WELCOME

TOPICImportance of Floral Biology of Some Minor Fruit Crops(like Aonla,

Bael, Ber, Jack Fruit And Jamun) in Perspective Of Crop Improvement

Speaker- Sharath. A. A Chairman- Prof. B. C. Das

Seminar Leaders- Prof. S. K. Sarkar and Prof. B. C. Banik

Course No: FRT- 649 Seminar-I Date- 06.02.2014

DEPARTMENT OF FRUITS AND ORCHARD MANAGEMENTFACULTY OF HORTICULTURE

BIDHAN CHANDRA KRISHI VISWAVIDYALAYAMOHANPUR, NADIA, WEST BENGAL

Topic division

• Introduction • Floral biology of Aonla• Floral biology of Bael• Floral biology of Ber• Floral biology of Jackfruit• Floral biology of Jamun • Conclusion

Introduction

• Floral biology has a significant contribution to sexual reproduction of flowering plants.

• Successful seed and fruit formation is largely dependent on pollination success rate, which subsequently depends upon the availability of good pollinators, pollen amount, pollen viability and stigma receptivity.

• Crop improvement programme mainly dependent on the knowledge of floral biology of the particular crop. In order to carry out the crop improvement programme successfully.

• Minor fruits have significant role in providing nutritional security and ecological balance.

• These fruit crops give handsome income to farmers with minimum input and care.

• To breed a new type/hybrid through artificial crossing or hybridization, the knowledge on floral biology is foremost important to a breeder, under the present climatic change.

Indian Gooseberry (Emblica officinalis G.)

• 2n=2x=18• Family: Euphorbiaceae• Origin: Tropical South East Asia particularly central and south

India.

• Rich source of Vitamin- C (600 mg/100 g)

• Antioxidative property - gallic acid and leucoanthocyanin.

• Draw backs – Long juvenile phase Self incompatibility Lack of inheritance pattern

Floral biology

• Male flowers appears in leaf axils through out the branch, while the female flowers are at distil end (Bajpai, 1968).

• Flower bud differentiation takes place in the first week of March and flowering period lasts for about 3 to 4 weeks.

• But in South India flowering takes place twice i.e Feb- Mar and June-July (Naik,1963).

• Anthesis takes place in evening time which varies from 5.50 to 7.45 P.M. according to cultivars.

• Sex ratio - 1:12 to 1:89. Maximum in Kanchan (1:12) and minimum in Chakaiya (1:89) (Shukla,et al., 2008).

• Anther dehiscence takes place soon or about 10 to 15min after anthesis.

• Female flowers open in stages and it takes about 72 hour to open completely.

• The stigma becomes receptive on the 3rd day of anthesis and remains receptive for another 48hours (Pathak and Pathak, 1993).

• Pollination is mainly through wind and hone bees.

• The fruit set may vary from 12-18% under open pollination and the maximum fruit set 27% was achieved through hand pollination (Bajpai, 1968).

• From flowering to fruit set it took 8-10 months. Again it varies with climatic condition and variety.

• Most of the flowers (>70%) were found to drop off within 3 weeks of flowering due to unfertilized ovaries & degeneration of ovules or on account of being males. (Das, B. C and Das, S. N., 2000).

Fig:1. Flowering twig.2. Male flower.3. Female flower.4. Fruits

Flowering at initial stage Full bloom stage

Fruiting stage

Bengal Quince (Aegle marmelos C.)

• x=9• Family: Rutaceae • Origin: India• The ripe fruits are rich in Riboflavin, protein, fat, minerals,

carotene, thiamine, niacin and vitamin C.

• The marmelosin is the active priniciple in bael fruits.

• The major draw backs in this crop are heavy fruit drop, fruit cracking and harvesting is difficult due to taller plant stature. Crop improvement programme should overcome these problems.

Floral biology

• Flowering occurs on one year old shoots.

• Flowers are hermaphrodite, regular, tetra or pentamerous and hypogynous.

• The inflorescence is much branched cymose or compound cymose type.

• The flowers having 4 or 5 sepals, which are 0.3cm in length,

corolla 4-5 and greenish white in colour.

• Stamens are varied from 43 to 54 in number, anther dehiscence is longitudinal (Singh, 1989).

• The stigma is capitate or fusiform the style is short and superior ovary.

• The flower development is in basipetal succession. There are three flowers on each secondary or tertiary branch.

• The inflorescence is having 6 to 72 flowers. The tree is in full bloom when 70-80% flowering has occurred (Singh, 1989).

• Generally the flowering takes place from May to July.

• The flowering varied depending on the climatic conditions of the region.

• In CIAH, Vejalpur (Gujarat), it was reported that flower bud emergence started from 30th April and continued up to 23rd June.

• In NDUAT, Faizabad, the flower bud emergence took place earliest on 22nd May (‘Narendra Bael 9’) and continued late upto last week of May (‘Narendra Bael 5’).

• Anthesis is from 2 am to 9 am. Maximum anthesis takes place between 6- 8 am.

• Peak anther dehisecence ranged between 6.30 to 8.30 am. High temperature and low humidity geared up the process of dehiscence.

• Stigma becomes receptive from one day before anthesis and continued till one day after anthesis.

• Maximum stigma receptivity (34.99%) recorded on the day of anthesis.

• Thus, for initiating the hybridisation work, the best time for doing artificial pollination is on the day of anthesis (Kanchan Kumar et al., 2000).

• Pollination is mainly through entomophily usually by honey bees.

• The duration from flowering to fruit harvest is 8-10 months (Das, B. C and Das, S. N 2003).

