Agriculture Business Week

In the late 90′s we conducted a technology search in Thailand, Malaysia, Singapore and Indonesia. We visited research and extension centers, and documented technologies generated by research institutions. We also conducted on-farm observations of innovative practices that farmers and traders apply in the production and postharvest handling of durian(Durio zibethinus Mur.) and mangosteen(Garcinia mongostana Linn.).

The technology search was useful in fastracking the generation of technologies which we made available to local farmers through the Handbook on Durian Production in the ASEAN and Handbook on Mangosteen Production in the ASEAN. These publications have helped in the expansion of both crops in the country. Durian is now one of the country’s major crops. It has been grown in over 20,000 hectares (ha) and provided high income to many fruit growers, especially the smallholders. It also provided employment to thousands of farm laborers, traders, processors, and businessmen. Similarly, mangosteen is emerging as one of the country’s major fruit crops and medicinal crops, which is being grown in over 5,000 ha.

When the Department of Agriculture awarded the senior writer as Outstanding National Agricultural Scientist in 1996, he used his cash prize to conduct technology search and extensive documentation of the technological practices in the production and postharvest handling of longkong and duku in southern Thailand and northern Malaysia.

One of the technologies that were generated was the superior clones of longkong from Narathiwat which was considered the best longkong in Thailand. Planting materials were mass-produced at reasonable cost. A handbook entitled Lansium Production with Emphasis on Duku and Longkong in the ASEAN was published to serve as guide to farmers. This resulted in the rapid expansion of longkong in the Philippines, which is being grown now in over 10,000 ha.

Large volume of durian, mangosteen, and longkong fruits are expected to be available this year for the local consumption and export particularly to Hong Kong and China.

Encouraged by the successes in fastracking the generation of technologies on . the introduction and production of other fruits and plantation crops in the Philippines, we made four trips to Thailand and Malaysia this year for a series of technology search. We studied their production technology for fruit and plantation crops – aside from durian, ma0gosteen, and longkong – and we found them amazing.

We would like to highlight six of these crops. These include tropical longan, mandarin citrus, tropical lychee, pummelo, rubber hybrid, and palm oil hybrid.

WHY AMAZING?
These crops are considered amazing because first, they provide higher income and prosperity to farmers in Thailand and Malaysia compared to other highvalue crops. Second, the current and emerging technologies for commercial production and postharvest handling of these fruits appear to be applicable under Philippine condition. Third, the crops have a market potential in the Philippines and in international market. Fourth, many Filipino farmers are interested on the commercial production of these crops; however, the production would be limited due to inadequacy or non-availability of technology and planting materials.

We hope that the information we gathered for this article would generate greater interest and efforts from the government and private sectors, which in turn, would be the way for Filipino farmers to have planting materials and to learn production techniques. In doing so, new and exciting farming activities will be conducted from which farmers would generate higher income. We also hope that through this article, new rural enterprises on the production and processing of these crops would be created.

TROPICAL LONGAN
A decade ago in Thailand and Malaysia, tropical longan (Dimocarpus longan Lour.) was an important crop. But now, its production has rapidly expanded to meet the high demand of both domestic and export markets.

The average annual export value of longan in Thailand is US$141 million, the highest among fruit commodities in that country. The value of longan export surpassed the export value of either pineapple or durian which were formerly the two leading fruit exports of Thailand.

Thailand exports fresh and processed longan to China, Hong Kong, Indonesia, Singapore, USA, Canada, France, and United Kingdom. Malaysia, on the other hand, exports the fruits to Singapore and Middle East.

Longan originated from subtropical places in Southern China and Myanmar. For hundreds of years, the cultivation of this crop for food and medicinal purposes is limited to the subtropical southern China. Eventually, the crop was introduced and commercially grown in Taiwan, northern Thailand, Vietnam, Cambodia, Laos, Queensland, Australia, and Florida, USA. However, its cultivation remained unknown in tropical countries like the Philippines.

Longan was introduced to Thailand in 1896 as a royalty gift to the King Rama V from the government of China. The crop was first grown in northern Thailand particularly in Chiang Mai and Chiang Rai where the environment is subtropical. The intensive research done by Thailand’s government researchers and innovative farmers led to the identification of cultivars, which are adapted to tropical environment. The research included extensive on field testing of thousands of chance seedlings and bud sprouts for tropical adaptability.

Some years ago, researchers were able to identify a cultivar called “ping pong,” which flowers and bears fruits regularly under tropical condition. In fact in Mindanao, this cultivar flowers two years after planting. However, the fruits of these cultivar are small and therefore, are of limited export value.

