Citrus Research Program

Dr. E. O. Oyedeji

oyedeji.eniola@nihort.gov.ng

Head of Program

Citrus is one of the most important fruit tree crops in Nigeria utilized both for fresh consumption and industrial processing. It surpasses all other fruit trees as raw materials in fruit drink industry. As a result of the importance of citrus to Nigeria economy and its various species with different management practices, the institute accorded Citrus Programmes with which the institute took off to achieve its research objectives.

At the National Horticultural Research Institute Head-quarters in Ibadan, about 30 hectares of land have been earmarked for citrus research work out of which about 24 hectares have been planted. At Mbato in the South east, the area is even larger, and for the Northern ecology an orchard was also established in Kano.

Mission statement

 Improving the efficiency of citrus production, fruit quality and making fruit available all year round at affordable prices and utilization and processing of citrus into various finished products. The Citrus Programme is to provide improved budded citrus seedlings to citrus farmers at affordable prices so as to increase the total area presently covered by citrus.

Research Activities

The research activities of the Citrus programme include:

  1. Collection, screening, selection and breeding of improved varieties of important varieties of important citrus species.
  2. Development of improved nursery techniques and orchard agro-techniques for citrus production.
  3. Screening and selection of most suitable rootstock for citrus production in Nigeria.
  4. Integrated pest and disease management for citrus cultivation; and
  5. Citrus storage, processing and general utilization.

Selected species for Research

Nearly all the commercially important species of citrus are grown in Nigeria however, the following citrus species have been selected for research in order of priority:

  1. Sweet Orange Citrus sinensis
  2. Tangelo Citrus paradise x C. reticulata
  3. Lemon Citrus limon
  4. Grape fruit Citrus paradisi
  5. Mandarin Citrus reticulata
  6. Lime Citrus aurantifolia

 NIHORT Germplasm Collection

The Institute has a broad germplasm collection drawn from different parts of the world through the assistance of UNDP / FAO (Table 1). The accessions are being maintained as a live gene bank at the institute’s headquarters in Ibadan. The accessions showed varying degrees of adaptability to local environment and out of a total of hundred (100) accessions, only 20% were found suitable for recommendation to growers in terms of fruit yield performance. Constant assessment of the accessions for other desirable characters particularly the fruit chemical properties, juice quality and content, and fruit colour are being undertaken.

Various research works have been carried out on sweet orange and tangelo, the most popular species for fresh consumption and which are also easily amenable to fruit juice processing. NIHORT has a collection of various foreign citrus varieties (Table 1) which are being evaluated for their adaptability to local environmental conditions. Those found suitable have been planted as solid blocks or in progeny orchards, to serve as valuable source of budwood supply base for citrus propagation of budded citrus seedlings. In view of the long life span of the plants are sometimes superimposed on them and they also serve as teaching materials for students, extension agents and citrus nursery farmers.

Table 1. Citrus Germplasm In National Horticultural Research Institute

SWEET ORANGE

MANDARINS

GRAPE FRUIT

Pineapple

Dancy

Maccarty

Parson Brown

Clementine

Ruby-Red

Washingon Navel

King

Foster

Carter Navel

Algerine Tangerine

Marsh-Seedless

Hamlin

Kinnow

Red-mencan

Valencia late

Satsuma (Florida)

Royal

Lue-gin-go

Ortanique

Davis

Agege 1

Kara

Pink-pumelo

Etinan

King (florida)

Silver clustered

Meran

Murcott (florida)

Siamese – Pummelo

Bende

Tunis

Shaddock

Umudike

Sun-shine

Duncan

Campbell-valencia

Ponkon

Red-blush

Jaffa

Cleopatra (florida)

Thompson

Mid-sweet

TOTAL 14

TOTAL = 14

Queen

  

Pope

TANGELO

LEMON

Honiossa

Nova

Eureka

Ruby-Blood

Osceola

Meyer

Pera

Sampson

Lisbon

St. Michael

Nocatee

Ponderosa

Shamuti

Sexton

Bears

Majorca

Lee

Harvey

Sweet Seville

Orlando

Billa-franca

Boonis-Early-Or

Minneola

Rough-lemon

Madam Vinous-Or

Page

TOTAL = 8

Koethen-sweet

Robinson

 

Ridge pineapple

Pearl

LIME

Blood orange

Seminole

Key lime

Natal

Umatilla

Lime

TOTAL = 30

Webber

Rangpur lime

 

TOTAL = 14

Sweet-lime

SOUR ORANGE

 

Narrow leaf sour orange

Thorn-less-key lime

 

Tohiti lime

Savage S. Orange

 

Bitter-sweet

Persian Lime

 

TOTAL = 10

Smooth flat Seville

TANGOR

Sour orange (PAkistan)

Uma-rio

Temple

PUNCIRUS TRIFILIATA

Sour Orange

TOTAL = 1

Attoni

Uma-Ealeo

 

Trifoliate Orange

Flat-seville

 

TOTAL = 8

Sylhet lime

 

TOTAL = 1

Citrus nursery techniques

Improved nursery techniques were developed in order to ensure rapid production of high quality budded seedlings for distribution to farmers. In this regard a package of interrelated nursery activities developed through multidisciplinary research approach which include processing and selection of suitable rootstock seeds, identification of appropriate time of planting, type and rate of fertilizer application, weed control, irrigation, disease pest control, etc. These led to considerable reduction in the time for budded seedling production from previous 24 month period to 12 months. Investigation shows that for optimum bud take in the nursery budding of rootstock seedlings should be undertaken as from February to March but adequate irrigation facilities should be provided.

Budded seedling production and distribution

The institute does not only carry out research on citrus but also produces budded citrus seedlings for sale to farmers. During the last 10 years (1990- 2000) over 1-2 million budded seedling and budwood have been distributed to farmers. The institute is also involved in training citrus farmers through the states ADPs on improved nursery techniques and orchard management. The farmers were assisted with rootstock seeds, rootstock seedlings and budwood. In some cases, budded seedlings were planted on farmers plot for them to compare with what they already had on their field.