**3. Conclusions and Prospects of Soybean in Brazil**

Phenotypic observations reported in many articles have characterizedplant response to pho‐ toperiod. Cultivar ''Doko'' was observed to have a long juvenile period [48], based on a long time to flower under short and long daylengths. Late flowering from several sowings was related to the possible existence of a long juvenile period [49]. The "Doko" cultivar was ob‐ tained from a program of selections which were sowedin summer and winter and has long

A Comprehensive Survey of International Soybean Research - Genetics, Physiology, Agronomy and Nitrogen

Genes affecting flowering response, have been studied in *Pisumsativum* and *Arabidopsis thali‐ ana* [51, 52]. The results show that mutations in these species can change various aspects of the photoperiodic control of flowering. Some of these mutations can eliminate the photo‐ periodic responses, which are responsible for flowering induction. Others may simply slow down or speed up responses to photoperiod [33]. Much of the regulatory systems of flower‐ ing are under either positive or negative control and the presence of mutant plants with

Most mutations result in the loss or alteration of the gene activity. After the mutation, the genes that promoteflowering are changed. Mutations that eliminate plant response to photoperiod can block the production of floral stimulus or may interfere with the ability of the meristem to receive the message [33]. Grafting studies have identified genes in *Pisumsativum* that pro‐ mote or inhibit flowering and control the sensitivity of the apical meristem signals [52]. Most cultivars of soybean, respond to photoperiod as follows: when the number of daylight hours is below the critical photoperiod, there is flowering induction. Only few cultivars have the

long juvenile character in which the effect of genes to promote flowering is reduced.

Early studies showed that a long juvenile character in soybean is genetically controlled and can be transferred in a breeding program [53]. Under short days, the authors identified re‐ cessive genes that control the trait. The literature on the subject shows that the long juvenile character is conditioned by recessive genes which can be pleiotropically influenced by other genes in the plant [42, 54-59]. Research conducted under "long-day conditions" indicates that the dominant alleles are responsible for the late cycle: E1/e1 and E2/e2 described by [60], E3/e3 reported by [61], E4/e4 described by [62] and E5/e5 by [63]. In the "short-day condi‐ tions", the opposite occurs [53-55]. Under these conditions, the gene J1/j1 was described [64]. Other studies were conducted to determine the type of inheritance. Research was performed under "conditions of short days" with the genotypes "Hill", "Bragg", "UFV-1", "IAC 73-2736" and "PI 159925" [65]. It was observed that the"long juvenile" characteris controlled by one, two or more recessive genes [3]. These and other studies were fundamental to our understanding of theflowering process of soybean plants grown in locations with different

The possibility of using plants exhibiting the long juvenile character was the solution found by some soybean breeders to delay flowering in short day conditions [42, 54, 58, 66]. Re‐

juvenile period [50].

Relationships

356

**2.5. Genetic Inheritance of Flowering**

latitudes such as occurs in Brazil.

**2.6. Long Juvenile Period in Soybean - Practical Application**

changes in photoperiodic responses is very common.

The achievement of Brazilian research in the development of soybean cultivars adapted to low latitudes has allowed expansion into the central and northern areas of the country. Until 1970, commercial cultivation of soybeans in the world was restricted to regions of temperate and subtropical latitudes which were near or higher than 30º Lat.Brazilian researchers were able to break this barrier by developing cultivars adapted to the short days of the tropics, enabling soybean cultivation anywhere in the country. In the Cerradoregion, more than 200 million hectares were converted into cultivated areas of soybeans and other grains [1].

Currently, states with the highest soybean production are: "Mato Grosso", "Paraná", "Rio Grande doSul" and "Goiás". They produce 82% of Brazil's soybeans. Soybean production is also progressing into new areas in "Maranhão", "Tocantins", "Piauí" and "Bahia", which ac‐ count for 13.0% of Brazilian production.

The projections of the Ministry of Agriculture, Livestock and Supply (MAPA) show that Brazil is a major supplier of food. The region of Matopiba (Figure 10), an area including the states of "Maranhão", "Tocantins"", Piauí" and "Bahia", has potential for growth of grain production and will stand out in the Brazilian agricultural landscape for years to come. The trend shown in the study (Brazil - Projections of Agribusiness 2010/2011 to 2020/2021), re‐ leased by the MAPA [69].

Increased soybean production area can occur through a combination of expansion into new areas or replacement of other crops. The production of sugar cane and soybeans are two ac‐ tivities that compete for land in Brazil. The two together will create an increase of 7.4 million hectares, 5.3 million hectares for soybeans and 2.1 hectares for sugarcane. The soybean plants that have the long juvenile characteristic can also be used in crop rotations, particu‐ larly in areas of ''Sao Paulo'' state that have previously been grown to sugar cane. Cultivars have been developed which are adapted to 1.2 to 1.4 million hectares of this area [70].

Most expansion should occur in areas of high yield potential, such as included in the region that is now called "Matopiba". "Mato Grosso" is not expected to have a large increase in arable land, mainly because land prices in the state are more than double that for land in the "Matopiba" region. Since agricultural expansion into these new areas includes large tracts of farm land, land price is a deciding factor.


