Soil salinity has deteriorated
vast productive agricultural lands (955 million hectares), particularly in dry
regions of the world. In Pakistan, about 42% of the irrigated lands are badly
affected with soil salinity, resulting up to 60% yield losses of major crops.
Under salinity the accumulation of soluble salts in soil surface adversely
affects the growth of most crop plants; however a group of plants called
halophytes can thrive under high salinity. The reclamation of these soils is
expensive however, saline agriculture approach can be employed to best utilize
these lands. Saline agriculture is “An integrated use of genetic resources and
improved agronomic practices to obtain better use from salt-affected soils and
brackish irrigation waters on sustained basis”.
Among fruit trees date palm is indigenous to harsh environments and can tolerate
extreme environmental conditions, including salinity, drought and high
temperature. There is vast scope to re-vegetate these affected lands more
successfully with salt tolerant varieties of date palm (Phoenix dactylifera L.).
The date palm belongs to the family Palmaceae and is an important fruit of
Pakistan. Pakistan is 5th largest dates producing country in the world. Date
palm trees spread over an area of 98000 hectares with annual production of
540000 tones, which is 9% of the total world production of dates. The date fruit
and tree were dear to Prophet Muhammad (PBUH) and the word “Nakhal i.e. date” is
mentioned in the Holy Qur’an more than 20 times. The date is also referred to in
the Holy Qur’an as one of the blessings that would be offered in paradise. The
date has one of the highest sugar levels of all fruits. Therefore, date is an
excellent choice of food for the pregnant women and for those who have just
given birth. The fruits (dates) of the date palm contain a high percentage of
carbohydrate (total sugars, 44-88%), fat (0.2-0.5%), 15 salts and minerals,
protein (2.3-5.6%), vitamins and a high percentage of dietary fibre (6.4-11.5%).
Dates contain elemental fluorine that is useful in protecting teeth against
decay. Selenium, another element believed to help prevent cancer and important
in immune function, is also found in dates. The date palm is the plant of hot
and dry climates and can tolerate extreme environmental conditions, including
salinity, drought and high temperature. In fact, it is more salt tolerant than
any other fruit plants. Accurate information about the growth of date palm in
saline environment and the variability in salt tolerance among cultivars is
largely unknown. The genetic variability among date palm cultivars for survival
and growth under salinity stress provides enormous potential for selecting
promising date palm cultivars to successfully grow on salt-affected lands with
less growth and yield reductions. It is inferred from research at the National
Date Palm Research Centre, Al Hassa, Saudi Arabia that three date palm cultivars
Khalas, Madjol and Barhy are highly salt tolerant.
Pakistan, annually earns around $ 28 million from the export of date’s, which
does not reflect the real potential of this sector. Pakistani date’s export can
be increased up to US $ 250 million per annum by planting better date cultivars
and with better packaging. Some important export markets for Dates are India,
Canada, USA, Germany, UK, Denmark, Australia, Bangladesh, Nepal, Sri Lanka,
South Africa, Dubai, Japan, China, South Korea, North Korea etc. According to
one estimate date palm can be grown on about 2 million hectares of moderately
salt affected lands in Pakistan. This will increase the foreign exchange on one
side and will also gradually improve lands affected with soil salinity on the
other hand. Afterwards these lands can be used for crop cultivation. This will
also expand dates processing and packaging industry and will provide employment
opportunities to local people. This will also uplift the economic condition of
the poor farmers. In Pakistan the climate of the following areas is suitable for
date palm cultivation and production.
In Punjab: Bahawalpur, Dera Ghazi Khan, Muzafar garh, Multan and Jhang
In Sindh: Mirpur Khas, Sukhur, Khairpur, Heydrabad, Nawabshah, Sanghar
In Khyber Pakhtoon Khawa: Dera Ismial Khan, Paharpur, Dhakki, Chadwan
In Balochistan: Turbat, Punjgoor, Gwadar
In Pakistan, about 300 varieties of date palm are grown on large area, including
Aseel, Karbala, Fasli, Kupro, Begum Jhangi, Muzawati, Zahidi, Shakari, Dhakki,
Gulistan, Halavi, Basra and Khudravi. The date palm plants can be allowed to
grow under natural salinity and growth can be monitored to assess the effects of
salinity, to compare the performance of selected cultivars. In addition there is
also need to assess the long-term impact of salinity on date palm growth and
productivity as well as its effects on soil properties.
Date palm is propagated by off- shoots (suckers) emerging from the base of the
palm. Since plants raised form seeds not only bear inferior quality fruits but
almost half of them may be non-bearing males.
Date palm propagation is done by the off-shoots (suckers) which are emerged from
the base of the adult plants. True to type plants are also being produced
through technique of micro-propagation through tissue culture. It is also
important to mention here that in date palm the male and female plants are
separate and for good production there should be at least one male plant for
every 20 female date plants. True to type plants are not produced from the seed,
therefore for new plantations date palm suckers should be obtained from
registered nurseries or from government institutes.
The suckers of suitable size and age should be transplanted in 2 feet deep pit
holes at standard plant to plant and row to row distance of 5 m × 5 m. If the
land is salt affected then at the time of transplanting about 5 Kg gypsum can be
used after mixing with one part of organic matter and 2 parts of medium textured
good soil to fill the pit holes. The new date plants should be irrigated with
good quality canal water for 3 to 4 months so that they can establish their root
system. Afterwards tube well water can be applied.
Date palm plant starts to bear fruit after 3 to 4 years of transplantation and
one plant can produce 60 to 70 Kg of fresh dates. The arid zone of D. G. Khan
represents one of the hottest places in Pakistan; with mean maximum temperature
of 45 oC, and average annual rainfall from 100–250 mm, of which more than 50%
receives in monsoon. A large area in the division of D. G. Khan is also affected
with problem of soil salinity and sodicity. However, luckily the climate of D.
G. Khan division is favorable for date palm cultivation and production. There is
large number of wild date plants everywhere in this region, however being grown
from seeds, the quality of fruit is very poor and has no market value. There is
great scope of date palm cultivation on salt affected lands by planting salt
tolerant cultivars.
Therefore at D. G. Khan sub campus of the University of Agriculture, Faisalabad,
a project for date’s research is going to be executed with the financial support
of Higher Education Commission (HEC) of Pakistan. In this project most salt
tolerant local cultivars of date palm will be identified to re-vegetated vast
areas with salt tolerant verities of date, so that living standard of the poor
people of this area can be improved. This research project will prove a mile
stone in increasing the production and area under date cultivation in Pakistan.
A wild date palm plant happily growing on ultra saline field near Chotti Zerin
area, D. G. Khan, Pakistan
Photo courtesy of Mr. Amjid Bashir
Prof. Dr. Javaid Akhtar is Director of the Institute of Soil & Environmental
Sciences, & Saline Agriculture Research Centre at the University of Agriculture,
Faisalabad.