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Green-seeds.com:
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Current state of Horticultural Research in Yemen Dr. Munibari, Mahassen
Ali
Dr. Alhakimi, Amin
Dept. of Horticulture
University of Sanaa
Yemen
E.Mail; bensalman@ylink.net
General outlook
Situation and area:
 Republic of Yemen situated
in the south-west of Arabia and is the most fertile and densely populated
country in the peninsula, it lies between 12 and 19-20 north and 45 to 54-20
east. The country is bordered by the Arabian sea in the south, Saudi Arabia
in the north, the Sultanate of Oman in the east, and the red sea in the
west. Yemen has a total land of about 55.5 millions hectares. However, the
cultivated area has been estimated at about 3%. Because of shortage in rainfall,
the cultivated lands ranges from 1.4-1.6 million hectares.
There are about 16 million
hectares classified as range lands and 4.2 million hectares as woodland.
Based on the statistical book of 1995, it has been estimated that 82% of
the cultivated area is utilized for cereal production, grain legumes and
forage crops. Vegetables, and fruits covers only 12%, while the cash crops
planted in 6% of total area. According to 1994 census, the total population
of the country is estimated as 15.8 million, with annual growth rate 3.7
percent and a population density of 28/km?. Water Resources is rainfall,
Wadi Flood-water and Underground water
Climate:
Agro-climatic conditions
in Yemen are classified as semi-arid,arid, and extreme arid. The aridity
depends on the topographical; more rain and luxuriant vegetation and rich
bio-diversity is related to the altitude, aspect, and edifice and biotic
factors. The main annual rain-fall varys from 50-200 mm in the coastal belt
and 800-1000 mm in the Ibb and surrounding areas. The temperature varys
according to altitudes, aspects, and green cover of land. It reaches 38-40
degrees during summer in the coastal region, and in the highlands such as
Dhamar. It drops to zero in winter, and it reaches 32 during summer.
Agriculture is still
largely subsistence oriented and heavily dependent on weather conditions.
Effect of climate and other environmental factors resulted in diversity
and heterogeneity of the vegetative cover structure and density. This led
to diversity of natural vegetation which can be classified according to
topography to six zones (coastal, southern, northern, western, highland
and hadramout plateaux ranglands). There is a great variation in the annual
rainfall. Coastal area is characterized by 50-100 mm while the high lands
are more favourable, they have 400-1000 mm. However, the coastal-area contributes
to the total agricultural production of the country by approximately 39%.
It has been reported that rainfed agriculture was decreased by 40%. Consequently,
digging of wells has been increased in Yemen reaching up to 30,000 wells,
most of these wells are used for irrigation.
Finally, Agricultural
sector plays an important role in the country economy, it contributes by
20% of the national income. Due to the agricultural changes there is still
shortage in the agricultural product to meet the population needs.
Place of horticulture in Yemen:
There are more than
14 species of fruit crops, and about 15 species of vegetable crops. Viticulture
is cultivated in Yemen as well. Ornamental crops, medicinal and aromatic
plants are also grown in Yemen (Table 1 and 2).
Viticulture is the most
important crop in Yemen and it,s considered as oldest and famous in the
Near / Middle East countries. High variation was observed for this crop.
More then 20 different forms or varieties were distinguished belonging to
the white, black and Asemi grape. These all forms were used for table and
resins.
