Wheat Scientific name is Triticum aestvum and it belong to the family Poaceae (1).There are 20 different species of wheat cultivated throughout the world. Due to wheat’s thorough domestication over the past 10,000 years, wheat has lost its natural seed dispersal mechanism and can no longer propagated itself naturally (2).
Pakistan is the 9th largest wheat producer country; accounting for 3.04% of the world’s wheat production from an area of 3.57% of the world Food and Agriculture Organization (FAO), wheat is the leading food grain of Pakistan and being staple diet of the people. It occupies a central position in formulation of agriculture policies. It contributes 14.4% to the value added in agriculture and 3.1% to GDP. 85% of wheat production takes place under irrigation system (tube well, canals) and 15% of wheat production takes place under (rain fed barani) area in Pakistan (3).
Wheat in Pakistan grown under different agro-ecological zones. In irrigated areas wheat is planted after cotton, rice and sugarcane. In rain fed areas wheat is grown in sequence with maize, sorghum, pearl millet and after fallow especially in low rainfall zone (4).
In the Punjab region of India and Pakistan, as well as North China, irrigation has been a major contributor to increased grain output. Use of fertilizer and semi-dwarf varieties in developing countries, has increased yields per hectare. Fertilizer and breeding technique improves its yield. Rotation cropping boost yield by 25%, rotation with canola crop (5)
Globally wheat is a leading source of vegetable protein in human food, having a higher protein content than other major cereals, maize (corn) or rice (6).Wheat grain is staple food used to make flour for leavened, flat and streamed bread, biscuit, cookies, cake, breakfast, cereals, pasta, noodles, couscous and for fermentation make beer and alcoholic beverage or biofuel ( 7,8,9,10). Wheat is used in a secondary capacity in some markets as a feed or livestock. It is also used in thatching material for huts and sod barns (2).
The first identifiable bread wheat ( Triticum aestivum ) identified using DNA analysis in sample form a granary dating to approximately 1350 BCE at Assiros in Greek Macedonia (11). The whole grain can be milled to leave just the endosperm for white flour, the by-product of this are bran and germ. The whole grain is a concentrated source of protein which is 12.1% of whole wheat flour, fiber is 01.9%, Iron is 11.5mg/100g, Phosphorus is 355mg/100g, calcium is 48mg/100g and its caloric value is 341, while the refined grain is mostly starch. (12).In rapidly a developing country of Asia, westernization of diets associated with increasing prosperity is leading to growth in per capita demand for wheat at the expense of the other food staples.
With the country anticipating record production of 25.4 million tonnes of wheat this year, the UN’s Food and Agriculture Organization (FAO) has express satisfactions over rising cereal production in Pakistan in 2014. This increase is due to expansion in area under cultivation, favorable weather conditions during Rabi season in the main wheat producing provinces of Punjab and Sindh and ample supply of fertilizers and water (13). The FAO expect the total cereal production to four percent this year as compared to last year. The total production of cereal crops ( wheat, rice, maize and others) is estimated to be 40.63m tonnes as compared to 39.17m tonnes in 2013 (13).
According to the State Bank of Pakistan’s annual report for 2012-2013, the country produced 24.21 million tons of wheat from and area of 8.66 million hectares in the previous fiscal year of 2013, grew 23.47 million tons of wheat from 8.65 million hectares in 2012 and cultivated 25.21(14).
Total 76% of wheat produced in Punjab, while Sindh produce 16%, KP-5% and Baluchistan produce 3% of total wheat produced across the country (15).The average what production per acre in Sindh is close to 26Mnn, while in Punjab it is around 23 Mnn per acre. In Sindh only 14 million acre land is under wheat cultivation and only 1.8 million acres having two crops per year. There is approximately 3.2 million acres land in Sindh, which can be bough under cultivation through improvement and planning (16). In Sindh we have low crop yield is related to poor management. This includes later planting of wheat due to later maturity and harvest of previous crop like cotton, rice and sugarcane, low soil fertility due to continuous exhaustive cropping system and lack of legumes in the rotation and weed infestation. Crop yields also reduced due to low and imbalance use of fertilizer (4).
In Sindh the other problem is salinity which adversely affects all growth and yield of the crop. Salinity delay emergence and reduces the seedling vigor. This resulted in to poor, patchy crop, which ultimately produce a low yield. This problem can be rectified by the use of salt tolerant varieties and management practices (17).
