Seed and different methods of sowing

Different seed and their methods of sowing

1. Shoolini University
Dr. Arshdeep Singh
Department of Agronomy

2. (A) Seed and different methods
of sowing

3. Seed
A
basic
input in
agriculture

4. Definition-Seedisafertilizedripenedovuleconsistingofthreemainparts
namelyseedcoat,endospermandembryo,whichinduecoursegives
raisetoanewplant.Endospermisthestorageorganforfoodsubstance
thatnourishestheembryoduringitsdevelopment.Seedcoatistheouter
coverthatprotectsorshieldstheembryoandendosperm.
•Seedisafertilizedovuleconsistingofintactembryo,storedfood
(endosperm)andseedcoatwhichisviable&hasgotthecapacityto
germinate.
•Seedisanymaterialusedforpropagationwhetheritisintheformof
seed(grain)offood,fodder,fiberorvegetablecroporseedlings,tubers,
bulbs,rhizomes,roots,cuttings,graftsorothervegetativelypropagated
material.
•Theformationoftheseedcompletestheprocessofreproductionin
seedplants(startedwiththedevelopmentofflowersandpollination),
withtheembryodevelopedfromthezygoteandtheseedcoatfromthe
integumentsoftheovule.

7. Characteristics of good quality seed
Seed is the basic input in the crop production which should be of
good quality.
1.Seed should be genetically pure & should exhibit true
morphological & genetical characters of the particular strain (True
to type).
2.It should be free from admixture of seeds of other strains of the
same crop or other crop, weeds, dirt and inert material.
3.It should have a very high & assured germination percentage and
give vigorous seedlings.
4.It should be healthy, well developed & uniform in size.
5.It should be free from any disease bearing organisms i.e.
pathogens.
6.It should be dry and should contain 12-14% moisture.

8. Seed germination
•Epigeal Germination
–Cotyledons are exposed above ground
–Epicotyl and hypocotyls are also visible
–Cherry, soybean, radish
•Hypogeal Germination
–Cotyledons are buried in the ground
–Only epicotyl are visible
–Peach, pea, apricot
Two Different Types of Germination

11. SEEDRATE
Seedrateisthequantityofseedrequiredforsowingorplantinginanunit
area.
Theseedrateforaparticularcropwoulddependnotonlyonitsseed
size/testweight,butalsoonitsdesiredpopulation,germination
percentageandpuritypercentageofseed.

12. Sowing Time:