WELCOME

FLORAL BIOLOGY OF

IMPORTANT

CUCURBITS

Submitted by - Avisha Ram Budhani

1st semester M.Sc. (Horticulture)

ASPEE College of Horticulture & Forestry

Navsari Agricultural University, Navsari

Submitted to – Dr. Sanjeev Kumar

Assistant Professor

Department of Vegetable Science

ASPEE College of Horticulture & Forestry

Navsari Agricultural University, Navsari

FLORAL BIOLOGY OF CUCUMBER ( Cucumis

sativus L.)

Inflorescence

Inflorescence is cymose. Cucumber is monoecious i.e. male and

female flowers present on the same plant. Flowers are

bracteate, pedicellate, unisexual, actinomorphic, pentamerous

and epigynous.

Anthesis

The whole developmental process from the initial bud stage to

the stage when the flower is detached from the pedicel was

divided into 8 stages.

Opening and closing of the male flowers are mainly influenced

by the sunrise and sunset, that is, by light and the time of the

day.

• Anther dehiscence between temperature ranges of 20.5-

21.5°C.

• Pollen fertility was considerable up to noon and by afternoon

(2.00 PM) fertility was greatly reduced, and it was negligible

by evening.

• Stigma receptivity was for very short duration and

pollination should be carried out within 2 hours after

anthesis.

• Rise in temperature causes early drying of stigmatic

secretion. Different floral abnormalities like mixed

inflorescence, hermaphroditism, fusion, dimorphic female

flowers, reduction and increase in the floral parts were

observed.

•

Note the presence of a baby fruit behind the petals. The presence of the

baby fruit indicates it to be a female flower.

FLORAL BIOLOGY OF BITTER GOURD

(Momordica charantia L.)

• Studies on floral biology in Momordica charantia L. showed that

bitter-gourd plants started flowering 40 days after sowing and

blooming period varied from 68 to 76 days.

• The male flower buds took on an average 17 to 19 days, whereas

female buds took 21 to 22 days for their complete development.

• The anthesis started from 4.00 A.M. to 7.30 A.M. and flowers

became fully open from 6.00 A.M. to 9.55 A.M.

• The dehiscence of anthers happened within 6.10 A.M. to 8.55 A.M.

The male flowers dropped off on the same day at 6.00 P.M. to 7.00

P.M., while female flowers withered away next morning.

• Pollen grains of bitter gourd are round in shape. Their size may

vary within the varieties.

• Maximum pollen germination was observed in 20 per cent sucrose

solution.

• The stigmatal receptivity was found maximum at the time of

anthesis, beginning from 8 hours before anthesis and continuing

upto 12 hours after anthesis.

FLORAL BIOLOGY OF BOTTLE GOURD

[Lagenaria siceraria (Mol.)]

• The studies at IIHR, Bangalore, indicate that anthesis starts from

9 am and gets completed by 7 pm the same day.

• Anther dehiscence begins at 11 am and is completed at 2 pm the

same day.

• Stigma becomes receptive 24 hrs before anthesis and remains upto

24 hr after anthesis. Flowers remain open only for a few hours,

after which the petals wither.

• After 24 hrs the stigma loses its shine and becomes brownish and

increases by about 3mm in length, showing the start of fruit

formation.

FLORAL BIOLOGY OF MUSK MELON

(Cucumis melo)

• Flowers are large, yellow, fragrant and edible.

• Many sex forms – monoecious, gynomonoecious,

andromonoecious and perfect – are present in

melons leading to complete allogamy. Melons are

highly cross pollinated and honey bees are the chief

pollinators.

• Time of anthesis – 5:30 – 6:30 am

• Anther dehiscence – 5 – 6 am

• Pollen fertility – 5 am – 2 pm

• Stigma receptivity – 2 hrs before to 2-3 hrs after

anthesis

FLORAL BIOLOGY OF WATERMELON

[Citrullus lanatus (Thumb.)]

• The male flowers open first in the axil of 4th to

12th leaf and a few days later, female and

hermaphrodite flowers open.

• Most flowers open between 5:30 – 7 am. In

watermelon crosses, higher seed set was observed

when pollination occurred in the early morning

immediately after flower opening. Pollen kept at

room conditions for 5 hrs gave a lower seed set

than freshly collected pollen and after 30 hrs

completely lost viability.

FLORAL BIOLOGY OF POINTED GOURD

(Tricosanthes dioca Roxb.)

• Flowering starts from July. Flowers are white. Flower opens

in early morning and closes before sunset.

• Because of dioecy, the crop is highly cross- pollinated.

• Anthers are free, pollen sticky and hence is strictly

entomophilous.

• Male flowers took 16-19 days while female flowers took 10-

14 days from initiation to anthesis (when the anthers and

stigmas first became visible). Anthesis began at 19.00 to

19.30 h in female and at 19.30 to 20.00 h in male flowers.

Stigmas remained viable for 14 and 24 h in open and bagged

flowers, respectively.

FLORAL BIOLOGY OF RIDGE GOURD [Luffa

actangula (L.)]

• The sex forms in ridge gourd are monoecious, androecious,

gynoecious, gynomonoecious, and andromonoecious and

hermaphrodite.

• Flowers open in evening.

• Anthesis occurs between 5 – 8 pm. Anther dehiscence

between 5 – 8 pm. Pollen fertility is maximum on the day of

anthesis and lasts till 2 -3 days after anthesis. Stigma is

receptive 6hrs before to 84 hrs after anthesis.