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The papaya (Carica papaya L.) belongs to the family Caricaceae. It is an important fruit of tropical and sub-tropical regions of the world. It is the most important plant in the home gardens, and where green papaya is also used as a vegetable. Ripe fruits are eaten as dessert, which is available throughout the year.

Papaya is native to West Indies and Central America (Mexico). It is a common fruit in nearly all parts of tropical and sub-tropical world. It is abundantly grown in India, Sri Lanka, Bangladesh, South America, Pakistan, Australia, Mexico, Costa Rica, Hawaii, Kenya, Taiwan, Puerto Rica, Peru, USA, Philippines. It was introduced in India in 16^th Century. In India it is mainly cultivated in Kerala, Assam, Bihar Uttar Pradesh, Gujarat, Tamil Nadu and West Bengal.

Cultivars: Honey Dew, Coorg Honey Dew, Washingtan, Pusa Delicious, Pusa Majesty, Pusa Dwarf, Pusa Giant, Co. 1 to Co. 7, Arka Surya, Arka Prabhat, Pusa Nanha, Pink Flesh Sweet, Pant 1, Sunrise Solo and Taiwan Red Lady, are the most popular varieties under cultivation in India.

Papaya is one of the fruit crops grown both commercially as well as a backyard crop. Papaya was mainly a backyard crop till recently. It emerged as a main commercial crop during the last decade, because of the high nutritive value. It is a rich source of Vitamin A (2020 I.U), Vitamin B1 (40 mg), Vitamin C (46mg), protein (0.5%) and mineral matters (0.4%). Ripe papaya is a favourite breakfast and dessert fruit available yearround. It is used for making fruit salads, refreshing drinks, jams, jelly, marmalade, candies and crystallized fruits. Green fruits are pickled or cooked as vegetable. Carpine, an alkaloid present in papaya, can be used as a heart depressant, amoebicide and diuretic. It is also grown for the extraction of papain, a proteolytic enzyme present in the latex, collected mainly from the green fruit. In 1875, T. P. Lucas, a British physician discovered the medicinal value of papaya and started a hospital in Brisbane, to treat patients solely with papaya. The people in Papua New Guinea use papaya for the skin and to treat rashes or sunburn or, with repeated applications, to remove the brown spots of aging. They also say that if you put papaya into the compost pile, they grow especially large! Natives in the Pacific Islands use all parts of the papaya tree for medicinal purposes — leaves, skin, seeds, bark, roots, flowers and of course, the fruit. South American women massage their breasts with thin slices of green papaya to stimulate the milk glands. Eating the fruit provides energy and nutrients for both herself and the baby. Papaya bark is used as a toothache remedy and the flowers in teas, to treat bronchial infections. For centuries, teas from the roots were used to expel parasites and to alleviate bleeding, kidney colic, and jaundice.

1. Stem rot / Foot rot/Collar rot
Diagnostic Symptoms
• The appearance of water-soaked spots on the stem close to ground level is what characterizes it.
• The tissues degrade as a result of the fast enlargement of these patches, girdling the stem and turning it dark brown or black.
• Strong winds cause these afflicted plants to topple over and eventually die.
• If the disease attack is not too severe, the plants will still be stunted and only one side of the stem will decay.
• If fruit develops, it is deformed and withered.
• The plant eventually dies (Fig.1).
Etiology
• Pathogen: Pythium aphanidermatum.
• Mycelium is colorless, slender, coenocytic, profusely branching and rapidly growing mostly intracellularly.
• Sporangia terminal or intercalary produce a vesicle at the end of hyphal branch.
• Zoospores biflagellate and reniform.

