eChapters

Synonyms: Circling disease, Meningoencephalitis, silage disease

It is an infectious fatal disease of wide range of animals and man characterized by encephalitis. It also causes abortion, endometritis and repeat breeding in farm animals. Historically, Listeria was first isolated in 1926 from a natural disease of rabbits characterized by mononuclear leucocytosis and therefore named as Bacillus monocytogenes by Murray and coworker at Cambridge. Later, Pierie who isolated similar bacillus from liver of gerbils in 1927 named it Listerella hepatolytica in honour of surgeon Joseph Lister and finally renamed it Listeria in 1940 due to taxonomic reasons.

Etiology: The disease is caused by L. monocytogenes. The genus Listeria consists of a group of Gm + bacteria of low G+C content closely related to Bacillus, Clostridium, Enterococcus, Streptococcus and Staphylococcus. Out of 6 species reported, only L. monocytogenes and L. ivanovii are considered virulent. Human cases of L. ivanovii infection are rare whereas L. monocytogenes is an important food borne pathogen. L. monocytogenes has been isolated from a variety of food products. Meat, poultry, dairy and vegetable products have been implicated as vehicles of listeriosis. The organism can be isolated from faeces and silage. The organism can be easily destroyed by ordinary disinfectants but may survive in soil and silage for a considerable period of time.

L. monocytogenes is small, coccoid with a tendency to occur in chains. It is aerobic or microaerophilic. It grows on ordinary media within a temperature range of 4-42°C. Growth is improved by addition of glucose, blood or liver extract. Colonies are β haemolytic on blood agar. It ferments glucose and salicin producing acid without gas. Lactose, maltose and sucrose are fermented slowly or not at all and mannitol is not fermented. It is catalase +. It shows tumbling motility when grown at 25°C but at 37°C is non-motile. It is because peritrichous flagella are produced by the bacillus optimally at 20-30°C but scantily or not at all at 37°C.

Litchi (Litchi chinensis Sonn.) is a popular subtropical evergreen fruit tree. The Litchi (lychee) is the most renowned of a group of edible fruits of the soap berry family, Sapindaceae. It is botanically designated Litchi chinensis Sonn. (Nephelium litchi Cambess) and widely known as litchi and regionally as lichi, lichee, laichi, leechee or lychee. Litchi is a tropical fruit tree native to southern China. It is also commonly found in Madagascar, India (Muzaffarpur), Bangladesh, Pakistan, southern Taiwan, northern Vietnam, Indonesia, Thailand, the Philippines, and Southern Africa. Great source of Vitamin C and potassium, it also contains phosphorous, calcium, magnesium and protein. The fruit is liked by everybody because of its excellent quality, attractive red colour and characteristics pleasant flavor.

Varieties

The varieties grown under different states are as below.

Bihar: Shahi, Rose Scented, China, Kasba, Purbi, Early Bedana, Late Bedana

Uttar Pradesh: Rose Scented, Dehradun, Calcuttia

West Bengal: Bombay Green, Kalyani Selection

Punjab: Muzaffarpur, Dehradun, Seedless, Late Bedana

In the recent years it has been increasingly realized that only increase in physical production of crops no longer guarantees the smooth development of agriculture at both the farm and the national economy levels unless and until it is linked with efficient system of marketing. As such, now a day in planning for agricultural development specially in developing economies marketing system had drawn much more attention than customarily assigned to it. Efficient marketing of agricultural commodities in general and fruits crops in particular plays an important role in safeguarding the interest of producer as well as consumer.

Litchi (Litchi chinensis Sonn.) a native of China, is grown in India since 18th century. It is member of the genus Litchi in the soapberry family, Sapindaceae. The name of the fruit is derived from the Chinese word lee chee which means “one who gives the pleasures of life”. Litchi is also known as the “fruit of romance” in China. The most important use of litchi is as table fruit in ripe form although it is also used in processed forms such as squash. The fresh fruit has a “delicate, whitish pulp” with a “perfume” flavour. Eating litchi can benefit those suffering from colds, fever and sore throats. Great source of Vitamin C and potassium, it also contains phosphorous, calcium, magnesium and protein. According to a Chinese book, the nature of the flesh of the litchi is warm and it can helps improveing the blood circulation. The Chinese also use litchi for medicinal purposes and for making wine. 

