FFTC NEWSLETTER 2003/141 1

FOOD &NEWSLETTER

SEPTEMBER 2003

141 TECHNOLOGY

Use of FFTC leaflets for extensionMore than 130 Practical Technology leaflets now available . . . . . . . . . . . . . . . . .

Reducing the bad odors of livestock wastesMicroorganisms to reduce ammonia and sulfur emissions . . . . . . . . . . . . . . . . . . . .

Soil testing servicesAccess by Asian farmers to soil testing and plant analysis . . . . . . . . . . . . . . . . . .

Articles in this issue

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New publicationsBulletins, Manual on citrus production . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

FERTILIZER

CENTER

New FFTC Manual for citrus growers

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Left: Asian growerharvesting orangesThe fruit are ripe in spiteof their green skin

This month, FFTC publishes its new manual forAsian citrus growers. It emphasizes low-costtechnology suitable for small-scale orchards inAsia, especially in the tropics.

Citrus production in a hot climate has manyspecial features. There is heavy pressure frompests and diseases. Health management is a

topic emphasized in the FFTC Manual.Citrus fruit grown in a hot climate may even

look different from the same variety grown in acooler place. In tropical citrus fruit, maturity of theskin and maturity of the fruit are often notsynchronized. The fruit are edible and sweet evenwhen their skin remains green.

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S

Most Asian governments operate a national soil testing service. How does it benefitfarmers, and how farmers make better use of it?

OIL TESTING and plant analysis are the onlyway to achieve the balanced application offertilizers. The governments of almost every

country in the Asian and Pacific region have beenmaking active efforts to develop diagnostic servicesfor their farmers. These always include soil testing,though not necessarily on an individual farm basis,and sometimes plant analysis as well. In August,FFTC held an international seminar to discuss accessby farmers in the region to soil testing and plantanalysis services, and how this might be improved.

Role of soil testing

In the early years of national soil testing programs,the main aim was to identify any nutrient deficienciesof the soil. This is still a very important function.However, in some industrialized countries such asJapan and Korea, farmers have been applying large

amounts of fertilizer for several decades. The soilnutrient status is already high. The main aim of soiltesting in this situation is sustainable agriculture.

The cost of soil testing

The cost of soil testing is high in relation to theaverage incomes of Asian farms. Some industrializedcountries can afford to provide a subsidized testingservice which farmers can use free of charge. Mostother countries do not try to provide a free testingservice for individual farmers. Instead, they do testsof major soil series and carry out field trials, todevelop standard fertilizer recommendations.

Standard fertilizer recommendations cansometimes be tailored for individual use by computersand suitable software. In Malaysia, an expert systemknown as FERTO (Fertilizer Recommendation Tool)has been developed for high-yielding rice production.Korea has developed an on-line computerizeddatabase which combines information about landuse, soil types and fertilizer recommendations. Use ofthe database is free of charge. You can visit it athttp://asis.rda.go.kr (in Korean only).

In Asian countries, a national soil testing serviceusually begins with fertilizer management for rice.Later, other crops are added, such as important fruitsand vegetables.

Soil testing for fruit crops

Fruit production is becoming increasingly importantin many countries in Asia. Good harvests of fruitdepend on good fertilizer management. Since fruittrees are perennial crops, their performance in anyone year is partly determined by the amount of fertilizerthey received in previous years. The higher the yieldin any one year, the more nutrients are needed in thefollowing year. Trees also need more fertilizer as theygrow in age and size.

A common problem is that growers apply toomuch nitrogen fertilizer at the expense of othernutrients. Too much nitrogen may induce the growthof too many shoots and leaves, which shade the treesand reduce flowering and fruit set. Overuse of nitrogenmay also mean that the harvested fruit has a lowersugar content. ! (Cont. on page 7) !"

Durian trees and riceThis paddy field withyoung durian trees inraised beds will eventuallybecome a durian orchard,giving a higher income.

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FFTC NEWSLETTER 2003/141 3

The Dr. Soils Program

An innovative program in Thailand uses mobile soiltesting vans which visit rural villages. The vansanalyze soil samples brought in by farmers, and makefertilizer recommendations. The program is run by theDepartment of Land Development (DLD).