Fruits Area (HA) and Production (MT) in Yemen 1995:
|
Crops
|
Area
|
Production
|
|
Grape
|
21106
|
150563
|
|
Dates
|
18634
|
23188
|
|
Banana
|
9069
|
77370
|
|
Papaya
|
3516
|
57065
|
|
Mango
|
2442
|
9821
|
|
Apricot
|
3538
|
6631
|
|
Orange
|
10101
|
39677
|
|
Lemon
|
906
|
6669
|
|
Mandarin
|
1613
|
9054
|
|
Peach
|
892
|
3928
|
|
Quince
|
90
|
408
|
|
Pomegrand
|
924
|
7110
|
|
Figs
|
374
|
2874
|
|
Apple
|
287
|
1722
|
|
Guava
|
626
|
1843
|
|
Other
|
1108
|
4237
|
|
Total
|
74862
|
402160
|
Vegetables Area (HA) and production (MT) in Yemen 1995 : 
|
Crops
|
Area
|
Production
|
|
Potatoes
|
13601
|
184542
|
|
Tomatoes
|
12929
|
199204
|
|
Watermelon
|
7408
|
93605
|
|
Onion
|
4418
|
61848
|
|
Sweet
melon
|
2897
|
31568
|
|
Okra
|
2624
|
16228
|
|
Cucumber
|
522
|
10683
|
|
Carrots
|
735
|
6844
|
|
Courrat
|
728
|
5131
|
|
Parsley
|
182
|
283
|
|
Beans
|
1735
|
9783
|
|
Jaws
mallow
|
541
|
3279
|
|
Squash
|
544
|
4963
|
|
Capsicum
|
1498
|
7707
|
|
Eggplant
|
373
|
3085
|
|
Other.
Veg.
|
2787
|
30047
|
|
Total
|
53522
|
668800
|
Fruit crops
Table
2. Shows the high number of different species cultivated in Yemen. Yemen
located at the intersection of the African , Asian and Palaearctic ecological
zones, and with great variations in land form and climate within realtive
short distances, is endowed with a rich variety of habitat, species and
genetic diversity. There are numerous endemic species, and many plants
are used in traditional medicine, in local industries and for graizing
and fuelwood. However, human settlement, transformation of the landscape
and over-exploitation of biological resources has resulted in major reductions
in plant species and deterioration of there habitats.
Plant improvement:
Many indigenous fruit
trees and nuts are found in Yemen, these woody plants are valuable genetic
resources as food crops because of their resistance to insect, disease and
their wide adaptation, such species as Walnut (Juglans regia) , wild plum
(Prunus spp.), wild almond (Amygdalus spp.) and figs ( ) are some of wild
relatives of fruit trees found in the mountainous area.
Most of those wild relatives
are utilized as rootstock. There are also wild relatives of other fruits
like wild oil trees such as olives (Olea crysophylla) and some other species
of high interest as industrials or stimulants including Coffea arabica and
Qata edulis.
Wild progenitors of
ornamental species such as Anemone, Colchicum, Arum, Arabian jasmine, Aloe
spp. Agave spp. Apipbyllum sp.
The aromatic and medicinal
plants in the wild habitat such as Lawsonia inermis, Artimisia sp., Mentha
sp., Ocimum sp., Thymus vulgaris, Aloe vera, Agave sisalona, Crocus sativus,
coriandrum sativum, Jasminum sambac, and Foeniculum vulgare. Unfortunately
their numbers are rapidly decreasing as a result of the continuous developmental
activities, the use of herbicides and grazing, and the inconsiderate exploitation.
Most of the species used as medicinal or aromatic species are subject of
extinction mainly because of man activity in the wild..
More then 15 expeditions
were carried out in different parts of the country, Collection is made up
of the nearly 750 samples representing several crops. However, most of the
accessions left in the country were subject to loss due to poor conservation
facilities. Since the establishment of plant genetic ressources unit in
Alkod and Dhamar, all materials collected have been well conserved and the
existing collection size is about 2.500 samples from all crops (cereals,
legumes, vegetable, and fruit). In Yemen in an attempt to establish exsitu
conservation in a manageable way under the collaborative regional programme
of IPGRI/WANANET, several clones of landraces of figs, greeb, and pomegrranate
were planted in the field genebank at the several regional stations and
in the faculty of Agriculture at Sanaa University.
Yemen is rich in highly
variable domesticated crops as well as landraces with unique characteristics.
The main horticulture cultivated crops (Tomato, Brassica, potato, onion,
corriander, garlic, okra,......................), stimulant crops (coffee,
Tobacco, Qat), whereas the main popular fruits are grapes, citrus, dates,
bananas, apples, apricots peaches, pears, plums, almonds, pomegranates,
mangoes, papayas, and guavas.
Landraces have persisted
insitu because of the farming systems. In fact, landraces and local varieties
have been conserved in a dynamic way by farmers since they started cultivation
of crops. By growing a mixture of diversified local materials, farmers were
always able to select varieties adapted to local environmental conditions.
