Lotus Literature Review

TABLE OF CONTENTS
Introduction
Natural History
Origin and Geographical Distribution of Lotus
Biology of the Species
Cultural Influence
Plant Uses
Medicinal and Nutritional Values
Cultivation
Sexual and Asexual Propagation
Soil Conditions
Fertilization
Container Management
Pond Management
Vegetable Production
Field Production
Planting and Harvest
Packaging and Post-harvest Handling
Markets
Conclusions
References
Tables
Return to AU Lotus Project Page

INTRODUCTION
The Black Belt region lies within the south’s Gulf Coastal Plain. It stretches from eastern, south-central Alabama into northwestern Mississippi. In the 1820s and 30s, the Black Belt was identified as a rich, dark, cotton-growing area. The agricultural potential of the area drew hundreds of immigrants primarily from Georgia and the Carolinas. This migration, and the subsequent forced removal of Native Americans, allowed the Black Belt to emerge as the core of a rapidly expanding plantation area. During that period, half of Alabama’s enslaved population was concentrated within ten Black Belt counties and the exploitation of their labor made this one of the richest regions in the antebellum United States. However, in the first-half of the twentieth century, years of soil erosion caused by the boll weevil (Anthonomus grandis) invasion, the collapse of cotton tenancy, the failure to diversify economically, and the urban exodus combined to mire the southern Black Belt in a seemingly irreversible decline. As a consequence, what had once been one of America’s richest and most politically powerful regions became one of the poorest (Tullos, 2004).

Today’s Black Belt region is known as a crescent-shaped region extending from Texas through Alabama to Virginia and is characterized by the dark color of the soil. The region is also known for its economic poverty (Tian et al, 2006b). This region presents numerous challenges to economic development efforts, especially in the arena of production of crops and other types of farming. However, due to the environmental conditions, there is a fairly well-developed aquaculture industry in the area with 10,000 water hectares of fish farmers in the state owned by 250 large-scale producers. The state raises 20 aquatic species and in 2005 it produced over 71,000 t of catfish (Crews and Chappell, 2006). Despite the current production, the state has the land and water resources to support an industry 10 times its current size. Incorporating small farmers can help with such an expansion, but in order to promote sustainability and make the enterprise more lucrative, double-cropping (fish/vegetables) should be implemented.

Lotus (Nelumbo nucifera) is a perennial water plant grown as an ornamental which produces roots that are very popular as a vegetable. In addition, leaves, stems, seeds and other parts are edible and many organs of the plant are thought to have multiple medicinal properties (Ono et al, 2006). As a vegetable and medicinal herb, Lotus can be grown in situations not favored by other crops. In the southeast, the environmental conditions to grow Lotus are the same as those to produce fish in ponds. Produced in association with catfish, Lotus requires little care and there are hundreds of ornamental cultivars with different sizes, flower forms and colors. Lotus production in association with aquaculture farms has the potential to increase the economic revenue from already established infrastructures (fish ponds); diversify farm production; explore the feasibility of growing other aquatic crops in the Black Belt region; make fish farm operations more economically sustainable.

In order to develop Lotus as an alternative vegetable and ornamental crop it is important to understand the basic biology and physiology of the crop. A deeper background of the plant (history, potential uses, nutritional and medicinal values) might allow for future development for a marketing strategy. Furthermore, agronomic practices should be reviewed to determine their economic potential. The objective of this study is to review the literature related to the crop, summarize some of the most relevant aspects, and provide a good source of references for further investigation.

NATURAL HISTORY
Origin and Geographical Distribution of Lotus

Lotus belongs to the Nymphaeaceae family and the genus Nelumbo. There are only 2 species in this genus: Nelumbo nucifera Gaertn distributed in Asia and Oceania, and Nelumbo lutea distributed in North and South America (Qichao & Xingyan, 2005). Although, the species nucifera is the most important (commercially and culturally), it is critical to describe the American species, evaluate its horticultural value, and its potential as a source of genetic diversity.

The American species, represented by Nelumbo lutea (Syn. Nelumbopentapetala or Nelumbium luteum) is known as American Lotus, Water-chinquapin, and Yellow Lotus (Sayre, 2004) and is native to the eastern and central portions of the US ranging from Maine to Wisconsin and in the south from Florida to Texas. It is also possible to find native stands throughout Central America and northern South America. Small native populations can still be found in the West Indian Archipelago and the extreme southeastern portion of Ontario, Canada. In some areas the natural environment for Lotus is being destroyed and the plant populations have dramatically decreased. The plant is listed as endangered in New Jersey and Pennsylvania and threatened in Michigan and Delaware (Sayre, 2004).

The name “Lotus” can be confusing since several plants have been known by this name. Nelumbo nucifera (Syn. Nelumbium speciosum Willd) is known as: Sacred Lotus, Indian Lotus, or Asian Lotus. Other names includes: Lotus root (rhizome), East Indian Lotus, Egyptian Lotus, Lian, Lin ngau-China, Hasu - Japanese name for the plant, Renkon-edible storage rhizome in Japanese (Yamaguchi, 1990). The name Sacred Lotus of India is an appellation also applied by Egyptians to some species of water lilies. For instance, Nymphaea caerulea it is known as the Blue Lotus of the Nile (Slocum and Robinson, 1996). There have been suggestions that Lotus may have originated in India. However, Hsu Jin, a noted paleontologist failed to find any petrified Lotus seeds in India. The suggestion that Nelumbo might have originated in India came from J. Gaertner, a European botanist, who described the plant morphologically and named it. The name Nelumbo is the name of a place located in Sri Lanka, south of India, which might account for the idea that this plant originated there, consequently the common name “Indian Lotus” emerged (Qichao & Xingyan, 2005). Japanese scientists consider the origin of Lotus to be China (Xueming, 1987). Qichao & Xingyan (2005) consider China as Lotus’ main distribution and cultivation center. In accordance with their research, this plant has been known for more than 6000 years and has been artificially cultivated for more than 3000 years. They also reported that petrified Lotus seeds have been found in various areas of China during recent oil explorations. According to recent archeological studies and C14 analysis, the Chinese history has been related to Lotus for at least 7,000 years (Xueming, 1987). Xueming also mentioned that Lotus had grown along the Yangtze River and Yellow River area before that time. This has been substantiated by the fact that many Lotus seeds were found that had been buried for nearly 1,000 years.