Botanical description of wheat plant.
It contains two types of root system. These are seminal and clonal roots. The entire roots are adventitious and then have a permanent root system. Seminal roots dry after 30 days of seedling emergence. The culms or stem is erect, elastic, and cylindrical, close to the ground. Called as tillers (primary), which further produces secondary and tertiary tillers having their own root system. Leaves are having two parts sheath and blade. Inflorescence is called ear or spike, the spikelets are sessile having two glumes at their base and arranged alternatively. Each spikelet is composed of three stamens, pistil and ovary. Wheat seed is a caryopsis with a thin walled pericarp enclosing a single seed coat and testa is fused with pericarp. The grain consists of grain, coat, nucellar epidermis, endosperm and embryo. The endosperm constitute 86% of the grain is consist of starch and gluten (19).
Growth stages of wheat plant.
It consists of following stages of wheat plant.
• Pre-establishment stage.
• Pre-emergence and emergence stage.
• Vegetative stage.
• Growth root stage.
• Tillering stage.
• Jointing stage.
• Reproductive stage.
• Post-An thesis stage.
• Maturity stage. (19).
Agronomy of wheat plant.
Sowing of what in Sindh take place between October and December (14). Farmers in Sindh have completed an estimated 97% of sowing target of 1.1 million hectares of wheat by end December (20). The share of Rabi crop (winter/spring crop) from wheat comes 73% as compared to 7% from pulses and 20% from other crops (21). Rabi crop season started from October and continues till March for sowing different crops including wheat (15).
Planting method.
Planting precision is one of the most critical steps in producing successful wheat crop. Proper planting procedure includes time of planting (Oct. 10-30), depth of planting (1-1.5 inches) and seeding rate (35 seeds/ft2). The objective is to establish a crop that will have 30-35 plants/ft2 that are well developed (1.5 tillers/plant) by winter dormancy. (22).
Wheat normally needs between 110-130 days between sowing and harvesting, depending upon climate, seed types and soil conditions. Knowledge of stages is also important to identify periods of high risk from the climate. For example pollen formation from the mother cell and the stage between anthesis and maturity are susceptible to high temperature and this adverse effect is made worsen by water stress (23, 24). Several systems exist to identify crop stages with the Freekes and Zadoks scales being the most widely used.
Seed rate and seed size.
Proper stand establishment requires that seedling in term of number of seeds per unit area (per square feet or linear row foot) rather than pound or bushels per acre. Seed size will vary among varieties and even among seed lot of same variety. Seeds size or the number of seeds per pound can vary from 10,000 seeds per pound to 20.000 seeds per pound. The linear length of row needed to drill 35 seeds/ft2 is calculated by dividing 144 square inches in a ft2 by the drill row width. For example using a drill with 7 inches row width, dividing 144 by 7=20.6 inches of row length 35 seeds at 90% greater germination (22).
Harvesting of the crop began in Sindh and South Punjab in late March and expected to continue till mid June in North Punjab. Harvesting of wheat and other Rabi crop in rain-fed area will begin after May 15 (13). At harvesting time, what stalks begin to bend over from the weight of their kernels, and the entire plant has become golden in color. After wheat is harvested form the field, machinery separates the stalks and chaff away from the kernels. The stalks and chaff often are used in applications ranging from mulch to animal bedding (2).
The germination of seeds is affected by temperature, water availability, oxygen, light, and substrate, maturity of seed and physiological age of the seed. Various plants require different variable for successful seed germination. This also linked with individual seed variety and ecological conditions of plant natural habitat. The minimum water content required to wheat germination is 35% to 45% by weight. Air is composed of 20% oxygen, 0.03% Carbon di oxide and 80% Nitrogen and seeds of most plant species germinate well in and environment providing this mixture of gases. The optimum temperature for germination is 12 to 250C .Specific seed often have a temperature range within which it will germinate. Winter wheat requires exposure to cold temperature to enable flowering. This process is termed vernalisation. This is the acquisition of a plant ability to flower in the spring by exposure to the prolonged cold of winter (25).
Factors affecting seed quality of pre and post-harvest seed.
