Sorghum varu gaitonde.

Floral biology and breeding techniques

1. PRESENTATION ON SORGHUM FLORAL
BIOLOGY
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2. INTRODUCTION
Common name: jowar, jola, jonna,
Scientific name :Sorghum bicolor L.
Monech
Chromosome number: 2n=2x=20
Origin :Ethiopia
Progenitor : S. arundinaceum
(2n=2x=20)
S. sudanese (2n=2x=20)
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3. TAXONOMY
Kingdom : plantae
Family : Poaceae
Genus : Sorghum
Species : bicolor
Other related species : guinea, caudatum, kafir,
durra.
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4. FEATURE OF SORGHUM CROP
IT IS C-4 PLANT.
IT IS GROWN EXTENSIVELY IN TROPICAL AND
SUBTROPICAL ENVIRONMENT
MORE SUITABLE FOR RAIN FED FARMING
FIFTH POSITION AT WORLD LEVEL BOTH IN
AREA AND PRODUCTION AFTER WHEAT,
MAIZE, RICE , BARLEY.
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5. BOTANY
Sorghum is a annual or perennial grass.
Root : fibrous and extensively
developed, either non rhizomatous or
weakly rhizomatous well developed
rhizome are found in Johnson grass (S.
halepense).
Stem : erect, made up of a series of
alternative nodes and internodes.
Pith may be sweet or insipid, juicy or
dry.
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6. contd….
Leaves :are arranged on stem in two rank alternating on opposite
side.
Number of leaves varies from 7-28.
Panicle : varies from lose to compact .
The panicle has a central axis divides into nodes and internodes
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7. FLOWER STRUCTURE
Inflorescence of the sorghum varies from compact head to open
panicle.
Spikelet occur in pair (one large sessile and small
pedicelled) except for the terminal spikelet.
Flowers called a florets & they are enclosed by two bracts called the
Palea and Lemma (Lower Bract).
The Lemma encloses the Palea and the Flower Organs.
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8. contd……
Florets occur in groups called Spikelet.
Each spikelet is subtended by bracts called Glumes.
The Perianth of each floret is represented by two transparent scales
called Lodicules.
There are generally 3 stamens and Gynoecium with two hairy
stigmatic lobes. The Stigmatic trichomes are designed to capture
wind-borne Pollen
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13. FLORAL BIOLOGY
sorghum inflorescence blooms in early morning in
basipetal manner
the anther and stigma push out as the glumes
open.
Stigma are receptive from 1-2 days before
blooming to 8-16 days after blooming depending
on the variety and the climatic condition
Stigma before the anther dehiscence are
subjected cross pollination (<5 to 50%)
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14. contd….
Cross pollination is greater in variety with open panicle than in
compact panicle varieties.
Anthessis begins from 2 a.m. and opening continues till 8 a.m. and
may prolong to 10 a.m.
Fertilization takes 1 to 2 hours after pollination
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15. SELFING
bagging
Isolation
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16. CROSSING TECHNIQUE
Important crossing tools
Hand emasculation:
Emasculation by hot water treatment
Use of male sterile line
Plastic bag/mass emasculation techniques
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21. POLLINATION
Pollens are collected in paper for few hours after
dehiscence and collected pollens are uniformly
spread on the emasculated panicle
Fertilization takes place 2 hours after pollination
Embryo is formed 12 days after fertilization
Development of embryo and endosperm
continues along with starch accumulation for
about 30 days
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