The "Dr. Soils" are farmers selected from eachvillage who are trained in basic soil testing and landdevelopment techniques. The program has beenoperating for ten years. There are now 63,000 Dr. Soilsfrom 67,000 villages. Dr. Soils are volunteers, who arenot paid a salary but are given a distinctive yellowjacket. The DLD also gives them a small farm pond.

Dr. Soils help DLD staff to train farmers how to takesoil samples. This is very important. If soil samplesare not taken properly, all subsequent analysis isuseless. On the day when the van is scheduled tovisit their village, farmers take their samples to acentral place such as the village temple or school.

They hand in their samples in the morning, and getthe results in the afternoon. While farmers are waitingfor their samples to be analyzed, the DLD staff takethe opportunity to educate farmers about the featuresand management of local soil types, and properfertilizer use.

"If soil samples are not takenproperly, all subsequent analysis

is useless."

Above: A "Dr. Soils"He is carrying an NPK test kit

Right: The mobile soil testing vanBelow: Some standard equipment. Left to right: pHmeter; an ion analyzer for K, Ca and Mg; an EC meter

Visit to the villageAbove: Farmers waiting tohand in their soil samplesBelow: Soil sample analysis

All photos by Dr. Narong ChinabutLater this year, FFTC will publish an Extension Bulletinby Dr. Narong on the "Dr. Soils" program in Thailand

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EB 520 Impact of agrochemicals on soil and waterquality- Leonila M. Varca

EB 521 Pollution of agricultural soil by agricultural andindustrial wastes- Diah Setyorini, Tini Prihatini and UndangKurnia

EB 522 Assessment of agricultural non-point sourcepollutants, and the management of agriculturalsoils - Sun-Gang Yun, Won-Il Kim, Jong-SikLee, Goo-Bok Jung, Jin-Ho Kim, Joung-Du Shinand Hwan Koh

EB 523 A needed paradigm shift for food marketing inAsia- Yang Boo Choe

EB 524 Issues concerned with the marketing of fruits,tree nuts and vegetables in USA: Industrystructure, trade and government policy- Hyunok Lee

EB 525 E-commerce in agricultural marketing- Fu-Shan Liu

EB 526 Analysis of the attitude to farming of peopleusing agricultural machinery

- Tokuhiro Momonoki, Yutaka Sasaki

EB 527 Regulatory framework for genetically modifiedagricultural products in Korea

- Taesan Kim

Soil Management

Marketing

New FFTC Bulletins

GM crops

Attitude of farmersto new technology

Above : White-spotted Longicorn Beetle.Below: Larva of the White-spotted Longicorn Beetle.

The larvae of the White-spotted Longicorn Beetle burrowthrough the wood of citrus trees. Invasion by the beetlecan be prevented by covering the bottom part of each treetrunk with nylon netting or a plastic sheet. Another way ofprotecting citrus trees from the beetle is to paint theirtrunks with lime containing 20% sulfur powder.

For further details, see the new FFTC book CitrusProduction: A Manual for Asian Farmers, in particularChapter 8 (Important pests of citrus in Asia) and Chapter10 (Health management).

Citrus Production: A Manual for Asian growers84 pp. 140 color prints.

More than 1000 free copies of this Manual havebeen sent to agricultural libraries in the Asian andPacific region. If you want to buy your own copy ofthe Manual it costs US25.00 (including packingand postage costs), payable through a bank in themainland United States.

THIS BOOK provides practical technical informationfor citrus growers and their extension advisors inAsia. It follows an integrated approach to citrusproduction. This begins with site selection andlayout of the orchard, and goes on to cover themanagement of soil , water and fertilizer.

One section is on training and pruning,illustrated with 16 line drawings. Another importantsection is on major pests and diseases, with colorillustrations, followed by a chapter on healthmanagement to minimize pest and disease damageat an affordable cost. The final section is onpostharvest handling and storage of citrus fruits.

