Southeast Sulawesi Province is one of the 21 transmigration destination areas that has been the object of transmigration settlement since 1968/1969. A total of 54, 724 families or almost 210, 588 people had been moved between 1968 and 1997 to 157 settlement units in the area. Transmigrants are estimated to account for 12.60 % of the population of Southeast Sulawesi. The main purpose of this study is to assess the availability of food crop production in accordance with increasing population in Southeast Sulawesi during the period from 1968 to 1997. The objectives include, among others, an attempt at a more detailed analysis of how much of this production growth was due to either intensification or extensification. In Southeast Sulawesi, extensification is directly associated with the transmigration program. An examination of the 1968-1997 trends in the production of major food crops in Southeast Sulawesi revealed that the major contribution of the transmigration program to the production of food crop has been linked to agricultural policy, which witnessed increases in the production of upland paddy (153.60 %), soybean (93.36 %) and wetland paddy (45.53 %), respectively.

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Sri Lanka is considered to be a secondary center of eco-genetic diversity for many crop species. It exhibits a rich floristic diversity distributed over a variety of bio-climatic environments. Sri Lanka's natural forests and protected wetlands harbor all the wild relatives of rice found in the country.
Systematic exploration and collection missions specific to wild relatives of rice were initiated by the Central Agricultural Research Institute (CARI) in 1988 in collaboration with the International Rice Research Institute (IRRI) . One result was the discovery of O. rhizomatis, a new species endemic to Sri Lanka.
Survey, exploration and collection of wild rice germplasm in the target areas were conducted during the period of December 1998 to May 1999 by the Plant Genetic Resources Center (PGRC) . The distribution of the 5 wild species of rice occurring in Sri Lanka is depicted in the maps. Their habitats are also described in this paper.

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For the effective use of cytoplasmic-genic male sterility in F1 rice seed production, the nature of the cytoplasm and restorer gene should be elucidated, because the degree of spikelet fertility can be determined based on the nature of the two components. Three developed lines, RT61C, RT98C and RT102C had the genetic background of Taichung 65, an Oryza sativa cultivar, except for the male sterile cytoplasm and one single restorer gene (Rf) derived from the three different lines of O.rufipogon by successive backcrossing. It was found that spikelet fertility differed between the two genotypes RfRf and Rfrf in these lines, particularly in RT98C and RT102C. That is, the Rfrf plants showed a lower spikelet fertility than the RfRf plants in the two lines. It was suggested that the Rfrf plants had a larger number of deformed anthers in addition to half of degenerated pollen grains compared with the RfRf plants. In this paper, the incidence of deformed anthers, anther dehiscence and spikelet fertility were investigated in the RfRf and Rfrf plants in three lines, and attempts were made to elucidate the causes of the decrease in spikelet fertility in the Rfrf plants.
In the homozygotes of each line, spikelets with all six anther deformed seldom appeared, and anther dehiscence proceeded normally as a whole. If at least one normal anther were present in a spikelet, the fertilization could be achieved normally, yielding fertile grains. Therefore, it is considered that the homozygote in each line showed a high spikelet fertility. On the other hand, although the heterozygote in RT61C showed the same expression of the characters as the homozygote, in RT98C and RT102C, the heterozygote displayed a lower spikelet fertility than the homozygote. It was considered that the expression of the low spikelet fertility in RT98C was caused by the low rate of anther dehiscence in addition to the decrease in the ability of fertilization, while in RT102C, it was mainly caused by the presence of many spikelets in which all the anthers were deformed and the rate of anther dehiscence was low.

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In Paraguay, soybean is widely grown without tillage in heavy clay soil called“Terra Roxa”. As a result of the longterm no-tillage practice, a compacted layer tends to develop at a 5-15cm depth in this soil, which impedes the root development of soybean plants. Little is known about the relationships between the root development and soil layer compacted in the Terra Roxa fields. An experiment was conducted in a field with 3 levels of soil hardness in the compacted layer, which were similar to those of farmers' fields under the long-term no-tillage practice. Different compacted soil layers were made by the passage of tractor wheels 0, 4 and 8 times after rotary tillage at a 15cm depth. At the time of emergence, the tap root length was 9.0cm in the absence of tractor traffic, while the length was 2.9 and 1.6cm by passage of the tractor 4 and 8 times, respectively. In both tractor passage treatments, the soil hardness of the compacted layer induced bends and thickness of the tap root tips of many soybean plants at emergence and resulted in shallow root distribution in the latter growth period. Within a few fine days after rainfall, the soil hardness of the compacted layers increased rapidly and reached a high level resulting in the impairment of tap root elongation. These results indicate that the high degree of soil hardness during a short period of time centering on the period of emergence impeded tap root elongation, and that the shallow poorly developed root system did not improve in the latter growth period. It is suggested that the recent decrease of soybean yield recorded in 1998 and 1999 associated high drought was due to soil compactness in the no-tillage fields.