The origin of the Sacred Lotus is still debated. Originated in Asia and its wild distribution is understood to have been from the Caspian Sea in the west to Japan in the east and from the Soviet Union in the north to the northern part of Australia (Xueming, 1987). It can be found in Iran, India, Vietnam, Korea, Japan, Malaysia, New Guinea, China and Australia.

Biology of the Species
Nelumbo lutea Willd is a long-lived aquatic perennial with cylindrical, spongy rhizomes that produce thick tubers in the fall. Some populations are found in headwater lakes of riparian corridors. The plant prefers water depths from 2 to 7 ft. Most plants establish themselves in shallower water and subsequently grow out to deeper water. N. lutea blooms from June to September and the cream to yellow colored flowers open on a single stalk and range from 3 to 8 inches in diameter when fully open. A single bloom lasts from 3 to 4 days.

According to Sayre (2004), if a flower was successfully pollinated, most holes will contain a single round, developing seed. The seeds are actually located in the woody receptacle that looks like a showerhead. The hard, brown seeds, about 1 cm (0.4 inches) in diameter, will survive for long periods of time. The leaves are orbicular in shape with crenulate margins. They range from 1 to 2 ft. in diameter with the petiole attached to the leaf at the center. The peltate, palmate leaves are slightly concave, giving the impression of a shallow bowl. Leaves arise directly from the rhizome and can either be floating on the water or raise 1 to 1.5 feet above the water (Sayre, 2004).

Nelumbo nucifera Gaernt is a perennial water plant that is being grown in Asian countries both as an ornamental and for its edible rhizomes and seeds. Rhizomes are thick and tuberous and grow at the bottom of ponds or slow-moving streams (Magness et al. 1971). The leaves are nearly round and large in diameter. The stems are long and thorny. They float in deep water especially when young. In shallow waters, depending on the cultivars, the leaves rise high. The plant completes a cycle in less than a year. Usually, the plant will take 4-6 months to bud, leaf out, flower, fruit, form a rhizome, mature and reach a dormant period (Xueming, 1987).

Most of the varieties found in lutea and its crosses with nucifera are only used as ornamentals.


Flowering ornamental Lotus (Nelumbo nucifera).

The limited reports on its uses for food/medicine do not specify particular varieties/cultivars and therefore it is assumed that those references refer to the species only. On the other hand, the different varieties and cultivars of Asian Lotus have been classified in different ways based on: use, flower-type, form, and size. Lotus cultivars have been classified into three classes: seeds, flowering and rhizome (Qichao & Xingyan, 2005; Nguyen, 2001b). There are varieties that show one or more characteristics, however, they are classified according to their strongest feature (Nguyen, 2001a). There is a wide genotypic variation related with starch content and growing water levels. Often, varieties that are used for the production of rhizomes produce few flowers. On the other hand, the varieties that are used to produce seeds have no appreciable rhizome (Nguyen and Hicks, 2004). Researchers at Auburn University categorized the cultivars according to size: large (6-8’), medium (3-4’) and dwarf types (1-2’) (Tilt, 2006. Personal communication). In China, cultivars are classified based on 4 characteristics: plant height, flower diameter, flower form [single petal, semi-double flowers, and double], and flower color. The considerable variation in flower color and shape has made Lotus one of the most popular ornamental and cultivated plants in Asia (Masuda et al, 2006). In China, for example, there are between 400-600 cultivars (Qichao & Xingyan, 2005); India has more than 160 cultivars (BGCI, 2006). Several countries have breeding programs aimed at developing cultivars with better rhizomes and/or greater seed producers. The Chinese cultivar ‘Oulian’, has been specifically developed for producing high quality rhizomes with few flowers or seeds. ‘Zilian’ is another Chinese cultivar grown for seed production (Follett and Douglas, 2003). In Australia, the Germplasm inventory for UWSH and Gosford HRAS reported the following cultivars as rhizome producers: ‘Paradise’, ‘Quangdong’, ‘Green Jade’, ‘Damaojie’, ‘Zhouou’, ‘Paozi’, ‘Big Lying Dragon’, and ‘Bitchu’. The Auburn Germplasm collection has more than 130 ornamental cultivars. Most of the edible cultivars are Chinese: ‘Space 36’, ‘E#2’, ‘04-R-31’, ‘04-R-07’, ‘Hunan’, ‘White Stamen Hunan’, ‘Red Flower Fujian’, ‘White Hunan’, ‘Hubei # 5’, ‘White Flower Fujian’, ‘Wuzhi # 2’, ‘Hainan’, ‘Big Lying Dragon’, and ‘Jianzuihonghua’.