Genus : Litchi 
Species : chinensis  Sonn.
Family : Sapindaceae
(Sub family-Nepheleae)
Chromosome No. : 2n=30

A Chinese renowned statesman Chang Chow-ling of the eighth century in a poem on litchi indicated it as the most luscious of all fruits, and in quality surpasses the other two southern China’s famous fruits i.e. orange and peach. Litchi cultivation has been restricted to few selected sites mainly for its somewhat exacting in its climatic and cultural requirements. In recent times as litchi has established in the tropical America, there appears no doubt that very soon the fruits shall be in abundance in different parts of the tropics and subtropics. The most limiting factor in early dissemination of litchi was the perishable nature of seed and prior to steam navigation it was very difficult to transport the seeds from one continent to another successfully.

• Air layering is called “Marcottage” in China and “Gootee” in India.
• IBA (2-10g/liter of water) is most effective in root promotion in air layering of litchi.
• Flowers are petalless.
• Subtropical evergreen fruit tree; prefers a moist climate.
• Moist summer and cool winter favour litchi production.
• Red pigment – Anthocyanin.
• The pulp is an outgrowth of the seed in litchi.
• Roots – Mycorrhizal association (Fungus).
• July-October is the most appropriate time for propagation.
• January end to the onset of monsoon is a critical period for irrigation of litchi.

Litchi (Litchi chinensis Sonn.), a member of the Sapindaceae family, originated in China. An arillate fruit, it is widely cultivated in subtropical regions of the world, providing livelihood security to millions of people in south-east Asia (GalanSauco and Menini, 1989; Menzel and Waite, 2005). Litchi is important commercial fruit crop in India. It is popularly known as “queen” of fruits due to its attractive colour, taste, flavour and excellent quality. Nutritionally, it is rich in sugar content with appreciable content of protein, minerals, fibres, vitamins and calorific value. Litchi is consumed mainly as fresh and little as processed form. The juicy aril is an excellent thirst quencher. It is highly perishable in nature. The short span of fruit availability coupled with poor shelf-life, limits duration of its availability in the domestic as well as international market. Till date, it is meagrely exploited for potential production and due R & D support is still lacking.

PRESENT STATUS

At present annual fruit production is around 585,300 metric tonnes from an area of 84,170 ha and the national productivity is 6.95 tonnes/ha. In India, main production region is concentrated in Bihar, West Bengal, Uttar Pradesh, Uttarakhand, Assam, Jharkhand, Tripura, Punjab, Haryana and Himachal Pradesh. The area under this crop has undergone substantial expansion in the past 64 years with plantation increasing from 9,400 ha in 1949 to 78,000 ha, in 2013 (NHB, 2013). Till date, the present level of production is unable to cope up with the ever-increasing demand. Its fruits are available from early-May to July in different areas.

Litchi, Litchi chinensis, is one of the important fruit crops of South East Asia and Australian Continent. The crop thrives well in sub-tropical areas experiencing cool dry winters and warm wet summers. India and China are the major producers of litchi in the world. In India, Bihar, Uttarakhand and West Bengal contribute maximum in litchi production. Few major insect pests and mites are of concern, the details of which are as under:

Red rust, Eriophyid mite, Aceria litchii Keifer (Eriophyidae: Prostigmata) and red rust alga, Cephaleuros virescens Kunze (Trentepholiaceae: Trentepohliales)

Fruit borers : Criptophlebia illepida, Rapala varuna, Deudorix epijarbas, D. Isocrates : Lycaenidae

Of the four species, C.illepida is more damaging to litchi fruits. The larvae bore into developing fruits and seeds, filling the bore-holes with excreta and the infested fruits start rotting.

Origin and history- Litchi is a popular subtropical evergreen fruit; the white translucent flavoured aril is liked very much and is used for table purpose in India. The fruits are available during May–June in northern India. China is the biggest producer of litchi followed by India. In India major litchi producing areas are Mujaffarpur, Bihar mountain area of Saharanpur, Dehradoon, Hoshiyarpur and Gurdaspur district of Punjab.

Soil and climate - It can be grown sandy to clay loam and it prefer slightly acidic soil having pH range from 6-6.5 it has been reported that in acidic soil litchi root develop Micorrhyza. Which symbiosis of root fungus and there by Nitrogen fixation take place in atmosphere.

Litchi (Litchi chinensis Sonn.) is a subtropical and evergreen tree belonging to the family Sapindaceae. This fruit has highly specific climatic adaptability due to chilling requirement for floral initiation on one hand and the damage caused due to high summer temperature along with low relative humidity during fruit growth period on the other hand. Some other factors influencing expansion in different regions of the world are difficulties in establishment of plants in nursery and orchards, bearing and further into harvesting and post-harvest management. Calcium rich soil with mycorrhizae is best suited for the luxuriant growth of litchi plants which are commercially propagated by air-layering or gootee.