The researchers then identified cultivars which flower in some years and grow vegetatively in many years.

Production was biennial and unpredictable. Further research was, therefore, conducted to address the problem on biennial production.

In the research process, two chemicals were identified to induce massive flowering during on-season and also during off-season. These chemicals are potassium chloride and sodium chloride. The effectiveness of potassium chloride to induce flowering was discovered by a research institution in Thailand, while the use of sodium chloride was discovered by an innovative farmers in Chanthaburi.

The chemicals applied to longan are similar to potassium nitrate which is used in the Philippines to induce flowering of mango.

However, not all longan cultivars are responsive to the chemicals. Longan cultivars “I Do” and “Phet Sakhon” are the most responsive, hence many farmers in the tropical parts of Thailand and Malaysia are using these cultivars. The cultivar i do is more responsive to chemical treatment than Phet Sakhon. I Do grows well and has strong trunks and greenish tip. It starts to bear fruit in four years. It blooms in mid-January and its compressed round and lopsided fruits are harvested in July and August. The fruit’s skin is thick, rather tough, and opaque white while the flesh tastes sweet. This cultivar was already introduced in a farm in Mindanao and its growth, as observed, was promising.

Phet Sakhon, on one hand, is responsive to chemical treatment and an offseason bearer. It blooms more than once a year. Its leaves are small and acute and its fruits are round, have thin skin, and opaque juicy flesh, which contains 18 to 20 percent sugar.

The discovery of the chemicals used to induce flowering of longan has led to the rapid expansion of longan cultivation first in Thailand and later in Malaysia. In Thailand, the area for longan cultivation expanded from 49,256 ha ten years ago, to present 104,000 ha.

The Thai government encourages rice and onion farmers to shift to longan production. During our technology search in Thailand, we observed big orchards in the provinces of Chanthaburi, Rayong, Saraburi, Phechaburi, Songkhla, Samut Sakhon, and Samut Songkran. In Malaysia, we also observed large commercial orchards in the northern provinces of Perlis, Kedah and the southern province of Jahor near Singapore.

Radical increase in the production of tropical longan in Thailand and Malaysia initially resulted in oversupply in some parts of the two countries during on-season. Sometimes, this caused depressed price and lower farm income.

Then another important discovery was made in Thailand, which is extending the shelf life of the fruit. By subjecting newly harvested fruits to sulfur dioxide fumigation, the shelf life of the fruits is extended to 48 days or more. This led to the export of fresh longan to many countries. Moreover, many postharvest and processing technologies were also developed that is why longan products such as canned, dried, juiced, honeyed, jammed, frozen, wined, and caffeined-free longan coffee are out both in the local and export markets.

Longan is a universal fruit and many Filipinos like it. The country imports large volume of longan and is sold in high-end markets such as China towns, and malls. In the past, planting materials for longan production were brought to the Philippines due to an attempt to cultivate it in the country. This effort, however, failed. Now that there are new technologies on the development of tropical cultivars, flower inducement, and prolonging shelf life, there is a big chance for the commercial production of longan in the country to be successful.

MANDARIN/TANGERINE PRODUCTION IN THE FLOODED CENTRAL PLACE
While mandarin or tangerine originated in Southeast Asia and Malesian Archipelago, some cultivars and production techniques, which led to widescale commercial production, were developed in Japan, Brazil, United States, and China.

China developed ponkan, a common citrus fruit, and its complementary production technology under subtropical environment for high yield of over 50 tons/ha at low per unit cost. As a result, China was able to export ponkan to many countries like the Philippines at a low price.

Consequently, the Philippine fruit market is flooded with ponkan and other mandarin oranges from China and lately from Thailand which are more competitive than the local mandarin and sweet orange like dalandan or kahel and perante. Moreover, mandarin cultivars grown in the Philippines like szinkom and lado, also called sintones, dalanghita or naranjita produced lower yields at a high production cost. This is why Filipino farmers are apparently losing the traditional market for lado and szinkom. In a production trial carried at University of Southern Mindanao, the subtropical crop ponkan yielded very low hence, it is uneconomical to produce under tropical condition.

Thailand and Malaysia, on the other hand, were able to develop cultivars and their complementary cultural management practices. Both countries produced high yield of mandarin at low production cost. In Thailand, cultivars shokun and si thong yield an average of 30 tons/ha annually. Its well-managed farms produce over 50 tons/ha yearly.
Malaysia was able to develop a cultivar called limao madu which is very prolific and high-yielding. Fruit growers in Davao who brought planting materials terials for limao madu production from Malaysia are excited about the performance of this cultivar. The plant looks like dalandan except that the leaves of dalandan are smaller.