Cultural Influence
American Indian tribes treated their native Lotus as a sacred plant with mystical powers and the Comanche, Dakota, Huron, Meskwaki, Ojibwa, Omaha, and Potawatomi used various parts of the Lotus plant as a source of supplemental food. In China, the Asian Lotus and its flowers have been appreciated by all kinds of people. Artists have painted Lotus; poets and scholars have written poems and essays about the plant. The Chinese have developed a romance with Lotus flowers (Xueming, 1987). The ancient people of Tibet and Nepal held Lotus in veneration. An ancient prayer heard in Tibet and other Himalayan regions included the phrase “Om mani padme hum,” which can be translated as “Oh, the jewel in the heart of the Lotus” (Slocum and Robinson, 1996). Hindus believe that Buddha was born in the Lotus heart. From Indian culture came the Brahmin claim that from a Nelumbo mystic blossom sprang the absolute creator of the universe – Bahma. In Japan, Lotus is considered the symbol of life because of its edible parts. In Japanese legends and religious developments of the past, the plant represented sincerity and nobility due in part to its annual emergence from the still waters (Slocum and Robinson, 1996).

Plant Uses
Several organs of Nelumbo lutea are edible. Leaves and young stems are eaten cooked. The large tuberous roots (the size of a human arm) used to be baked like sweet potatoes while the leaves were eaten like spinach. The root is rich in starch and when baked (after having been steeped in water to remove any bitterness) it becomes sweet and mealy, somewhat like a sweet potato.


Rhizomes sliced and ready to eat.

The hard seeds were gathered and eaten like nuts, added as a thickening to soups, or roasted like chestnuts (Sayre, 2004). Further, they can be dried and ground into flour for making bread. The seed contains up to 19% protein and edible oil can be extracted from it. Finally, the flowers are fragrant and the pods are quite striking and often used in flower arrangements.

Nelumbo nucifera is cultivated for its edible rhizomes in China, Japan, Hawaii, India, and Korea (Hanelt, 2001). In Mexico (Rogers and Redding, 2003) and Australia (Nguyen, 2001a), the crop is considered or grown as a non-traditional vegetable for the export market.


Edible rhizome from a Chinese cultivar 'Hubei #5'.


Shipment propagation material for 'Hubei #5'.

Different edible cultivars show compositional variation. Xueming (1987) evaluated 33 varieties and reported the following constituents: 8.4-22.7% starch, 1.4-4.8% total sugars, 0.2- 2.34% reducing sugars, 1.9-2.44% protein, 0.7-1.0% free amino acids, 25.9-35.0 mg Vitamin C, 0.13-0.19 mg Vitamin B6/100 grams of tissue. For seeds, he reported: 38.3-57.8% starch, 8.55-19.1% total sugars, 0.8-6.3% reducing sugars, 1.5-2.4% lipids and 17.1-25.4% protein.

The starchy rhizomes are eaten roasted, as pickles and as dried slices, fried as chips or used for starch production. The acorn-like seeds are also an oriental delicacy. These are eaten raw, roasted, boiled, pickled, candied or ground as meal. The young leaves, leaf stalks and flowers are consumed as vegetables.


Torus or fruit of lotus.


Ripe seeds.


Fresh seeds can be eaten raw after the removal of the bitter embryo.


In China seeds are roasted and sold like peanuts.

The rhizomes, leaves and flowers are used in savory dishes (Kew, 2006). Flowers are used for the production of perfume (Hanelt, 2001). The fruit is an enlarged receptacle containing many embedded seeds (Magness et al., 1971). Immature seed pods and leaves are used in culinary preparation. All parts of the Lotus plant, in one form or another are used in Chinese medicine (Xueming, 1987). In India, honey made by bees visiting Lotus flowers is considered a tonic known as ‘Padmammadjhu’ or ‘Makaranda’ and it is used to treat eye disorders (Kew, 2006).

Medicinal and Nutritional Values
Nelumbo nucifera is considered an important traditional Chinese herb and all parts of it are used in medicine. The rhizome extract showed anti-diabetic (Mukherjee et al, 1997) and anti-obesity attributes (Ono et al, 2006). The leaves are known for their refrigerant, astringent and diuretic actions. This led to diverse applications such as using the leaves for diarrhea, high fever, hemorrhoids and leprosy (Ku-Lee et al, 2005; Nguyen, 1999). Koreans prepare a traditional liquor (Lotus liquor) from the blossoms and leaves which they have found to have antioxidant activities useful for reducing oxidative stress and the risk of chronic diseases (Ku-Lee et al, 2005).

Ripe Lotus seeds also provide a spleen tonic (Follett and Douglas, 2003) and are used for their astringent action in the treatment of chronic diarrhea (Nguyen, 1999). In many Asian states the seeds are used as an antidepressant and to inhibit inflammation (Bi et al, 2006). Lotus plumele, also known as Lian fang, Lien Tze Hsin, and Lian xu, is the green germ of the mature Lotus seed and is rich in compounds such as alkaloids (demethylcolaurine, isoliensinine, liensinine, Lotusine, methylocrypalline, neferine, nuciferine, and pronuciferine), flavonoids (galuteolin, hyperine, rutin) and some microelements [Zn, Fe, Ca, and Mg] (Bi et al, 2006). The seed extracts have shown hepatoprotective and free radical scavenging effects (Ono et al, 2006). The Lotus plumule, removed from the ripe seed and sun-dried, is primarily used for nervous disorders, insomnia, high fevers with restlessness and hypertension (Nguyen, 1999). In Korea, Nelumbinis Semen (NS) or Lotus seed is one of the most well-known traditional herbal medicines used to treat cardiovascular symptoms (Kim et al, 2006). The flower receptacles contain proteins, carbohydrates, and a small amount of the alkaloid Nelumbine, used to stop bleeding and to eliminate stagnated blood. The flower itself contains alkaloids (isoliensinine, lotusine, methylcorypalline and demethylcoclaurine) with vasodilating effects (referine) and antihypertensive and antiarrhymic abilities [liensinine] (Ku-Lee et al, 2005). The stamens assist consolidation of kidney function and are particularly useful in the treatment of male sexual disorders and female leucorrhea (Nguyen, 1999). Pounded petals are used for syphilis, and the flower stalk combined with other herbs is used to treat bleeding from the uterus (Naturia, 2006).

