Description
A small tree to 33 ft (10 in) high, with spreading branches, the guava is easy to recognize because of its smooth, thin, copper-colored bark that flakes off, showing the greenish layer beneath; and also because of the attractive, “bony” aspect of its trunk which may in time attain a diameter of 10 in (25 cm). Young twigs are quadrangular and downy. The leaves, aromatic when crushed, are evergreen, opposite, short-petioled, oval or oblong-elliptic, somewhat irregular in outline; 2 3/4 to 6 in (7-15 cm) long, I ‘A to 2 in (3-5 cm) wide, leathery, with conspicuous parallel veins, and more or less downy on the underside. Faintly fragrant, the white flowers, borne singly or in small clusters in the leaf axils, are 1 in (2.5 cm) wide, with 4 or 5 white petals which are quickly shed, and a prominent tuft of perhaps 250 white stamens tipped with pale-yellow anthers.
The fruit, exuding a strong, sweet, musky odour when ripe, may be round, ovoid, or pear-shaped, 2 to 4 in (5-10 cm) long, with 4 or 5 protruding floral remnants (sepals) at the apex; and thin, light-yellow skin, frequently blushed with pink. Next to the skin is a layer of somewhat granular flesh, 1/8 to 1/2 in (3-12.5 mm) thick, white, yellowish, light- or dark-pink, or near-red, juicy, acid, sub acid, or sweet and flavourful. The central pulp, concolorous or slightly darker in tone, is juicy and normally filled with very hard, yellowish seeds, 1/8 in (3 min) long, though some rare types have soft, chewable seeds. Actual seed counts have ranged from 112 to 535 but some guavas are seedless or nearly so.
When immature and until a very short time before ripening, the fruit is green, hard, gummy within and very astringent. https://www.hort.purdue.edu/newcrop/morton/guava.html
Field Preparation
Forested areas should be cleared of all shrubs and trees and the ground ploughed in. In areas where the earth is extremely firm, deep cultivation using tractor tines is recommended to break up the subsoil. Drains have to be constructed where the water table is high.
The recommended planting distance is 15′ x 15′. This gives about 193 trees/acre. The field should be limed and the planting distance measured out before digging the holes. The holes should be at least 1.0 cu. ft. in size depending on the firmness of the soil. In planting very large acreages, tractor-operated augers should be used for digging the holes.
Soil and Climate
Guava can be grown in a wide range of soils, but does best in deep fertile and well-drained loams. It can tolerate a wide range of pH from 4.5 – 8.2. Waterlogging, however, adversely affects the growth. Although guava can tolerate drought conditions much better than other tropical fruits, an annually even distribution of 100 – 200 cm of rainfall is preferred for good growth. The tropical climate of Malaysia is considered excellent for guava cultivation.
http://rfcarchives.org.au/Next/Fruits/Guava/Guava2-84.htm
Variety
L-49 (Lucknow-49): It is prolific bearer, greenish yellow with milky white sweet pulp and rough surface. Shell is fairly thick, contains fairly soft few seeds in inner portion of pulp. Since the number of seeds is less, keeping quality is medium it is very popular in Maharashtra and Andhra Pradesh. It is suitable for table purpose and yields about 25t/ha.
Allahabad Safeda: This is the most famous variety gown in Uttar Pradesh for table purpose. Tree is medium in height (5.8-6.5m) with vigorous branching and dense foliage. Fruits are medium in size (180g), round in shape with few seeds. Fruit is white fleshed with good keeping quality.
Banarasi: The variety attains a height of 4.0 to 5.5 m with a broad crown and fruits are round, light-yellow in colour. It is mainly cultivated for table purpose.
Chittidar: The Chittidar is similar to the Safeda except that it has many pinkish red dots of the size of a pinhead on the surface of the fruit.
Harijha: The variety attains a height of about 3.5 to 4.5 m and is sparsely branched. Fruits are round,greenishyellow in colour with a sweet taste.
Red Fleshed: Tree attains 3-5m height. The branches are spreading with roundish oval fruit, which has yellowish skin with pink colour flesh.