Precipitation prior to harvest can result in to pre-harvest germination. It is also result in to attack of fungi Cladosporium and Alternaria. Immature seed harvesting having lot of moisture develop microflora grown in the seed lot. If mechanical damage occurs during cleaning, dressing with chemicals, seed treatment, bagging, transportation of seed result in to lost the seed quality. 12% is the ideal moisture for harvesting of wheat. The correct chemical and doses are used when seeds are treated with fungicides and insecticides. Other wise seed may show symptoms of psytotoxicity.
Diseases of wheat.
The main wheat diseases are categorized are:
• Seed borne disease- These include seed borne scab, seed borne Stagonospora (previously known as Septoria) Common bunt (Stinking Smut) and loose Smut. These are managed with fungicides.
• Leaf and head blight diseases- Powdery mildew, leaf rust, Septoriatritici leaf blotch, Stagonospora (Septoria) Nodorum leaf and gum blotch and Fusarium head Scab (26).
• Crown and root rot diseases- There are “Take-all “ and Cephalosporium Stripe, both of these are soil borne diseases.
• Stem rust disease- Caused by basidomycete fungi e.g. Ug99.
• Viral disease- Wheat spindle steak mosaic (yellow mosaic) and barley yellow dwarf are common viral diseases. Can be achieved by using resistant varieties.
Pest of wheat.
Larvae of some Lepidoptera (butterflies and moth) , birds and rodents. All post-harvest losses by borer, beetles and weevils. Resent by “Insect-o-graph” can detect insect in wheat seeds.
Insects and mites
Germination may be affected following insect and mites damage to the seed prior to harvesting (e.g. bollworm) Helicoverpormigera) and during storage (grain borer, Rhyzopertha dominica; weevil’ Sitophilus spp. Or grain beetle Oryzaephilus spp. (25)
Other insects are: Army cutworm, Brown wheat mite, Chinch bug, common Aphid, Army worm, False Wireworm and green bug (27).
Plant Pathogens.
The fungi such as bunts and Smuts (Tiletia spp.) head blight (Fusarium graminearum) and several species of Alternaria and Clodosporium, seed borne Bactria such as Xanthomonas spp. May also effect germination (25).
Seeds are stored at 20 0C with 12% moisture for the period of 360 days will retain about 92% germination. Internal factors like dormancy, which is thus a form of environmental adaptation aiding both plant survival and propagation. Seed with low dormancy level may also prone to pre-harvest sprouting this affecting, falling number and important quality parameter of wheat. The use of certified seed of registered cultivar will aid the producer in limiting potential problems (25).
Hurdle that disturb the market forces in Pakistan ( wheat).
• Natural disaster (flood and earth quack).
• Broker ( middle man)
• The government policies.
• Smuggling of wheat.
• Fertilizer, high yielding varieties of seed and pesticides should be provided in time.
• Monopoly power and Hoarding should be eliminated (3).
Considering all the above points the hi-tech seeds are developed, which are capable of increasing crop out put many times, thus giving a sound return on investment, it can safeguard crop against pest and crop may need less water and survive in drought conditions, it may also sown in hitherto un-head of climate and geographical areas, it may give exotic color and flavor and make storage easier and long lasting (28).
a) The wheat new varieties are developed on the following lines.
• Diseases resistance ( rust, smuts, bunts and barley yellow dwarf virus)
• Stress tolerance ( drought, salt, heat, lodging and shattering )
• Insect tolerance ( Aphid)
• Wide adaptability under varying agro-climatic conditions.
• Quality ( High protein, industrial and good chapatti quality)
b) Sustainability to cropping pattern,
• General purpose varieties.
• Short duration varieties for cotton- wheat and rice-wheat cropping pattern.
c) Development of advanced wheat production technologies.
• Proper sowing time and planting method for different area.
• Input application at proper time and optimum quantity, ( approved varieties, seed rates, fertilizer application, irrigation at critical growth stage)
• Proper weed control (4).
Wheat varieties of Sindh.
• Jauhar-78
Resistance to disease, tolerance to salinity’ Amber grain color, shattering resistance.
• Sindh 81.
Tolerance to rust disease, protein content 15.06% better grain and baking quality.
• Sarsabz
Tolerance to abiotic stress, low input oriented variety. Protein content 14.4%, good grain quality.