Genus : Carica 
Species : papaya L.
Family : Caricaceae
Chromosome No. : 2n = 18, 36

The papaya plant is a huge/giant herbaceous plant and in general appearance looks more like a palm although there exists no botanical relationship between them. Papaya is said to be native of tropical America where it is a common fruit however the exact place of its origin is not well determined. Presently the plant is widely distributed and is abundant in India, Sri Lanka and many other countries of the Malaya Archipelago, Hawaii. Papaya fruit as well as all plant parts contain a milky sap called papain. This enzyme resembles animal pepsin in its digestive action and has become an important article of commerce, is utilized in the clarification of beer and its digestive action too has been very well recognized. Another remarkable papaya character is the irregularity which it presents in the sex distribution. Being dioecious, staminate and pistillate flowers are produced on different plants, besides a number of intermediate form have also been observed.

The papaya, papaw or pawpaw is the fruit of the plant Carica papaya, commonly known as ‘melon tree’ in the genus Carica. It is native to the tropics of the America. This highly loved tropical fruit was reputably called “The Fruit of the Angels” by Christopher Columbus. Papaya is considered powerhouse of nutrients as it is rich in anti-oxidants, vitamins viz. A, B, C, minerals like potassium and magnesium and fiber. Together, these nutrients needed for function of a healthy immune system, promote the health of the cardiovascular system and also provide protection against colon cancer. In addition, papaya contains the digestive enzyme, papain, which helps in digestion and is widely used in industry for various purposes. 

Yellow pigment in papaya - Caricaxanthin

• The enzyme present in dried latex of papaya (papain) is pepsin.
• Frost is the most limiting factor for papaya cultivation in North India.
• Papaya is a polygamous plant. –
• 20 seeds of papaya weigh one gram
• Carpine obtained from papaya is used as a diuretic and heart stimulant.
• 10% male plants are planted wherein dioecious varieties are calculated.
• Papaya plants are extremely susceptible to waterlogging.
• Papaya is thermosensitive crop.

  Carica candoamarcensis is scientific name for Mountain papaya.

• Papaya has the highest production after banana.
• Sunrise Solo type papaya produces no male plants.

Papaya, Carica papaya is a fruit mainly grown in tropical and sub-tropical regions. India is top most producer of papaya in the world and accounts for around 45 per cent of the total papaya production in the world. In India, the main cultivation of papaya is in the states of Telangana, Andhra Pradesh, Orissa, West Bengal, Kerala, Karnataka, Madhya Pradesh, Tamil Nadu and Gujarat. In north, due to frost problem, the cultivation is fruitful only in frost free areas as this fruit crop is highly frost sensitive. Few insect pests are of major concern in the cultivation of papaya, the description of which is given hereunder:

Papaya mealy bug, Paracoccus marginatus Williams & Granara de Willink (Pseudococcidae: Hemiptera)

It is an invasive pest believed to be a native of Mexico or Central America. In India, it was first reported in Tamil Nadu during July 2008 infesting papaya and later it spread to number of fruit, vegetables and ornamental crops in many states. The eggs are grain like and greenish yellow. The nymphs as well as adult is yellow but appears white due to waxy coating over its body

Fruit flies : Bactrocera cucurbitae,Toxotrypana curvicauda : Tephritidae

The fruit flies lay eggs on maturing fruits. The emerging maggots feed in the fruit pulp, causing rotting of the fruits.

AK grasshopper: Poekilocerus pictus: Acrididae

Nymphs and adults of the AK grass hopper feed on papaya leaves and tender bark.  Maximum damage is done during July-August in North India.
 
Aphids : Aphis gossypii, Myzus persicae: Aphididae

Nymphs and adult aphids suck sap from leaves. They are more important as a vector of papaya mosaic virus disease. The affected trees die in an year or two.

Origin and history: Papaya has long been known as wonder fruit of the tropics and is one of the five major fruit crops of tropical world, papaya fruits throughout the year and a remunerative fruit crop which is grown in almost every part of the country. It gives maximum yield per unit and income next to banana. It is generally grown as fruit plant in kitchen garden, home garden or nutrition garden and later as commercial fruit. It is also planted as a filler plant in a fruit orchard. India is the second largest producer of papaya in the world after Brazil. It is a fruit native to tropical America and commercially grown in many parts of the world viz., Australia, Hawaii, Taiwan, Puerto Rico, Peru, Florida, Texas, California, South Africa, Pakistan, Bangladesh and India. In India, it was introduced by Portuguese in 1611. It is grown in Karnataka, Bihar, Kerala, Tamil Nadu, Assam, Gujarat, Maharastra, Andhra Pradesh, Madhya Pradesh etc.

