INTRODUCTION
Maize (zea mais) is the monoecious crop plant which
possesses both male and female sex organs which situated at the different
position.
The male part of the maize plant is known as the tassel and the
female part of the plant is known as the ear.
Normally maize is cross
pollinated plant were by pollen grains from the male part (tassel) are shed to
pollinate and fertilizes the ovum of the female. Under the natural condition,
this process is enhanced through the agents of pollination such as wind and
pollinator insects.
But due to the economic importance of the crop to daily human’s
life, Need of manipulating the production potential of the crop through
improvement of some traits of economic importance, become the task of plant
breeders.
So for the breeders to be able to accomplish this task, different
breeding tools was developed and many of them are still used until today, but
some were improved so as to come out with good results. One among of these
tools which is used by plant breeders in breeding programs is Artificial cross
pollination.
OBJECTIVES OF THE PRACTICAL
To make a cross between two maize varieties.
MATERIALS AND METHODS
In this practical a maize plant with inflorensces (tassel)
and full developed ear, pollination bags and office pins were used. The plant
maize varieties 1 were used as the male parent and plant maize 2 as the female
parent. The tassels of male parent (variety 1) which is still covered by the
flag leaf were selected and covered with the pollination bags. Also female
plant parent (variety 2) which has an ear but their silk has not grown out of
the sheath were selected ready for cross. The ears of the selected female plant
were covered with a pollination bags. Thereafter, the plants were left for few
days until the male plant forms pollen grains and the female plant grows silk
out of the ear sheath. The tassels were sharked and pollen grains collected
into the pollination bag. The ears of the female plant were opened and their
silk cut about 2 cm long from the tip of the ear. The adequate amounts of
pollen grains were poured on the silk so that the silk come into contact with
enough pollen grains. Labels were tied on the ear indicating the parents of the
cross as well as the date when the cross was made. Then the plant left until
grains are developed on the cob and thereafter the pollination bag were
removed. The grains formed were referred as the F1 seeds.
CONCLUSION
Artificial cross pollination in maize enables plant breeders
to come out with the different variety of maize seeds. But the method require
maximum attention in order to