The adoption of uniform
new crops cultivars, nitrogenous fertilizer and increasing mechanization
in agriculture have reduced the area of local crop production and resulted
in the disappearing of traditional diversity based farming systems. Landraces
can still be found in isolated and marginal areas, sush as mountains, oases,
specific areas and islands were local and traditional cultivars are still
grown. The important factors that cause partial loss of landraces in Yemen
are expanding cultivation of Qat (Qata edulis) seasonal flood, distruction,
drought, terraces deterioration, and disertification, .....
Most of the collection
has been identified and small part has been evaluated by the AREA, FOA staff
or in cooperation with IPGRI.
Evaluation parameters
are mostly agronomic reading so far, have not had any impact on the applied
plant breeding work yet. Therefor AREA and Universities reviewing its policies
on evaluation and trying to integrate there material in breeding.
Evaluation of fruit
collection are conducted in parallel to other research and breeding programmes
(grapes, quince, pears, apples, apricots and pomegranates) .
Genebanks and storage facilities
Conservation infrastructures
and facilities in the country varys from region to another The active collections
and the facilities at the plant genetic resources units, and the exsitu
conservation facilities are lacking or at their initial stage and the situation
has to be looked at from the research point of view.
For vegetatively propagated
crops and perennials, field genebanks are used to conserve the collections.
Cold rooms are kept at 0 and - 18 °C for medium term and long term storage,
also there are facilities for temporary storage, with rooms working at 4°C.
Types and progress of
present horticultural research program Agricultural research and extention
is dated back to 1955, when the Elkod experiment station was set up in a
governorate near Aden.
In 1980 research was
implanted at different stations (El kod and Seyiun at wadi Hadramaut) covered
field crop, vegetables and fruit, and some limited livestock research.
In the north of Yemen
, agricultural research started in a fragment and highly uncoordinated manner.
The first research activities were introduced in 1970 through FAO/UNDP formulated
projects in Ibb, Taiz, and Wadi Zabid areas. Then several other donors intervened
and more project with agricultural research components have been established
:
-
The US assisted horticulture project (HITS)
- The Range and Livestock Improvement Project (RLIP) at Dhamar with Netherlands
assestance.
- The Risaba project with British assistance, crop and forestry research
was carried out
- The German assisted plant protection project at Sana,a and Al-Baun
- The Netherlands assisted potato seed production project and Rada, a
Rural development project, have been involved in same crop research.
-The Chines aid at Al Batana area have been tested some cereal and fruit
tree species.
- The University of Sana,a and Aden, and agricultural schools at Ibb and
Surdud also pursued some limited research activities.
- In late 1983 Agricultural Research Authority (ARA) was established at
Taiz and several stations .
- In 1990 the country was unified and the establishment of the Agricultural
Research and Extention Authority was made responsible for carrying out
research and extensions activities all over the country through a network
of seven regional stations and headquarters.
Regional research stations
are located in each of main agricultural zones:
º
Northern costal lowlands (Thihama)
º Southern uplands (Sana,a)
º Central high lands (Dhamar)
º Eastern region (Mareb)
º Northern high lands (Taiz)
º Southern coastal low land and midlands.
º Wadi hadramowt station
Research Achievements:
Achievements of research,
since the creation of ARA in 1983, have been mixed. It is certain that same
progress has been made in vegetable and fruit production (the production
of this crops has doubled in the last 10 years, were the country has effectively
reached selfsufficiency. But the majority of the areas dont not receive
enough attention yet depending on rainfed agriculture, natural resources
conservation, biotechnology and part harvesting treatments.
The previous work has
probably rightly concentrated on agricultural practices including fertilizers,
pesticides, and screening of varieties.
The country is also
facing problems of natural resources degradation. Rapid loss of groundwater,
soil erosion, soil salinization, soil fertility depletion, deforestation,
and loss of indigenous crop, and farming practices in marginal.
