Xylem + funghi

Right, here's my question:

Some soil-borne fungi cause wilting in crop plants by growing within the xylem vessels. Which process will be directly affected by these fungi?

I put uptake of water by root hairs. But the answer is: conduction in the apoplast.

I don't understand why? :confused:

Reply 1

iceman_jondoe

18

conduction ? umm well maybe its because water in the xylem forms an unbroken column. I.e. because of the pressure difference in vessels at the top of the plant compared to the bottom water moves up by mass flow...it can do this because of cohesion..the water molcules are attracted together due to their dipoles on the molecules..so maybe the fungi prevents this attraction of water......but i'm prob wrong cause i'm not sure what it means by conduction

Reply 2

WokSz

OP

17

maybe the apoplast pathway from root hair across the cortex?

Reply 3

Aathishree

5

Original post by WokSz

Right, here's my question:

Some soil-borne fungi cause wilting in crop plants by growing within the xylem vessels. Which process will be directly affected by these fungi?

I put uptake of water by root hairs. But the answer is: conduction in the apoplast.

I don't understand why? :confused:

I chose development of root pressure because if the fungi blocks the xylem vessels by growing into it then all water will get accumulated below this level; water potential inside the xylem vessel will continue to increase and will later balance out with the water potential of the soil therefore there will be very little if not no root pressure at all. So the development of root pressure will be affected.
I thought that made sense. But I don't understand how conducting in the apoplast explains the given situation.

(edited 6 years ago)