CULTIVATION
Sexual and Asexual Propagation
Lotus can be propagated by seeds or by underground stem division. The Lotus seeds may survive for long periods of time (1,000 to 2,000 years). Their longevity can be attributed to the hard shells around the seeds, a nearly impermeable seed coat, small changes in the inner gas composition during long periods of storage, as well as, low changes in the concentration of their high dehydroascorbic acid (200 mg/100 g) content (Xueming, 1987). The method of propagation by seeds is mainly used in breeding new cultivars. The commercial sexual propagation is unusual because seeds are highly heterozygous. In Australia, imported seeds present problems due to low viability. In addition, germinated seedlings do not produce a crop until the following season (Nguyen, 1999). In Thailand, scientists micro-propagated buds from rhizomes. The aim of their research was to determine and compare efficacy of different irradiation methods to produce variegated phenotypes of Lotus (Arunyanart and Soontronyatara, 2002).

Rhizomes enlarged in the previous year are usually used for commercial cultivation (Masuda et al., 2006). This is considered the best, simplest method and they ensure a yield and a harvestable crop in one season. The enlarged rhizome found in N. nucifera acts as a dormant organ to aid in the survival of the plant under unfavorable circumstances. In China, according to the relationship among rhizomes, they are classified in 3 categories: parent, son, and grandson rhizomes. Chinese farmers use the entire parent as seed rhizomes. Rhizomes with a top bud, free of pest or diseases, are selected as seed rhizomes (Qichao and Xingyan, 2005). According to Xueming (1987), asexual propagation allows the original characteristics of the mother plant to be preserved, flowers to be enjoyed, and the Lotus "root" to be harvested in the same season. Nguyen (2001a) recommended the use of rhizomes with at least two segments sealed at either end by an intact node. He advised that transplanting should be done before rhizomes break dormancy, because plants transplanted after rhizomes have germinated do not establish as well. Although, rhizomes seem to be the preferred propagation method, sometimes apical buds or running stems are also used (Qichao and Xingyan, 2005). According to Nguyen (Nguyen, 2001a), the rhizomes are planted in a saturated media at an angle of 15 degrees with the shoot meristem buried under 5 cm of media. Propagation material should be grown in separate ponds. At the end of each growing season it is recommended to save 20 percent of the rhizomes for next season’s seed (Nguyen, 1999).

Soil Conditions
For production in containers and ponds several substrates have been suggested, however, Lotus prefers rich and fertile soil. Lake or pond bottoms containing large amounts of organic matter are the most suitable (Xueming, 1987). Some commercial stores suggest the use of a heavy clay loam or formulated soil for the growth of aquatic plants. Slocum and Robinson (1996) recommended the use of a soil so heavy that it would not float. This recommendation limits the use of most potting soil mixes found at garden centers. Shen-Miller et al. (2002) germinated hundreds-of-years-old seed in a 3:1 soil mix of clay soil and greenhouse soil (sphagnum moss, washed sand, and sandy loam in equal proportions). If the soil is heavy clay, roots can not penetrate and harvesting is more difficult. On the other hand, sandy soils lack binding sites for nutrients and have been reported to induce a rough flavor on the rhizomes (Nguyen, 2001a). Appropriate soil can be transported into the ponds. Optimal soil is a soft silt loam, free-form particulate matter (Nguyen and Hicks, 2004). Soils with correct organic matter (manure or well-rotted mulches) provide nutrients in an extended manner, a buoyancy to texture, good binding sites for nutrients, and prevent light penetration (Nguyen, 2001a).

Fertilization
Lotus field, lake, pond, or paddy deficient in fertility should be supplemented with various organic matters such as an oil-press cake, or composted and green manure (Xueming, 1987). The correct amount of fertilizer is dictated by the maturity stage of the crop. For example, plants reaching maturity and rhizome formation required more potassium and less nitrogen (Nguyen, 2001a). Tian et al. (2006a) fertilized ornamental Lotus by applying soluble fertilizer (20-10-20) applied once every 20 days (4-8 grams) after rhizomes had sprouted (coin leaves were visible on the water surface). In addition, Lotus plants responded favorably to increased fertilizer rates. Eight-gram applications increased root fresh weight, number of propagules, and expanded internodes (Tian et al. 2005).

Fertilization of young plants has to be carefully administered because they can be easily burned. It is recommended that the doses be split in 3-4 applications (Nguyen, 2001a). If seedlings are held for longer than 1 yr. in their pots, controlled-release fertilizer can be used after new leaves emerge in the spring. Osmocote Exact® tablets with 3% water soluble magnesium oxide 15-9-9, 8-9 months release at a rate of 5g per liter have been used successfully (Sayre, 2004). In India, growing media is enriched by incorporating well-decomposed cattle dung manure at a rate of 5 kg/m2, Neem (Azadirachta indica) cake (100 gm/m2), di-ammonium phosphate (25 gm/ m2) and muriate of postas (25 gm/ m2) as a basal dose 15 days prior to the planting (Goel et al., 2001).

Although animal manure has been suggested as a useful addition to such soil mixes, Shen-Miller and colleagues (2002) do not concur. In their previous studies, manure proved fatal to the young seedlings. They reported clay as an essential component for nutrient retention and as a minor nutrient source for Lotus culture. Slocum and Robinson (1996) suggested that well-rotted and composted cow manure can be used in the bottom-half if mixed one-part composted manure to two- or three-parts topsoil. In China, farmers use different combinations to fertilize the fields. In some cases, fields are enriched by adding 45,000-60,000 kg/ha of animal waste. In other cases, they combine 1,500 kg of bean manure + 15,000 kg animal waste per hectare. In other instances, they use 600 kg of special Lotus formulated fertilizer combined with 375 kg of NH4HCO3 / ha.

