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Ribbed gourd (Luffa acutangula (L) Roxb.) belonging to the family Cucurbitaceae is a well known vegetable variety in India. The seed production can be done in both summer and rainy season.
Method of seed production

Bitter gourd is a cross-pollinated crop which occurs through bees. Seeds should be allowed to set by open-pollination in isolation. The isolation distance maintained between the fields of other varieties and the fields of the same variety not conforming to the varietal purity requirements for certification is 1000 metres for foundation and 500 metres for certified seed production.

I. FILL UPS

1. The stigma receptivity of ribbedgourd is_____.
2. Ribbedgourd is a _____ pollinated crop.
   1. Isolation distance for foundation seed production of ribbedgourd is _____.

The field is ploughed once and harrowed twice or thrice until the soil becomes well puddle. Beds are made slightly raised of 1 – 1.5 m in width and conveniently large in size and drainage channels in between the beds. The total area of nursery required to plant one hectare of land is 20 cents (800 m2 ). This method is suited where assured irrigation facilities are available. The beds should not be allowed to dry because they develop cracks and the seedlings will get spoiled. This method keeps down the weeds in the nursery. Seedlings are transplanted at 21-25 and 25-30 days age for SDV and MDV, respectively. Sparse sowing is recommended in case of hybrid rice. One kg of hybrid seed is sown in one cent area of nursery. This helps in good tillering and robust seedlings and makes it possible to transplant single seedling per hill. Seedlings are planted at 20-25 days.

3.1. Introduction

Rice is grown in varying geographical locations and climatic situations. Most of the rice area lies between the equator and 400 N latitude and between 700 and 1400 E longitude. It grows well from tropical to sub-tropical warm and temperate climatic regions up to 400 S and 500 N of the equator. However, the highest yields are obtained in the region between 300 and 450 N of the equator. The average yield generally increases as the countries are situated further away from the equator (Chatterjee and Maiti, 1985). In India, rice grows in regions from 80 N to 350 N latitudes under widely varying conditions of the land, rainfall, altitude and climatic conditions. It is grown at the sea level in river deltas as in parts of Kerala, as deepwater in states of West Bengal, Assam and Bihar; at high altitudes of 914 to 1524 m or even more as in Kashmir, and in the slopes of the Himalayas. A temperature range of 200 C to 37.70 C is required throughout the life period of rice crop.

1. Introduction

Celiac disease (CD) is an immune-mediated enteropathy triggered by the ingestion of gluten in genetically susceptible individuals. Gluten is the protein component in wheat, rye and barley. In the last 10 years, cutting edge scientific developments in this disease have led to the formulation of new concepts of epidemiology, pathophysiology and clinical manifestations. At present, the only available treatment for CD is a strict gluten-free diet (GFD) (Mulder et al., 2013; Theethira and Kelly, 2014). Until recently, the geographical distribution of CD was mostly restricted to Europe and other developed countries, such as the United States, Canada and Australia. Celiac disease is not only frequent in developed countries, but it is increasingly found in areas of the developing world, such as North Africa (Malekzadeh et al., 2005), Middle East (Rostami et al., 2004) and India (Basu et al., 2014, Deora et al., 2014; Yachha and Poddar, 2007). New epidemiological studies have brought evidence that this disorder is common in many developing countries as well, showing that the ‘global village of celiac disease’ has indeed a worldwide distribution (Fasano and Catassi, 2001).

The only available treatment for celiac disease is the strict, lifelong avoidance of gluten. When gluten is removed from the diet, the small intestine will start to heal and overall health should improve (Fasano and Catassi, 2001). Traditional substitutes for gluten-containing grains have been rice, tapioca, corn, and potato. However, more nutrient-dense grains, seeds, nut flours, and legumes are being incorporated into the diet to provide an enhanced palatability, variety, and nutritional quality. These include sorghum, millet, teff, quinoa, amaranth, flax seed, and buckwheat.

1. Blast
Diagnostic Symptoms
• Pathogen attacks the crop at all stages of crop growth.
• Symptoms appear on leaves, nodes, rachis, and glumes. On the leaves, the lesions appear as small bluish green flecks, which enlarge under moist weather to form the characteristic spindle shaped spots with grey centre and dark brown margin (Leaf blast).
• Spots coalesce as the disease progresses and large areas of the leaves dry up and wither. Severely infected nursery and field appear as burnt.• Black lesions appear on nodes girdling them. The affected nodes may break up and all the plant parts above the infected nodes may die (nodal blast).
• During flower emergence, the fungus attacks the peduncle and the lesion turns to brownish-black which is referred to as rotten neck / neck rot / panicle blast (neck blast).
• In early neck infection, grain filling does not occur while in late infection, partial grainfilling occurs (Fig.1).