Papaya (Carica papaya L.) has emerged from the status of a home garden plant to that of commercial orchards and is popular with the farmers because it is one of the few fruits which fruits throughout the year, give quick and high returns, requires less area per tree and adapts itself to diverse soil and climatic conditions. It is an important fruit of tropical and mild subtropical regions of the country. Though India is the leading producer of this fruit, the productivity (43.27 MT/ha) is below it’s potentially (100 t/ ha). In India, Andhra Pradesh, Gujarat, Karnataka, Madhya Pradesh and Maharashtra are important centres of its production.

Origin and Distribution

Papaya is native to tropical America, from Southern Mexico through the Andes of South America. It was spread to the south by Indians, and throughout the Caribbean with Spanish exploration. It was spread in 16^th century to other parts of the world. The Spanish also carried it to Europe and the Pacific Islands. By the mid 17th century, papaya was distributed pan tropically. Papaya was introduced to Hawaii in the 1800s, and Hawaii remains the only state in the USA to produce papaya commercially. Now it is grown in all tropical and sub-tropical countries like Australia, Hawaii, Taiwan, Puerto Rico, Peru, Florida, Pakistan, Bangladesh and India. It was introduced in India in 16^th century by Portuguese. There are leading producer countries in the world which are India, Brazil, Mexico, Indonesia, Dominican republic, Nigeria, Democratic republic of the congo, Cuba, Thailand and Venezuela (Bolivarian republic).

India, is the worldwide leading producer of papaya and its principal exportation market is focused on Gulf countries. The papaya cultivation in India was 138 with production 5989 (‘000 hectare production ‘000 metric tones) in 2017–18 and it was 146 with production 6096 (‘000 hectare production ‘000 metric tones) 2018–2019. At harvested area rank, Mexico is the fifth papaya harvester, with 17,500 hectares. The maximum area in Gujarat followed by Andhra Pradesh, Kerala, and Chhattisgarh; and production is maximum in Andhra Pradesh followed by Gujarat and Karnataka, Anony, 2019.

3.1. Introduction

Paper and paper-based packaging is the traditional form of packaging used for various food products due to its various advantageous characteristics. It is less expensive, flexible, lightweight, durable, recyclable and available in various shapes, sizes and colour to meet customer needs. Hence it occupies a vast market in food packaging from primary (i.e., packaging which is first used after manufacture) to secondary (i.e. processing aids of primary packages) packaging and the production of paper has doubled in the last three decades. In the year 2020, china was the leading producer for paper and paper based packaging followed by USA and Japan (Figure 1).

Paper chromatography (P.C.) is the easiest to perform and requires simple and ordinary apparatus. It easily provides qualitative information since components of a mixture can be separated based on their mobilities or molecular weights. It also can provide quantitative information if some special attention and calculation procedures are followed. Paper chromatography is a technique that involves placing a small dot or line of sample solution on to a strip of chromatography paper. The paper is placed in a jar containing a shallow layer of solvent and sealed. As the solvent rises through the paper, it meets the sample mixture, which starts to travel up the paper with the solvent. This paper is made of cellulose, a polar substance, and the compounds within the mixture travel farther if they are non-polar. More polar substances bond with the cellulose paper more quickly, and therefore do not travel as far.

Soils become acidic due to natural  and artificial (anthropogenic) reasons. The natural reasons include their origin from acidic parent materials namely granite, rhyolite, pegmatite and dacite etc. and areas under high rainfall  (rainfall  exceeding evapotranspiration) removing  basic cations through leaching and erosion particularly in coarse textured soils with undulated, hilly and sloping topography. Under natural condition, accumulation of organic matter and its decomposition also releases organic acids into the soil system, turning soils  acidic. The anthropogenic factors    responsible for turning soils  acidic,  are (i) removal of basic cations through crop cultivation, (ii) continuous use of acid forming fertilizers and (iii) acid rain in industrial areas.