Arka Mridula: This varriety is a selection from open pollinated seedlings of Allahabad Safeda. Plants are semi-tall in nature and spreading. Fruits are round in shape and weigh about 180g. Skin is yellow in colour and smooth. Flesh is white in colour. The TSS is around 12OBrix. Fruits are soft seeded and have a good keeping quality. It is good for processing due to high contents of pectin (1.041%).
http://agropedia.iitk.ac.in/content/guava-varieties-its-characteristics
The table below shows some of the promising varieties is given in Table 1.
| Variety | Fruit size | Appearance | Flesh colour | Seed | Taste | Products |
| GU 3 | large | Oblate, grooved | white | abundant | non-acidic | fresh fruit, juice |
| GU 4 | medium | elongate, smooth | white | abundant | non-acidic | fresh fruit, juice |
| GU 5 | large | smooth, round | red | abundant | acidic | juice |
| Bentong seedless | medium | Irregular | white | absent | non-acidic | fresh fruit, canned slices |
http://rfcarchives.org.au/Next/Fruits/Guava/Guava2-84.htm
Guava Planting
In spite of substantial increase in area and production, there is an ample scope for area expansion; due to its precocious and prolific bearing habit, which in turn ensures high returns to the guava growers. True to the type planting material is the most vital component of area expansion.
Guava can be propagated by seeds as well as by vegetative means. However, vegetative propagation methods are preferred over the seed propagation because in spite of being self-pollinated crop, cross pollination is common in guava.
Seed propagation cannot maintain the genetic purity and results in large variation in the seedling population because of segregation and recombination of characters during sexual reproduction. Variation in the plants affects the fruit quality, shape, size and yield.
Further seedling plants take 6-7 years to come into bearing stage. Seeds may be employed to raise rootstocks for grafting and budding.
- Seedling Raising for Rootstock
Seedlings can be raised in the nursery beds or in polythene bags, however raising rootstocks in polyethylene bags is recommended due to better establishment of plants in the field on account of undisturbed tap root system. Moreover, rootstock raising in polyethylene bags is cost effective as it saves labour in weeding, watering, shifting and lifting of plants.
For raising seedlings extract fresh seeds from the fully matured ripe fruits and wash them thoroughly to remove the pulpy material clinging to the seeds. Guava seeds take long time to germinate because of a hard coating over the endocarp. Therefore, it is necessary to soak seeds in water for 12 hrs or in hydrochloric acid/ strong sulphuric acid for 3-5 minutes prior to sowing to facilitate their germination.
Seed viability declines very quickly after extraction from fruits therefore, seeds must be sown immediately after their extraction. Dip guava seeds in captan / thiram (0.2%) for 2 minutes before sowing for the management of damping off of seedlings. If the damping-off occurs after seedling emergence, both the seedlings and the media should be treated with copper oxychloride (0.3%).
Sow guava seeds in polyethylene bags (20×10 cm) filled with soil, sand and farmyard manures in 3:1:1 ratio. Soon after sowing of the seed, cover the polyethylene bags with 100 micron (400 gauge) white polyethylene sheet.
During winter months, the polyethylene mulch conserves heat and create conducive environment (microclimate) for rapid germination and early establishment of seedlings. Seed covered with polyethylene sheet gives as high as 95-97 per cent success within three weeks. These seedlings become ready in 8 to 12 months for budding or grafting.
- Vegetative propagation for true to the type planting material
True to the type plants can be obtained through layering, grafting, stooling and budding. Guava is hard to root therefore; its propagation by cuttings under ordinary conditions is not successful. It is only successful under intermittent mist conditions with the aid of rooting hormones like IBA and NAA. Hence, propagation through cuttings is not generally followed in guava.
- Air layering
Air layering is also known as ‘goottee’ which is mainly practiced during rainy season (June to September) because of high rooting and survival of layers (80-85%). For air layering 1-year-old branches of 1 to 1.5 m length are selected.
A ring of bark of 2.5 to 3.0 cm long is removed from 45 cm away from the tip. For better rooting IBA (root promoting plant growth hormone) @ 4000-5000 ppm is applied at the upper cut end of girdled area. The girdled area is covered with moist sphagnum moss and wrapped with polythene tape. Rooting starts within 3-5 weeks.
After 6 to 8 weeks when sufficient roots are visible through the transparent tape, the layer is removed from the branch by means of cutting the stem below the girdled area in stages.