Introduction

Rice (Oryza sativa L.) is a staple food of over half the world’s people and is grown on approximately 146 million hectares, more than 10 per cent of total available land. Ninety seven per cent of the world’s rice is grown by less developed countries, mostly in Asia. Post harvest losses are considered to be contributed by storage alone, and not much attention was paid to losses occurring during harvesting, transport, threshing, drying, milling and pre-milling treatments. Quantitative loss of food grains was the main concern of the producers and the consumers. Qualitative losses at various stages were not fully recognized, but systematic studies by different organizations revealed that these losses are enormous and should be prevented. These losses cumulatively could be as high as 40 per cent and are normally accompanied by loss of quality also. Quality loss of products can take place at all stages but more particularly during drying or curing of harvested crops, storage, and milling and pre-milling treatments. Post-harvest attention is essential if the grains of higher production are to be fully exploited. Also the quality loss occurring in food grains can be extremely serious if the farming community is not aware of them.

I. FILL UPS

1. The inflorescence of rice is _____.
2. The rice flower is called _____.
3. The stigma receptivity of rice crop is_____ period.
4. The pollen viability of rice is for _____.
5. The grain stem of rice is called_____.
6. Rice is _____ pollinated crop.

Cereal grain contains 60 to 70% of starch and is excellent energy rich foods for humans. In almost every country and region, cereals provide the staple food. In the world as a whole, only 5% of starchy staple food comes from root crops (mainly cassava, potato, and yams, depending on climate), whereas the rest is from cereal. Cereals are an excellent source of fat-soluble vitamin E, which is an essential antioxidant. Whole cereal grains contain 20 to 30% of the daily requirements of the minerals such as selenium, calcium, zinc and copper.

1.1. Introduction: India’s present population, growth rate & projections

India is the second-most populous country in the world after China with its population of about 1.38 billion in the year 2020. The Population Division under the Department of Economic and Social Affairs, of the United Nations, has projected the country’s population to be growing to about 1.50 billion by the year 2030, and 1.64 billion by 2050, of course with its decreasing annual growth rate from 1.04 to 0.25% or so during the period of next thirty years (Fig. 1.1; UNDESA, 2019). The projection says the Indian population will exceed China by the year 2030 even with its decreasing rate i.e. India will be the most populous country by then. As agriculture and allied sectors are the backbone of this country and the largest livelihood source, it support this growing human and livestock population with diversified natural resources and varied agro-climatic conditions. However, the sustainability of agricultural production should be maintained in the face of perturbation and stress on the agro-ecosystem especially the degraded natural resource base and changing climate.

Rice (Oryza sativa L., 2n = 2x = 24, monocot, family Poaceae formerly called as Gramineae, grass family, self-pollinated crop) is one of the Four Big Crops (rice, wheat, corn and soybean) globally and is the world’s most important food crop after wheat and corn. In crop year 2018, there was around 167 million hectares of paddy (rough, un-milled rice) cultivated area worldwide with production of 782 million tons resulting into a productivity of 4.68 tons/ha. The top ten countries in rice production during this period globally were China, India, Indonesia, Bangladesh, Vietnam, Thailand, Myanmar, Philippines, Brazil and Pakistan. Chinese production was 212 million tones followed by India with 172 million tons (FAOSTAT). Indian production of 172 million tons of rough rice can be converted into milled rice by multiplying a conversion factor of 0.67 and this way it comes to 115 million tons.

Introduction

Rickettsial diseases in poultry are caused by various species of bacteria belonging to the genus Rickettsia. These diseases can have significant economic implications for the poultry industry due to decreased production, increased mortality, and trade restrictions. Rickettsial diseases affecting poultry are relatively uncommon compared to other pathogens but can still occur. Rickettsial organisms are tiny, pleomorphic, weakly gram-negative bacilli that multiply by binary fission. The Rickettsia requires an arthropod for transmission and to complete its life cycle. The organisms are non-motile and non-capsulated and possess both DNA and RNA. Some of the rickettsial diseases affecting poultry include:

1. Rocky Mountain spotted fever: Chickens can be infected with various species of Rickettsia, including Rickettsia rickettsia, which causes Rocky Mountain spotted fever in humans. In chickens, rickettsial infections can lead to symptoms such as fever, lethargy, decreased egg production, respiratory distress, and neurological signs.

