Proceedings of the Fifth Asian Regional Maize Workshop - Search ...

In 1992, the hybrid maize acreage increased sharply to 12,800 ha, of which ~ was planted
with the NMRI's hybrids.
In 1993, the area planted to hybrid maize in the whole country is about 40-50,000 ha. For
this area, in addition to hybrids developed by official institutions, there are hybrids produced
by several seed companies, including those from CP group, uniseed (Thailand), ICI seed, Bioseed,
Ciba Geigy, and cargill.
It can be concluded that the above mentioned company hybrids are suitable to the ecological
conditions in Vietnam and thei r yield potential ranged from 6-10 t/ha in the various locations.
For our maize program in particular, the following domestic hybrids have been developed
for testing in the recent years:
Non-conventional hybrids:
- Early: LS-3 and LS-5
- Early intermediate: LS-4 and LS-6
- Intermediate late: LS-7 and LS-8
Due to the low price of hybrid seed, its wide range of adaptation, and yield potential
5-8 t/ha, the area under hybrids has rapidly increased.
of
conventional hybrids:
- Single crosses: LDSB-1, LDSB-2, LDSB-3, LVN-6 and LVN-10
- Three-way cross: LVN-11
- Double crosses: LVN-12 and LVN-14.
Yield potential of these hybrids is 5 to 10 t/ha.
III. Achiev--.ts 00 crop ~t research
The research on crop management practices of maize production has covered several technological
aspects including: cropping seasons, densities, fertilizer rates, control of insects and
diseases, intercropping maize with soybean or soybean with maize, etc. We will discuss and show
the impact of 4 major technologies:
1. Technique of transplanting winter .ize seedl ings 00 wet land after two rice crops:
This technique was originally studied and tested in 1982 in Hop Thinh