The polythene film is removed from the finally severed rooted stem and some of the top is headed back which is then potted and kept in the shade until new leaves appear. When the new flushes are produced, the plants can be transplanted in the field. Different steps followed in layering are shown in Fig.1.
| a.Removal of bark ring | b. Application of root promoting plant growth regulator | c. Covering of girdled area with moist moss | d. Layered branch |
| e. Detached air layered twig | f. Layered twig with developed roots | g. Potting of layer | h. Plants ready for planting |
Fig.1. Layering steps in guava.
- Grafting in Guava
Grafting is practiced to take the advantage of well-developed root system of the rootstock. In guava it can be done by two ways: inarching and wedge grafting.
- Approach grafting/Inarching:
Inarching or approach grafting is the oldest technique employed in many guava growing areas. This method yields very high success (85 to 95%) during rainy season.
In this method of propagation, a thin slice of bark about 2.5-3 inches in length and about 1/3 inch in thickness at a height of 15-20 cm above the ground level is removed from the rootstock with sharp knife. A similar cut is made in the branch of mother plant to be used as scion.
The cut portions of both rootstock and scion are brought together and tied firmly with the help of grafting tape. After two months, stock above and scion below the union are cut gradually. Suckers sprouting from the rootstock are also removed. Inarching in guava is shown in Fig. 2.
| a.Removal of slice of Bark | b. Tied polythene potted rootstock with ground support of bricks | c. Polythene potted rootstock tied to the mother plant without any ground support |
Fig.2. Inarching in guava.
- Wedge grafting:
The technique involves growing of seedlings in polyethylene bags, grafting, capping and hardening of grafts. Seedlings are raised for rootstocks in the nursery for approximately 6 to 8 months. When the stem diameter of seedling is of pencil thickness (0.5-1.0 cm) they are chosen for wedge grafting.
In this technique, proper selection and preparation of scion sticks is very important for obtaining higher success. 15-20 cm long shoots (3-4 months old) with 3-4 healthy buds and of pencil thickness should be selected for grafting.
Selected scion shoots are defoliated on the mother plant, about a week prior to detaching. At the same time, the apical growing portion of selected shoot is also beheaded. This helps in forcing the dormant buds to swell. In this way, the buds on the scion are ready to start sprouting at the time of grafting.
This treatment is essential for high success of grafts. After selection of the scion, rootstock (seedling) is headed back by retaining 15-20 cm long stem above the soil level in the polyethylene bag. The beheaded rootstock is split to about 4.0 – 4.5 cm deep through the centre of the stem with grafting knife.
A wedge shaped cut, slanting from both the sides (4.0 – 4.5 cm long) is made on the lower side of the scion shoot. The scion stick is then inserted into the split of the stock and pressed properly so that cambium tissues of rootstock and scion stick should come in contact with each other. Care must be exercised to match the cambium layer of the stock and scion along with full length of each component.
The union is then tied with the help of 150 gauge polyethylene strip, 2 cm in width and 25 – 30 cm in length. Immediately after grafting, the graft is covered by 2.5 x 18.0 cm long white polyethylene cap which is tied with rubber band at the lower end.
The scion starts sprouting after 10 to 12 days. The cap is removed after 25 days in the evening hours. The grafts are transferred to net house for hardening. Different steps followed in wedge grafting are shown in Fig.3.
| a. Rootstock | b. Heading back | c. Cut making | d. Grafting |
Fig.3. Wedge grafting in guava
III. Stooling in Guava
It is the easiest and cheapest method of guava propagation which has been standardized at Indian Agricultural Research Institute (IARI), New Delhi.
In this method plants are headed back to ground and shoots are allowed to develop on the beheaded stumps. When shoots attain a size of 20-25 cm, these are girdled at the base by removing a bark ring of 2- 2.5 cm.
Indole Butyric acid (IBA) @ 2,500 ppm in lanolin is applied to the upper portion of the girdled shoots and shoots are left open for 2-3 cm days after IBA application. These shoots are covered/ mounded with soil to encourage rooting in the stools.
After 6-8 weeks, the roots are fully developed in the shoots and these shoots can be separated and planted in nursery. The shoots are headed back to maintain the root and shoot balance before planting in the nursery.
Before separating the stools, a light irrigation should be given if soil is dry. After separating the shoots apply ample quantity of manures and fertilizers and level the field. Stooling can be done twice a year (spring and rainy season) and in this way, one can get 30-40 stools per mother plant per year.