History of Rickettsial infections went back to 16^th century and it has long been associated with famine and war. Thus Rickettsial infections played a significant role in the history of Western civilization. Epidemic typhus had major impact to decide over the outcome of several wars. This epidemic alone killed or caused great suffering to over 100,000 people in the two World Wars.  However, the causative agent was not determined until the early part of the 20^th century. Rocky Mountain Spotted Fever (RMSF) was the first detected Rickettsial infection as early as in 1896 in Idaho Valley, USA.  It was originally known as ‘Black Measles’ because of its clinical appearance in the form of characteristic spotted rash appearance throughout the body of the patients. Howard Taylor Ricketts, an American pathologist for the first time described the causative agent of Rocky Mountain spotted fever and was able to isolate it in the laboratory animals during 1902-1909. He was a dedicated scientist and, on several occasions, injected himself with a pathogen for experiment. The causative pathogen of Rocky Mountain spotted fever, Rickettsia rickettsii was named after him. Later, the family Rickettsiaceae as well as the order Rickettsiales was named after him. Ernest William Goodpasture, an American pathologist and physician, invented the methods of isolation and culturing the rickettsial pathogens in chicken embryos and fertilized chicken eggs.

The reclassification of the order Rickettsiales was predicated upon comprehensive genetic analyses of 16S rRNA, groESL, and surface protein genes. Consequently, organisms within this order were systematically assigned to one of two families: Anaplasmataceae and Rickettsiaceae. Within the Anaplasmataceae family, phylogenetic analyses consistently delineated four genetically distinct clades: (1) Anaplasma, (2) Ehrlichia, (3) Wolbachia, and (4) Neorickettsia. Despite the obligate intracellular nature of rickettsial organisms in both families, those classified under Rickettsiaceae proliferate freely within
the host cell cytoplasm, whereas members of the Anaplasmataceae family are confined exclusively to membrane-bound vacuoles within the cytoplasm of host cells.
The first documented cases of anaplasmosis trace back to the late 19th century in South Africa. However, it wasn’t until 1910 that the causative agent of the disease was conclusively identified morphologically as “marginal points” within red blood cells by Max Theiler, later named it Anaplasma marginale. A year later, he identified another species, A. centrale, which caused a milder form of the disease in cattle. During the 1930s, Sanborn, Stiles, and Moc demonstrated the mechanical transmission of A. marginale by horse flies and stable flies. In the late 1980s, the life cycle of A. marginale was fully elucidated in ticks belonging to the genus Dermacentor.

Organisms in the order Rickettsiales form a diverse group of small (0.3 to 0.5 x 0.8 to 2.0 pm), non-motile, pleomorphic Gram-negative bacteria which replicate only in host cells. They can be cultured in the yolk sac of embryonated eggs or in selected tissue culture cell lines. Because they stain poorly with aniline dyes, these organisms should be stained by Romanowsky methods such as Giemsa or Leishman. In addition to host-cell dependence and poor affinity for basic dyes, a requirement for an invertebrate vector distinguishes them from conventional bacteria and the Chlamydiales.
Epidemiology
Animal hosts and arthropod vectors are the reservoirs for most rickettsiae. A number of rickettsia1 organisms, including Ehrlichia canis, Anaplasma marginale and Haemobartonella felis produce latent infections. In arthropods, rickettsiae replicate in the epithelial cells of the gut before spreading to other organs, including the salivary glands and ovaries where further replication may occur.
Organisms are transmitted when the arthropod feeds on the animal host. Some organisms such as Rickettsia rickettsii are maintained in a tick population by transovarial transmission. Trans-stadial but not transovarial transmission of E. canis and E. phagocytophila occurs in ticks. With the exception of Coxiella burnetii, which produces endospore-like forms and can remain viable in dust for up to 50 days, most rickettsiae are labile outside host cells. Aerosol transmission of C.burnetii commonly occurs in domestic animals and humans. In addition, a silent cycle involving ticks and small wild mammals may constitute a possible source of infection for some domestic species.
Pathogenesis and Pathogenicity
Many Rickettsia species including the causal agents of typhus (R. prowuzekii), murine typhus (R. typhi) and scrub typhus (R. tsutsugamushi) are primarily human pathogens. Rocky Mountain spotted fever, caused by Rickettsia rickettsii, which is a common rickettsia1 disease of humans, also affects dogs.