Container Management
Round containers are preferable because the tubers and runners can jam up in the corners of square planters (Slocum and Robinson, 1996). Seeds or seedlings can be planted in pots without holes which are 14-17 cm in diameter (Qichao and Xingyan, 2005). Researchers at Auburn University evaluated the effects of fertilization of container grown ornamental Lotus (‘Embolene’, #98 and #1). Lotus rhizomes were divided and planted in 7.5 gallon containers with no holes (Tian et al., 2006a). Three fifths of the pots were filled with rich and wet pond soil. Pots were irrigated 2 days later after the roots had extended and the plants were firmly attached to the mud (Qichao and Xingyan, 2005). Some commercial plant propagators recommend the growing of plants in Fabric Pond Pots or no-hole plastic containers to minimize maintenance (Water Garden, 2006). Large Lotuses perform at their best in large boxes, e.g., Aqualite pool [120x95x30 cm] or Super Tub [90x60x20] (Slocum and Robinson, 1996). At the National Botanical Research Institute, Lucknow, India, the Lotus germplasm collection is successfully grown in concrete tanks with a clay soil stratum up to 45 cm thick at the bottom of the tank (Goel et al., 2004).

Nguyen (2001a) reported that quality and availability play an important role in the success of Lotus cultivation. Although Lotus grows best in acidic soil of pH 4.6 (Shen-Miller et al., 2002), growth has not been affected by variation in water pH from 5.5–8.0. During a survey in Samaspur Lake, India, it was observed that Lotus was growing luxuriantly despite an alkaline pH of 9.0-9.3 (Goel, 2001). Adequate EC range has been reported to be 2.8–3.1 mS cm-1 and the plant has shown a tolerance for some levels of salinity in the water (Nguyen, 2001a).

Pond Management
This is a critical step in commercial production because once the pond is constructed, it can be difficult to change. Water management issues (acquisition, movement and storage) are primary considerations. Commercial producers should consider a deep reservoir on higher ground to feed the ponds by gravity and a water irrigation system, and a draining system (Nguyen, 2001a). The site for a pond needs to be relatively flat, expansive, and close to a reliable source of a large volume of fresh water (Nguyen and Hicks, 2004). Water availability should be considered seriously because the size of the pond is predicated on the amount of water available. As a rule of thumb, every acre requires 60,000,000 L/ha (Hicks and Haigh, 2001). The soil capacity to retain water is also very important. If the soil can not retain water the use of liners should be considered. In the Black Belt region, soils are rich in clay and can be compacted to form an impermeable barrier which allows the retention of water (Tilt, personal communication). The deepness of the pond should be carefully designed to prevent restriction of the rhizome’s growth and the consequent rhizome deformation (Nguyen, 2001a). Lotus is optimally grown in shallow ponds with a soil depth range of 20-30 cm to 1 m with a surface water range from 10-20 cm to 1.5 m (Nguyen and Hicks, 2004; Xueming, 1987). To prevent disease built-up and reduction of yield, crop rotation is being recommended. Taro (Colocasia esculenta), Sweet potato (Ipomoea batatas) or Yam bean (Pachyrhizus erosus) are good companion/rotation crops.

VEGETABLE PRODUCTION
Field Production

Lotus growth can be affected by temperature, photoperiod, and altitude (Qichao and Xingyan, 2005). In China, large quantities of Lotus are produced throughout the country from 19 degrees N to 47 degrees N and the growing area covers from the east coast to the Tian mountains. In some areas, Lotus is found growing as high as 2000 m above sea level (Follett and Douglas, 2003). Lotus requires at least 6 months with temperatures greater than 15 degrees C but the maximum rhizome growth occurs at temperatures over 20 degrees C (Follett and Douglas, 2003). Masuda et al. (2006) concluded that long-day-length accelerates rhizome elongation and upright leaf production, and short-day-length promotes rhizome enlargement and inhibits upright leaf production. In addition, they found that in high cultivation temperatures, more rhizome branches are produced (Nguyen, 2001a) and flower development is stimulated (Follett and Douglas, 2003).

Lotus grown in Europe and the United States are mainly used for ornamental purposes and rarely for food (Nguyen and Hicks, 2004). However, Lotus has been grown in the Imperial Valley of California and Yamaguchi (1990) believes that it can be successfully grown in the southeastern United States. In New Zealand, researchers are exploring the commercial production of cultivars in an area south of Whangarei which is located in a similar latitude to that of Ibaragi, the most important Japanese production area (Follet and Douglas, 2003). In Europe, temperatures are too cold for Lotus to bloom. However, blooms are produced in southern France, Spain, Portugal, Italy, Greece and some areas of former Yugoslavia (Slocum and Robinson, 1996). In China, Japan, Hawaii, India, and Korea the plant is cultivated for its rhizomes (Hanelt, 2001). In Mexico (Rogers and Redding, 2003) and Australia (Nguyen, 2001a), the crop has been explored to be grown as a new root crop for export markets. Lotus is grown in greenhouses, raised beds, containers and ponds.


Lotus grown out of season (winter) in greenhouses at Auburn University.


Rhizome of Nelumbo nucifera 'Embolene' sprouting.


Coin leaves.


Squat pots and top soil are very good for growing teacup lotus.


Seven gallon containers are more suitable for medium size Lotus (e.g. Nelumbo lutea).


Raised beds covered with liners are used for commercial Lotus multiplication and production.

Growing under glasshouses and in hot tunnels, a year-round supply can be ensured. Usually, the tunnels and glasshouses are erected over the existing beds (Follett and Douglas, 2003). Japanese farmers use greenhouses for early production of rhizomes (Nguyen, 2001a). In China, greenhouses are used to grow Lotus and to produce blooms out of season (Qichao and Xingyan, 2005).