The stooling of a mother stool can be done for many years.
- Budding in Guava
In areas of high atmospheric humidity budding could be practiced. Different budding techniques could be employed like forkert, shield and patch. Patch budding can be done during May –June with 75-80 per cent success.
For patch budding seedlings of pencil thickness and about one year age with uniform active growth are selected. The trees from which buds are taken should be highly vegetative with lush succulent growth to permit easy separation of buds from the stem.
It is better to take swollen and unsprouted dormant buds from leaf axils of mature twigs of the scion variety. A patch of approximately 1-1.5 cm length with a bud is removed from the scion variety. Similarly, 1-1.5 cm long patch is removed from the rootstock and bud is fitted into the remaining portion on the stock seedling.
Bud should be fitted at a height of nearly 15-20 cm above the ground level. Polyethylene strip is used for keeping the buds close to the stock. When the bark adheres tightly to the wood, budding is usually successful.
After about 2-3 weeks of budding the polyethylene strip can be opened to examine the success. In successful cases, about one-third shoot of the rootstock can be removed for forcing the growth of buds. The remaining two-thirds can be removed after three weeks of the first cutting, leaving about 2-3 cm above the bud. http://www.krishisewa.com/articles/production-technology/346-guava-propagation.html
Management Practices
Manuring and Fertilization
Although guava is grown without application of any manure and fertilizer, it responds well in their application by giving higher yield and better quality fruit.
| FYM | Fertilizer requirement (g / tree) | |||
| Age of tree (Year) | (Kg/tree) | Urea | Diammonium Phosphate | Muriate of potash |
| 1 | 5 | 55 | 35 | 15 |
| 2 | 10 | 115 | 70 | 35 |
| 3 | 15 | 170 | 105 | 50 |
| 4 | 20 | 225 | 140 | 65 |
| 5 | 25 | 345 | 170 | 85 |
| 6 | 30 | 415 | 205 | 100 |
| 7 | 35 | 565 | 240 | 115 |
| 8 & onwards | 40 | 700 | 275 | 135 |
Note:- The fertilizer should be applied in two split doses i.e. 1st week of May for rainy season crop and 1st week of July for winter season crop.
Irrigation
Guava is mostly grown under rainfed conditions and irrigation is generally not practiced but wherever the irrigation is available, it should be given in summer and October/Novermber as it enhances the yield of guava tree by increasing fruit set.
Intercropping of Guava
Guava orchards may be intercropped with short growing leguminous crops like mash, moong, guar and vegetables during pre-bearing period.
Aftercare of Guava
Pre-harvest spray of calcium nitrate (2%) two weeks before harvest improve quality at the time of harvest of guava, whereas, the spray of 150 ppm silver nitrate at 5 weeks before harvest and another spray at three weeks after first spray increases the shelf life of guava satisfactorily upto 6 days at room temperature.
GA, 90 ppm, sprayed 30 days before harvest improves the fruit quality at harvest and also increases the shelf life of guava.
Crop regulation
The fruits produced in the rainy season are not of high quality and have poor shelf life. Spray 10 per cent urea or 600 ppm NAA during April-May when maximum flowers have opened.
This eliminates rainy season crop so that winter guava crop is heavy and of superior quality. One leaf pair pruning of guava plants in the first week of May offers an effective method for avoiding rainy season crop, resulting into more yield and better quality in winter season crop.
Pest and Diseases Management
Diseases
| Symptoms | Management |
| Fruit Rot (Phyotophthora nicotianae)
The disease starts at the styler end. Whitish cottony mass develops very fast as the fruit starts ripening and covers the entire fruit surface in few days. Humid weather favours the disease. The diseased fruit drops from the tree. |
Spray the tree with combination of fungicides metalaxyl + mancozeb (250 g/100 L water) or metalaxyl (100 g/100 L water) or fosetyl-al (300g/100 L water) as soon as the disease is observed, repeat sprays at 15 days interval. |
| Anthracnose/Die Back (Colletotrichum psidii)
Symptoms appear on the leaves, twigs, flowers and fruits. Necrotic grey lesions are formed on the leaves, twigs start drying from downwards. Floral infection may lead to mummification or symptoms appear on ripe fruits as circular, slightly sunken lesions with raised margins. Spots coalesce to form corky and hard lesions developing cracks in them. Symptoms on mature fruits appear as pinkish spots with sticky spore mass in the centre. |
i) Prune dead twigs, remove mummified fruits hanging on the trees and burn.
