Saturday, August 9, 2008

Dr. Roberto Coronel: The Sherlock Holmes of Plants

Dr. Roberto Coronel: The Sherlock Holmes of Plants

Fruitful life

HE never dreamt of a career in agriculture, but today, research professor Dr. Roberto E. Coronel has a fruitful life discovering little known plants endemic to the Philippines and propagating them. The fruit-and-nut expert at the Institute of Plant Breeding in UP Los Baños, has in fact been dubbed “the Sherlock Holmes of Plants” by newspaperman-turned-farmer Joe Burgos, for his work in tracking down obscure plants that are all but lost to more popular varieties.

He thought of taking up commerce, recalls this Bulacan, Bulacan native, until an uncle dissuaded him. The uncle had attended workshops and seminars at UP Los Baños during the summer and found the environment agreeable. “He thought this was where I should be,” says Coronel.

Shifting to agriculture sealed his fate. It led to a teaching stint at UP and a lifelong passion for conserving and developing native fruit species which has earned him accolades here and abroad. Coronel’s book, “Edible Fruits and Nuts,” published in the Netherlands, has been translated not only in Filipino but also in other languages, including Bahasa Indonesia and Vietnamese. “It is the most complete reference on tropical fruits in Asia,” he says matter-of-factly.

The Rome-based International Plant Genetic Institute has, in turn, commissioned Coronel to write a monograph on the promotion and use of the underdeveloped pili nut. The Katutubo (meaning, native), he says, is the first pili variety registered in the Philippines. “Until now, it has not been surpassed in terms of productivity and nut size.”

The mother plant which produced Katutubo was among the pili nuts from Oas, Albay, planted in the 1920s along the present-day Pili Drive in UP Los Baños. The drive going to the Institute of Plant Breeding (IPB) is lined with pili trees that, according to Coronel, have a lot of potential and are easy to propagate.

Pili, like the fruits mabolo and balimbing (starfruit) are endemic in the Philippines. He laments, however, that we are fast losing many of our native fruit varieties because we have stopped using them. “For example, in mangoes, the most popular and saleable is the carabao variety so that other varieties like pajo, pico and baluno (a wild mango seen in Mindanao) are becoming very rare. Trees bearing these varieties are being cut to give way to carabao mangoes.”

To track down the country’s remaining native plants, Dr. Coronel does some sleuthing job, with a little help from his staff and some old literature. Despite such efforts, they sometimes fail to save the plants. Recalls this agriculturist: “We read in this Philippine Agricultural Review issue published in the early 1900s that an old mango variety known as Corazon existed in Malabon (now Gen. Aguinaldo), Cavite. We went there in 1978 to collect budsticks to propagate this rare mango, but found out that the owner had cut down the tree. We only saw the stump and knew that we had permanently lost a valuable plant resource.”

He remembers another huge, century-old carabao mango tree heavily laden with fruits in San Jose del Monte, Bulacan, which he knew was still existing in 2000. “But when we returned this summer, the tree was no longer there. We were told that it was hit by lightning.”

Preserving native plants

For the most part, however, Dr. Coronel and his team succeed in their efforts to collect and preserve native plants, such as the galo of Indang, Cavite and the bago of Cuenca, Batangas. “Galo and bago are, like pili and mabolo, underutilized native fruits. They could be raised as garden plants and provide nutritious food for the family.” How does his team operate? “When we go on collecting trips, we get mature fruits and budsticks for evaluation and propagation in the laboratory,” says Coronel. “We measure important fruit characters such as weight, length, width, color and shape of the various parts such as the peel, flesh and seed. We germinate the seeds to produce seedlings and graft the budsticks to produce grafted plants exactly like the mother plant we collected.”

Coronel’s conservation work, however, does not begin and end in his office and laboratory. He carries it at home, too. His backyard in his modest house outside the UP Los Baños campus is full of grafted plants in various stages of growth. There is kabuyaw or kulubot (Kaffir lime), a member of the citrus family, that used to thrive in Cabuyao, Laguna, and which gave the town its name-an industrialized area nowadays. “In the old days, the lime was used as a shampoo but with the advent of commercial preparations, kabuyaw’s popularity went down,” says Coronel. “As it turned out, however, its leaves are much more useful than the fruit. Filipinos, for instance, who have been to Thailand and tasted its famous tom yum soup, would know it uses kabuyaw whose leaves give the dish its distinct flavor and aroma. In fact, I use the leaves in practically everything I cook. Sinigang, bagoong, at kung anu-ano pa.”

There is also bignay, a plant rich in anti-oxidant. Bignay juice has a color and taste that remind one of grapes. Why buy grapes when we can have bignay instead, he asks.

Another plant Coronel is excited about is the miracle fruit, a bush-like plant he and the IPB helped introduce in the Philippines. Native to Ghana and Nigeria in Africa, the miracle fruit is fast gaining popularity here.

What makes it special? Anything sour, like calamansi or green mango, will taste sweet if you take a bite of miracle fruit first, he says. “Though not documented, some cancer patients undergoing chemotherapy have said that eating the fruit helped restore their appetite because it removed the metallic taste in their mouth after the chemo sessions,” Coronel adds.

While most of the plants in his backyard are for sale, there are some which are not, like the Sweet Elena, a big-fruited carabao mango, which is still under study and propagation. “The mother tree is owned by Nida Malabed of Sta. Cruz, Zambales, and was named after Malabed’s mother.” The Sweet Elena shows promise because with its size, 360 grams per fruit, it could very well compete in the world market.