Planting and Harvest
In China, early maturing varieties are planted closer than those that produce later (Xioming, 1987). In Australia, certified rhizomes with 2-3 segments are planted early in the spring. The propagules are placed in the mud at an angle. The water ponds have a depth of 30-50 cm and the water level is recommended to be set at 10 cm. Rhizomes are planted in rows spaced 1.8–2.7 m from each other with 0.7-0.9 m between plants. Seed rhizomes should be planted in a grid with an orientation so that the meristem heads are in the direction of the pond within its row (Nguyen, 2001a). Plant density varies from 4,115 to 7,936 plants per hectare.

Harvesting time and methods depend on the environmental conditions, which vary depending on the variety and country where the crop is cultivated. For example, in Cambodia, leaves and flowers are collected in April and the seeds are collected in August before the water rises (Lamberts, 2001). In China, rhizomes are harvested from August to March. In Taiwan, harvest is from June to November. In South Korea the rhizomes are collected from August to December (Nguyen, 2001a). In Japan, rhizomes are harvested from late-summer to the following spring (Masuda et al, 2006). Miwa (2006) describes the harvest as follows:

Sinking to their waists in mud, farmers dig out Lotus roots by hand and clean the muddy roots using water from wells”.
The edible Lotus rhizomes (60-120 cm long and 6-9 cm in diameter) have cream, light brown, or buff colored skin (Nguyen, 1999). They can be harvested after 120 days in warm climates and after 150-180 days or after the leaves die in cold climates (Yamaguchi, 1990). At harvest, the water is drained and the rhizomes are dug. In Japan, harvesting is done by hand (Nguyen, 1999). However, some Japanese farmers practice mechanical harvesting by using a backhoe with a specialized fork. This practice induces high wastage and damage to rhizomes. Also in Japan, high water stream is used to wash away the mud and expose the rhizomes (Yamaguchi, 1990).

Depending on the variety, location, and cultivation practices, yields vary. In Australia, yields from 8 to 40 tons/ha have been reported (Nguyen, 2001a ; Nguyen and Hicks, 2004). The Chinese have average productions of 22.5 t/ha, and the South Koreans reach productions of 31.8 t/ha (Nguyen, 2001a).

Packaging and Post-harvest Handling
Rhizomes after harvest are washed and trimmed.


Root ball of Lotus after having been washed.


Mature rhizomes ready for harvest.


Young rhizome actively growing after breaking dormancy.


Harvested propagules of ornamental Lotus 'Ms. Slocum'.


Harvesting propagation material.


Some cultivars have a very short dormancy period and start growing again before the harvest.

All soil residues, as well as lateral shoots, are removed. The highest grade rhizomes should be cut in lengths of three segments plus a portion of the fourth. There are four classes including large (L), medium (M), small (S) and second grade (O) (See Table 1).

The destiny of the product determines the type of packaging used. Japanese market requires the rhizomes to be packed in cartons of 1, 2, 4, 5, and/or 10 kg.

Lotus rhizomes must be handled with care because they are easily bruised and physical damage results in an immediate purple discoloration. In Japan, market quality rhizomes have to meet the following color, size and flesh characteristics (Nguyen, 1999):

1. Skin color is milky white.
2. Three segments of the rhizome have to have a diameter larger than 4 cm.
3. The flesh water concentration is high.
4. The texture is soft and crunchy.

Nguyen (2001a) recommended the use of Styrofoam boxes with sealable lids to maintain high humidity and avoid bruising and suggested the potential use of modified atmospheric packaging. Tian et al (2006a) reported a shelf-life of 20 days under room-temperature. In Australia, fresh Lotus rhizomes for the market which were kept in a non-refrigerated environment lasted 2-3 weeks (Nguyen, 2001a). Under those conditions, enzymatic activity accelerates with a consequent flesh-browning (Xin et al, 2002) and sugar degradation (Xiong et al, 2000). Lotus can be kept at temperatures between 3–7ºC. Lower temperatures induce chilling injury and surface scolding. In a recent study, Tian and his colleagues (2006a) tried different materials to extend the shelf-life of the rhizomes. By storing the roots at 5ºC storage-life was maintained for 45 days. High temperatures (>15ºC) accelerate disease development (Pseudomonas, Botrytis and Colletotrichum), weight loss; and rhizome dormancy resulting in an increase in carbohydrate degradation (Nguyen, 2001a).

Markets
The rhizomes are a food used extensively in China and Japan, sold whole or in cut pieces, fresh, frozen, or canned. Rhizome consumption in Japan represents about 1% of all vegetables consumed annually. Although it grows its own, Japan still has to import 18,000 tons of Lotus rhizomes each year, of which China provides 15,000 tons (Dharmananda, 2002). In 1995, Japan imported 1,347 tons of fresh and 14,887 tons of salted Lotus rhizomes (Nguyen and Hicks, 2004). Commercial production in Australia is very small because Australian quarantine regulations do not permit the importation of fresh roots; therefore, only frozen and dried Lotus are available. A study published in 2001 identified only 2 commercial Lotus producers with a production of 100 tons/y. The same study estimated a potential domestic demand of 1,080 tons (Nguyen, 2001a). In Taiwan, Lotus is traded in both rhizome and seed forms. Seed trade represents 5% of the entire industry but the price is twice that for rhizomes (Nguyen, 2001a). In cities such as Paiho, processed Lotus products provide good revenues. For example, in 1999, sales of the seeds and Lotus-root powder represented over US $9 million for the local economy (Yan, 2000). In the USA despite the large Asian and Asian-American population, the potential demand for Lotus is unknown.