In 1995 cultivated area
was estimated at 1.1 M. ha. Of which same 300.000 ha irrigated. Horticultural
area is about 128.384 ha = 12% of total area.
|
Crops
|
Area
(ha)
|
Area
(%)
|
production
(tons)
|
|
vegetable
|
53.522
|
4.9
|
668.800
|
|
viticulture
|
21.103
|
21
|
50.563
|
|
fruit
|
53.759
|
52
|
51.597
|
|
Total
|
128.384
|
---
|
------
|
Objectives of research in vegetables.
º
search for high yielding, good quality varieties
º determination of the most suitable season for growing the crop
with determination of the ideal cultural practices.
º identification of diseases and methods of control
º use of chemical fertilizer and determination of optimum doses.
Several varieties and agricultural practices were recommended :
1.
potato (19 varieties .
2. onion ( 8 varieties ,
3. tomato (21 varieties
4. carrot (9 varieties
5. okra (6 varieties)
6. water melon (5 varieties)
7. cucumber (6 varieties)
8. Sweet melon (4 varieties)
9. squash (7 varieties)
10. cabbage 8 varieties)
11. cauliflower (5 varieties)
12. Hot pepper (5 varieties)
13. sweet pepper (2 varieties)
14. Egg plant (4 varieties)
15. Radish (4 varieties)
16. lettuce (2 varieties)
17. garlic (1 variety)
18. spinach (1 variety)
Objectives of research in fruit:
º
introduction of better varieties
º improvement of spacing and pruning practices
º introduction of modern handling and ripening techniques.
º surveyed cultivated varieties in the country
º disease and pest resistance
º establish rootstock, stading cultural treatments
º improvement of post harvest handling techniques.
Promissing and local fruit varieties and cultivars in Yemen:
1.
Banana: 2 varieties
2. Date palms: 3 varieties
3. Grapes: 9 varieties for table and 3 for raisins.
4. Guava: 2 varieties
5. Mango: 5 varieties
6. Papaya: 4 varieties
7. Apples : 3 varieties
8. Peaches: 6 varieties
9. Nectarines: 2 varieties
10. Plums: 2 varieties
11. Orange: 5 varieties
12. Lemon: 5 varieties
13. Grapefruit: 2 varieties
14. Mandarin: 2 varieties
15. Almond: 2 varieties
16. Apricot: 1 variety
17. Quince: 2 varieties
18. Walnut: 2 varieties
Dates. Unlike many Gulf
countries, there appears to be no preponderance of date palm varieties in
Yemen. Some of the named date palm varieties at present in cultivation are
given below. Early varieties start turning to "Rutab " stage during the
second half of April. The harvest tapers off in the month of July where
`Taal" a late ripening variety comes into the market.
The studies on the local
varieties have allowed to identify a very interesting material. Not all
of them have the possibility to be utilised, but they merit a rather consideration
than it was done in the past. Often cultivars were introduced without considering
the local varieties that are selected for long time and suitable for Yemeni
environment. They could be also used by seedling rootstocks for imported
cultivars, but in some cases incompatibility was seen when they grafted
themselves. These local varieties used as rootstocks for peach and almond
or cultivars if in normal cultural condition will show good performance.
The studies of the improvement
of temperate fruit was started in 1983 at CHRDP, in 1984 at HITS and in
1987 at ARA.
In the first, two project
lowchilling cultivars of apple, peach, plum were introduced, then according
to the appropriate chilling units accumulated during the winter, mid-chilling
apple and cherry was imported.
At ARA several mid chilling
cultivars of peaches, apricot, cherries, apples and pears were imported
with the purpose to extend the harvesting season.
The results of the projects
mentioned have shown that in some species (peach and apple) the imported
cultivars, mainly lowchilling, could satisfy the farmers for the yield and
the consumer for quality if some cultural practices were introduced as routine
management (introduction of pollinator, thinning etc..).
Regarding the suitability
of the cultivars it is necessary to distinguish the areas:
-
Central highlands has good chances of cropping lowchilling apple,Peach
cultivars have shown sensitivity to frost. Local varieties of peach could
overcome that constrain due to late blossom.
-
North Highlands seem to be suitable for the low-chilling cultivars of
apple and peach only.
