Cucumber cultivation

CUCUMBER HYBRID PRODUCTION TECHNIQUES

BOTANY

Botanical Name  :  Cucumis sativus L.

Family                 :  Cucurbitaceae

Chromosome No. : 2n  = 2x =  14

Mode of Pollination : Cross pollinated

Flowering Habit  : Monoecious

ORIGIN

Ø  Originated in India

Ø  Introduced in Europe by Romans.

Appeared in France in the 9th century, in England in the 14^th century and in North America by the mid-16th century

IMPORTANCE

Ø  Low in Saturated Fat and very low in Cholesterol and Sodium.

Ø  Good source of Vitamin A, Pantothenic Acid, Magnesium, Phosphorus and Manganese

Ø  Very good source of Vitamin C, Vitamin K and Potassium

Ø  A large portion of the calories come from carbohydrates

Production wise ranking of cucumber

Rank	Country	Area (Hectares)	Production (Tonnes)
1	China	988545	40,709,556
2	Iran	75119	1,811,630
3	Turkey	59000	1,739,190
4	Russia	66300	1,161,870
5	USA	53460	883,360
6	Ukraine	51700	860,100
7	Spain	8100	682,900
8	Egypt	28238	631,408
9	Japan	12100	587,800
10	Indonesia	53400	547,141
63	Pakistan	2983	40551
	Source: UN Food & Agriculture Organization(FAO)

Area wise ranking of cucumber

Rank	Country	Area (Hectares)
1	China	988545
2	Cameroon	157000
3	Iran	75119
4	Russian Federation	66300
5	Turkey	59000
6	United States of America	53460
7	Indonesia	53400
8	Ukraine	51700
9	Iraq	39100
10	Egypt	28238
11	India	23900
63	Pakistan	1200
Source: UN Food & Agriculture Organization(FAO)

Yield wise ranking of cucumber

Rank	Country	Yield (T/Ha)
1	Spain	84.3
2	Japan	48.6
3	China	41.2
4	Turkey	29.5
5	Iran	24.1
6	Egypt	22.4
7	Russia	17.5
8	Ukraine	16.6
9	USA	16.5
10	Indonesia	10.2
63	Pakistan	13.6

PRODUCTION TECHNOLOGY

Time of sowing	Mid February and July
Growth period	Mid February to June July to November
Time of harvesting (# picks)	April to June (15-18) September to November (15-20)
Fertilizer requirements	NPK (35:30:25)
Irrigation requirements	16-20
Soil requirement	pH = 6.0 to 7.0 Loam, fertile and well drained soil
Suitable area in Punjab	Multan, Sahiwal, Bahawalpur and Lahore divisions
Varieties of Pakistan and India	Pakistan =  (Local cucumber ) India       = (Ender, Kakri, Long special, Rani,                    Tripti and Desi long)

NUTRITIONAL PROFILE OF CUCUMBER PER 100 G
Energy Water Protein Fat Carbohydrates Dietary fiber Sugars Calcium  Iron	65 kJ (16 kcal) 95.2 g 0.7 g 0.1 g 3.6 g 0.5 g 1.7g 16 mg 0.3 mg	Magnesium Phosphorus Potassium Sodium Vitamin A Vitamin C Vitamin B1 Vitamin B2 Vitamin B3	13 mg 24 mg 147 mg 2 mg 105Iμ 2.8 mg 0.03 mg 0.03 mg 0.09 mg

USEFULNESS IN DISEASE AND NUTRITION

Pulp and seed have cooling effect, tonic, diuretic and the former is beneficial in chronic or acute eczema. Cucumber seed has a number of ayurvedic uses. Its oil is good for brain and body.

Value Added Products of Cucumber

Ø  Pickle 

Ø  Cosmetics

Ø  Sliced

Ø  Canned

Ø  Dried

Ø  Blend with juice drink

Ø  Pepsi Ice Cucumber

Cucumber Pickle

Ice Cucumber Drink

Blend with juice drink

Face Moisturizer

MAJOR GROWING COUNTRIES

China contributes about 60% of  global production.

