Section 3 (Crop Management)

Proceedings of the 8 th Asian Regional Maize Workshop, Bangkok, Thailand: August 5-8, 2002
Maize: A Newly Sequential Crop with Rice in Thailand
Somchai Boonpradub 1 and Sanayh Kraokaw 2
1 Phitsanulok Field Crops Experiment Station, Phitsanulok 65130, Thailand.
2 Field Crops Research Institute, Bangkok 10900, Thailand.
Abstract
Maize is one of the dry land crops grown in a rice-based cropping system. However, its productivity
has been often limited by major management constraints focusing on cultivars and cultural management.
A series of field studies have been conducted since 1998 to study the productivity of maize grown after
rice. It was found that maize grown after rice showed more income and profit as compared to the second
rice. The best planting time for maize after rice was from November to December. After harvesting rice
the land was plowed, harrowed and fertilized with 50-62.5-0 kg of N-P2O5-K2O ha -1 . Hybrid seeds mainly
from single cross hybrids were planted with 0.75 x 0.20 m spacing with 1 plant hill -1 (66,666 plants ha -1 ).
Three weeks after planting, urea (46-0-0) at the rate of 156 kg ha -1 was applied as a top-dressing fertilizer.
To increase maize production in the paddy field, it was necessary to provide adequate water as applied by
furrow-irrigation for its growth. The results also show that the yields of maize under recommended
practices were generally greater than those of the farmers’ ones. It is rather obvious that maize after rice
may be one of the alternatives cropping systems for rice farmers to intensify cropping on their lands
during a dry season in Thailand.
Introduction
In the area where irrigation water is available during a dry season, after the main rice is harvested, it
is soon possible to plant upland crops. The attendant factors with the post-rice environment are
waterlogging and cool temperature at early vegetative stage, drought and high temperature at reproductive
stage, poor soil granulation and soil compaction including short photoperiod (Boonpradub et al., 1998;
Lantican, 1982). Thus, the desirable characters of upland crops for the post-rice are drought tolerance,
waterlogging tolerance, early to medium maturity, photoperiod insensitive, early and rapid seedling
development, tolerance to low and high temperature (Navarro, 1986). Some of the crops that are suited to
this condition are soybean, mungbean (Gomez and Gomez, 1983) and maize (Lantin, 1986).
The most popular cropping systems in Thailand are cereal – legume, i.e. rice – soybean, rice – peanut
and rice – mungbean. Two-crop systems involving legumes are common in irrigated areas and the ricerice-rice
system is becoming widespread because of the promotion of non-photoperiod-sensitive varieties
of rice. However, the second rice in this pattern is often limited by the pests damage particularly brown
planthopper. Hence, a new cropping system being promoted in Thailand is rice – maize. Maize as an
important food and feed could be considered a more suited crop to replace the second rice. There is
probably due to less water consumption than the second rice, break the population dynamics of the pest
particularly brown planthopper, high yield and grain quality, high price and economic return including
increase the amount of maize produced to cover the domestic demand (Boonpradub et al. 1998 ; Granados
et al., 1994). Maize grown in dry season has been successfully cultivated in several countries throughout
the Asian region, including India (Singh, 1986), Philippines (Gassity and Hermenegildo, 1990) and
Vietnam (Tinh et al., 1992).
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