الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
Study was carried out at the Experimental Station of
Agricultural Botany Department, Faculty of Agriculture,
Moshtohor, Zagazig University, Benha branch during 200 I and
2002 seasons on squash (Cucurbita pepo L.) cultivars (32BX~
316, Amco Star, Top Kapi, Obodas, Arlika and Eskandarani).
In the present study, the cultivar Eskandarani considered
as control one. Since, the other cultivars are new hybrids of
squash being cultivated for the first time under the Egyptian
conditions. Seeds of the three hybrids Obodas, Top Kapi and
Amco Star were produced in USA meanwhile Arlika was
produced in Holland, yet, 32BX and 316 were produced in Egypt
(Horticulture research institute).
Study included three experiments:
1- A laboratory experiment: to evaluate the germination
process of seeds cultivars.
2- Open field experiment: to evaluate seedling emergence,
growth character, flowering character, chemical
composition, yield, fruit quality, and disease resistance
to powdery mildew and zucchini yellow mosaic virus of
squash cultivars under natural infection.
3- Greenhouse experiment: to evaluate disease resistance
to powdery mildew and zucchini yellow mosaic virus of
squash cultivars under artificial inoculation.
Tile obtained results could be summarized as following:
1. Germination: the highest germination percentage was
existed in 316 and Arlika cultivars, but 32BX and Arlika
scored lowest germination rate.
2. Seedling emergence: in open field, only Arlika cultivar
increased the percentage of the seedling emergence. But,
only 316 cultivar was decreased the seedling rate.
3. Stem length: 32BX, 316, Amco Star and Arlika were the
best cultivarsbeeause they showed lowest stem length
during the growing season.
4. Leaf area: cultivar 32BX scored highest leaf area but
Ameo Star and Arlika scored the lowest of this area.
5. Assimilation rate: 316 was low in this respect meanwhile
Amco Star, Top Kapi and Obodas exhibited the highest
values of the assimilation rate.
6. Dry weight: was high in 32BX and Top Kapi but 316,
Ameo Star and Arlika showed the lowest total dry weight
plant during growing season.
7. Sex ratio and femaleness: sex ratio was low meanwhile
femaleness was high in each of Amco Star and Arlika; so,
economically these two cultivars considered the best ones.
8. Early fruit yield (kg/plant, No./plant and percentage of
early yield): were the highest in 32BX, Amco Star and
Arlika.
9. Total yield (kg/plant, No./plant and percentage of the
control yield): were the highest in Amco Star and Arlika
but 32BX was the lowest one.
10. Harvest index: was the highest 1I1 316 and Arlika,
followed by Amco Star cultivar.
11. Under artificial inoculation in the greenhouse, squash
cultivars tested were susceptible to powdery mildew
infection, but they were differed in degrees of infection
severities. They divided into three groups, the first
included Obodas as 3 16, which showed the lowest
severities. Cultivars Amco Star, Eskandarani, Arlika and
32BX included in the second groups. The third group
included Top Kapi cultivar. A positive correlation
between the seasons was obtained (0.31).
12. Under natural infection in the open fields, infection
increased when plants become older. A great difference
obtained between the two seasons, when the disease
severities recorded were very high in 2001 than those
obtained at 2002. A positive correlation between the
season was obtained (0.55).Amco Star cultivar showed to
be moderately resistant during 2001. While, in 2002
Arnco star, Obodas and Arlika cultivars recorded as
moderately resistant.
13. All squash cultivars tested against ZYMV mechanical
inoculation, showed different patterns in this reaction to
the disease. Cultivars 32BX, 316 and Arlika showed the
lowest degree of symptoms. As well as, they give low
degrees of symptoms during different intervals of
investigation.
14. Under natural infection in the open fields during the two
seasons of study, cultivar Obodas show low degrees of
infection. Other cultivars showed high degrees of
infection.
Finally, it could be concluded that those cultivars such as
Arlika, Amco Star and 316 characterized with many of the
growth and yield economic characters, hence, these cultivars
could be recommend to cultivate under the Egyptian conditions.