Turkey, Russia and Iran are other contributors.

FLOWERING PATTERN

|  High temperature and long days promote male flowers

|  Low temperature and short days promote female flowers

|  Male flowers appear earlier

|  Female flowers appear on the lateral as well as on the main stem and can be recognized by the ovary at the base of flower

 

Modes of Pollination

Ø  Honey bees are the main pollinators of Cucumber and other insects also contribute.

Ø  Cucumbers can also be produced without pollination by a process called Parthenocarpy

PARTHENOCARPY

•       The natural or artificially induced production of fruit without fertilization of ovules. The fruit is therefore seedless.

TYPES OF CUCUMBER PLANTS

Monoecious cucumbers

        These cucumbers bear both male and female flowers on the same vine. You can grow just one plant and still get fruit. The plants will bear the male flowers first before producing the female flowers.

Gynoecious cucumbers

        These high yielding plants produce only female flowers. The flowers require pollination to set fruit, so at least one monoecious cultivar needs to be grown with them to provide pollen.

        When seeds are packaged, 10 to 15% of the seeds in the package will be the monoecious cultivar to ensure the gynoecious type will be properly pollinated.

Parthenocarpic cucumbers

        Plant this type if you want to get seedless fruits without pollination. You can plant a single plant of this type and still get fruit. Many of these cultivars were developed for greenhouse culture where there are no bees or other pollinators available.

TYPES OF CUCUMBER FRUITS

Ø  Pickling cucumber

Ø  Slicing cucumber

Ø  Dutch cucumber

Ø  Beit Alpha cucumber

Ø  Asian cucumber

CLIMATIC REQUIREMENTS

Ø  Warm season crop grow well in temperature ranging from 25-30 °C

Ø  Temperature below 18 °C and above

         35 °C cause reduction in growth

Ø  Any stress in the plant, such as increased   plant populations and low moisture, will tend to increase male flowering in even gynoecious lines.

Breeding Objectives

Development of hybrids/variety with:

Ø  Early fruiting

Ø  High female to male flower ratio

Ø  Green fruit colour

Ø  Uniform long cylindrical fruit shape

Ø  Less seeds at edible maturity

Ø  Fruits free from bitterness

Ø  Biotic and abiotic stress resistance

BREEDING METHODS

•       Population Development

–      Recurrent Selection

•       Line Extraction

–      Pedigree breeding

–      Single seed descent

–      Back cross breeding

–      Hybrid Development

Heterosis/Hybrid Vigour

Considerable heterosis has been manifested for

•       number of fruits (Hayes and Jones, 1916).

•       early and high yield (Solanki et al., 1982)

PLANT GROWTH AND DEVELOPMENT

•       Vine Types:

        The growth habits of cucumbers are important in breeding programs that utilize different vine types so that hybrid yields might be increased.

•       Cucumber is an annual with a prostrate vining type of growth, habit

•       Three distinct types of vine growth

Indeterminate vines:

        Grow continuously until the plant dies, with the internodal length relatively constant throughout the length of the vine.

Determinate vines:

        Similar Internodal length as indeterminate plants but vines terminate in a flower cluster.

Compact vines:

        Considerable shorter internodes than either of the other two types.

Monoecious cucumbers generally go through three phases of sex expression

1) Initial period

female flower

                        when only male flowers are produced.

        2) A long period when equal numbers of male and female flowers are borne.

        3) A final relatively short phase when female flowers largely predominate.

GYNOECISM IN CUCUMBER

•       Gynoecious sex expression is used to develop cucumber hybrids in which only female flowers are produced.

•       This trait is linked with parthenocarpic  genes and do not require pollination for fruit set.

male flower

•       Use of silver nitrate (AgNo3), 50-100 ppm or silver thio-sulphate, 25-50 ppm on gynoecious plants at 2-3 leaf stage produces lots of staminate flower, which are used to multiply the seed of gynoecious plants.

•       The growth regulator ethephon induces female flowering and causes monoecious plants to exhibit gynoecious expression.

FRUIT SET AND DEVELOPMENT

Ø  In monoecious, fruits developed at nodes.

