Ethiopian Kale (Kanzira/Kansera)-New

Introduction.

Brassica carinata, also known as Ethiopian kale or Abyssinian mustard, is a member of the Brassicaceae family and the genus brassica. The genus Brassica includes other essential exotic species such as cabbage, turnip, rape and swede, and kales. Ethiopian kale is believed to be native to the Ethiopian Highlands and is the African relative of kale from Europe. It has since spread to other parts of Africa and the world, including South and North America, Europe, and Asia. It is primarily grown in semi-arid regions, where its drought tolerance and short growing season make it an ideal crop.
Ethiopian mustard is cultivated as a multi-purpose crop in the Ethiopian highlands at altitudes between 1500 and 2600 meters. Several landraces exist that are used for their leaves, for their oilseed, as fodder, or a combination of these. Such landraces could be strongly branched with many small leaves, or plants could have just a few branches with larger leaves with a wide range of sizes and shapes in between.
Brassica carinata is a highly versatile plant with numerous applications. In most parts of Africa, B carinata is primarily used as a cooked leafy vegetable. The leaves and the tender stems are eaten in salads, boiled, and pickled. Despite its sharp odor, the cooked leaves have a delightful taste and are abundant in nutrients such as protein, fiber, and vitamins. The plant is often grown in mixtures of other traditional leafy vegetables and is eaten by preparing it with nightshade and spider plant.
Apart from being a food source, B. carinata is also utilized for its medicinal properties. The seeds of this plant are renowned for their efficacy in treating stomach aches, while the water used to boil the leaves is believed to have therapeutic benefits for diarrhea. Moreover, the seeds of ethiopian kale are used as a flavoring spice for raw meat in ethiopia. The seeds also contain glucosinolates that possess anti-carcinogenic properties. B. carinata has significant industrial value, as the oil derived from its seeds can be utilized to produce water repellants, waxes, and polyesters. Although the seeds of this plant contain high levels of erucic acid and glucosinolates, which are unsuitable for human consumption, they are highly productive and serve as a valuable source of animal feed.
(Maundu et al., 1999 ,Grubben et al., 2004, AVRDC & IPGRI, 2006).

Geographical Distribution

Brassica carinata is believed to have originated in Ethiopia approximately 4000 years BC, and it boasts a high degree of genetic diversity within this region. However, due to confusion in the literature regarding its distinction from Brassica juncea (L.) Czern., it is difficult to determine the exact distribution of Brassica carinata throughout Africa. The cultivation of Brassica carinata as an oil crop is restricted to Ethiopia, but as a leafy vegetable, it is often grown in East and southern Africa, less so in West and Central Africa (AVRDC & IPGRI, 2006).

Ethiopian kale is native to Eritrea and Ethiopia. It appears wild occasionally in field has been introduced in a number of African countries including: Gabon, Ivory Coast, Kenya, Tanzania, Uganda.

General information.
Species account

Brassica carinata is an erect, annual herb that grows to a height of 1.2 m or more. The stems and leaves are light green, pinnately lobed, and smaller compared to other brassicas). Flowers are yellow, borne in a long terminal inflorescence. They later bear a long green capsule that turns brown when dried and bears many small, pale to dark brown seeds, 1-1.5 mm in diameter. The time from sowing to the emergence of the Ethiopia kale seedling is about 5 days depending on the temperature and the soil moisture conditions. The plants develop an extensive rooting system. The plant sometimes occurs as a weed in cultivated areas and prefers fertile soils between 0 to 1600 m in elevation that receive 600 mm to 1600 mm of annual rainfall.
(Maundu et al., 1999, AVRDC & IPGRI, 2006).

Production of Brassica carinata for its seed is important only in Ethiopia. Production in Canada and the Mediterranean region is still experimental. As a leafy vegetable, it is mostly grown as a kitchen garden crop. However, in Tanzania, Malawi, Zambia, and to a lesser extent in Zimbabwe, it is also grown as a market crop. Its use as a leaf crop appears to decline because of higher-yielding leaf cabbage (Brassica oleracea) and leaf mustard (Brassica juncea). No statistical data on its production are known. (AVRDC & IPGRI, 2006).

