Pearl millet (Pennisetum glaucum (L) R.Br.) is a stable grain crop in the arid
and semi-arid regions of Africa and India, and a new forage and grain crop in Egypt. A
two year field experiments was conducted at El-Maghara Research Station (Middle
Sinai), Desert Research Center, in summer growing seasons 2001 and 2002 . Half
diallel crossing system was established in summer 2001 season among five
genetically diverse varieties and ،or promising lines of five —rowed pearl millet to
obtain a total of ten crosses. The first parent was the commercial cultivar
Shandaweel-1 (P1) and P2 (1CMV88130), P3 (1CMV88904) and P4 (1CMV88908), these
three lines introduced from Indian by Dr. Ebrahim Eisa (Aguic.Research Center) and
the fifth parent (P5) was landrace grown by the farmers at the desert of Red Sea
(Shiatein and Halayeb). The objective was to determine the influence of hybrid and
three systems of water regimes (non stress and stress generated by irrigation at 30,
45 and 60 % available soil moisture depletion, respectively) on fresh and dry forage
yield and drought susceptibility index. Significant differences among the five parents
and their crosses were detected for fresh and dry forage yield at the three cuts and
yield accumulates under the three different water regimes. The two crosses P i P5
and P4 x P5 and the fifth parent (P5) gave the highest mean values for total fresh
weight under the first level of soil moisture (lrri.i), these out yielded the third level of
soil moisture (lrri.3) by 28.-31, 34.29 and 25.01%, respectively. Whereas the two
crosses P4 x P5 and P1 x P5 as well as the third parent ( P3) gave the highest mean
values for total fresh forage yield under the second level of soil moisture (lrri.2) and out
yielded by 16.81, 19.82 and 4.68% respectively.
The magnitudes of gca/sca ratios revealed that additive and additive by
additive type gene action were more important for fresh arnid dry forage yield.
The mean square, due to general and specific combining ability, was highly
significant for the three traits under different water regimes. Moreover, the mean
squares, due to g.c.a. effects, were larger than those due to s.c.a. effects for fresh
weight, drought index and dry weight except the third water regime for the same
character.
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