Ø  Fruit setting at a lower node may inhibit or delay fruits from setting at subsequent nodes.

Ø  Fruit size and shape is usually related to the number of seeds produced by pollination.

Ø  In normal fruit setting successfully, pollen transfer from the male flower must be occurred to the female flower.

Poor pollination results in fruit abortion, misshapen fruit, or poor fruit setting

MECHANISM OF HYBRID DEVELOPMENT

Ø  Development, maintenance and multiplication of parental lines

Ø  Assessment of combining ability between the parental Lines.

Ø  Hybrid seed production utilizing selected parental combination(s).

METHODS OF HYBRID DEVELOPMENT

Inbred line Production:

Ø  Inbred seeds are produced in the inbred parent by pollination of their pistillate flowers with staminate flowers on the same plant (self-pollination), or an adjacent plant (sib-pollination) through insects e.g. Honey bees or through hand pollination.

Ø  The inbred parent is planted in multiple rows in an isolation block or insect-proof cage.

Ø  For isolation blocks /fields at least one mile distance should be from the nearest cucumber field.

Ø  In monoecious parent inbred line, sufficient seed is obtained due to presence of both staminate and pistillate flowers on each plant.

Ø  For gynoecious, the plants will have to be treated with a growth regulators e.g., gibberellic acid 3 (GA3), silver nitrate, and amino ethoxyvinyl glycine (AVG)soon after seedling emergence to make them phenotypically monoecious.

Inbreeding results in:

Ø  Increases homozygosity

Ø  Decreases size of plant

Ø  Decreases number of fruits per plant

Ø  Decreases size of fruit

Ø  Decreases number of seeds per fruit

Selfing techniques

Ø  Selection of male flower and tying its petals.

Ø  Selection of female flower and tying its petals

Ø  Pollination and again tying the petals of female flower

Ø  Tagging the pollinated flower

Ø  Picking of ripened fruits and collection of seed

Hybrid Production

Ø  By pollination of pistillate flowers of female parent with the pollens of staminate flowers in the male parent by  insects e.g., Honey Bees or through hand pollination.

Ø   The two inbred parents are planted in an isolation block or insect-proof cage in alternating rows, with 1 or 2 rows of the female parent for each 1 row of the male parent.

Ø  For monoecious hybrid seed production, the rows of female inbred should be treated with ethrel 3 to 6 times (once/week) starting at the full cotyledon stage.

Ø  Ethrel will cause the plants in the rows of female parent to convert to gynoecious sex expression.

Ø  The first few fruit harvested from the plants in the rows of female inbred will contain hybrid seed until the plants change back to monoecious sex expression. The longer the plants are treated with ethrel, the longer they will stay gynoecious.

Ø  At flowering, the sex expression of the plants in the rows of female inbred should be checked to make sure they are gynoecious.

Ø  Off-type (rogue) plants can be removed from the isolation block or cage.

Ø  If the number of off-type plants is large, the seed increase should not be used from that hybrid production block.

Ø  About six weeks after fruit set, or 13 weeks after planting (depending on growth temperature), the cucumber fruit will turn from green to white, yellow or orange. The fruit will become softer and a few will have started to rot. At that time, fruit will be harvested from the rows containing the female parent. Rows containing the male parent will not be harvested, since they will be the male parent inbred, not the hybrid

SUCCESS RATE

ripend fruit

The success rate of selected hand pollination is about 15-20%, so a large number flowers are self pollinated to achieve desired number of fruits

Hybrid seed extraction

•       Fruit will be put into a bulk seed extractor that crushes the fruit between rollers, and separates the fruit pieces from the seeds. Yield will be about 200 seeds per fruit from a good field).

HOW TO AVOID BITTERNESS

Ø  Keeping the soil moist at all times will ensure they are not bitter.

Ø  It is recommended that you side-dress the plants with nitrogen fertilizer as they begin to vine.

Cucumber vines may be trained to climb trellis netting or a fence; hanging cucumbers will develop straighter fruits and will be more uniformly colored

seed drying

seed cleaning