This document discusses evolutionary trends observed in different varieties of Datura plants. It describes single corolla Datura (SCD), double corolla Datura (DCD), and triple corolla Datura (TCD) varieties and the morphological differences between their floral structures. DCD varieties are found to have larger fruits and seeds than SCD and TCD varieties, as well as higher seed germination rates, making DCD a better choice for large-scale cultivation. The document also explores how studying floral mutations in Datura, such as increases in corolla or stamen numbers, could provide insights into engineering larger fruits and seeds in other crop plants through similar mutations.
1. EVOLUTIONARY TRENDS IN DATURA
AND SELECTION OF CROP IDEOTYPES
By
Shri Niwas Singh & Shyam Narayan
Department of Genetics & Plant Breeding,
B.R.D. P.G. College,
Deoria, U.P. – 274001, INDIA.
Email: niwas_mdra@bsnl.in
For Kanke presentation
2. THE HARDY DHATURA (DATURA)
emerging from
plaster on the
basement of a
building.
A common
medicinal weed,
Favourite of Lord
Shiva.
16. TERMS FOR FLORAL ORGANS
Sl.
No.
Collective
term
Term for
individual unit
Symbol
in FF
1 Calyx okányiqat Sepal okány K
2 Corolla nyiqat Petal ny C
3 Androecium iqeax Stamen iqadslj A
4 Gynoecium tk;kax
Pistil, Carpel
L=hdslj] v.Mi G
17. BESSEY'S DICTA VIS-A-VIS EVOLUTIONARY
TRENDS IN DATURA FLOWERS
Primitive (TCD, DCD) Advance (SCD) Comment
polymerous flower structure oligomerous reduction
Petaly apetaly reduction
apochlamydeous perianth gamochlamydeous -
Actinomorphy zygomorphy -
similar dissimilar -
Hypogyny epigyny -
Apocarpy syncarpy -
Polycarpy oligocarpy -
endospermous seed without endosperm Large seed
small embryo large embryo Large seed
polystemonous oligostemonous yes
apostemonous synstemonous yes
powdery pollen massed pollen
Monoclinous (bisexual) Diclinous (Unisexual)
monoecious dioecious
31. DCD WITH TEN STAMENS
C(5)+(5) A5x2
Near SVPG College,
Deoria.
32. THE ABC MODEL
A genes alone specify sepals,
A & B genes together specify petals,
B & C genes together specify stamens, &
C genes alone specify carpels.
33. THE DIFFERENCES
In case of Datura also, something might be
happening in B &/or C class genes because
double flowers arise often due to mutations in
C class of genes. But these mutations are
increasing fruit and seed size. Remember
the Arabidopsis AGAMOUS -- Sterile. Therefore,
work on such mutations (models) and increase the
yields of fruits & seeds. …--> total biomass.
34. CAN WE USE?
Decipher the mechanism of corolla
doubling & tripling…...i.e., Androecium
to Corolla transformation (stamen to petal)
and stamen doubling.
Use that mechanism in doubling & tripling
the corollas in ornamental flowers. Corolla
is usually the most showy part of flowers.
35. OTHER PROBABLE USES OF COROLLA
DOUBLING & TRIPLING...
May be, we can change self-pollinated
crops like wheat & paddy to cross-pollinated
crops and exploit heterosis in
more efficient way. Lodicules (the perianth)
are equivalent to corolla (+calyx) that could
be increased in size & number to change
flowering phenology of plants and hence
from self-pollinated varieties to cross-pollinated
varieties.
37. OTHER PROBABLE USES …
Double the number of stamens in
Calotropis and harvest double
amount of the nectar.
Crocus sativus (kesar),
Kamal kesar etc.
38. COMPARATIVE DATA 2011
Parameter SCD DCD TCD
Average
plant height
in cm
94.13
(n=15;
range 65-140)
110.11
(n=19;
range 50-163)
64
(n=14;
range 34-115)
39. COMPARATIVE DATA 2011
Parameter SCD DCD TCD
No. of
fruits/plant
13.6 21.1 14.5
Average fruit
size in cm3
Small, oval,
30.16 (n=10;
range 12-45)
Large, globose,
63.95 (n=35;
range 41-100)
More oval than
SCD, 24.74 (n=10;
range 14-41)
41. COMPARATIVE DATA 2011
Parameter SCD DCD TCD
Pericarp
thickness
SCD >SCD =SCD
Adherence of
seeds to placenta
SCD Tightly
attached
=SCD
42. TABLE 2. DIFFERENCES AMONGST SCD, DCD AND TCD 2012
Parameters SCD DCD TCD
1. Plant height Tall Small Tall
2. Novelty SCD Novel Novel
3. Distinctiveness SCD Distinct Distinct
4. Uniformity Uniform Fairly uniform Less uniform
5. Stability Stable Fairly stable Less stable
6. Fruit size Small Large Small
7. Fruit shape Oval Globose More oval
8. Fruit orientation Down facing Up facing Down facing
9. Competitiveness Strong Weak Strong
10. Growth rate SCD >SCD =SCD
11. Thalamus Normal Extended More extended
43. CONCLUSIONS
Since DCD is performing better than SCD & TCD
under cultivation, it would be wise to select &
recommend it for large scale cultivation. DCD
seems to be a week competitor in wild.
Population ideotypes are week competitors.
SCD & TCD are competing well under natural
conditions. However, it is still unclear why TCD
is so rare.
SCD could be collected from wild. No need to
cultivate.
44. TOMATO: 5, 6, 10 FLORAL ORGANS
Number of floral
organs is
increasing in the
same whorl.
Fruit size BIG.
Notice that all
the four organs
are being
affected by this
mutation.
45. CONCLUSION
LOOK FOR SIMILAR MUTATIONS THAT
INCREASE FRUIT SIZE, SEED SIZE AS
PER CROPS’ NEED, i.e, increase the
resource allocation towards the
desirable sink.