Concerning the improved
cultivars of apricot, cherries and pear the studies are continuing, but
it is too early to spread information and to develop early enthusiasm.
The research continue for the following aims :
-
set up verification trails of apple, peach in the Central and Southern
Highlands area
- test the potentiality of the local varieties in experimental orchard
located in several area;
- select from the local material lines of germplasm for rootstocks resistant
to drought and high pH.;
- study other rootstocks for peach and apple cultivars resistant to calcium
and high pH.;
- start the survey of bioclimatology in order to evaluate the chilling
requirement of the temperate fruit in Yemen and to arrange the proper
action to break the endo-dormancy of the mid-chilling cultivars.
Research have been conducted also in cooperation with several projects
and national institutes, as:
-
Horticulture Improvment and Training sub project (HITS), is a program
sponsored by the Agency for International Development and Implemented
under contract NE-C- 1698, with the consortium for International development,
carried out by Callfornia State Polytechnic University (POMONA) 1984-1986.
Several introuced varieties and locals were evaluated:
1)Peaches:
16 varieties
2)Nectarines:2 varieties
3)Plums:7 varieties
4)Apricots:7 varieties
5)Cherries:3 varieties
6)Apples:19 varieties
7)Pears:1 varieties
8)Quince:1 varieties
selected varieties were used for rootstock produced .
-
Central Highlands Rural Development Project (CHRDP), sponsored by the
U..K. Overseas Development Administration and Minstry of Agriculture
-Y.A.R,
till 1989. Research conducted on several species as:
1)Coffee:3varieties
2)Oranges: 2 varieties
3)Mandarins:3 varieties
4)Bananas:2 varieties.
Seed production, propagation and nursery:
After
the unification of Yemen in 1990 two seed production projects established
in the country:
-
the national seed multiplication centre with 12 regional branches, the
main activity of these centres is to produce seed for cereals, cotton,
grain legumes, potatoes and anion. The project is receiving some British,
German and Italian technical assistance.
- Potato seed multiplication project in Dhamar which produce 2.500 t, of
potato / year. This project started in 1977 with Dutch assistance and is
still enjoying strong support from the Netherlands. The country is annually
importing large quantities of seed from different sources, mainly from USA,
Denmark, France, Holland.
Table 3. Show the domestic and imported improved seed in Yemen. in 1995.
Large private farmers and an established foreign seed company.
|
Crops
|
Quantity
(Kg)
|
Price
(US$)
|
|
Radish
|
70
|
420
|
|
Melon
|
10.325
|
138.358
|
|
Sweet
melon
|
3.558
|
35.270
|
|
Onion
|
7.591
|
144.008
|
|
Okra
|
1.220
|
7.887
|
|
Tomatoes
|
11812
|
318758
|
|
hot
Pepper
|
180
|
5500
|
|
sweet
Pepper
|
485
|
12388
|
|
Squash
|
4462
|
51228
|
|
Cabbage
|
1390
|
9330
|
|
Cucumber
|
1320
|
13166
|
|
Eggplant
|
200
|
3525
|
|
Cauliflower
|
500
|
14500
|
|
Carrot
|
10857
|
95197.7
|
|
Potatoes<
|
32
|
31268
|
The main problem identified in the seed supply system are:
1)
Many varieties imported are not improved
2) Imports are not based on local research finding by AREA.
3) There are no garantees given for seed germination and quality.
4) Proper storage facilities are not available.
Nursery and fruit propagation:
|
Seedling
type
|
Area
/ha
|
N°
of nursery
|
N°
of seedling
|
|
Deciduous
|
36
|
9
|
110674
|
|
Citrus
|
33
|
6
|
42216
|
|
Papaya
|
20
|
4
|
26431
|
|
Mango
and guava
|
17
|
3
|
32829
|
|
Pomegranate
|
32
|
1
|
5040
|
|
Dates
|
8
|
1
|
-----
|
|
Bananas
|
2
|
1
|
-----
|
|
Coffee
|
13
|
8
|
-----
|
|
Ornamental
|
11
|
4
|
-----
|
|
Total
|
143
|
38
|
227190
|
There are over 38 nurseries
for production of fruit tree, these nurseries have traditionally been the
responsibility of Ministry of Agriculture and Water Resources, Regional
developments of Agricultural projects, and commercial unites.
