1. Floral biology and crossing
techniques in groundnut
Manjappa
M Sc. Scholar
Dept. of Genetics & Plant Breeding

2. GROUNDNUT(Arachis hypogaea)
• 2n=4x=40 (Allotetraploid)
• O: Papilionaceae
• Synonym: peanut, Mungphalli, China Badam, Badam ,
wonder legume (for its flowering, pegging & pod formation
pattern)
• It is a herb, erect/trailing, photo insensitive.
• Used as oilseed, vine for fodder/manure

3. • Distribution: 80 countries, between 400
N to 400
S latitude in
tropical warm climate
• India is second in production after China
• In India G.nut ranks first(36%).soybean(28%),rape seed
mustard(23%), sunflower(5%)
• King of oilseed- is the largest oilseed in India in terms of
production as it accounts 35.99% of total oilseed production

4. Area & Production of Groundnut (Kharif and Rabi) in
India
year Kharif Rabi Total Area
(m.Ha.)
2008-09 5.62 1.55 7.17 5.29
2010-11(target) 7.22 2.46 9.68 -
Production in m.tonne

5. State-wise production(2009-10) & Area(2008-09)
State Production (.000
tonne)
Area (.000 Ha.)
Gujarat 1863 1795.4
Andra Pradesh 1024 1500
Tamil Nadu 875 327.3
Karnataka 512 694
Maharastra 414 254
Rajastan 357 321.5

7. • Although it is C3 plant, some of its physiological characters like
photosynthetic efficiency approaches the C4 plants
• 19% of total area under irrigated condition
• About 83% of total area is grown in kharif season mainly
rainfed(60% is sole crop)
• Soil type: well drained, light colored, loose, friable, sandy
loam soils well supplied with Ca & moderate amount of OM
• Heavy & stiff clays are unsuitable for rainfed G.nut as they
cause difficulties in pod growth & harvesting

8. Research centers
• International: ICRISAT(1972)-Sorghum, Pearl
millet, chickpea, pegionpea, G.nut (ICGS
1,44,11)
• National: NRC on Groundnut- JUNAGARH
(Oct 1 1979)

9. Nutritional qualities of groundnut
• Oil content 44-55%
• Protein content 22-32%
• Soluble sugars 8-14%
• Ca, Fe, Vit. B & E
• Oil contain 30% of Linoleic acid
• Cake contain 45-50% protein- rich in all amino acids except
Leucine & Methionine
• An adult requires protein-55g/day. G.nut supply 10%in India

10. Cont…
• It has antinutritional factors- Trypsin inhibitor & Phytic acid
(inactivated by boiling & roasting)
• Aflatoxin (mycotoxin): produced my Aspergillus flavus & A.
parasiticus, both are f. saprophytes invades G.nut before or
after harvest, during storage & transit
• During drought period pods are crack or damage by insects,
which makes way to fungi
• Aflatoxin cause liver cirrosis, cancer in animals(also human)
• Upper limit of aflatoxin for human use-30µg/kg

11. HISTORY
• It was first found in the Anion located in the
Peruvian coast near Lima in pre-historic
cemetery.
• Cultivated as early as 1200-1500BC (carbon
dating investigation)
• It’s cultivation was widely distributed in S
America
• Krapovickas: Peruvian type carried from
American West coast Mexico Philippines
China & India(16th
C)

12. • Origin: A. hypogaea – Bolivia & N-W Argentina(Krapovikas-1969)
• Wild proginatorss: Smalt Itle(1978)- probable ancestors of A.
hypogaea are-
A. duranensis (A genome)
A. ipaensis (B genome)
• According to centromeric bands & RFLP data A. villosa & A.
apaensis are diploid proginators of A. hypogaea & A. monticola
• Arachis Genus has more than 70 wild species existing in nature

13. CLASSIFICATION
• Based on growth habit
a) Spreading: branches are spreading, main shoot may erect or
bent
b) Semi-spreading: main shoot always erect
c) Bunch: branches makes acute angle with the erect main shoot

14. Varietal classification of Groundnut
Virginia Peruvian runner Valensia Spanish

15.  4 cultivated species of Arachis are-
Diploid species (2n=2x=20)
A villosulicarpa (N-W Brazil)
A repens (fodder & cover crop)
Tetraploid species (2n=4x=40)
A glabrata (fodder & cover crop)
A hypogaea (oil seed) - Segmental amphidiploid
33 species named
A. monticola is only a wild Arachis taxon which can be crossed
with A hypogaea to produce fertile progeny

16. Distinguishing characters Spanish-valensia & Verginia groups
Characters Spanish-Valencia Virginia
Seed size Medium to small Medium to big/very big
Seeds/pod 2-4, rarely 5 2, rarely 3
Seed dormancy Very little / absent Medium to long
Flowers on main shoot Present Absent
Branching pattern Continuous Alternate
No. of branches Few to medium Medium to heavy
Length of primary branch Smaller than main shoot Bigger than main shoot
Growth habit Bunch Spreading / semi-
spreading, bunch
Duration(days) 100-125 135-175
Leaf color Light green Dark green
Peak flowering stage 6-10 weeks 8-12 weeks
Leaf tip shape Round Acute
Growth of plant after pod
formation
Absent present

17. Floral Biology

31. Floral Biology
• Inflorescence: solitary or raceme
containing flowers in the axils of
cataphylls
• Flower: Zygomorphic, sessile, looks
pedicillte late when peg starts
developing(hyponthium)

32. Std petal: very in color, central area(std crescent)
has darker lines radiating from base to the
periphery.
Wings: leathery yellow, wrap around keel
Keel: pale yellow, closely wrap around stamens &
upper part of the style & stigma
calyx: 5 Sepals(lobed), 1-seperated,justaposed to
keel & 4-fused except at tip

33. • Stemens: 10 monodelphous
Globose filaments are initially
shorter than oblong one, later
become equal or longer than
them after pollination

34. • Ovary: present at the base
of hyponthium, superior, 2-
4 ovules, occasionally 5,
rarely 6
• Style: two sharp bends
• Stigma: club shaped,
protrude above anther &
gets pollinated after
dehiscence.
• Receptive before anthesis,
enclosed in keel petal(self
poll.), but when it is
exerted out effect cross
pollination(1-3.9%), based
on season, bees & variety.

