This document provides information on the flower morphology and floral biology of black gram. It discusses that black gram is a self-pollinated crop grown in warm temperatures and medium rainfall. Its flowers open in the morning and self-pollinate from bud stage through anther dehiscence at night. Cross-pollination can be achieved through emasculation and manually rubbing donor anther pollen on the stigma of emasculated buds.
3. Black gram is basically a warm season crop, but in India
it is grown in both summer and winter, up to 1800 m
altitude.
It is quite drought resistant but intolerant of frost and
prolonged cloudiness.
It is normally grown in areas with an average
temperature of 25–35°C and an annual rainfall of 600–
1000 mm.
In higher rainfall areas it may be grown in the dry season
on residual moisture. Heavier, well-drained soils such as
black-cotton soils with pH 6–7 are preferred, but black
gram is also grown on lighter soils.
4. • Black gram was most probably domesticated in India
from its wild ancestral type.
• At present black gram cultivation is of major
importance in India only, but it is also grown to some
extent throughout tropical Asia.
• In Pakistan, Bengladesh, India, it is growen as a
pulse crop
• It is grown in the United States and Australia mainly
as a fodder crop.
5. It would be worthwhile trying black gram on a much larger
scale in tropical Africa.
Because of its highly nutritious seeds and its wide
ecological applicability.
Germplasm diversity needs to be exploited to obtain
suitable cultivars for Africa.
9. Genetic resources and breeding
About 2100 accessions of black gram are maintained by the
National Bureau of Plant Genetic Resources (NBPGR),
New Delhi, India, at its various research stations.
The USDA Southern Regional Plant Introduction Station,
Griffin, Georgia, United States, holds 300 accessions.
Asian Vegetable Research and Development Centre
(AVRDC) in Taiwan maintains a collection of 200
accessions.
10. cytology
Somatic chromosome number in urdbean is 2n=22
Avarge length of chromosome is 1.70 micron
Mejority of chromosome are metasentric in nature I.e. arm-ratio is
1.00-1.75
Fem chromosomes are reported to have secondery constriction
(gupta &sharm,1991
Vigna mungo is successfully crossed with
(1)Vigna sublobata
(2)Vigna trilobata
(3)Vigna umbellata
(4)Vigna angularis. But reciprocal cross is possible only through
embryo rescue technique (Gosal & Bajaja,1983)
11. morphology
(1)Plant is an erect or sub-erect,
diffusely branched herbaceous annul
(2) Stem is 20 to 80cm
long,occasionally trrailing type.
(3) Leaves are trifoliate with long
petiole
(4) Pods are erect or sub- erect, buff to
dark brwn at maturity
(5) Seeds are oblong with square
ends, mostly block,Green seeds are
also found
12. Flowers : are bisexual, papilionaceous, small;
bracteoles are linear to lanceolate, exceeding the calyx;
calyx : is a campanulate it includes 5sepals;
corolla: is a yellow in
colour(5petals), standard petal is a 12–16 mm wide,
2wings petal is about as long as standard, 2keel petals
spirally coiled with a terminal horn-like appendage;
stamens: are 10 in number, 9 united and 1 is free
(Diadelphous)
Flower morphology
13. Floral biology
•Flowers begin to open between 6 to 7 am
•Flower is continues for an hour
•Flower is remain open till noon & gradually close,being
completely closed by 2 to 4pm
•Pollination accure at bud stage
•Anthers dehisce between 9 pm to 3 am
•Petals wil shedin the folowing mornng
14. Selfing techniques
(1)It is a self pollinated crop
,the occurrence of natural
cross pollination is
neglegible i.e less then
5%
(2)Natural cross pollination
is mainely by insects
(3) In order to ensures
100% selfing, bag the
flower before antesis
15. BLACK GRAM IS A ESSENTIALLY A
SELF POLLINATED CROP.THERE
ARE TWO METHEDOS INVOLED IN
CROSSING OF BLACK GRAM
(1) EMASULATION
(2) POLLINATION
16. (1) Selection of flower bud
(2) Flower bud should held between fore and thumb finger
(3) Dissecting needle is inserted just under the standrd obliquel
y along the top of the bud
(4) The left side standard & left wing are pushed outward away
from the bud
(5) The left keel is removed in pieces
(6) Exposed anthers are removed
17. Pollination
Take out stamen from freshly opened flowers
Rubbed anthers againset the stigma of the emasculated bud
Pllination should be immediately after emasculation gives good
pod set