**Table 3.** Projections for the production, consumption and trade of soybean (thousand tons).Adapted from [7]. \*Lower Limit \*\*Upper Limit

The estimates for soybean indicate a future Brazilian production of 86.5 million metric tons in 2020/2021 (Table 3) . The annual growth rate is expected to be 2.3% from 2010/11 to 2020/2021. This rate is close to the global rate for the next ten years [7]. The domestic con‐ sumption of soybeans is expected to reach 45.6 million metric tons at the end of the 2020/2021 season, representing 52.7% of the production. The projection is for an annual rate of increase of 1.9%. As it is known, soybean is an essential component in the manufacture of animal feed and is a gaining importance as human food [7]. The projected expansion for the‐ area with soybeans in Brazil should exceed 30.0 million hectares in by 2020/2021. This is an increase of more than 5.3 million hectares from the current level. The expansion of soybean production in the country comes from a combination of expanding areas andincreased yield. Production is forecast to increase at a rate of 2.0% per year with area of production expand‐ ing at the annual rate of 1.9% [7]

Soybean meal and oil will have a moderate increase in future years. Bran exports shall grow at 1.1% per year and the soybean oil exports at 0.5% per year. Domestic consumption for both is expected to grow at high rates. The consumption of soybean oil is expected to grow at an annual rate of 2.2% between 2010/11 and 2020/2021, while the soybean meal consump‐ tion is expected to grow at 2.5% per year.

**Figure 10.** Matopiba.The new agricultural frontier in Brazil.Fonte: [69].

states of "Maranhão", "Tocantins"", Piauí" and "Bahia", has potential for growth of grain production and will stand out in the Brazilian agricultural landscape for years to come. The trend shown in the study (Brazil - Projections of Agribusiness 2010/2011 to 2020/2021), re‐

A Comprehensive Survey of International Soybean Research - Genetics, Physiology, Agronomy and Nitrogen

Increased soybean production area can occur through a combination of expansion into new areas or replacement of other crops. The production of sugar cane and soybeans are two ac‐ tivities that compete for land in Brazil. The two together will create an increase of 7.4 million hectares, 5.3 million hectares for soybeans and 2.1 hectares for sugarcane. The soybean plants that have the long juvenile characteristic can also be used in crop rotations, particu‐ larly in areas of ''Sao Paulo'' state that have previously been grown to sugar cane. Cultivars

have been developed which are adapted to 1.2 to 1.4 million hectares of this area [70].

 **ProductionConsumption Exportation**

2012/1372, 764.7 61,176.9 84,352.4 39,349.0 33,725.9 44,972.2 32,985.5 26,829.9 39,141.1 2013/14 74, 531.2 61,196.3 87,866.0 40,140.8 33,748.6 46,533.1 33,573.3 25,990.3 41,156.3 2014/1576, 241.0 61,344.5 91,137.4 40,921.0 33,839.2 48,002.7 34,262.6 24,693.8 43,831.4 2015/1677, 958.6 61,650.0 94,267.2 41,703.6 33,994.5 49,412.7 35,705.5 24,497.3 46,913.7 2016/1779, 672.0 62,062.8 97,281.3 42,485.8 34,196.5 50,775.0 36,972.7 24,235.3 49,710.1 2017/18 81, 385.8 62,565.6 100,206.0 43,268.0 34,436.6 52,099.4 37,671.2 23,258.6 52,083.8 2018/19 83, 099.3 63,141.3 103,057.2 44,050.2 34,708.1 53,392.3 38,595.2 22,438.5 54,751.9 2019/2084, 812.7 63,778.5 105,847.0 44,832.4 35,006.1 54,658.7 39,774.6 22,022.7 57,526.5 2020/21 86, 526.2 64,468.1 108,584.2 45,614.6 35,326.9 55,902.3 40,744.4 21,430.0 60,058.8

Most expansion should occur in areas of high yield potential, such as included in the region that is now called "Matopiba". "Mato Grosso" is not expected to have a large increase in arable land, mainly because land prices in the state are more than double that for land in the "Matopiba" region. Since agricultural expansion into these new areas includes large tracts of

YearProjection \*L. Lim. \*\*U. Lim. Projection \*L. Lim. \*\*U. Lim. Projection \*L. Lim. \*\*U. Lim.

**Table 3.** Projections for the production, consumption and trade of soybean (thousand tons).Adapted from [7]. \*Lower

The estimates for soybean indicate a future Brazilian production of 86.5 million metric tons in 2020/2021 (Table 3) . The annual growth rate is expected to be 2.3% from 2010/11 to 2020/2021. This rate is close to the global rate for the next ten years [7]. The domestic con‐ sumption of soybeans is expected to reach 45.6 million metric tons at the end of the 2020/2021 season, representing 52.7% of the production. The projection is for an annual rate of increase of 1.9%. As it is known, soybean is an essential component in the manufacture of animal feed and is a gaining importance as human food [7]. The projected expansion for the‐

leased by the MAPA [69].

Relationships

358

farm land, land price is a deciding factor.

Limit \*\*Upper Limit

These data reflect the dynamism of the internal market for these products, given the human and animal consumption.The relationship between consumption and production of soybean oil in future years is around 78%. Most of the oil is for human consumption and the other part has been used for the production of biodiesel. About 22% of the production will be ex‐ ported. For soybean meal, between 47.0 and 49.0% should be directed to domestic consump‐ tion, and about 50% exported. Thisbrief account of the soybean in Brazil demonstrates the importance of this crop to the national economy. The expansion of the area for production of soybean was due largely to basic and applied research involving genetic and physiological mechanisms affectingthe timing of flowering and other developmental events. Thus, much of soybean's expansion has been due to the quality of Brazil's national agricultural research.
