed. Allowed for source of protein in livestock feed
- Found soybeans to be more drought tolerant than corn
- Found that daylength was important for soybean flowering - lead to devleopment in cultivar adaptation
- Shortage of fats and oils in WW2, so soybeans were used as a new source for vegetable oils (instead of just a forage crop)
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Term
| Why does adding fertilizer nitrogen to soybeans not cause an increase in soybean yield? |
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Definition
Soybeans are able to fix their own nitrogen with the help of Rhizobia bacteria
Adding extra N decreases nodulation and N2 fixation |
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Term
| Where was the first soybean production reported in Ontario? |
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Definition
Pelee Island, 1920's
production was constrained to SW Ontario (was part of North American corn belt) |
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Term
| Of what importance does the Japanese germplasm have to soybeans? |
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Definition
Allowed soybeans to be better adapted to higher lattitudes, cooler temperatures and shorter growing seasons
Soybeans could now be grown all over Ontario |
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Term
| Where in Canada does the most soybean production occur? |
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Definition
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Term
Explain the following statement:
"Flowering in most soybean varieties in photoperiod sensitive" |
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Definition
Soybeans are considered to be a short day plant, so they need long nights to flower
Since daylength varies with lattitude, the region for optimum growth of soybeans extends only a few hundred miles. Moving outside of this region results in too early/ tool late of flowering |
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Term
| In soybeans what is a maturity group? |
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Definition
A maturity group is a classification of a soybean variety
Maturity groups are determined using lattitude (different lattitude = different daylength)
North to South
00 (long day) to VIII (short day) |
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Term
| How are maturity groups used in the naming of most soybean varieties? |
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Definition
Included in the label for each variety
ex: a label stating "S03-W4" indicated maturity group 0.3 |
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Term
| Other than maturity groups, how else are soybean varieties classified? |
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Definition
| They are classified based on their Crop Heat Unit (CHU) rating |
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Term
| Compare and contrast Indeterminate and Determinate soybeans |
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Definition
Indeterminate
- Grown in Nothern US and Canada
- Flowering occurs earlier
- Overlap between vegetative and reproductive growth
- Lodging
Determinate
- Grown in Southern US (less of a risk of frost due to longer growing season)
- Resistence to lodging
- Reproductive and vegetative stages are very distinct
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Term
| What caused a huge expansion in soybeans for Brazil? |
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Definition
| Discovered that a "long-juvenile" gene could be inserted into soybeans that would hold the plant in a vegetative state until it was large enough to have good yields |
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Term
| List the Growth Stages of soybeans |
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Definition
V = indicates vegetative growth
VE = cotyledons are above the surface
VC = cotyledons have folded down and unifoliate leaves have expanded
V1-V6 = count from unifoliate and up to second highest leaf. NITROGEN FIXATION OCCURS AT V2 or V3
R = indicates reproductive growth
R1 = beginning bloom. First apperance of open flowers
R2 = full bloom. Flowering all throughout plant
R3 = beginning pod. First pods have appeared
R4 = full pod. At least 1 pod that is 2 cm long
R5 = beginning seed. At least 1 seed is 3mm
R6 = full seed. At least one pod has a green seed that fills pod cavity
R7 = beginning maturity. At least 1 pod has reach mature colour
R8 = Full maturity. 95% of pods have reached mature colour and most leaves have dropped from plant |
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Term
| What kind of marketplaces do soybeans grown in Ontario go to? |
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Definition
Oil extraction and soybean meal
Food grade soybeans |
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