Wheat improvement in Pakistan (A chapter from The World Wheat Book - a history of wheat breeding - vol 2))

The chapter has been written by Dr. Muhammad Aqil Khan Country Coordinator,  CSISA, Pakistan.

Important links of brochures for Zero til cum Bed Planter and Bed planting in wheat

Zero Till Cum Bed Planter – English

http://www.knowledgebank.irri.org/csisa/images/FactsheetsAndReferences/references/bedplanter.doc (Document; Size: 3.4 MB)

Bed Planting in Wheat – English

http://www.knowledgebank.irri.org/csisa/index.php/en/pakistan-punjab-csisa-hub/item/40-bed-planting-in-wheat (PDF; Size: 3 MB)

Quality Wheat Seed Production and farmers’ misconception

Majority of the farmers are using self-saved seed which, in unsanitary crop production conditions, becomes infested with off type wheat/weed seeds and, overtime, accumulates admixture and seed borne diseases. The use of such seed results in poor crops. Farmers often equate this situation to the variety deterioration. This is only a misconception. Seed doesn’t loose yield potential, it is the accumulated problems which weaken the plants and reduce crop yield. If farmers can maintain their seed, the original yield of the variety is possible year after year. The yield potential of a variety is not lost. Down the road, its resistance to diseases and insects which reduces its usefulness and so gives way to a need for new variety.

 It is easy to maintain the seed. Farmers, large and small, can produce their own seed in separate fields using low seed rate and disease and weed control measures. The row spacing should be wide to facilitate sanitation operations. Doubtful and diseased plants should be rogued during crop growth and maturity. Zero-tolerance should be exercised for unwanted problems- off type and sick wheat plants, other crop plants and weeds. The resultant seed should be as good as any good seed available in the market if not better. Using this plan, a farmer can use his seed as long as he wants or until the variety is replaced. He can then apply this methodology to the new seed. In the present situation when the private and public sectors seed quality is deteriorating, self produced seed especially by progressive responsible farmers, might be the best bet.

Present seed situation is not very enviable. Only 15-20 % seed is produced in the country, the rest is farmers’ old seed. Available seed is often picked up by farmers in periurban areas or by large farmers leaving deep rural situation in misery. Seed is still a magic factor so the farmers in those areas harvest very poor yields. Self production of quality seed is a very practical and economic way to improve deep rural seed situation.

Following technology can be used to raise a seed crop:

Time of sowing: 1-15 November

Seed rate: 25-30 kg/acre

Row spacing: 30 cm apart

Seed: Seed for seed production should be of high quality obtained from a reliable source. Basic seed from a crop breeder can a good start. If, however, seed from breeder or other reliable source is not available farmers can improve/purify their own seed with tangible impact on yield. Seed, if required, should be sifted, graded and purified from weed/diseased seeds and treated with a fungicide against soil borne diseases before sowing. A start with basic seed from a breeder can ensure farmer its certification from seed certification agencies. A seed crop with an unknown seed source is not certified how-high it may be in all quality attributes.

Irrigation, fertilization: As for normal crop.

Weed control: Wheat crop is often heavily infested by a variety of weeds which, over time, have become serious production hazards. Since seed quality standards are stringent and barely allow for disease and weed seeds, a judicious program for weed control is necessary. Major weeds in wheat are Phalaris (Dumbi sitti), Wild oat (Jungli jai), Chenopodium (Bathu) and Convolvulus (Laili). Some other weeds are becoming localized problems; e.g. Jungli matar, Jungli palak etc. Fortunately, all these weeds can be controlled by one or the other herbicide so producing weed free seed shouldn’t be a serious problem.

Rouging: Quality seed production is not possible without crop sanitation which includes keeping diseases, insects and weeds in check and crop free of off-type wheat and other crops plants. Seed producers should be watchful of these menaces and eradicate them timely and properly. Off-type plants eradication require frequent crop visitations and rouging. These plants can be identified from leaf shape and orientation, head size, shape and color. So crop visits during vegetative and reproductive phases are necessary. In eliminating off type plants one should ensure that these plants are uprooted from the ground intact leaving no part in soil to grow again. If farmer is purifying his seed he has to go very much through the same exercise.

Aphid control: Lately aphids have become serious production problem. They multiply very rapidly and can destroy the crop in few days if left unattended. Aphids start from a point (hotspot) which is recognizable from distance due to deeper green color of infested area. Early on they can be easily controlled by non chemical means. A thorough water spray by power sprayer can eliminate the aphid threat in hotspots. But if they spread out chemicals are the only effective remedy.

Seed crop harvest, threshing, bagging and storage: Seed crop should be harvested when the crop is properly mature and grain moisture contents about 12 per cent. The seed crop should be harvested and threshed separately from other varieties. Care should be taken not to mix seed crop bundles with other crop bundles nor seed crop should be threshed using unclean threshers. Threshers should be thoroughly cleaned of any remnant seed of previous crop. Similarly bags should be clean and free of any previous crop and disease debris. It is advisable to use new bags for seed crop to ensure purity and sanitation. The crop should be stored in aerated, well protected store. Proper fumigation and periodic examination of the stored seed is necessary to avoid storage losses.

Quality standards:

Crop certification standards

Crop category	Off type plants	Other crop plants	Obj. Weeds	Disease plants
Prebasic	None	None	None	None
Basic	0.05	None	None	None
Certified	0.20	0.05	0.02	0.2

Seed certification standards

Seed Category	Other variety seeds	Other crop seeds	Inert matter	% germ.
Prebasic	None	None	0.01	85
Basic	0.05	None	2.00	85
Certified	0.20	0.05	2.00	85