• Soghat-90
Resistant against rust diseases, protein content 14.54%, excellent grain quality..
• Kiran-95
Tolerant to low or saline soil, protein content 13.52%, good quality rain.
• Marvi-2000
Resistant to rust disease, protein content 13.46%. Better grain quality.
• Bhittai
Abiotic stress, protein content 14.57%, good grain quality.
• Sassui
Tolerant to water stress, protein content 15%, Amber bold grain, excellent baking quality.
• Khirman
Drought tolerant, protein content 12.91%, Amber bold grain, excellent cokking quality.
• NIA-Amber
Tolerance to disease, heat and cold tolerance, protein content 16.02%.
• NIA- Sunhari.
Heat and disease tolerant, protein content 15%.
• NIA Sundar
Tolerance against stress, highly zinc efficient, protein content 14.08% (29)
• TJ-83
Semi dwarf, does not lodge better performance even under saline condition, good chapatti quality. Average yield 35-40 MDS/Acre
• Mehran-89
High protein content, good chapatti quality, average yield 52MDS/Acre.
• Anmol-91
Dwarf, does not ledge resistance to leaf rust, good chapatti quality. Average yield 40MDS/Acre.
• Abadgar 93
Resistant to leaf rust, good chapatti quality. Average yields 53 MDS/Acre.
• Moomal 2002
Resistant to leaf rust, high protein content, good chapatti quality. Average yields 55 MDS/Acre.
• TD-1
Resistant to leaf rust, high protein content, good chapatti quality, average yield 55 MDS/Acre.
• SKD-1
Resistant to leaf rust, high protein content, good chapatti quality, average yield 60 MDS/Acre.
• Imdad
Resistant to leaf rust, high protein content, good chapatti quality, average yield 55 MDS/Acre.
• Benazir-2012
This variety has given 24% higher yield than TD-1, 41% higher than Imdad-05 and 46% more yield than SKD-1 with yield potential of 87 md/acre. Maturity period of this variety is 126 days, on average weight of 1000 grains is 42 grams, having good cooking quality. Due to short duration in can be grown in both late and early seasons and it shows resistant against leaf rust.
• Hammal
Has yield potential of 7000 kgs/ha (71 md/acre) .It is suitable for cultivation in areas where having water shortage, average yield of 60 md/acre. In dubari condition it have average yield of 25 md/ace. It yielding ability is 17% higher than Mehran-89, 7.7% higher than abdagar-93 and 13% higher than Imdad-05 varieties (31).
Wheat Prices.
Wheat grain prices are stable at Rs.39000 per ton. The new wheat grains are sold at Rs.35000 per ton, due to some moisture (18).Wheat is exported to Afghanistan, SriLanka, UAE, Qatar, Oman, East Africa ( Sudan, Yemen, Kenya) and Bangladesh. (3)
In March the national consumer price index (CPI) was up by 8.5% as compared to the same month last year. Compared to last year the food component of consumer price index (CPI) increased by 9.3% and the non-food component rose by 8%.
Wheat grower have welcomed the governments new support price of wheat for the year 2012-2013 at the rate of Rs.1200 per 40 Kg saying it will encourage the farmers to grow more crop. President of the Kissan welfare Association while talking to APP. He demanded the government to enhance the support price up to Rs.2000 per 40 Kg and suggested that the government should follow the strategy of targeted subsidy on wheat for the poor segment of the country (15).
In 2050 the 334.68 million populations will need about 37.14 million tones of wheat grain and the country must meet these requirements for its integrity (32).
As the population growth slows more land is turned over to the production of biofuel, less wheat may be raised for food causing future price hikes. (2).
High prices of the main staple (wheat) are also a contributing factor for food insecurity especially among low income households, concludes the report (13).
References
1. (oardc.ohio.state.edu) Department of Horticulture and Crop Science. The Ohio State University.
2. (alextiller.com) Alex Tiller’s Blog on Agriculture Farming. An Introduction to wheat- Alex Tiller. Sunday April 15.2007.
3. (slideshare.net) Microeconomic 2; Topic of presentation. Production of wheat and its supply and demand in Pakistan by Mohammad Zawar.
4. Agronomic Practices. To enhance the productivity and sustainability of rain fed and irrigated wheat in wheat based system in Pakistan. Partners: RARI-P, BARI-P, EAR-P, WARI-S, NCWP-F, MARC-F.