Ecological information
Ethiopia kale is adaptable to a variety of environments thriving in highlands of up to 2600m with a cool climate and in lowlands with relatively warm and dry conditions. The vegetable crop does well in wide range of soils except in water-logged or saline soils. It grows best in the dry seasons when there are few pests and diseases. The optimum temperature ranges between 15 and 20 degrees Ethiopian kale' small seeds germinate rapidly in moist soils in partial shade or full sun (AVRDC & IPGRI, 2006

Agronomic aspects

Land preparation
Till land to fine tilth due to B. carinata's small seed size. African kale needs to be grown on free-draining soil with good soil fertility – well-decomposed cattle manure should be incorporated into the soil before planting 

Seed sources 
There are various seed sources for Brassica carinata, including commercial seed suppliers, agricultural research institutions, farmer-saved seeds, and seed exchanges. Commercial seed suppliers offer high-quality genetically pure seeds tested for germination rates and essential traits. Agricultural research institutions offer seed for a nominal fee, and farmer-saved seed is a cost-effective option but may lead to genetic drift. Seed exchanges provide diverse genetic material, but ensuring the seed's quality and viability is essential.

Planting 
It is advisable to plant on raised beds to reduce the incidences of damping off disease on the vegetable (AVRDC &IPGRI, 2006). Propagation is generally by seeds and rarely through cuttings. Planting is by direct seeding. It may be broadcasting or in rows – 15cm apart. Broadcasting is not encouraged as it results in uneven plant densities and makes it harder to carry out weeding, fertilizer, insecticide application, and harvesting. It is also more wasteful of seed and manure. Farmers may cover the seedbeds with grass to keep the surface moist and dark. When the cotyledons have spread after germination, this mulch is removed or placed next to the plantlets. Seedlings can be transplanted at the 4-leaf stage, about 5 weeks after germination. Depending on the variety, the field spacing is about 35-40 cm within and 50-60 cm between rows. Seedlings are planted with a spacing of about 75x50 cm for varieties with large leaves, as found in West Africa and Tanzania, and 50x50 cm for the small-leaved varieties in Zambia and Zimbabwe. When grown as an oil crop, seeds are sown directly in lines or broadcast when a short-duration leaf crop is aimed for.

Crop management
Ethiopian kale responds well to manure, and where possible, well-decomposed cattle manure should be incorporated into the soil before planting. Organic matter not only adds nutrients to the soil but also improves the structure of the soil, increasing its water-holding capacity. Manure may be applied at a rate of about ½ - 1kg/m². 
A recommended management is to cut the stems at 15 to 20cm height to encourage the proliferation of more and larger leaves. Frequent irrigation is needed for a good leaf yield. When the rains have stopped and irrigation is unavailable, plants will start to flower and produce seeds. When the crop is sown at the onset of the rains, attack by pests and diseases will be severe. To avoid such attacks, it is recommended that the crop be sown 5-6 weeks before rains are expected so that the crop can be transplanted at the onset of the rains.

Harvest, post-harvest practices and markets

a.    Harvesting 
The first harvest is done while thinning the seedlings from seeds broadcast at high density 6 weeks after sowing. The whole plant is uprooted, especially when the land is needed for another crop. The plants should be about 20cm in height, and thinning should be done to leave a spacing of about 35cm between plants. For a conventional crop, the first harvest takes place about 5 weeks after transplanting. Leaf harvesting is best done once in 2 weeks with 50% defoliation.

b.    Post-Harvest 
Ethiopia kale leaves are rather perishable – they wilt or become yellow if left on the shelf for more than a day. It is, therefore, advisable to only harvest small quantities at a time. To keep them for a long, leaves are kept moist inside a bag left in the shade or in a cool and dry place. When B. carinata is a whole plant with roots, place the roots in water so they can be kept for a few days. Traditionally, the leaves are dried in the shade for consumption in the dry season. Blanching can also be used to preserve the vegetables. Blanching is done by immersing the vegetable leaves in hot water at a certain temperature for a given period or steaming (Cookbook for traditional vegetables).

Seed Production
To produce a crop for seeds, plants must be selected early and left for late flowering. Large leaves, desirable consumption characteristics, good performance, and disease free are all characteristics to look out for. Such a selection is likely to lead to a significant increase in yields. Seedpods should be protected from birds, which split them open to eat the seeds. Pods should be harvested when fully dry, just before they open naturally, and shatter their seeds. The heads should be plucked off and dried on a large sheet in the shade, not in direct sunshine, as this could result in cooked seeds that will not germinate. Drying completely will usually take 3-5 days. Pods are crushed by hand or hit with a stick to release the seeds, then winnowed to clean them. Seeds should be stored in a clean, sealed container or polythene bag. 

