Grape is commercially cultivated in Punjab due to its precocity and high economic returns. Besides being grown on commercial scale, it can also be planted in kitchen garden. Fruit contains fair amount of minerals like potassium (0.15-0.25%), calcium (0.004-0.025%) and vitamins like B-complex (391-636 mg/100g). Its juice isa good stimulant of kidneys, mildly laxative and an excellent thrust quincher.
Climate and Soil
Commercially grapes are grown in climate ranging from temperate to tropical around the world. However, grapes do best under a long, hot, dry and rain less summer with adequate sunshine followed by a winter cold enough to induce dormancy in the vines.Specific heat units are required for ripening of a particular cultivar.cultivar. Perlette, an early ripening variety requires 1600 heat units. Dry weather during flowering, fruit development and maturity is essential for the production of quality grapes. Early rains result in cracking of berries and spoilage of crop. Moist weather also favors the spread of fungal diseases.The best soil for grape is sandy loam, well-drained, fairly fertile with good amount of organic matter. Salt affected, nematode infested and water-logged soils should be avoided. Soils having electrical conductivity up to 1.5 mmhos/cm, calcium carbonate up to 10%, lime concretion up to 20% and pH up to 8.7 are suitable for successful cultivation of grape.
Punjab MACS Purple (2008) : It is rich in anthocyanins- a source of antioxidants and is suitable for processing in to juice,nectar and ready to serve beverage. It contains 60-65% juice with total soluble solids 17-18% and acidity 0.50%. It has medium and loose bunches. The berry is seeded, medium in size and purple at maturity. It matures in first week of June.
Flame Seedless (2000) : Bunch is medium and well filled.Berry seedless, firm, crisp, light purple at maturity. It also gives good response to quality improvement treatment. Bunches have berries with 18% T S S. It ripens during second week of June. For uniform color development of Flame seedless grape, retain 75%crop load (80-90 branches / vine) immediately after branch emergence and spray 400 ppm ethephon (a.i.) at color break stage.
Beauty Seedless (1968) : It performs well under south-western districts. Bunch is medium and well filled. Berry seedless, medium,bluish black. Highly responsive to quality improvement treatment.Treated bunches have oblong berries with 16-18% T S S. Keeping quality is poor. Fruit ripens in the first week of June. Average yield per vine is 25 kg.
Perlette(1967): This variety is cultivated on more than 90% of total acreage of grapes in Punjab. Bunch is medium to large and compact. Berry is seedless, firm, crisp, juicy and light amber. It is highly responsive to quality improvement treatment. Treated bunches have large round berries, with 16-18% TSS. It ripens during first week of June. Average yield per vine is 25 kg.
Prepare cuttings during December-January from vines that bear good crop and are free from the attack of insects, diseases and nematodes. Make cuttings from middle portion of one year old canes.The cuttings should be 30 - 40 cm long with a diameter of pencil thickness having at least 3-4 buds. Basal cut should be straight and below the node while the top cut should be slanting and 2-3 cm above the node. Plant cuttings in February on well prepared flatbeds in the nursery. Keep one third portion of the cuttings above ground and bury the remaining two-thirds in the soil.
The rooted cuttings of grapevines are transplanted in the field during middle of January to first fortnight of February before they start sprouting. Vines are planted at a distance of 3mx3m in the pits of 1x1x1 meter dimension. If the soil is light the size of the pits can be reduced. The pits should be filled by mixing 50 to 60 kg well rotten farmyard manure with half of the top soil. The refilled pits should be watered a few days before planting the vines. In each pit,add 5 ml of chlorpyriphos 20 EC mixed in about 2 kg soil against white ants.
Training and Pruning
Training : Train the vines on bower system. The vines are trained as single stem upto the height of bower. The axillary shoots on the trunk of vine are pinched off. The growing tip is pinched off at 79 8015 cm below the bower level. Two laterals are selected at the top and they are allowed to grow on either side in opposite direction.These two laterals become primary arms. Develop three pairs of secondary arms from each primary arm and train them along each wire in opposite direction. The length of primary and secondary arms should not be extended too fast. The entire area available for the framework of vine should be covered in installments otherwise the arms develop too much waste wood which does not encourage the development of fruiting canes.Grapevines should be trained to Y-trellis structure at a spacing of 1.5 x 4m. This system gives high yield, improves fruit quality and enhances maturity.
Pruning : Recommended pruning intensities for different cultivars in Punjab.Name of Planting Training Number of Number of variety distance system canes per vine buds per(metres) cane Perlette 3x3 Bower 60-80 4 Beauty Seedless 3x3 -do- 60-80 4 The grape variety Flame Seedless and Punjab Purple should be pruned at 4 bud level for higher yield and better quality fruits.
Note: 1. Pruning should be done from mid-January to the first week of February when the vines are in the dormant condition.2. Badly trained young vines can be re-trained by removing the faulty limbs. In old woody vines, cut the vine at ground level during the dormant season and retain a shoot emerging from vine near the ground level. This single shoot is trained like the newly planted vine.
Rejuvenation and Top Working Technology
The old Perlette vines trained on bower system can be successfully rejuvenated by heading back the primary arms leaving behind 1 foot stubs in the month of December-January. Bordeaux paste should be applied after heading back of primary arms.Flame Seedless variety of grapes can be successfully top worked on Perlette vines. For obtaining maximum success, tongue grafting should be done in the last week of February on one-year old shoots(canes). This technology advances maturity of Flame Seedless by 4-5 days and improves fruit quality.