Paphiopedilum is a genus of the orchid subfamily Cypripedioideae and family Orchidaceae. It is derived from Paphos and ancient Greek word “pedilon” means “slipper”. Paphiopedilums are often called “slipper orchids” because of their unique pouch. The pouch traps insects seeking nectar and to leave again they have to climb up past the staminode, behind which they collect or deposit pollinia. Paphiopedilum has a highly ornamental value being the treasure of Orchidaceae. They are easily grown as houseplants and their care is very similar to African Violets.

ORIGIN AND DISTRIBUTION

The genus name Paphiopedilum was established by Ernst Hugo Heinrich Pfitzer in 1886. Ironically, no paphiopedilum occurs on Cyprus- at least not as the genus is understood today. But it was long mixed up with its holarctic relative Cypripedium, which indeed grows in the Mediterranean region. Paphiopedilum was finally decided to be a valid taxon in 1959, but its use has become restricted to eastern Asian species. The genus is native to Indo-Malaysia (South China, Southeast Asia and the Pacific Islands) and India. Paphiopedilum armeniacum is found from China (west Yunnan province) to northern Myanmar. It occurs at 1,600 to 2,000 metres above sea level. It is found growing on limestone hills, in semi-shaded deciduous forest, usually on cliffs above rivers.

SPECIES

Over fifty species of Paphiopedilum have been discovered in the far east from the higher, cooler elevations of the Himalayas, across to China and Southeast Asia and down to the warmer, sea-level regions of Malaysia, Indonesia and the Philippines (Hawkes, 1965). Most species, like Paphiopedilum callosum are terrestrial in nature growing under the shaded and moist conditions of the forest floor (Fitch, 1982). Some species, such as Paphiopedilum niveum are lithophytic found in colonies on the coastal rock formations of the Malaysian islands (Fitch, 1982a). While a few of the larger strap-leaf Paphiopedilum species exposed to the higher light conditions found in their loftier habitats. Paphiopedilum philippinense var. roebelenii and Paphiopedilum lowii provide a strong contrast to such as Paph. lowii, are usually epiphytic Paphiopedilum charlesworthii previously described and serve to illustrate the extent of variation in both plant and flower habit within this genus. Unlike the single-flowered spikes of Paphiopedilum charlesworthii, which are usually around 15 cm tall, those of Paph. philippinense var. roebelenii and Paph. lowii can bear up to a half-dozen flowers and can measure 60 cm or more in length. Paphiopedilums with this kind of flowering habit are referred to as multifloral paphiopedilums (Batchelor). The plants themselves can be quite large particularly in the case of Paphiopedilum lowii, where individual leaves are often well over 30 cm long, though narrow.

Paphiopedilum is a genus of the orchid subfamily Cypripedioideae  and family Orchidaceae. It is derived from Paphos and ancient Greek word “pedilon” means “slipper”. Paphiopedilums are often called “slipper orchids” because of their unique pouch. The pouch traps insects seeking nectar and to leave again they have to climb up past the staminode, behind which they collect or deposit pollinia. Paphiopedilum has a highly ornamental value being the treasure of Orchidaceae. They are easily grown as houseplants and their care is very similar to African Violets.

9.1. Origin and distribution

• Originate from North America, in particular Central Mexico.

9.2. Economic importance

• Paprika contains capsanthin and capsorubin.

• Used to season and color rice, stews, and soups, such as goulash, and in the preparation of sausages, mixed with meats and other spices.

• There are six paprika American, Bulgarian, Hungarian, Moroccan, Spanish and Yugoslavian.

• In US, sprinkled raw on foods as a garnish.

