الفهرس 
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Abstract
Experiments in which Phaseolus vulgaris seeds were germinated and
transplanted in Hoagland nutrient solution (1/4 -strength) either singly or
supplied with decreasing concentrations ofK or P were conducted. A
third experiment was carried out in which seedlings and plants were
stressed with NaCl.
2- All these experiments were designed to investigate the possible effects
of stresses on growth, pigment content, metabolite content and activities
of some related enzymes in seedlings and adult plants of Phaseolus
vulgaris. ”
3- It became apparent that K-, P- deficiency and NaCI in the culture
solution induced significant decreases in all growth parameters
determined. (except for root length in Phaseolus seedlings and plants
treated with decreasing concentrations of either K or P).
4- In relation to control seedlings and plants, Na, K and Fe contents were
significantly decreased whereas Ca, Mg and P contents were increased
significantly in K- deficient seedlings and plants. In P- deficient plants
Na, K and P contents were significantly decreased whereas Ca++,Mg++
and Fe+++ contents were significantly increased. NaCI-stressed
Phaseolus seedlings and plants showed significant increase in Na, Mg,
P and Fe contents whereas K+ and Ca++ contents were significantly
decreased.
5- Phaseolus vulgaris seedlings and plants stressed with either K-, Pdeficiency
or salinity appeared to show significant changes in the total
amount and in the relative composition of the nitrogen and carbohydrate
pools.
-In K_ and P- deficient as well as in NaCI- stressed Phaseolus seedlings
.and plants, Chl.a, Chl.b, anthocyanin and xanthophyll pigment contents
were significantly decreased whereas carotenoid content was found
either to increase significantly (with K- and P- deficiency) or to
decrease significantly (with NaCl- stress), as compared with unstressed
seedlings and plants.
7- In relation to control (unstressed plants), K-, P- and NaCI- stressed
Phaseolus seedlings and plants exhibited pronounced significant
changes in the total amount and in the relative composition of organic
and amino acid pools.
8- Compared with control Phaseolus seedlings and plants, the activities of
both invertase, a-amylase and nitrate reductase appeared either to
increase significantly (with P-deficiency and NaCI stress) or to decrease
significantly (with K- deficiency). PFK activity was found to increase
significantly (with K- and NaCl- stress) or to decrease significantly
(with p, stress) whereas G3PDH activity was increased significantly
(with K- stress) or decreased significantly (with P- and NaC!- stress).
9- The present results are discussed in relat,ion to the mechanisms of action
of K-, p; and NaCI- stresses put forward for plarit metabolism and the
associated effects maintained on growth of Phaseolus seedlings and
plants.