New FFTC book

All these publications, including the PT leaflets(see opposite page) and the Manual, are availablefree of charge on the Center's website anddatabase at: http://www.fftc.agnet.org

FFTC NEWSLETTER 2003/141 5

Control of golden snail

IN 2003, the Center published 43 more PracticalTechnology (PT) leaflets, while another 51more PT leaflets are to be published in 2003.This will make a total of 131 leaflets on practicaltechnology for small-scale Asian farms. TheCenter 's Deputy Director, Dr. TokuhiroMomonoki, is the organizer of this project.

The leaflets are written by a network ofcoordinators in eight Asian countries, ontopics discussed and approved in advance bythe coord ina tors and FFTC s ta f f . Thecompleted leaflets are published by FFTC anddistributed to the coordinators, who makethem available to national institutes as needed,and also translate them into local languagesfor use by farmers.

To the right are two of the PT leaflets usedby national extension systems. One is apublication in Vietnamese on weed control forpeanut, and the other, from the Philippines, ison alley cropping. !

Use of FFTC PracticalTechnology leaflets

GOLDEN SNAILs, sometimes known as applesnails, are a major rice pest in many Asiancountries. Originally from Florida and SouthAmerica, the snails have few natural enemiesin Asia to control them.

Adult snails cut the young paddyseedlings, or tillers that are less than 21 daysold. Attacks take place mainly at night. Signsof snail attack are paddy tillers floating in thewater, and bare patches in the crop.

Growers in Malaysia have found that theycan control the snails by using rotten jackfruitas a bait. It is best to use freshly rotted fruitswhich have a strong smell. The bait is put outin the field overnight. It should not besubmerged in water. The apple snails gatheron and around the jackfruit, and can begathered and destroyed. !

Above and right: Extension materialspublished in the Philippinesand Vietnam, based on FFTCPractical Technology leaflets

For more details, see FFTC Practical Technology LeafletNo. PT2002-41: Use of Rotten Jackfruit to Control

Golden (Apple) Snail.

Right: Collecting the snails fromaround the jackfruit

Below: Rotten jackfruit used as abait to attract golden (apple) snails

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BAD ODORS are a common problem for peoplewho live near livestock farms. The bad smell ismainly produced by the livestock manure.

Microorganisms which can reduce thesmell of livestock manure

Bad odors from livestock manure are a problem inevery country in Asia where livestock are raisedintensively. A variety of different methods havedeveloped to solve the problem. Some of them arerather expensive, such as a closed composting facilitywith partial ventilation. A cheaper approach whichholds considerable promise is the use ofmicroorganisms which remove or reduce the badsmell. In fact, many commercial preparations arealready being used for this purpose by livestockfarmers in Japan. Their widespread use of theseproducts reflects more the desperation of farmers tosolve the problem, than the effectiveness of suchproducts. Usually it is not clear what microorganismsthese products contain, or how they work. In practice,they often seem to have little effect.

There has been a lot of research in Japan andelsewhere into microorganisms which reduce bad-smelling compounds in raw or composted livestockmanure. Most of these have focused onmicroorganisms which reduce volatile fatty acids.

Reducing the level of ammonia and sulfur

Research into microorganisms which combat bad odor and improve the quality of compost

KURODA KazutakaNational Institute of Livestock and Grassland Science, Japan

Reducing ammonia emissions from compostedlivestock manure

Composting tends to make the smell worse. In Japan,there are 1500 to 2000 complaints about odor fromlivestock production. About one-fifth of thesecomplaints are concerned with bad odors producedduring composting.

When livestock manure is composted, its smellchanges. Raw manure has a rancid odor, causedmainly by fatty acids. Composting changes thisrancid odor to a pungent one. At an early stage of thecomposting process, the volatile fatty acids are brokendown. However as composting proceeds, ammonia(NH3) and sulfur compounds are emitted in largequantities. It is this ammonia and sulfur which areconsidered to be the main cause of odor problems.Furthermore, the emission of large amounts ofammonia reduces the level of nitrogen in the finishedcompost, so it has less value as a fertilizer for crops.

Electronmicrograph

View of the Bacillusmultiplied x 10,000

In recent years, scientists at Japan's National Instituteof Livestock and Grassland Science have beensearching for microorganisms which can reduce thelevel of ammonia or sulfur compounds.