There has been a substantial increase in the area and production of litchi in India during the past 50 years. The area has increased from 9400 ha (1949–1950) to 91,000 ha (2016–2017). The contribution of litchi to the total area under fruit cultivation has increased from 0.75% to 1.70%. Increase in area during 1991–1992 to 2016–2017 (22 years) has been more than 80%, whereas production increase during the same period is to the tune of more than 150% (NHB, 2016–17). Productivity also recorded an increase of about 50% during the same period. Evidently, production and productivity of litchi are constantly increasing in the country. On a global scale, the fresh fruit market dominates the trade, followed by dried and canned fruit. Low success rate of establishment, lesser fruiting span, low and irregular yields because of poor flowering and fruit set, fruit cracking, browning and rotting of fruits, fruit borers and mites, poor shelf life, and lack of suitable varieties with early and late maturity and good-quality fruits are some of the factors encountered

A literature review attempts to discover, locate, and synthesize relevant research reports, articles, books, and other resources relating to a study subject. The review can be based on published sources like journal articles, conference papers, research abstracts, chapter books, research institution websites , and so on, as well as unpublished materials like theses and dissertations. By examining the literature, a researcher can take advantage of past research and results made by professionals to get the most out of their research.

Examining literature is an important part of every research project since it gives the investigator the information, they need to frame the study on the chosen topic. It directs an investigation on the appropriate path, keeping up with the most recent data.

Studies on Broad Areas of Webometrics

Webometric studies, ranging from earlier to more contemporary studies, have been recognized and organized under the following headings:

• Studies on the Growth and Development of Webometrics

• Studies on theoretical studies of content analysis

• Studies on Web Content Analysis

• Studies on web usage analysis

This chapter is an extensive survey of all past studies relevant to the field of investigation which gives knowledge of what others have found out in the related field of study. In any scientific investigation or research, a comprehensive presentation of the review of literature is a statutory requirement. Its main functions are to develop a better understanding of the problem to be investigated, delineate a new area of study and avoid unnecessary duplication, decide on the tools and techniques to be adopted including developing some new ones, also to relate the present study with the previous ones by finding out the areas of agreement and disagreement.

The review of literature of the present study is based on the major concepts related to the field of investigation. As direct references on the entire item are not in abundance, certain specific references along with some indirect references have been incorporated in this chapter for the purpose of meaningful use.

Review of literature helps a scholar describing and citing related works to justify the topic and objectives set in the thesis work. This is a splendid scholastic exercise to vindicate and validate the reasons and output of the research work undertaken.

Following is the classified review of literature for a systematic illustration and interpretation of the problem and axioms:

Source of risk

Boris and Radivoj (2017) reveal that agricultural risk and uncertainty come from many different places, but they can be categorized into five management-related categories: production and technology, prices and the market, finance, legislation, and employees.

Concept of Review of Literatures

The Review of literature is a systematic, explicit, and reproducible method for identifying, evaluating, and synthesizing the existing body of completed and recorded work produced by researchers, scholars, and practitioners. The Review of literature is also a resource paper, which includes the current knowledge including substantive findings, as well as theoretical and methodological contributions to a particular topic. These are available mostly in academic and scholastic journals.

Review of literature provides the basics for research in nearly every academic f ield. The aim of review of literature is to highlight what has been done so far in the field of interest and how our findings are related to earlier research. The review of literature also indicates the following by providing referential inputs.

(i) Approaches

(ii) Methods

(iii) Variables used

(iv) Statistical procedure

(v) Expected results

Concept of Review of Literatures

The Review of literature is a systematic, explicit, and reproducible method for identifying, evaluating, and synthesizing the existing body of completed and recorded work produced by researchers, scholars, and practitioners. The Review of literature is also a resource paper, which includes the current knowledge including substantive findings, as well as theoretical and methodological contributions to a particular topic. These are available mostly in academic and scholastic journals.

Review of literature provide the basics for research in nearly every academic f ield. The aim of review of literature is to highlight what has been done so far in the field of interest and how our findings are related to earlier research. The review of literature also indicates the following by providing referential inputs.

(i) Approaches

(ii) Methods

(iii) Variables used

(iv) Statistical procedure

(v) Expected results

(vi) Provides theoretical background to our study.

(vii) Helps justify how our findings are related to our body of knowledge in our field of research.

(viii) Establishes a link between what we propose to study and what has already been found. It helps us to refine our research methodology.