Cymose inflorescence

Flower buds about to open

Different stages from flowering to fruit formation

Poor man’s fruit (Zizyphus mauritiana L.)

• 2n=4x=48• Family: Rhamnaceae• Origin: India• Ber fruits are very nutritious and rich in vitamins C, A and

B- complex.

• In crop improvement Ber has some bottlenecks, they are: Polyploidy and incompatibility in its cultivars besides the

typical floral morphology.

The self and cross-incompatibility and long juvenile period are the hindrances for the systematic hybridization programme in this crop (Pareek et al., 2007).

Floral biology

• The duration of flowering in ber is prolonged and the time of blossoming largely depends on climatic conditions.

• The flower buds are borne on both mature as well as current season growth and the inflorescence is an axillary cyme.

• Most of the ber varieties are self-unfruitful and fruit set is poor without cross pollination.

• The flower opening continues for about two weeks with the central flower opening first. Individual flower comprises of 5 each of sepals, petals and stamens covered by a sheath, 2 or 3 celled ovary.

• The flowering period varies from early June to late November in different varieties under different agro-climatic conditions (Josan et al., 1980 ).

• The total duration of flowering varied from 68 to 94 days and it varied from cultivar to cultivar (Babu and Kumar, 1998) .

• Anthesis in ber is cultivar dependent. Seb, Ponda, and Illaichi - 7.30 to 8.30 am. Gola and Mundia - 12.00 pm to 1.00 pm (Pareek , 1983).

• Anther dehiscence in most of the cultivars started just after anthesis and is completed within 4 to 5 hours (Sharma and Kore, 1990).

• The stigma remains receptive upto 13 to 24 h (Desai et al., 1986).

• It is a cross-pollinated crop and pollination mainly takes place through honey bees, house flies and yellow wasps.

• Fruit set ranging from 3.56 to 27.88%. In Tikadi recorded the maximum fruit set (Mehrotra and Gupta, 1985).

• A very heavy fruit drop occurred immediately after fruit set because of ovule disintegration (Singh et al., 1991) it varies from 7.2% in cultivar Kaithali and maximum in Illaichi 95.63% (Raja, 1985).

• More than 50 per cent of the drop occurred when the fruits were <1.0 cm in diameter.

Flowering shoot

Different stages from flowering to fruit set

Community fruit (Artocarpus heterophyllus L.)

• 2n=4x=56 • Family: Moraceae• Origin: India

• On ripening the yellow flesh are eaten fresh or added to fruit salad. The large seeds are boiled and roasted and have a chestnut flavour.

• The unripe fruits (immature flesh) are used as a vegetable or

incorporated in curries and are also made into pickles (Purseglove, 1968).

Floral Biology

• All cultivated Artocarpus spp. are monoecious having separate male and female flowers.

• The inflorescence is called a spike.

• The female inflorescences arise from the trunk and older thick branches, either singly or in pairs, a distance away from the male spikes.

• Male spikes appear on the terminal ends of the branchlets.

(Purseglove, 1968).

• The ratio of male to female inflorescences varies from

96 - 4% (Srivastava., 1961).

• The stamen has 4 anthers and emits a sweet scent (Purseglove, 1968). This splits to expose a mass of sticky, spherical, yellow, pollen grains.

• The peak anthesis takes place between 1 pm and 3 pm and peak dehiscence occurs between 3 pm and 4 pm (Samaddar and Yadav, 1982).

• Stigmas tend to be receptive for 28-36 hours (Azad, 1989).

• Pollination – wind and insect.

• Lack of pollination may lead to the dropping of female spikes.

• Pollen viability in jackfruit is affected by different ranges of relative humidity and temperature.

• From spike appearance to fruit harvest it takes 90-110 days.

Flower opening in initial stage

Different stages from flowering to fruit set

Female flower

Male flower

Fully grown jackfruit

Indian Black berry (Syzygium cuminii S.)

• 2n=2x=40• Family: Myrtaceae• Origin: India• It is a one of the important but under exploited fruit crop of

India.

• Jamun is highly nutritive fruit, it’s a good source of iron, minerals, protein and sugar.

• Jamun products are effective for quenching thirst for diabetic patients.

Floral biology

• The flowering started from the last week of March and continued upto the last week of April.

• The flowers are hermaphrodite in nature.

• The inflorescences are generally borne in the axils of leaves on 5 months to one year old branchlets.

• Individual flowers are small and fragrant, widely campanulate calyx are irregularly dented above, disk conspicuous yellow, petals generally four, pink or greyish-white.

• Stamens many, white, style solitary and ovary two or three celled (Bajpai and Chaturvedi 1985).

• Maximum anthesis was observed at 4.00 to 5.00 pm.

• Anther dehiscence was reported to be 5.30 am to 9.30 am.

• Average number of anthers ranged from 60-65 per flower.

• Stigma receptivity was found maximum the day prior to anthesis and remained receptive up to 2 to 4 days after anthesis.

• It is a cross pollinated crop and the pollination is mainly through honey bees, house flies, wind and gravity.

• Maximum fruit set (32.6-36%) was obtained when pollination occurred one day after anthesis.

• The days taken from flowering to fruit set is about 119-126 days (Misra and Bajpai., 1975).

Different stages from flower anthesis to fruit set and harvest

Conclusion

• It is important to study the floral biology to carry out the crop improvement programme, which involves flower bud emergence, time of anthesis, pollen viability, stigma receptivity and fruit set, which varies with climatic conditions prevailing in the particular region.

• To develop desirable varieties it’s necessary to know about the floral biology of a particular crop.

• By knowing the floral biology of the crop we can carry out hybridization programme to induce desirable traits.

THANK YOU

Fruits for the future