Fruit tree seedling.
in theory, are sold at cost and there has been no regular monitoring of
seedling survival rate, once planted. Most of fruit trees grown in highlands
area . The most of land area in the highlands is steep and rugged, and increasingly
vulnerable to erosion due to changing social patterns, inappropriate agricultural
practices and renoval of woody vegetation.
Cultural practices:
The result of good yield
is linked by several actions that the farmer must undertake. If avery cultural
practice or choice is carried out poorly it becomes a limiting factor on
the production..
Two cultural practices
often forgotten. They are request'ed in all the cultivars cropped. The first
one is the thinning. It is a complexion of the winter pruning in order to
avoid the annual alternative production and to increase the quality of the
fruit. The fruit during the first stages of the growth produce giberellines
that is an antagonist hormone to the cytochinine in the flower bud induction.
The reduction of the number of fruits on the tree enchances the size and
the total yield. The second is the pollination. It must be developed
by using pollinazer and bees. The direct effect of the good pollination
is the presence in fruits of many seeds. They induce a swelling of the fruit
(paricularly in the apples) and a better regular shape.
Fertilizer Supply in Yemen:
The use of inorganic
fertilizer was unknown in Yemen until the late 1960s. Although the use of
the fertilizer has increased dramatically since the time, reaching an all-time
hight of 50.000tons in 1995. The average application increase reaching 23
kg/ha in 1995.
The public sector influence
in the fertilizer supply status in Yemen is through the foreign exchange
control and licensing procedures, while the private sector played an undeniable
role in fertilizer supply to the country. The foreign fertilizer donations
constituted a large portion of the available fertilizers.
The fertilizer supply for the period 1971-1987 was characterized by
the following :
Importation of fertilizer
to Yemen is sporadic since 1970 with a marked decline of imports since 1983
and a prominent fertilizer shortage in recent years. The total fertilizer
imports in the period 1984-1986 averaged 7.600 tons per year which was only
25% of the 29.800 ton per year imported for the period 1982-1983. The fertilizer
supply in 1987 was still only 40% of the 1982-1983 average. The end result
is an unstable fertilizer market, fertilizer shortage and an increase in
fertilizer prices (e.g. the average price for urea was 286 Yemeni Rials
per bag of urea which is more than 400% of the Yemen 70 per bag farm price).
The national average of fertilizer usage in Yemen is among the lowest in
the world (5.5kg/ha). N,P,K and organic mater are recommended for the deciduous
fruit trees and micronutrient deficiency corrected using foliar fertilizers
containing microelements.
It is expected that
application of fertilizers should increase the yield by 25-30%. Application
of potash and phosphorous would be justified only when such need is proved
experimentally. Such experimentation would also be needed to determine optimal
dosages of nitrogen.
The Yemen Soils:
Soil surveys in Yemen
show that most of the agricultural soils have properties that are characteristic
of arid region soils elsewhere. Significant crop yield increases are possible
by the use of fertilizer on these soils.
Most of Yemen,s soils
are calcareous, and they tend to be alkaline, with pH of 7.0 or higher in
many cases. There is a low level of organic matter, which means that the
soils have very low capacity for providing available nitrogen for a crop.
Generally speaking, they test in the low to medium range for phosphorus
and have high levels of exchangeable potassium.
Yemen,s soils are generally
high in potassium. However, some crops, such as grapes, bananas, certain
other tree fruits, tomatoes and potatoes often require more potassium than
is ordinarily released by the soil.
Most Yemeni soils are
calcareous and tend to be alkaline with low organic matter and a very low
capacity to provide nitrogen (5). However, the soil survey of the Dhamar-Yarim
and Amran regions (6) revealed a calcareous silt and those of the Sadah
plains being characterized by coarser alluvial materials.
During plant nutrition
investigation (13) it was reported that the soils are generally alkaline
with rare intensive magnesium deficiency which appears at excessive potassium
application. Boron deficiency is associated with well leached sandy, acid
soils, nitrogen content is low-medium; phosphorus is very low to low and
potassium is high to very high. Most common nutrient disorders in vineyards
are associated with very sandy soils.