At Grace Farms, we carried out a comparative yield evaluation of limao madu, dalandan, szinkom and perante oranges. Two-and-a-half year old to three-year old limao madu plants bore approximately 20 tons of fruits per ha; this yield is to three times higher than the yield of other cultivars. The fruits produced are sweeter than szinkom or dalandan. It is projected that when limao madu plants at Grace Farms are five years old, they are capable of producing over 30 tons of fruits per ha.

Presently, comparative yield evaluation of Thai mandarin, limao madu and dalandan is being carried out in Mindanao.

The Philippines imports a lot of mandarin from China, Thailand, and other countries. This, however, shouldn’t always be the case. Filipino farmers can grow high-yielding cultivars from Malaysia and Thailand at a low production cost to compete with the imported ponkan and oranges in the domestic market. In doing so, Filipino farmers would produce affordable mandarin, export it, and derive high income from it.

On the other hand, planting should be done with healthy trees, grafted to calamandarin rootstock. Grafting to pummelo rootstock, however, is not recommended as initial trials at Grace Farms show that it is incompatible.

TROPICAL LYCHEE
Lychee (Litchi chinensis Som.) belongs to the family Sapindaceae which also includes rambutan (Nephelium lappaceum L.) and longan. The crop originated from the southern provinces of China and thrives well under its subtropical climate. From its place of origin, the crop spread to Myanmar, Laos, Australia, South Africa, California, and Florida, USA where it is largely cultivated in subtropical climate.

In recent years, Thailand has developed tropical lychee cultivars and complementary cultural practices for high yields. Thailand produces 89,009 tons of lychee from 24,363 ha planted to this crop. Its fresh and canned lychee are worth Baht949.6 million.

Lychee was initially cultivated in northern parts of Thailand particularly in the provinces of Chiang Rai, Chiang Mai, Phayao, and Nam that have subtropical climate. These places have an elevation of over 1,000 meters above sea level (MASL). Then cultivars were developed for tropical lowland of the southern parts of Thailand whose climatic condition was similar to , that of the Philippines. The development includes evaluation of thousands of plants from bud sprouts and chance seedlings. Both the government research institutions and progressive farmers carried out the evaluation which resulted in the identification of cultivars which could adapt to the tropical lowland.

We observed during our technology search that these cultivars are extensively cultivated in the provinces of Samot Sakhun and Chanthaburi that have elevations of less than 60 MASL. According to some Thai publications, the tropical cultivars developed include the following:

1. Khom. It was derived as a chance seedling of cultivar from China. Being short in stature, it was named khom, which means dwarf in Thai. It is the most popular cultivar that is adaptable to the tropical conditions of lowland central plains and other places in Thailand with tropical climate. It is high yielding. The trees are vigorous, erect, and have long and strong branches with dense foliage. The new flush of growth is red and turns to green at maturity. Fruits are borne in small loose clusters and vary in size and could be either long and heart-shaped or round. The color of its very thick skin is blotchy yellow, and it turns purplish red at maturity. The skin segments are smooth at maturity and vary in size, shape, and arrangement while the protuberances are sharp-pointed. The flesh, on one hand, is tough to fibrous and mild.,

2. Krathon Thong Phrarong. The fruit of this cultivar is large, heart-shaped, colored dark red and far apart; protuberances are small. The flesh is opaque white, juicy, and has an acid-sweet with little astringent taste; sweetness of about 190° Brix. The seeds are large.

3. Khieo Wan. The tree grows to 8- to 10-meter high and has a global crown. Young leaves are greenish yellow while the mature leaves are green. Its spherical fruit, on one hand, is yellowish green. Protuberances are large. The flesh is opaque white and has a sweet with little astringent taste; sweetness is about 17° Brix. Its oval-shaped seeds are large.

4. Samphao Kaeo. The tree grows as high as 10-12 meters. Young leaves are greenish yellow while mature ones are green. The tree bears six to eight heartshaped fruits per bunch. Protuberances are round and short while the skin is dark red. Its flesh is opaque white and has a sour with astringent taste, and the seed is oval.
Due to the universal acceptability of lychee fruits, there were several attempts to introduce the cultivation of this crop in the Philippines. These efforts, however, failed because the plants of unknown cultivars did not produce fruits. But now that tropical cultivars are identified and the corresponding cultural management is in place, there is a high prospect of success in introducing tropical cultivars to the country. In doing so, we could limit or even stop the importation of lychee. Eventually, we might be able to produce and export lychee.

to be continued…