Lecture 4 - Legume Introduction Flashcards
(20 cards)
legume family
Fabaceae
5 grassland functional groups
grasses, grass-like plants, forbs, shrubs, and succulents
structure of legume leaves
- most have compound leaves (highly variable)
- Often have stipules
structure of legume stems
-highly variable among species
-hollow or solid stems
structure of legume inflorescence
arrangement and number of florets vary
pollination types of legumes
-insect pollinated (most forage legumes)
-self-pollinated (most annual legumes)
parts of a typical legume flower
standard petal, 2 wing petals, keel (2 fused petals), sepal
type of root in legumes
often prominent taproot/storage organ
Description of legume seed
- single seed or single row of seeds per pod
-hard seed (sometimes not permeable to water) - will dehisce for natural seed dispersal
what may need to be done to legume seeds to insure rapid germination
scarification
how to tell if legume nodules are working
-large nodules
-red/pink in color if working (will be white, grey, or green if they are young or not working)
rhizobium/bacterium is ______ to legume
specific
what is the optimum conditions for rhizobium/bacterium
25-30C
soil pH 6.6-7.5
need legumes to be present in pop every couple years
when should you apply bacteria inoculum
to seed when establishing new stand
Inoculant types
peat-based inoculates (stick to seed)
granular inoculants (directly to soil)
what kind of inoculants must be refrigerated prior to use
peat-based inoculants
t/f: annuals fix more N than perennials
f, perennials fix more
when do perennial stands fix the most N
In year
under higher soil temp
in low soil N conditions
how does harvest effect the quantity of N fixed in a perennial population
initial reduction in N fixation
N fixation proves ______% of total plant requirement
30-95%