35. Floral diagram & Formula
Br., Brl., %, KK (4)+1, C5, A (10) , G 2

36. Flowering
• A flowering branch never occurs at the same node as a
vegetative branch.
• Indeterminate growth, better at good sunshine
• Anthesis - 5.30 to 7.30am
• Stigma becomes receptive about 24 h before anthesis
and its receptivity persists for about 12 hours after
anthesis
• Pollination is affected 7-8 hrs before blooming
• If anther dehiscence gets affected due to cloudy
weather, the style continues growth & stigma become
protrude & pollinated by alien pollen through insect

37. Flowering cont…
• Pollen grains are smooth, oval, and sticky, Fertilization occurs
about 6h after pollination.
• All flowers don not end up in forming pods
• 2/5 flowers- shed off at beginning
• 2/5 flowers- do not form pod even after pod formation
• On an avg. 1/7 forms pod

38. Pegging

39. Pegging cont…
• within 7 days after fertilization the intercalary meristem below the
ovary starts become activate & female whorl located on the third
internode also starts getting enlarged
• This in later stages takes the shape of thick root & carry the
fertilized ovary in its tip – called peg
• Movement geotropic penetrate soil up to 7cm depth & become
diageotropic
• The pod formation will start after growth of peg stops
• Time taken by peg to reach the soil surface is 2-8 days in bunch
type & 5-10days in spreading type

40. Pegging cont…
• Only 44% pegs form pod
• Soil should be soft to facilitates peg insertion
• Pods are slightly or deeply constricted (depends on variety,
soil-type, season)

41. Difference between bunch & spreading type
Characters Bunch type ( DAS) Spreading type( DAS)
Flowering 20-24 24-30
Pegging insertion in soil 28-32 34-40
Pod devt.(Starting) 33-37 39-45
Starting of pod formation 88-92 99-105
Fully developed pods 105 135
Peak vegetative growth 15 DAF 28-43 DAF & 59-74 Days
Max. flowering time 20-30DA Ist flowering 35-45 DA Ist flowering
Flower duration 20-36 DAF 31-80 DAF
NO. of flowers/plant 98-137 40-250

42. Crossing technique
• Emasculation will be doing at evening hours(4 pm
onwards)
• Select those buds which are bulged, which are about to
open in immediate morning
• Bend the lower lip of calyx(separated one), carefully
open wing petals & make a slight slit on keel petal to
open the stamens
• Remove all fertile anthers(8) to see that stigma should
not damage
• Close the emasculated bud with its petals to avoid
contamination

43. • Pollination will done in the next morning between 7-10am.
Collect anthers from male plant & squeezed by needle on
slide, pollinate emasculated bud with needle
• Tie the small thread to calyx tube for identification
• Success is judged by the resultant peg emergence, developing
peg should carry a withered flower & the piece of thread
attached earlier

44. Checking for success

45. Imp insect pest
• Leaf minor (Aproerema modicella)
• White grub (Holotrichia sp.)
• Hairy catterpillar (Armsacta albistraga)
• Termite (Microtermus sp. & Nasutitermus sp.)

46. Imp diseases
• Early leaf spot (Circospora arachidicola)
• Late leaf spot (phaeoisariopsis personata)
• Rust (Puccinia arachids)
• Pea nut necrosis
• Root knot nematode
• Bacterial leaf spot

47. Imp varieties
• Spanish type: MS 1, GG 2, J 11, TG 11, ICGS
11,TMV 57981
• Valencia type: MH 2, Kopergao-3, TMV 11
• Virginia bunch: Kadiri-2&3, TMV-6,8&10
• Virginia runner: M-13, GG-11,F-230
TMV-1,3&4

48. Breeding Objectives
Breeding for-
• for-High yield
• Moisture stress(drought)- 80% of area under rainfed
• Earliness
• Pest & disease resistance
• Fresh seed dormancy- Spanish type lacks
dormancy(sprouting of seeds when caught by rain)
• increased seed viability
• High temp., cold, salinity, Al toxicity tolerance-(opt
temp.30-350
C)

49. Cont…
• Increased biological N2fixation(BNF)-By proper choice of
combination of host genotype & Rhizobium strain we can
increase N fixation(G.nut fix 124kg/annum)
• Resistance to lime induced chlorosis: common in calcarious &
alkaline soil
• Quality characters: Large seeded /confectionary types (ICGS
49) – high protein, sucrose & less oil content
• Oil content & quality(linoleic acid)
• Resistance to Aflatoxin contamination(ICGV 86168)

50. Cont…
• Nutrition Use Efficiency
• Efficient adaptation to different cropping systems
• For fodder- Arachis pintoi & A. glabrata

51. Future Thrusts
• Yield level is at plateau in developing countries because of
lack of effective breeding programmes.
• Pest, diseases, drought stresses. Use of transgenics will be an
imp tool in breeding for stress resistance
• Enhancement of gene pool through an extensive use of the
whole gamut of core germplasm variability, so that genes in
the pool are utilized fully. Identification of markers can be an
imp component in gene pool enhancement
• Breeding for quality aspects
• Some of the wild species have 46-63% oil content as
compared to cultivated(43-56%), so still scope to improve.