Guava (Psidium guajava L.)
Guava (Psidium guajava L.) is a fruit native to the American tropics; it is also known as guayabo, guara, arrayana, and luma in some regions.
Introduction:
Guava (P. guajava L.) is one of the world’s most common fruits and belongs to the family Myrtaceae. It is considered as “the fruit of the poor man,” or “the apple of the tropics” due to high nutritional value and delicious taste. The major guava producing countries are Pakistan, South Africa, India, Brazil, Egypt, Mexico, Venezuela, and Columbia (Rawan et al., 2017). It grows on an area of 62.3 thousand hectares in Pakistan and produces a yield of 512.3 thousand tons of fruits annually (Hassan et al., 2012). Guava fruit is extremely nutritious having high amounts of vitamins A, B1 (Thiamine), B2 (Riboflavin), and C (Ascorbic acid). The vitamin C content of guava fruit is 2–5 times that of citrus fruit (Singh, 2005). This fruit also contains a significant amount of citric, lactic, malic, oxalic, and acetic acids (Rahman et al., 2003). Fruit maturity is an important aspect for table purpose and processing due to better chemical and physical property of the fruit.
Bangkok Red:
Red Bangkok guava (Ripe Red, Psidium guajava) is breeding plant between pomegranate Siam guava tree and Pansrithong guava tree.This trunk of hybrid is red. The upper part of leave is green-black, but the lower part is red-brown. The flower is red-pink and very beautiful. The young fruit is brown-black. The ripe fruit is brown-red. The interior of fruit is red with sweet smack. Its shape looks like Vietnam guava fruit.
Propagation
Manga et al. (2017) in guava reported that minimum days for root initiation (84 days), maximum number of roots (12.10), higher rooting percentage (33.33) and survival percentage (100.00) in layers prepared in the month of August applied with IBA - 4000 ppm. The highest number of sprouts (8.25), number of leaves (22.64) and shoot length (59.00 cm) of these layers were observed 90 days after separation from the mother plant, when the layers were placed in a shade house for hardening. The layers were then treated with IBA–3000 ppm prepared in August month.
Increase yield and quality:
Furthermore, both GA3 and B also interacted with other nutrients like N, Mg, and Zn, which contributed to an improvement in the yield and quality of guava because of an additive effect
Polyploidy:
Polyploid plants are noticeably superior in horticultural traits than diploid plants and could be utilized in future breeding programs.
A total of 5400 seeds of guava cv. ‘Arka Kiran’ were treated with colchicine at different concentrations at 200 ppm GA3. Initially, the seeds were treated with GA3 for 2 h followed by water washing and treatment with the respective colchicine concentrations after which they were sown in coco-peat media.
Postharvest storage:
Guava (Psidium guajava L.) is a climacteric fruit high in vitamin C and consumed mainly fresh. . One factor limiting its marketing and exporting is its short postharvest life, 5-7 days at 25°C and 15 days at 10°C, which limits its export to distant markets (González et al., 2002). The accelerated loss of firmness causes poor visual appearance and low mechanical resistance. Postharvest calcium applications help maintain fruit firmness due to its ability to strengthen bonds between the polysaccharides of the cell wall; also reduces weight loss and inhibits the production and action of ethylene, and helps maintain the stability and functionality of cell membranes (rsion of ‘Allahabad Safeda’ guava fruit in 2% CaCl2 solution and stored 4 weeks at 6°C and 90-95% RH showed less weight loss, better firmness and better visual quality.Fruits of guava Psidium guajava L. ‘Media China’ harvest at yellow-green maturity in a commercial orchard .These are pre-cooled 10 min at 5°C. Five batches of 45 fruits were infiltrated under vacuum (10 min at 10 in Hg) with glycine-calcium (Ca-Metalosate®) solutions 0.08 M). After treatment, the fruit drained and stored at 20 days 10°C and 90% RH.
INFLUENCE OF 1-METHYLCYCLOPROPENE ON PHYSICO-CHEMICAL PROPERTIES OF ‘GOLA’ AND ‘SURAHI’ GUAVA (Psidium guajava L.) UNDER AIR STORAGE
MCP to be effective, intermediate dose levels of 1-MCP (500 nL·L-1 ) are best to maintain the quality of guava during storage. Moreover, cultivars responded differently to 1-MCP and cv. Surahi maintained its keeping quality better compared to cv. Gola.
Treatment plan: prepare Stock solution of 1-MCP by taking known quantity (in mg) of 1-MCP powder in micro centrifuge plastic tube having cap. After weighing, 1-2 drops of water at room temperature were added in micro centrifuge tube and shake vigorously for 3-5 times after closing the cap. Cap of centrifuge tube was opened in 600 mL glass bottles having rubber septum. After 1 h of 1-MCP release, working concentrations were taken with the help of syringe at STP. Application of 1-MCP was carried out in air tight plastic bucket (70-L) by focusing the free air space in the bucket. Fruits are exposed to 800 nL·L-1 1-MCP for 12 h at 15°C. After exposure to 1-MCP, fruits removed from the bucket, placed in a pre-clean plastic box, and loosely wrapped with 0.02 mm thick polyethylene sheet.