5. Swami Nathan Ms (2004) Stock take on cropping and Crop Science for a diverse planet.
6. Nutrient data laboratory. United State Department of Agriculture.
7. Cauvain, Stanley P and Cauvain P. Cauvain (2003). Bread making. CRC. Press .p.540.ISBN: 1-85573-553-9.
8. Palmer, John.J (2001). How to brew. Defenestrate. Pub.CO. p.233. ISBN: 0-9710579-0-7.
9. Neill Richard (2002) Brooze. The drinks bible for the 21st Century. Octopus Publishing Group. Cassell illustrated. P.112. ISBN: 1-84188-196-1.
10. Department of Agriculture Appropriation for 1957: Hearings……….84th Congress. 2nd Session. United State House Committee on Appropriation 1956. P.242.
11. The Science in detail. Wheat DNA. Research. Archaeology. The University of Sheffield. Sheffield.ac.uk. 19th July 211. Retrieved 27th May 2012.
12. Food that heal. The natural way to good health by H.K.Bakhru, 1996.
13. (dawn.com) FAO expresses satisfaction over increase in grain production by Amin Ahmed. Published April 28.2014.
14. ( the news.com.pk) Pakistan likely to miss wheat production target: AFP. Salman Siddiqui. Sunday Jan.26.2014. From Print Edition.
15. (pakistantoday.com.pk). Wheat growers welcome new support price. Nov.24.2012 by APP.
16. (pkissan.com). Issue and Analysis. Understanding wheat shortage in Pakistan and potential of Sindh by Professor Rajab Ali Memon; Former Vice Chancellor Sindh Agriculture university Tandojam, (Translation by Mustaque Rajpur).
17. (uaf.edu.pk). Department of Agronomy. On going project. Introduction of slat tolerance in wheat (Triticum aestivum L.) by seed invigoration techniques.
18. (agrinfobank.blogspot.com) Sindh has adequate wheat stock to meet existing demand by Malik Muhammad. 11 March.2014.
19. (skkmagrisinet.org) Department of agriculture Govt. of Skkim.
20. (dawn.com). Late sowing to help exceed wheat target in Sindh by Mohammad Hussain Khan. Published. Jan. 6.2014.
21. (usda.gov.) Annual Wheat Newsletter. Wheat Research and Development in Punjab (1911-00)[p.122-120]. Lal Hussain Akhtar, Sabir Zameer Siddiqi and Altaf Hussain Tariq.
22. (uky.edu) using proper wheat seeding rates by Morris J.Bitzer and James H.Herbek. Grain Crop Extension Specialist. Vol.2.1994.
23. Slafer Ga, Satorr EH (1999), Wheat Ecology and Physiology of yield determination, Haworth press technology and Industrial. ISBN: 1-56022-874-1.pp322-3.
24. Saini HS, Sedgley, M; Aspinall, D (1984). Effect of heat stress during floral development on pollen tube growth and ovary anatomy in wheat (Triticum aestivum L.). Australian Journal of plant physiology. 10(2): 137-144. Doi. 10.1071/pp 9830137.
25. (grainsa.co.za). Factor affecting wheat seed germination category: SA Graan/Grain, section: Wenartikels, issue. June 2012.
HESTA. HATTING, seed testing laboratory. ARC. Small Grain Institute.
26. Gautam P and R.Dill- MACKY.2012. Impact on moisture host genetic and Fusarium graminearum isolate on Fusarium spring wheat. Mycotoxin Research. Vol.28. issue-1. Doi. 10.1007/S 12550-011-0115-6-2.
27. (ksre.ksu.edu) Wheat Page. Agronomy.
28. (sap.com.pk) Good quality seed give first sign of good hope to the farmers.
29. (nia.org.pk). Nuclear institute of Agriculture (NIA). Wheat principal investigator. Dr. Krim dino Jamali (Head PGB).
30. (sindhagri.gov.pk). Research wing. Wheat varieties evolved.
31. (brecorder.com). Provincial seed council approves, release two wheat varieties. March.8.2013. Business Recorder.
32. Wheat Research Institute, AARI, Faisalabad. Sept. 10. 2012. Breeding of Abiotic stress tolerant (heat, drought, soil salinity).