Crop agronomy Flashcards
what does allelopathy mean?
when an organism produces one or more biochemicals that influence the growth of plants around them.
Which crops are less susceptible to droughts?
Barley and oats due to early ripening making droughts irrelevant and triticale (edwin you batty crease)
Which crops can thrive in more acidic soils (pH 5.5)
Oats, rye and potatoes
Which crop grows better in soils with high salinity (salt)?
Barley (peas and beans are very sensitive)
what 2 crops are allelopathic?
rye
triticale
what temperature does rye germinate?
1 degrees
what temperature do oats germinate at?
3/4 degrees
what are two good point about triticale?
stress tolerant
more disease resistant than wheat
which crop isn’t very competitive with weeds?
barley
two good points about barley?
can handle highly saline soils
can tolerate higher temperatures
2 good points about rye?
germinates and grows in cold temperatures
most winter hardy grain
How do pests, weeds and pathogens develop resistance to pesticides? (2)
1) Under dosing of pesticides are non toxic (so plants and pests survive and breed to become resistant)
2) Incorrect application timings reduces effectiveness (due to weed vulnerability)
Name 4 ideal weed characteristics ?
- rapid development to reproductive phase
- seed dormancy
- persistent seed/propagule bank
- perennial: regeneration from fragments
What is biological nitrogen fixation (BNF)?
Atmospheric nitrogen is converted to ammonia by the bacterial enzyme nitrogenase (catalyzes the conversion of atmospheric nitrogen)
how long is the first approval period of a pesticide?
10 years