The unavailability of
phosphates is attributed (10) to the very alkaline Yemeni soils. In the
highlands, deciduous fruits, particularly apples, have a high requirement
of potassium while calcium is considered adequate and available in these
alkaline soils.
In general, the total
soluble solids are within a normal range and nitrogen and phosphorus are
adequate with potassium at rather high levels in the soil at most Yemeni
nurseries (9). Magnesium and iron tend to be low but sulphur and chlorine
are in normal range.
The Yemeni soils ultimately
require supplemental nitrogen (5) for virtually all crops except legumes.
Phosphorus deficiency shows up when nitrogen application becomes substantial.
Potassium is generally high.
Soils in the areas lying
next to the mountain range have been developed from gravel deposits worked
down from the mountains and subsequently subjected to weathering agencies,
wind and water. The soils at present are being used as grazing land. In
the middle belt, soils consist of fine alluvial silts and coastal sands,
laid down by streams. They are fine textured, deep and generally calcareous.
Wherever water is available if these soils have been brought under cultivation.
The soils in the coastal
belt are light, sandy loam and mostly saline. Since date palms are known
to have higher degree of salt tolerance, most of the date plantations have
been established in this narrow belt of a few to several kilometres in width.
Tihamma plain has slight
slope towards the Red sea and this provides natural drainage. These soils
appear to support date palms without any ill effects; deficiency of other
inputs in places is apparently responsible for poor growth and productivity.
Pest and Diseases:
The following primary
pests have been identified on citrus in Medinat.
Black
fly (Aleurocanthus Woglumii)
Cotton cushiony scale (Icerya purchasi)
Black scale (Paralatoria ziziphi)
California red scale (Aonidiella aurantii)
Leaf miner
Psylids
The following disease
have been identified in Medinat.
Gumosis
(Phytophthora parasitica and P. citrophora)
Malsecco or Anthracnose
Tristeza, virus (suspected)
Greening disease, virus (suspected) Dr. W. Gassert and Dr. Askari)
Cristacortis, virus. (J. Bove)
Xyloporosis, virus (Cachexia) (J. Bove)
Insect Pests and Diseases:
The lesser date moth
is a very serious pest of date palms and is rendering considerable damage.
Graphiola leaf-spot is widespread. The subject has been discussed in greater
detail by Dr. Haider El Haidari, Consultant on Date Palm Pests.
Date Harvesting, Packing and Marketing :
No facilities exist
at present to cure and pack the dates or to market the produce in any organized
manner, with the result that the bulk of the produce is consumed at "Rutab".
Small quantities of "taal" variety which cannot be disposed of in fresh
stage are sun-dried and pressed in baskets of varying sizes, woven from
date palm leaves. Date growers either sell the fruit at the orchard site
or in the local markets from where the middle-men take it to consumer centres
in the region. Inadequate communication channels in date producing regions
present a serious handicap in efforts to improve the culture and develop
speeder and safer disposal of perishable commodities.
The subject of curing,
packing and marketing will be covered in greater detail by the Date Processing
Expert who will be undertaking a consultancy mission to Yemen during the
crop harvest season in 1980.
Inadequacy of research facilities:
A good research set-up
in the agricultural sector is already functioning in Yemen, with its main
Agricultural Research Centre located in Taiz, with several sub-stations
in different agricultural zones already functioning and rendering very useful
service to improve agricultural output in the country. However, research
efforts have not so far been extended to include any studies on the date
palm.
Introduction of exotic date varieties:
Improvement in fruit
production, especially in dates, can perhaps be achieved more easily, economically
and in a relatively shorter time through the introduction of foreign varieties
and by commercially exploiting the ones found most adaptable to local conditions.
However, this approach offers some of its own problems.
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Green - Seeds Co., Ltd.
81/10B Ho Van Hue Street, Phu Nhuan District, Ward 9, Ho Chi Minh City, Vietnam
Tel: +84 (8) 847 6901 - Fax: +84 (8) 844 1392 - Email: info@green-seeds.com
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