C3 and C4 types of photosynthesis.

[Pilatus]

I was told a long time ago that Maize grows in a different way to most plants.
At long last I have found what the difference is ,Maize Uses C4 type photos synthesis compared to most other plants using C3 photosynthesis.
From what I can make out C4 photosynthesis is much better for taking up Carbon Dioxide.
It’s ok I am recovering from Hernia operation so plenty of time for finding out useless information!

 

[Bogweevil]

I was told a long time ago that Maize grows in a different way to most plants.
At long last I have found what the difference is ,Maize Uses C4 type photos synthesis compared to most other plants using C3 photosynthesis.
From what I can make out C4 photosynthesis is much better for taking up Carbon Dioxide.
It’s ok I am recovering from Hernia operation so plenty of time for finding out useless information!

Yes, c4 sort of pumps co2 into leaves as opposed to passive flow in c3 which loses more water as the stomata have to stay open longer. The downside is c4 enzymes are generally cold sensitive so only found in warm season crops.

Now that is settled, move on to CAM to see why cacti are even more water efficient than C4.

 

[Pilatus]

Yes, c4 sort of pumps co2 into leaves as opposed to passive flow in c3 which loses more water as the stomata have to stay open longer. The downside is c4 enzymes are generally cold sensitive so only found in warm season crops.

Now that is settled, move on to CAM to see why cacti are even more water efficient than C4.

Bogweevil, thanks for taking the time to reply.
Interesting info,I wonder if plant scientists have/ are trying to produce strains of wheat etc that need less moisture to grow to reach full maturity , a form of C4 cereal.

 

[cquick]

C4 wheat has been a goal in plant science since the green revolution. It's not just a case of shoving the DNA for a few enzymes into the plant though.
The leaf architecture, 'Kranz anatomy', is crucial for C4, as the CO2 is harvested in the mesophyll and then transported as malate to the bundle sheath cells where it is converted back to CO2, but in much higher concentration. This makes the enzyme that fixes carbon, Rubisco, much more efficient as it also has a high affinity for oxygen as well as CO2.

However there is hope that it can be done, as it has evolved independently several times in nature

 

[Minesapint]

Doesn’t maize start off with C3 metabolism and then switch to C4 at a certain growth stage? I must of been sober in that lecture.

 

[Pilatus]

Off Topic.
I know very little about Maize but does it take a lot out of the ground( a lot more than a 10t/ha wheat crop?) as it produces so much Biomass,also do Maize roots go down into the ground very deep there by improving soil structure especially on heavy land. Ok in many cases soil structure will be ruined if harvested while soil is very wet

 

[ollie989898]

Off Topic.
I know very little about Maize but does it take a lot out of the ground( a lot more than a 10t/ha wheat crop?) as it produces so much Biomass,also do Maize roots go down into the ground very deep there by improving soil structure especially on heavy land. Ok in many cases soil structure will be ruined if harvested while soil is very wet

Yes, it takes a shed load out of the ground though when combining it a lot of the stover goes right back on the ground.

I believe the USDA calculated that the average corn yield last year was 177 bushels/acre which works out at 4.5 tonne/acre. It's a bit of a myth that North America grows very low grain yields all over.

Maize is an interesting plant. There are ancient strains of maize that are perennial, and others which are basically aquatic.

 

[Flat 10]

C4 plants mostly tropical plants (certainly warm weather from memory?)