ii) Spray copper oxychloride (300g/100L water), mancozeb (250 g/100 L water) or captan (300 g/100L water) soon after pruning, repeat spray at 15 days interval after fruit set. iii) Bury deep in soil the diseased/rotten unmarketable fruits fallen on the ground. |
| Wilt (Fusarium oxysporum f.sp.psidii)
Browning and wilting of leaves, stem discolouration accompanied by death of the branches on one side. The whole plant, sometimes shows wilting symptoms and finally dies. The causal pathogen may sometimes appear on the stem. |
i) Prune/uproot the wilted plants and burn.
ii) Treat the soil with formaldehyde (1 formaldehyde; 7 water) or gypsum (2 kg/tree) to prevent further spread. iii) Severe pruning of diseased branches followed by soil drenching with carbendazim (100 g/100 L water) or metalaxyl + mancozeb (250g/100L water) or fosetyl-al (300g/100 L water) at an interval of three months. |
| Twig Blight and Canker (Cytospora chrysosperma)
The diseased plants show sick look, less foliage and blighted appearance. Canker appears on bud scars, wounds, twigs or in crotches. Embossed, globose and cankerous pimples appear on diseased twigs. Bark becomes loose with amber yellow exudates becoming horny on drying. The symptoms are quite pronounced under wet conditions. Stromatic fungal masses appear on the surface of diseased twigs. |
i) Scratch the dead bark alongwith some healthy portion. Burn the pruned dead twigs and disinfect the wound with Bordeaux paste or copper oxychloride paste.
ii) Spray the treated trees with copper oxychloride (300g/100L water) or carbendazim (100g/100L water or thiophanate methyl 100ml/100L water). Repeat sprays in March and June. iii) Remove severely infested trees and burn. |
| Collar Rot (Phytophothora sp., Sclerotium sp, Diplodia sp.)
Bark of the plant at collar region turns brown, cracks and some times peels off. |
Scrap the infected portion along with some healthy area and apply Bordeaux paste or copper oxychloride paste. Drench soil with metalaxyl + mancozeb (250g/100L water) or fostyl-al (100g/100L water). |
| Withe tip (Colletotrichum gloeosporioides)
The disease causes shedding of leaves and withering of tips of branches. On leaves, light green spots appear which later turn brown. Spots usually develop on the tips or margins of leaves. Black dots develop on leaves and twigs with pinkish ooze of spore mass. |
Prune off the diseased twigs and treat cut ends with Bordeaux paste. Give 1-2 follow up sprays with copper oxychloride (300g/100L water) or carbendazim (100g/100L water) or captan (200g/100L water) or thiophanate methyl (100ml/100L water). |
Insect Pest
| Guava Pests
Fruit Fly (Bactrocera dorsalis) Fruit flies deposit eggs in soft skin of ripening guava fruits. After hatching the maggots feed on the soft pulp as a result fruits start rotting and fall on the ground.
|
Management |
| i) Harvest fruits when they are still hard.
ii) Collect and destroy all fallen fruits. iii) Apply bait sprays in July-August at 10-15 days intervals (malathion50 EC 200 ml and gur 1 kg in 100 L water). |
|
| Fruit Borers (Virachola Isocrates)
(Dichochrosis punctiferalis) Larvae bore into the fruit and feed on the pulp of the fruit. |
Spray dimethoate 30 EC (0.03%) at marble stage of the fruit followed by 2ndspray at 4 weeks interval. |
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know how Guava is a medicine for modern diseases, you can also plan to get the book from here
http://www.krishisandesh.com/guava-cultivation-how-to-grow-guava/
Harvest and Post-Harvest Handling
Horticultural Maturity Indices
Harvest stage depends on variety and the stage at which fruit are to be eaten. If eaten green, fruit should be harvested at the mature, firm stage without any signs of ripening. Fruit to be consumed soft and ripe are harvested when they show some sign of color change from green to yellow, as well as initial softening. Later harvesting, when fruit are riper, can lead to a high number of fruit fly stings and later larvae in the flesh. SSC can vary from 3% in green fruit to > 10% in ripe fruit, and the TA from 0.2 to 1.5%; cultivars vary greatly in sweetness and acidity. There is seasonal variation in acidity in some cultivars.