As the incumbent president of the Philippine Fruit Association who has been invited to grace many international fruit symposia, Coronel knows that unless Filipinos face the realities of changing times, we will be left behind in the export market. “Let’s talk about mangoes, for example. By our standards, Philippine mangoes are already the best. But abroad, they pale in comparison to those coming from Mexico and Brazil, which are far more attractive to consumers because of their bigger size and reddish color. We call it red blush. Consumers are easily attracted by the fruit’s outside appearance so we must adapt accordingly if we want to survive and compete. At present, some 90 countries are already producing mangoes, with Latin American countries, notably Mexico and Brazil, as the leading exporters.” Part of his work, Coronel says, is to develop better fruit varieties so that Philippine fruit growers can compete in the export market.

Apart from his backyard garden, Coronel also keeps a four-hectare conservation farm in Calauan, Laguna. “It is not simply a farm. The idea is to conserve, conserve and conserve, especially endemic and indigenous plant species.” Interested growers are welcome to source their plants from the farm, he says.

Coronel is due to retire from the academe next year but given his natural love for all living plants, his farming days are just beginning.

By Corazon A. Ong
Inquirer News Service
Nov. 15, 2003

You may contact Dr. Roberto Coronel at:

RC FRUIT CONSERVATION FARM
Brgy. Mabacan, Calauan, Laguna
(049)536-1919
(0918)573-3378

or visit him at his home fruit nursery at:

9945 Mt. Makiling St., Los Banos Subd.,
Los Banos, Laguna

Growers’ Guide on Abiu Production in the Philippines

Growers’ Guide on Abiu Production in the Philippines


Introduction

Abiu or Caimo (Pouteria Caimito) is native to Brazil and Peru. It has been introduced to other countries including South-East Asia. Abiu in the Philippines was brought from Australia in 1987, and is now fast becoming popular.

The fruit is usually eaten fresh, It is usually sliced longitudinally in four parts and the seeds removed . It tastes best when chilled and flavored with Calamansi juice.

Description

The small to medium-sized, evergreen tree grows up to 16 m high with upright or spreading branches. The leaves are dark green, 26 cm x 6 cm, oblong to elliptic and pointed at the tip.

The flowers are small, greenish-white and are borne in clusters at leaf axils. The fruits are oboivoid-globose, 6-8 cm in diameter and golden yellow when ripe. The flesh is white, soft, juicy and sweet. Each fruit has 1-3, large and flattened seeds.

The fruit and the tree resemble that tof tiesa (Canistel) but the flesh is similar to the taste, softness and sweetness of Caimito (Starapple).

Variety

“RCF GOLD” is the only registered variety of Abiu in the Philippines. Its fruit is round, large (weighs 300 grams) and golden yellow when ripe. Its flesh is translucent white, soft and melting, moderately juicy, sweet (19 Brix total soluble solids) and has high edible portion (63%). It has 1-2, oblong, black, large seeds. Other varieties have been identified but are not yet registered with the National Seed Industry Council.

Climatic and Soil Requirements

Climatic Requirement. Abiu thrives best in the open in places well-distributed rainfall. However, it can also be planted in areas with a distinct dry season if partial shading is provided.

Soil Requirement. Slightly acidic (pH 5.5-6.5), deep, loam soil with good drainageand rich in organic matter is favorable for raising Abiu. It can be planted in flat or slightly sloping areas.

Propagation

Abiu may be propagated by seeds but asexual propagation through Cleft grafting and inarching is recommended. Grafted plants fruit as early as two years while plants propagated by seeds fruit in three years or more.

To prepare the seeds, remove the slimy covering by macerating in fine sand or coir dust. Wash thoroughly in clean water and air-dry.

Sow the seeds horizontally in individual containers (such as perforated black plastic bags) containing good soil, or in a seedbox containing fine river sand or coir dust. Position the seeds with their hilum (large scar) down. Cover with a thin layer of germinating medium. Water and keep the soil moist all the time.

Transplant seedlings established in the seedbed in individual containers mentioned above as soon as the first pair of leaves has expanded and the roots are still short. This is also to check early if the roots are infested with aphids.

With proper care Abiu seedlings grow fast and are ready for field grafting or inarching when they are about a year old.

Planting

Abiu is planted during the start of rainy season, from May to June, with a planting distance of 4-5 m between trees. Prepare holes 30 cm in diameter and 30 cm deep. It is recommended to place a handful of complete fertilizer (15-15-15) before planting. Cover the fertilizer with a layer of soil. Remove the plastic bag from the plant and set the plant at the center of the hole. Cover the hole with soil. Water after planting.

Training and Pruning

Unlike other fruit trees, Abiu branches at an early stage. For easier management of the trees, prune branches growing lower than 50 cm from the trunk. Maintain the treeheight at 2 meters by cutting excess branches. Pruning is done regularly to remove dead. weak or interlocking branches.

Irrigation

During summer months, Abiu trees should be watered especially when the leaves start to wither. Mulching with leaves and grasses around the tree is recommended to conserve moisture in the soil.

Fertilization

Apply compost and manure if available. Mulching also conserves the nutrients stored in the soil. Application of inorganic fertilizers is recommended if Abiu trees exhibit low fruit yield. Apply 200 grams complete fertilizer on newly bearing Abiu trees at the start and end of rainy season. Five-year old trees and above should be fertilized with 500 grams complete fertilizer twice a year.

Harvesting

Plants propagated from seeds start to fruit in three years while grafted plants start to fruit in tow years. Abiu is available all-year-round but the peak of the fruiting season is from December to February. When the fruits turns golden yellow, it is ready for harvesting. A five to seven year old tree usually yields 50-70 fruits.

Abiu is harvested by twisting or pulling from the stem. It usually has a storage life of two weeks.

Reference: Growers’ Guide on Abiu Production by Dr. Roberto Coronel