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China's Yunnan province is a center for genetic diversity in Asian cultivated rice. We have conducted a collaborative research project for rice breeding using a wide diversity of genetic resources from Yunnan and Japansince 1982. We screened the germplasm collection from Yunnan for lipoxygenase-3 (LOX-3) content in embryos by using monoclonal antibodies against LOX-3. The lipoxygenase enzyme catalyzes the oxidation of unsaturated fatty acids containing a 1, 4-pentadiene structure into conjugated hydroperoxy fatty acids. The lack of lipoxygenase enzyme in rice grains may reduce oxidative deterioration during storage. We detected 22 varieties lacking LOX 3, the major component among isozymes in rice seeds, after screening 108 varieties of Yunnan rice genetic resources. Most of the varieties without LOX-3 belonged to Japonica upland rice, and to Types-4 and 6, based on esterase isozyme genotypes. Varieties without LOX-3 displayed the following agronomic characteristics: early heading, round grains, lower amylose content in the endosperm, and glabrous leaves and hulls. The lack of LOX-3 was inherited as a single recessive trait in the cross between“CI-115”lacking LOX-3 and“Norm 20”with LOX-3 activity.“CI-115”is a pure line selected from the indigenous upland variety“Chongtui”. No tight linkage was observed between the lack of LOX-3 trait and the red pericarp trait derived from“CI-115”.

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Initiation of tuber enlargement in water yam (Dioscorea alata L.) is controlled by under short-day conditions. Jasmonic acid (JA), gibberellins (GAs) and abscisic acid (ABA) are considered to play a role in this phenomenon. However, the relationship between the initiation of tuber enlargement and these endogenous plant hormones has not been elucidated.
Thus, we investigated the relationship between the initiation of tuber enlargement in water yams and the contents of endogenous JA, GAs and ABA in the leaves to compare the plants subjected to short-day conditions with untreated plants. In order to initiate the enlargement of tubers, we exposed 60-days-old plants to a 10-hour day length (short-day treatment) 30 times. After the treatment, we extracted the leaves with 80% methanol and then purified them by silicic acid partition column chromatography. Bioassay for GA activity was carried out using the rice-seedling growth test, and the contents of endogenous JA and ABA were measured by gas chromatography.
We detected endogenous JA, GA-like substances and ABA from yam leaves. Tuber enlargement was initiated by short day treatment, and the content of JA and level of GA-like substances in the leaves increased at the same time. These phenomena suggest that JA and GA like substances may be related to the initiation of tuber enlargement. In contrast, the ABA content did not change after short-day treatment but rather remained constant through out the growth stages under natural conditions. These results suggest that ABA is related indirectly to the initiation of tuber enlargement.

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Interspecific progenies of Asian rice (Oryza sativa) with African rice (Oryza glaberrima) were developed by the West Africa Rice Development Association (WARDA), and the identification of grain quality characteristics is urgently required to disseminate the progenies to West Africa. Milling characteristics and grain quality traits of the WAB450 series, which were developed from the cross of CG 14 (O. glaberrima) with WAB56-104 (O. sativa), were examined compared with those of O. glaberrima and several representative O. sativa varieties of West Africa. The 157 O. glaberrima lines, 179 interspecific progenies and 10 O. sativa reference varieties were grown in the 1997 rainy season in the WARDA irrigated fields by a standard method. Additionally, 47 lines of the progenies were grown in the 1998 rainy and 1999 dry seasons to examine the stability of grain quality characteristics to environmental changes.
(1) The progenies were superior to O. glaberrima in terms of husking yield, milling yield and whiteness and translucency of milled rice. Such traits in most of the progenies were comparable to those of the O. sativa reference varieties.
(2) A highly significant correlation was observed in the grain shape and size, whiteness and chalkiness in the progenies between the different cropping seasons, suggesting that those traits are varietal characters consistently observed under different growing conditions. A significant correlation was also obtained in milling characteristics, though the correlation coefficients were much lower than those of the grain quality traits.
(3) The progenies with a high protein content were superior to those with a low protein content in terms of milling characteristics and translucency. The grains in the former were more slender than in the latter.
(4) The existing progenies, developed through two backcrossings to the O. sativa parent, displayed various favorable milling characteristics and grain quality traits compared to the O. glaberrima parent. Therefore, it may be possibile to select promising lines from the existing progenies in these aspects.

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