9.3. Types and varieties

• Types of bell pepper

? Green pepper: Can be a little bitter, but it is very useful, such a fruit reduces the level of cholesterol in the blood. And it has the least calories.

? Red pepper: Is the sweetest and contains the most vitamin C.

? Orange pepper: It is also very tasty, but it contains slightly less vitamin C than red.

Introduction

Enough literature is available to understand the concept of extension. But are there any efforts to understand the in-tensions of ex-tension? Why should we emphasize on inner tensions of extension? to be a successful extension professional for bringing about the desirable changes in the behaviour of stakeholders, we need to understand the inner-tensions of extension in addition to the concept of extension.

Since inception of extension services, the model adopted for transfer of technology was dominated Technology, wherein the core emphasis was on the transfer of technology. The end product was the partial adoption of the technology or non-adoption of the technology. Learning from the experiences, modifications were made in the model and came out with extension mediated technology transfer system, wherein the technology is inseparable component of extension, which was combined with the human element or the societal element. The approaches adopted by different models of extension service delivery were also diverse.

The first model of extension service delivery the Public extension system or the Ministry of Agriculture, which delivers the extension services in the form of a systems approach. The relationship with the farmers or the end users is ‘take it or leave it’. Whether the receivers are gaining it or not, whether they do understand it or not, ultimately we are transferring it, and are ending it with the target oriented approach.

Parakeratosis is a pathological condition characterized by the abnormal keratinization of epithelial tissues. In ruminants, particularly cattle, buffaloes, sheep, and goats, parakeratosis primarily affects the rumen epithelium. This condition is often associated with dietary imbalances, particularly in animals fed high-concentrate, low-fibre diets. Left unchecked, it can lead to significant health issues, including impaired nutrient absorption, secondary infections, and reduced productivity.
The rumen is a vital component of the ruminant digestive system, serving as a fermentation chamber where microbes break down fibrous plant material into volatile fatty acids (VFAs), which are absorbed and used as energy. The rumen wall consists of four layers: the stratum basale, stratum spinosum, stratum granulosum, and stratum corneum. The stratum corneum is the outermost layer, consisting of keratinized epithelial cells that protect the underlying tissues. Under normal conditions, the keratinization of the rumen epithelium is tightly regulated. However, certain dietary and environmental factors can disrupt this process, leading to parakeratosis. Nutritional management is a cornerstone of both the prevention and treatment of parakeratosis. Proper dietary practices ensure the maintenance of a healthy rumen environment, optimal microbial activity, and the prevention of epithelial damage. The link between diet and parakeratosis is well established.

Aim: Perform the parallel operation of single-phase transformer and observe the load sharing of each transformer.

A power transformer is one of the most vital and an equally expensive component in a power system. It may so happen that, over time, due to load growth in its service area, an existing transformer may not be able to withstand the demand during peak-hours without exceeding its long-term MVA rating. Operating a transformer in such a fashion would cause overheating and degrade its expected life. In most cases, instead of commissioning an entirely new higher capacity unit, a more viable alternative exists in adding a smaller unit in parallel to complement the existing one. In other words, a new smaller capacity transformer can now be connected in parallel to the existing one such that the two shares a large peak load in a specific proportion and the one operating near limits is relieved of the burden.

Hypothesis testing enables researchers to determine whether apparent climatic or agricultural differences are statistically meaningful. Parametric tests are appropriate when data satisfy assumptions such as normality and homogeneity, whereas non-parametric tests are useful for irregular, ranked or non-normally distributed observations. This chapter discusses commonly used procedures, assumptions, selection criteria and interpretation. Applications include comparing weather conditions, evaluating crop responses, detecting rainfall or temperature trends and assessing environmental change. Methods such as t-tests, Mann-Whitney, Wilcoxon, Kruskal-Wallis and Mann-Kendall tests are relevant to agroclimatic research. Appropriate test selection improves analytical reliability and supports evidence-based decisions concerning climate variability, crop performance and agricultural adaptation.