There have been reports of imports from China to San Francisco. In 2001, a USDA study cleared the import of rhizomes from El Salvador, Honduras, and Nicaragua (Khan and Lima, 2001) and in 2003, fresh roots from Guatemala where allowed into the country (APHIS, 2003). Of the several countries in Asia where Lotus is cultivated and consumed, the Japanese market seems to offer the best opportunities for export. Its market produces 70,000 tons annually valued at approximately $800 million (Nguyen and Hicks, 2004). The potential for growing the crop (edible and ornamental varieties) for domestic markets remains to be explored. Fortunately, the Black Belt region has several advantages: soil, climate, water, and low land cost, all of which offer great incentives for further exploration.

Conclusions
Based on this research, the environmental conditions for growing Lotus in the southeast are very good.  The natural occurring species (Nelumbo lutea) is a good illustration of the potential for growing other related species and cultivars.  In addition, the capacity of the land and water resources of the State of Alabama for supporting a potential expansion of 10 times the current aquaculture industry opens the possibility for economic development for alternative aquatic crops.  Lotus' wide diversity of uses as vegetable, medicinal, and ornamental would suggest that there may be opportunities for growing this plant and supplying local demand, as well as providing export opportunities.  Therefore, Lotus is considered a great candidate which deserves to be evaluated.  However, more research on harvesting techniques, cultural practices, variety and cultivar development, evaluation of the native species, marketing potential, economic analysis and development of alternative uses (phyto-remediation and bio-fuel – Ethanol production) should be implemented.

References
* Armstrong, W. 2001. Economic plant photographs #2.
http://waynesword.palomar.edu/ecoph32.htm

* APHIS. 2003. USDA expands list of fruits and vegetables eligible for importation.
http://www.aphis.usda.gov/lpa/news/203/07/fruitvegimport.html

* Arunyanart, S. and S. Soontronyatara. 2002. Mutation induction by ? and X-ray irradiation in tissue-cultured Lotus. Plant Cell, Tissue and Organ Culture 70:119-122.

* BGCI. 2006. The conservation of the diversity of Nelumbo (Lotus) at the National Botanical Research Institute, Lucknow (India).
http://www.bgci.org/worldwide/article/0110/

* Bi, Y., G. Yang, H. Li, G. Zhang, and Z. Guo. 2006. Characterization of the chemical composition of Lotus plumele oil. Journal of Agricultural and food chemistry. 6 pages.

* Crews, J. and J. Chappell. 2006. U.S. Catfish Industry: situation in 2005 and outlook for 2006. Timely information. Agriculture & Natural Resources. Ag. Economic series. Auburn University.

* Bonniesplants. 2006. What to do when you receive your Lotus. 7 pages.
http://www.bonniesplants.com

* Dharmananda, S. 2002. Lotus seed: Food and medicine. Institute for Traditional Medicine, Portland, Oregon. 4 pages.
http://www.itmonline.org/arts/Lotus.htm

* Follett, J. and J. Douglas. 2003. Lotus root: Production in Asia and potential for New Zealand. Combined proceedings International Plant Propagators Society 53:79-83.

* Goel, A., S. Sharma, and A. Sharga. 2001. The conservation of the diversity of Nelumbo (Lotus) at the National Botanical Research Institute, Lucknow (India). Botanic Gardens Conservation International 3: 1-4.

* Hanelt, P. 2001. Mansfeld’s Encyclopedia of Agricultural and Horticultural Crops. Springer, New York.

* Hicks, D. and T. Haigh. 2001. Further considerations to growing Lotus –water. In: Shaping the future. Access to Asian foods. Department of Natural Resources & Environment and Rural Industries Research and Development Corporation. Australia. Issue 45.

* Kahn, R. and P. Lima. 2001. Importation of Nelumbo nucifera Gaertner (Waterlily, Lotus) as roots from El Salvador, Guatemala, Honduras and Nicaragua into the continental United States.

* Kew Gardens. 2006. Lotus. Culture online.
http://www.plantcultures.org.uk/plants/Lotus_landing.html

* Kim, J., M. Kang, C. Cho, H. Chung, C. Kang, S. Parvez, and H. Bae. 2006. Effects of Nelumbinis Semen on contractile dysfunction in ischemic and reperfused rat heart. Arc. Pharm. Res. 29: 777-785.

* Ku-Lee, H., Y. Mun-Choi, D. Ouk-Noh and H. Joo-Suh. 2005. Antioxidant effect of Korean traditional Lotus liquor (Yunyupju). International Journal of Food Science & Technology 40: 709-787.

* Magness, J.R., G. M. Markle, C. C. Compton. 1971. Food and feed crops of the United States. Interregional Research Project. USDA. Bulletin 828.

* Masuda, J., T. Urakawa, Y. Ozaki and, H. Okubo. 2006. Short photoperiod induces dormancy in Lotus (Nelumbo nucifera). Annals of Botany 97: 39-45.

* Miwa, S. 2006. Lotus root harvest in bloom. Daily Yomiuri Online.
http://www.yomiuri.co.jp/dy/columns/0003/seasons024.htm

* Mukherjee, K., K. Saha, M. Pal, and B. Saha. 1997. Effect of Nelumbo nucifera rhizome extract on blood sugar level in rats. Journal of Ethnopharmacology 58: 207-213.

* Naturia. 2006. Lotus.
http://www.naturia.per.sg/buloh/plants/Lotus.htm

* Nguyen, Q. 1999. Lotus – A new crop for Australian horticulture. IHD: Access to Asia – Newsletter (2): 1-5.
http://www.nre.vic.gov.au/trade/asiaveg/nlaf-04c.htm

* Nguyen, Q. 2001a. Lotus for export to Asia: An agronomic and physiological study. RIRDC Publication number 32. 50 pages.