Manures and Fertilizers
To newly planted vines apply 60 g urea and 125 g muriate of potash in April and repeat the same dose in June. For older vines planted at 3x3 m distance the following fertilizer schedule may be adopted.Age (year) FYM Dose per tree (g)(kg) Urea Super phosphate Muriate of Potash1 20 400 1500 2502 35 500 2500 3503 50 600 3500 5004 65 800 4000 6505 and above 80 1000 4500 800 Apply whole Farm yard manure(FYM) and superphosphate as well as half N and K fertilizers after pruning. Apply remaining N and K after fruit set in April. Use of high doses of fertilizers may result in excessive vegetative growth and barrenness. Complete shade under bower is an indication of excessive growth. In that case, the nutrient content of soil should be checked with a soil test and the fertilizer dose be adjusted, if necessary. Give two sprays of urea @ 1.0%first at full bloom and second at fruit-set to get higher yield and better fruit quality in the Perlette grapes.
Note : *For preparing 40ppm GA3 solution, dissolve one gram of GA3 in 50 mlethyl alcohol in a thoroughly dried container and make the volume to 25 liters by adding clean water. In case of non-availability of ethyl alcohol use 100 ml country spirit or methyl alcohol.
Time Number After pruning in the I st fortnight One irrigation of February First week of March One irrigation After fruit set in April till I st week of May At 10 days interval During the rest of May Weekly interval June 3 or 4 days interval July to October Irrigate when prolonged dry spell or rainfall is insufficient.November to January One irrigation if soil gets extremely dry.
Give pre-emergence application of Hexuron 80 WP (diuron) @1.2 kg/acre in the first fortnight of March after thorough ploughing.To remove the established weeds spray Glycel 41 SL (glyphosate)or Gramaxone 24 WSC (paraquat) at 1.6 liters/acre in 200 liters of water as post-emergence when weeds attain the height of 15-20 cm.
To get optimum yield and quality adopt the following package of treatments.1. Thin flower buds one week before flowering by leaving 100-120 flower buds/panicle.2. When berry size is 4mm, girdle the vine by removing a 4mm wide ring of bark from the main stem and dip the clusters in 40ppm GA3*. While girdling, there should be no injury to the wood and no piece of bark should remain attached with the wood.3. One week after the first GA3 treatment, give a second dipping in 40 ppm GA3.4. The field should have sufficient moisture during girdling and at least 3 weeks after that.5. Harvest the crop when it attain the requisite T S S content.Two foliar sprays of potassium sulphate @ 1.5%, first one week after fruit set and second at color break stage, improve the quality and color of Perlette grapes.
Maturity and Harvesting
Grapes should be harvested only when they are fully ripe. Grapes need repeated picking to harvest the entire crop because they do not ripen at one time. Taste is the most valuable indication of the ripeness of the bunch. If berries near the tip are good to eat, the entire bunch is ripe for picking. Taste of berries supplemented with color, T S S and sugar-acid ratio gives a fair idea about the time of harvesting. Ripe grape bunches should be carefully clipped with scissors. The bunch should be picked close to the cane so that there should be long cluster stem for handling of bunches during picking, packing, displaying and marketing of fruits. During handling,the natural bloom on berries should not be rubbed off. Harvesting should be done during the cooler part of the day. Bunches should not be exposed directly to the sun after harvesting.
Post- Harvest Handling and Marketing
Unripe, over-ripe, small, mis-shapen, sun-burnt, decayed, soft and bruised berries should be trimmed. Bunches should be graded according to the fruit maturity and size. Different grades should be packed in different containers. For nearby markets, mulberry or bamboo baskets can be used whereas, for distant markets C F B boxes of 2-4 kg capacity should be used.Grapes packed in LDPE bag with single sheet of sulphur dioxide generating pad and kept in Corrugated Fiber Board (CFB) boxes can be stored for 30 days at 0-2'C temperature and 90-95% relative humidity with acceptable quality.The Flame Seedless grapes harvested at optimum maturity with firm berries having light purple color and packed in ventilated CFB boxes (4 kg) lined with polythene film containing one sheet of grape guard can be stored with acceptable quality for 45 days at 0-2'C and 90-95% R.H.
Preparation of Red Wine and Vinegar
Red wine with 10.5 percent (v/v) ethanol can be prepared from Punjab Purple grapes by alcoholic fermentation of must (juice+skin)using indigenous yeast Saccharomyces cerevisiae G with a fermentation efficiency of 90.4 percent. With this developed small scale (5 liters) technology, wine recovery of 62.4 percent (v/v) can be achieved. Production technology of grape vinegar from Perlette at 5L scale has been standardized and recommended. This technology will provide an alternative use of Perlette grapes. It is a fruit based natural vinegar with properties of grapes and vinegar blended together. Grape vinegar has shelf life of 2 years.
Water berry: It is characterized by drying of berries usually at the tip of the clusters. Drying may also be scattered within cluster during May and June. The berries look like small cellophane bags,half filled with sap and remain hanging from the clusters. This disorder is caused by over bearing, excessive application of nitrogenous fertilizers and excessive irrigation or water stress. Apply judicious irrigation and nitrogenous fertilizers to overcome this problem.