الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
Two field experiments were carried out in the Desert Research
Center Station at Maryut, Alexandria governorate, during the two
successive summer seasons to study the effect of N, K and P fertilizer
levels on growth and yield and its components as well as mineral content
and chemical composition in both seeds and straw of cowpea plants (Vigna
sinensis, L. var. Kareem 7).
This investigation included 27 treatments which were the individual
and the mutual effect of three levels of N~ K and P fertilizers. The
following is a summary of the most important reesults:
I. Growth characters :
1. There were a significant effect on the studied growth characters
by adding nitrogen level treatments. The highest values were obtained by
using 45 kg N/fed. Also, the highest values of plant height, number of
branches/plant, number of leaves/plant, fresh weight/plant and fresh forage
yield/fed. were obtained at ls1. cut in the 2nd.. season (1994). Whereas,
leaves dry weight/plant. LAI and plant dry weight were superior in tst. cut
at lsi. season (1993).
2. Growth characters were significantly affected by the appliction of
potassium fertilizer levels. In this respect, the best treatment was 48 kg
K20/fed. Maximum values of plant height, number of branches/plant,
leaves number/plant, plant fresh weight as well as fresh and dry forage
yield/fed .. were obtained at 1st.. cut in 2nd.. season (1994). While, the
highest values of leaves dry weightlplant, LAI and plant dry weig.ht were
achieved at tst, cut in 1st.. season (1993).
3. Application of phosphorus fertilizer levels resulted in a significant
responses of all growth characters of cowpea plants. The favourable
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treatment for the highest values was 45 kg P205/fed. In this conection,
plant height, number of branches/plant, number of leaves/plant, plant fresh
weight as well as fresh and dry forage yields/fed. reached its maximum
values at 1st. cut in 2nd. season (1994). Also, maximum values of leaves
dry weight/plant, LAI and plant dry weight were obtained at 1st. cut in 1st.
season (1993).
4. The interaction between nitrogen and potassium had a significant
effect on the studied growth characters. Application of 45 kg N/fed. + 48
kg K20/fed. treatment gave the highest values of plant height, number of
branches/plant, number of leaves/plant, plant fresh weight and fresh and
dry forage yields/fed., at 151.cut in 2nd.. season (1994). Whereas, leaves
dry weight/plant, LAI and plant dry weight were superior at tst cut in both
seasons (1993 and 1994). Whereas, the highest responses were at 151.
season (1993) for both leaves dry weight/plant and plant dry weight. Plant
fresh weight at 2nd. season, fresh forage yield/fed. at 1st. cut in 2nd..
season, also reached to its maximum values by adding (45 kg Nzfed, + 48
kg K20/fed.) treatment.
5. Growth characters differes in the response to the interaction
treatments between nitrogen and phosphorus. Generally, the best treatment
was (45 kg N fed.+ 45 kg P205/fed.). The highest values of both number
of leaves/plant and plant dry weight were obtained at both the two seasons
(1993 and 1994). While the highest value of plant height, plant dry weight
and plant fresh weight were obtained at tst. season (1993) and 2nd.. cut in
2nd. season (1994). Also, there were a significant response for fresh
forage yield/fed. at 1st. season (1993) only. Number of branches/plant and
I..AI were significantly responded at 2nd.. cut in 2nd.. season (1994) and at
tst. and 2nd.. cuts in 2nd. season (1994), respectively.