Grades, Sizes, and Packaging
Commonly shipped in 4.5 kg (10 lb) single-layer cartons with foam sleeves or wrapping to prevent injury. Pre-Cooling Conditions Room-, forced-air, or hydro cooling should be used to about 10°C (50°F).
Optimum Storage Conditions
Mature green and partially ripe fruit can be held for 2 to 3 weeks at 8 to 10°C (46 to 50°F). Ripe, soft fruit can be held about 1 week at 5 to 8°C (41 to 46°F). RH of 90 to 95% is recommended (Kader 1999). Shelf-life is about 7 days when stored at 20°C (68°F). Controlled Atmospheres (CA) Consideration Short-term treatment (24 h) with 10% O2 + 5% CO2 before storage in air at 4°C (39°F) for 2 weeks’ delays colour development and reduces chilling injury, compared to fruit held in air (Bautista and Silva 1997). MAP in polyethylene bags and use of wax coatings delays ripening/softening. Skin blackening is a problem when some wax coatings are applied (McGuire and Hallman,1995).
Retail Outlet Display Considerations
Display chilled if fruit are fully ripe, or at 8 to 10°C (46 to 50°F) if green and if ripening is to be avoided. Chilling Sensitivity Symptoms include skin scald, pitting, and a failure to ripen if mature green or partially ripe when chilled. Browning of the flesh can occur. Decay incidence and severity increases with chilling injury. Ripe, soft fruit can be held at 5°C (41°F), as they are less sensitive to chilling injury. Ethylene Production and Sensitivity Rates vary from 1 to 20 μL kg-1 h-1 at 20°C and show a climacteric pattern of respiration. Rates vary with variety and stage of ripeness. Ripening is accelerated by exposure to ethylene (100 ppm, 24 h). Immature fruit do not ripen properly and develop a “gummy” texture (Reyes and Paull 1995). Respiration Rates See Table 1. To get mLkg-1 h-1, divide the mgkg-1 h-1 rate by 2.0 at 0°C (32°F), 1.9 at 10°C (50°F), and 1.8 at 20°C (68°F). To calculate heat production, multiply mg kg-1 h-1 by 220 to get BTU per ton per day or by 61 to get kcal per metric ton per day.
Physiological Disorders
Postharvest desiccation is a major problem, along with mechanical injury. Desiccation leads to a dull, yellow, sometimes wrinkled skin, while mechanical injury leads to browning that can extend into the flesh. Mechanically injured areas of the skin and flesh are very susceptible to decay. Postharvest Pathology Most diseases have pre-harvest origins and are sometimes latent infections such as anthracnose (Colletrotrichium gloeosporioides). Other diseases are associated with insect stings or mechanical damage, for example, Aspergillus rot (Aspergillus niger), Mucor rot (Mucor hyemalis), Phomopsis rot (Phomopsis destructum), and Rhizopus rot (Rhizopus stolonifer). Orchard sanitation and effective postharvest management, such as avoiding mechanical injury and promptly cooling, reduces incidence. Quarantine Issues Guava is a preferred host for fruit flies. Flies begin to sting fruit at the mature green color-break stage, but infestation is a problem as softening begins to occur. Heat treatments and irradiation both are potential disinfestation procedures. Suitability as Fresh-Cut Product Sliced mature green fruit are available in many South East Asian countries and are eaten like apple slices.
Specification
Colour: Chacteristics ripe Red Guava colour
Flavour: Typical ripe Red Guava flavour free from off flavour
Teste: Chacteristics ripe Guava teste
Aseptic: Available in 20 Kg Bag in Box packing as well as in 215/225/228 Kg Bag in Drum packing. Product can also be supplied in any other pack size as per customer requirement.
Frozen: Available in 1 kg frozen pouch/Bucket, in 200 kg bag in drum packing, frozen form can also be supplied in any other pack size as per customer requirement
Labelling: Every pack is labelled in accordance with current international legislations.
Aseptic: Eighteen months from the date of manufacturing when stored below 15 C. Product should be used quickly after opening the bag.
Frozen: Twenty-four months from the date of manufacturing when stored below -18°C.
http://www.jains.com/food/guava.htm