Value addition and Market

Brassica carinata is a versatile crop that has attracted attention for its potential as a source of vegetable oil and biofuel. Additionally, the leaves of the plant are a nutritious vegetable, rich in vitamins and minerals and are grown commercially in various countries. In addition to Ethiopia, B. carinata is also grown as a commercial crop in other African countries, including Tanzania, Uganda, Kenya, Malawi, and Zambia. 
B. carinata is a highly desirable crop due to its agronomic superiority and ability to withstand frost compared to other oilseed crops and mustards. Additionally, it boasts a high oil content, large seed size, and lower rates of lodging and shattering in comparison to other species within the Brassica family. These favorable characteristics contribute to its overall marketability and potential for success in the agricultural industry.

Nutritional value and recipes

Brassica carinata is a nutrient dense leafy vegetable rich in vitamins, minerals, and phytochemicals. It is an excellent source of antioxidants, dietary fiber, and protein, and it has been shown to have numerous health benefits.
Ethiopian kale is also a good source of protein, with a protein content of around 25-30% (Mnzava and Schippers, 2007). This makes it an excellent choice for vegetarians and vegans looking for plant-based protein sources. B. carinata is also a good source of vitamins, including vitamin A, thiamin, riboflavin, niacin, and folate. Vitamin A is essential for maintaining healthy vision, skin, and immune function. Thiamin, riboflavin, and niacin are important for energy production and maintaining a healthy nervous system, while folate is necessary for cell growth and development. Furthermore, Brassica carinata has a low glycemic index, which means that it can help regulate blood sugar levels and may be beneficial for people with diabetes.

Table 1: Approximate composition and level of nutrients in raw and cooked Ethiopian kale (Brassica carinata)

Source (Nutrient data): FAO/Government of Kenya. 2018. Kenya Food Composition Tables. Nairobi, 254 pp. http://www.fao.org/3/I9120EN/i9120en.pdf
$ Draining the water several times leaches away water soluble nutrients significantly.
a Lewis, J. 2019. Codex nutrient reference values. Rome. FAO and WHO
b NHS (refers to saturated fat)
c https://www.hsph.harvard.edu/nutritionsource/water/
d British Heart Foundation
e FDA
f NIH
g Mayo Clinic

Complimentary recipes 
a.    Fried kanzira and leaf amaranth (terere) in fresh milk 
Kenyan dish
Ingredients
•    90 g of kanzira (B. carinata)
•    100 g amaranth
•    ½ to 1 cup of water
•    1 tablespoonful of cooking fat
•    1 small onion (60 g when)
•    1 medium-sized tomato (40 g when)
•    ¼ cup of fresh milk
•    Salt to taste (1 pinch)

Preparation
•    Remove stalks of the kale
•    Wash the vegetables separately, and drain and chop the Kanzira only. You may also chop the amaranth
•    Heat the water, add salt, then add the vegetable mixture (blanching). Blanch for 3 minutes. (Blanching is done to retain colour and nutrients). Remove immediately and dip in cold water, then chop
•    In a separate saucepan, heat the fat, add the chopped onion and fry it until it turns golden brown. Ensure onions do not burn
•    Add the chopped tomato and fry them until tender
•    Add the vegetables and stir-fry for five minutes
•    Add salt to taste
•    Vegetables ready to serve

Variation
½ cup Fresh milk or ¼ cream can be added after frying. Cook briefly after adding milk. It is usually better to add tomatoes to vegetables and avoid cooking tomatoes to retain more heat-sensitive Vitamins.
Remarks 
Although this mixture is bitter in taste, all age groups relish it. These vegetables are soft, and their cooking duration is short. This combination is more palatable when fried rather than boiled.

Source; Cookbook for traditional vegetables (IPGRI, 2006). 

b.    Figiri

Ingredients
•    2 handfuls (150 g) Ethiopian mustard leaves
•    One 50 g onion
•    2 (60 g) tomatoes
•    4 tablespoonfuls of cooking oil
•    3 tablespoonful groundnut flour
•    ½ cup fresh milk
•    Salt to taste
•    1 cup of water

Preparation
•    Select the tender leaves of Ethiopian mustard 
•    Wash in clean running water to remove soil and insects
•    Cut the midrib and shred the mustard finely
•    Wash, peel, and chop the tomatoes
•    Clean, wash and chop the onion
•    Fry the onion lightly, add tomatoes, stir and cook till soft
•    Add shredded mustard and stir till well mixed. Simmer while covering the pan for 2 minutes
•    Mix groundnut flour with milk, add into the vegetables and stir for 2 minutes
•    Season to taste and serve as a relish

Variation
•    Use coconut milk, water or cream instead of milk
•    Use peanut butter instead of groundnuts
•    Use meat instead of groundnuts
•    Can add carrots to the recipe

Remark
The vegetable cooks fast so do not overcook it.
 Source; Cookbook for traditional vegetables (IPGRI, 2006).