FFTC Practical
Technology
Fruit and vegetables
PT2005-7
Managing Phytophthora disease of durian
P hytophthora palmivora (Butler) has been
considered one of the most destructive organisms
causing several diseases in almost all growth stages of
Pre-planting and planting techniques
! Constructing a drainage system. In Thailand,
durian (Figs. 1 & 2). The disease symptoms come in durian trees are planted in raised beds on flat to
various forms such as root rot, seedling and tree die- semi-flat lands to allow the base of the plants to
back, patch canker or stem rot, and fruit rot before and dry after a heavy rain. This makes the tree more
after harvest, leading to high mortality and more than responsive to dry stress, a prerequisite to
30% yield loss in durian plantations. extensive watering to induce flowering and
Researchers from the University of Southern fruiting. A good drainage system also reduces
Mindanao (USM), Philippines, conducted a uneven fruit ripening and incidence of wet core
technology search in Malaysia and Thailand and and other fruit disorders, and prevents the spread
documented the following technologies to overcome of disease.
the destructive effects of Phytophthora in durian:
Fig. 1. Patch canker caused by Phytophthora
Food and Fertilizer Technology Center (FFTC) Cooperating agency for this topic:
5F, 14 Wenchow St., Taipei 106, Taiwan ROC Philippine Council for Agriculture, Forestry and Natural
Tel.: (886 2) 2362 6239 Fax: (886 2) 2362 0478 Resources Research and Development
E-mail: fftc@agnet.org Website: www.fftc.agnet.org Los Baños, Laguna, Philippines 4030
FFTC: An international information center for Fax: (63 49) 536-0016
small-scale farmers in Asia E-mail: pcarrd@pcarrd.dost.gov.ph
! Adjusting soil pH and applying organic matter spreading canopy like 'Arancillo' and 'D 24') are
(OM) prior to planting. Liming within 30 cm of the effective for disease control and spread. With
soil surface at a radius of 1 m, where majority of these spacings, overlapping of canopies is
the roots are expected to develop, can raise the minimal, allowing good light and penetration.
soil pH. A soil pH lower than 5.3 is highly High-density planting creates humidity and
conducive to Phytophthora organisms. reduces air movement, conditions that favor
Moreover, organic fertilizers, including animal Phytophthora infection. In situations where
waste (e.g. chicken dung), can be applied on soils durian is intercropped with other crops such as
with less than 2% OM. coconut and mangosteen, the leaves of the
! Setting up irrigation facilities. In Thailand, almost intercrops should not overlap with those of
100% of durian farms are provided with good durian.
irrigation facilities before planting. Adequate ! Planting durian in mounds. The plants are placed
water supply helps young durian plants become on top of the soil surface and not in dug holes,
less susceptible to Phytophthora infection. with pulverized soil added around the plants to
Effect of water stress in durian includes premature form a mound. This ensures adequate drainage at
dropping of leaves. the base of the plants, preventing raindrops from
! Using large planting material (LPM) resistant splashing wet bits of soil to the leaves, trunks,
clones. Plants that are 1.5 m tall and above are and stems of the plant. It can create an
more tolerant to environmental stress, so intermittent short, drier condition at the base of
establishment can be rapid, resulting in faster the plant, preventing disease infection.
growth and resistance to diseases. Clones from ! Conducting orchard post-planting activities. It is
Malaysia ('D2,' 'D10,' 'MDUR 79,' and 'MDUR 88') important that durian trees be kept healthy by
and Thailand ('Chanee') are the best in terms of providing adequate fertilization, irrigation,
fruit quality, yield, and resistance to pruning, and other good management practices
Phytophthora. that will make the trees strong and capable of
! Providing adequate space for each plant. In overcoming infection. Moreover, the trees
Thailand, wider spacings of about 8 m x 8 m (for should not be allowed to produce fruits more than
varieties with medium-sized canopy like the plant could support.
'Monthong') to 10 m x 10 m (for varieties with
Fig. 2. Phytophthora fruit rot