They have isolated many microorganisms whichgrow in compost and manure, and which take up ahigh level of nitrogen. One strain of Bacillusprovisionally described as Bacillus sp. TAT 105 hasa high tolerance for ammonium nitrogen. Very similarto Bacillus pallidus, this bacterium is a heat-loving(thermophilic) species which thrives at a temperatureof around 65oC. In tests, compost treated with thebacterium emitted less ammonia and had a highertotal nitrogen content than the control.

Further tests are now in progress, with theeventual aim of developing an effective biologicaladditive for practical use by livestock farmers. "

FFTC NEWSLETTER 2003/141 7

LIVESTOCK FARMS in Japan often treat theirsolid wastes by composting them. Most cattleand swine manure is composted, and thenapplied to cultivated fields. Generally in thetreatment of livestock wastes, the manure ismixed with a bulking agent such as sawdust orrice straw. This makes the material moreporous, so that it is easier to aerate.

The compost mixture is then heaped into apile. It soon begins to ferment. During theinitial stage of composting, the organic mattertends to break down very rapidly. Thetemperature of the compost soon rises to 60-80oC. (This is hot enough to cause a burn ifskin is exposed for more than a few seconds!!!)

In order to keep the composting material inan aerobic condition, the pile is periodicallylevelled, mixed again, and reformed into a pile(turning). In some composting facilities, forcedaeration or continuous stirring is used ratherthan turning.

Composting and drying the materialsreduced their original volume and weightconsiderably. Furthermore, the nutrient contenthas become stabilized and improved.Composting has the further advantage that itsterilizes weeds and pathogens originally inthe manure. After several months ofcomposting treatment, the result is a dry,powdery, odorless organic fertilizer. !

Composting of livestock manurePile of livestockwastes beingcomposted, JapanNote the steam beinggiven off as the warmcompost comes intocontact with the cold air

Soil testing (Cont. from page 2)

IN THE early days of soil testing services, the mainaim was to ensure that farmers applied enough fertilizerso the crop had all the nutrients it needed. This is stillthe main purpose in some Asian countries, but inothers, the main aim of soil testing today is to makesure farmers don't apply too much fertilizer.

However, there is a problem in defining howmuch fertilizer is "too much". Fertilizer applicationswhich are environmentally friendly are lower thanthose which give the maximum yield. How can farmersbe compensated for this? One way is to adjust theprice, to take the fertilizer management into account.

For example in fruit crops, the higher thenitrogen content of the leaf, the lower the sugarcontent (Brix) of the fruit. In Japan, the labelling andpricing of agricultural products, especially vegetablesand fruits, is beginning to reflect the method ofproduction, and the quality and flavor of the harvest.(Cont. on page 8)

Fruit sold in Japanshowing the Brix

"

Upper left and right:Display of fruits in supermarketLower: Label for home delivery service of tomato

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The Food and Fertilizer Technology Center (FFTC) is aninternational agricultural information center for small-scale farmers in the Asian and Pacific region. It collectsand disseminates information on improved low-costtechnology, with the aim of helping farmers obtainbetter yields and a higher income. Articles in thisNewsletter may be translated, quoted or reprinted,provided credit is given to the source.

Food and Fertilizer Technology Centerfor the Asian and Pacific Region5th Fl., 14 Wenchow StTaipei 10616, ROC on TaiwanTel. (886 2) 2362 6239 Fax (886 2) 2362 0478E-Mail fftc@agnet.org

ISSN: 1010-0628

http://www.fftc.agnet.org

FFTC address:

Home Page:

FFTC QuarterlyNewsletter

(Cont. from page 7)

Soil testing for micronutrients

Nutrient deficiencyLeft: Muskmelon withmagnesium deficiency.Normal melons areshown on the right.

If soil testing detects a nutrient deficiency, theproblem can be solved by applying a small amount(e.g. 20-30 kg/ha) of chemical fertilizer whichcontains the element needed. However, soiltesting for a range of micronutrients is expensive.A cheaper solution may be to apply an organicfertilizer such as composted chicken manure.

Organic fertilizer not only improves the soilphysical properties, but supplies a range ofmicronutrients. While each of these is needed bythe crop only in tiny amounts, the absence of anyone of them may have a very damaging effect oncrop performance. !