Review of literature enables a researcher summarizing and quoting relevant works to explain the topic and objectives stated in the thesis study. This is a fantastic scholastic activity to justify and validate the reasoning and outcome of the research study conducted.
Following is the categorized review of literature for a systematic illustration and interpretation of the issue and axioms:
Source of risk
Boris and Radivoj (2017) classified agricultural risk and uncertainty into five primary management-related categories: production and technology, pricing and the market, money, law, and personnel. Production and technology risks encompass challenges such as crop diseases, pests, and technological failures that can adversely affect yields. Managing these risks involves implementing advanced farming techniques, investing in new technologies, and employing effective pest and disease control measures. Pricing and market risks include price volatility and issues related to market access and consumer preferences. Strategies to mitigate these risks include using futures contracts, diversifying markets, and conducting thorough market analysis. Money risks pertain to financial management, including fluctuating interest rates, capital investment needs, and cash flow challenges. Effective management here involves maintaining a robust financial plan, leveraging insurance, and building financial reserves. Law risks relate to compliance with regulations on land use, environmental standards, and food safety. Addressing these involves staying up-to-date with legal requirements and seeking legal counsel when necessary. Personnel risks involve labour shortages, skill gaps, and workforce management issues. These can be managed through investments in training, fostering a positive work environment, and implementing effective recruitment and retention strategies. Addressing these five areas comprehensively helps agricultural operations reduce the likelihood and impact of adverse events, enhancing resilience and sustaining productivity and profitability amidst uncertainty.

Ambasankar, K. and Balakrishnan, V. 2011. Influence of protected sardine oil on in vitro rumen fermentation and nutrient digestibility of complete diet. Indian J.  Anim. Sci., 81(1): 
84-86.
Amrutkar, S.A., Thakur, S.S. and Pawar, S.P. 2014. Economics of supplementing rumen protected methionine and lysine in the ration of lactating crossbred cows. Indian J. Anim. Nutr., 31 (1) : 14-19.
AOAC, 2005. Association of Official Analytical Chemists. Official Methods of Analysis. Washington, DC.
Arewad, G. R., Thube, H. A., Pandya, P. R., Parnerkar S. and Shankhpal S. 2011. Effect of feeding bypass protein based total mixed ration on performance of growing crossbred calves. Indian J. Anim. Nutr. 2011.28 (3) : 303-308.

Accorinti, J.1983. Antifungal products from algal origin. Rev Int Ocean Med, 72, 45-53.
Allnutt, F.C.T. 1996. Cyanobacteria (Blue -Green Algae) Biotechnology: Past, Present and Future. Journal of Scientific and Industrial Research. 55, 693-714.
Ananthanarayan, R. and Paniker, C.K.J. 2005. Textbook of Microbiology (VII Ed.) Orient Longman Pvt Ltd, Chennai-600 002. pp 1-657.
Asthana, R.K., Srivastava, A., Singh, A.P., Deepali, Singh, S.P., Nath, G., Srivastava, R. and Srivastava, B.S. 2006. Identification of an antimicrobial entity from the cyanobacterium Fischerella sp. isolated from bark of Azadirachta indica (Neem) tree. Journal of Applied Phycology. 18, Number-1, 33-39.
Ayehunie, S., Belay, A., Baba, T.W., and Ruprecht, R.M. 1998. Inhibition of HIV-1 replication by an aqueous extract of Spirulina platensis (Arthrospira platensis). J. Acquir. Immune. Defic. Syndr. Hum. Retrovirol. 18, 7-12.

A thorough review of existing literature forms the cornerstone of any specific investigation. Research does not occur in isolation; rather, it is built upon the accumulated knowledge, insights and relevant findings of the earlier studies. As the part continues to shape the trajectory of future enquiry, examining prior research provides valuable guidance, conceptual clarity and a framework within which the present study can be situated. Recognizing this, efforts were made to systematically collect and review scholarly contributions that bear relevance to the present investigation. Although contract farming has emerged as an increasingly important institutional arrangement in Indian agriculture, the body of literature availableparticularly in the discipline of Agricultural Extension-remains comparatively limited. Much of the research attention has traditionally been directed toward areas such as the adoption of agricultural technologies, while the broader socio-economic and behavioural dimensions of contract farming have received relatively less systematic analysis. This creates a noticeable gap that the present study seeks to address.
Despite these limitations, the available research offers meaningful insights into how contract farming shapes rural livelihoods. Studies point to the potential for income enhancement, employment generation and poverty reduction, while also highlighting diverse socio-personal and psychological attributes of farmers that influence the participation and outcomes. Moreover, research also identifies several constraints-ranging from institutional and infrastructural barriers to communication gaps, that potentially affect the effectiveness of such arrangements.
For the sake of clarity and coherence. The literature reviewed has been organised under the following thematic headings:
I. Contract farming and poverty reduction in terms of income generation- studies that explore how the participation in contractual arrangements with agribusiness firms contributes to farmers’ earnings, household income security and poverty alleviation.