* Nguyen, Q. 2001b. Agronomic and physiological studies on Lotus for export to Asia (Project DAN-125A). In: Shaping the future. Access to Asian foods. Department of Natural Resources & Environment and Rural Industries Research and Development Corporation. Australia. Issue 8.

* Nguyen, Q. and Hicks D. 2004. “Lotus”. In: The new crop industries. Eds. Salvin, S., M. Bourke and B. Hassalls. Department of Natural Resources & Environment and Rural Industries Research and Development Corporation. Sidney, Australia. Pages 78-84.

* Ono, Y., E. Hattori, Y. Fukaya, S. Imai, and Y. Ohizumi. 2006. Anti-obesity effect of Nelumbo nucifera leaves extract in mice and rats. Journal of Ethnopharmacology 106: 238-244.

* Pagels, W. 2006. Growing Nelumbo (Lotus) from seed & seedling cultivation.
http://www.victoria-adventure.org/Lotus/growing_from_seed.html

* Qichao, W. and Z. Xingyan. 2005. Lotus flower cultivars in China. China Forestry Publishing House. Beijing, China. 296 pages.

* Rogers, J. and J. Redding. 2003. USDA expands list of fruits and vegetables eligible for importation. Aphis.USDA.gov. Press releases.
http://www.aphis.usda.gov/lpa/news/2003/07fruitvegimport.html

* Sayre, J. 2004. Propagation protocol for American Lotus (Nelumbo lutea Willd.) Native plants Journal 1: 14-17.

* Shen-Miller, J., J. William, G. Harbottle, R. Cao, S. Ouyang, K. Zhou, J. Southon and G. Liu. 2002. Long-living Lotus: Germination and soil ?-irradiation of centuries old fruits, and cultivation, growth and phenotypic abnormalities of offspring. American Journal of Botany 89 92: 236-247.

* Slocum, P. and P. Robinson. 1996. Water Gardening: Water lilies and Lotuses. Timber Press, Oregon. 322 pages.

* The Water Garden. 2006. How to care for water lilies and other aquatic plants.
http://www.watergarden.com/pages/plant_care.html

* Tian, D., K. Tilt, F. Woods, J. Sibley, and F. Dane. 2005. Effects of soil level and fertilization on performance of container Lotus. Proceedings 52th Annual Research Conference. Southern Nursery Association. Atlanta, Georgia.

* Tian, D. 2006. Pictures from Auburn Lotus Research project. Dept. Horticulture, Auburn University. Auburn, AL.

* Tian, D., K. Tilt, F. Woods, J. R. Kessler and J. Sibley. 2006a. Postharvest longevity and quality of cooler-stored Lotus propagules. Paper submitted for publication. HortScience. 9 pages.

* Tian, D., K. Tilt, F. Woods, J. Sibley, and F. Dane. 2006b. Summary of development, introduction and marketing strategy to share Lotus in the Southeast United States. Proc. 13th Annual Conference Int. Plant Prop. Soc. Wakayama, Japan 13: 24-26.

* Tilt, K. 2006. Auburn Lotus Project. Dept. Horticulture. Auburn University, AL
http://www.ag.auburn.edu/hort/landscape/AU_Lotus_Project_Page.html

* Tullos, A. 2004. The Black Belt. Southern Spaces.
http://slouthernspaces.org/contents/2004/tullos/4a.htm.

* Xin, Y., L. Bi-feng, Z. Jing-yun, Z. Wei-feng. 2002. Progress in the research on post-harvest physiology and storage techniques of Nelumbo nucifera Gaertn. Guangzhou Food Science and Technology. 18: 50-53.

* Xiong, L., C. Huaixing and L. Shunyi. 2000. Studies on physiological and biochemical factors of Lotus roots during storing. J. Hubei University. 22: 180-191.

* Xueming, H?. 1987. Lotus of China. Wuhan Botanical Institute. 12 pages.

* Yang, J. 2000. Taiwan review.
http://taiwanreview.nat.gov.tw/fp.asp?xItem=558&CtNode=128

* Yamaguchi, M. 1990. Asian vegetables. p. 387-390. In: J. Janick and J.E. Simon (eds.), Advances in new crops. Timber Press, Portland, Oregon.

Tables

 

TABLE 1
Nutritional value of 100g (edible) rhizome and seeds (Nguyen, 2001a)
RHIZOMESSEED
ComponentRawBoiledImmature
raw
Mature
salted
Water (%)81.281.0 67.7 13.0
Energy (kcal)66.068.0 121.0335.0
Energy (kj) 276.0 285.0 506.0 1402.0
Protein (g) 2.1 1.8 8.1 17.1
Fat (g)0.00.00.21.9
Sugars (g)15.115.821.162.0
Dietary fiber (g)0.60.61.419.0
Calcium (mg) 18.0 17.0 95.0 190.0
Phosphorous (mg) 60.0 55.0 220.0 650.0
Iron (mg) 0.6 0.5 1.8 3.1
Sodium (mg) 28.0 19.0 2.0 250.0
Kalium (mg)470.0 350.0420.01100.0
Vitamin B1 (mg)0.09 0.070.19 0.26
Vitamin B2 (mg) 0.02 0.01 0.08 0.10
Niacin (mg)0.20.2 1.16 2.1
Vitamin C (mg) 55.0 37.0 0.0 0.0

 
TABLE 2
Classification of Lotus rhizomes for the Japanese market (Nguyen, 1999)
CLASSES RHIZOMES/CARTON
.1 kg 2 kg 5 kg 10 kg 5 kg dirt rhizomes
L <3.0 <5.0 <6.0 <13.0 <5.0
M <4.0 <6.0 7.0-12.0 14.0-20.0 6.0-8.0
S. . <13.0 >21.0 <9.0
O . . .<15.0* .

* Or rhizomes with a few damaged, misshaped or poor in color.

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