Ridge gourd or Ribbed gourd (Luffa acutangula Rox b. L) and Sponge gourd or Smooth gourd (Luffa cylindrica) have diploid chromosome number  2n=2x=26. Luffa has old world origin in Subtropical Asian region including India (Kalloo, 1993). These two species are inter-crossable. F1 plants generally, intermediate between the parents and showed various irregularities like, univalants, rings and chains of 4 chromosomes, chromatids bridges and fragments at metaphase and thus the species are not easily crossable and the F1 plants appear to be of not much practical value. The genus is monoecious annual vine, tendrils are branched, flowers are yellow, anthers are free and pistil has three placentas with many ovules and stigma are three and bilobate. Fruits oblong or cylindrical and rind becomes dry on maturity.

Ridge gourd, Luffa acutangula and sponge gourd, Luffa cylindrica under the family Cucurbitaceae (Chromosome number: 2n = 2× = 26) is an important warm season fruit vegetable crop. Ridge gourd is widely cultivated in India, Southeast Asia, China, Japan, Egypt and other parts of Africa. Sponge gourd is now cultivated in all tropical regions of the world. It was an important crop used for industrial filters until World War II and Japan cultivated the best crop for this purpose. The main commercial production areas of sponge gourd today are China, Korea, India, Japan, Central America and Brazil. Immature fruits of ridge gourd and sponge gourd are eaten as a vegetable and at maturity both become very fibrous. The word luffa or ‘loofah’ is of Arabic origin and the sponge characteristic of the crop has been described in old Egyptian writings.
Fruits are good sources of vitamin C, riboflavin, zinc and antioxidants. It is effective in balancing blood sugar levels, help eliminate toxic waste and prevent fat accumulation. Ridge gourd also helps reduce excessive body heat during summers which can prevent many ailments.
 

Ridge gourd also known as ribbed gourd or angled gourd or silky gourd or angled loofah or vegetable gourd (Luffa acutangula (Roxb. L., 2n = 2x, family Cucurbitaceae, mostly monoecious and cross-pollinated but behaving like self-pollinated crop in term of no inbreeding depression) is not a crop of global importance; rather it is grown and consumed primarily in India and the adjoining countries which used to be part of greater India. In India, estimated area is 50,000 ha spread over almost entire country but the leading states are UP, Bihar, West Bengal, MP, Chhattisgarh, and Maharashtra, Karnataka, Tamil Nadu and north east hill region.

Origin and Domestication

Ridge gourd has similar origin as that of sponge gourd (refer to page 428).

Ridge or ribbed gourd (Luffa acutangula (Roxb.)L.) is grown commercially and in homesteads for its immature fruits which are used as cooked vegetable. It is a popular vegetable both as spring-summer and rainy season crops. It is grown in tropical and subtropical countries, especially in Asia and India as an important cucurbitaceous vegetable crop (Jansen et al., 1993). The immature fruit is a rich source of dietary fiber and minerals (Sheshadri, 1990). Apart from culinary properties, it has vast medicinal properties which are traditionally used for the curing of stomach ailments and fever (Burkill, 1985; Chakravarty, 1990). The genus derives its name from the byproduct 'loofah', which is used in bathing sponges, doormats, scrubber pads, mattresses, pillows and in cleaning utensils. The tender fruits are prescribed for people suffering from malaria and other seasonal fevers because it is easy to digest and act as an appetizer. Ridge gourd contains 0.5g protein, 3.4g carbohydrates, 37mg carotene and 18mg vitamin C per 100g of edible portion. Some round varieties of ridge gourd are also used for stuffing purposes.

Ridge gourd is originated from India and is grown throughout the country by many of the small and marginal farmers for their regular income. Uttar Pradesh, Madhya Pradesh, Punjab, Chhattisgarh, Bihar, West Bengal, Maharashtra and all southern states like Andhra Pradesh, Telangana, Karnataka, Kerala and Tamil Nadu are the major states in India where ridge gourd is cultivated. It is grown in an area of 1.00 lakh ha in India with a productivity of about 10 12 t/ha which is very low.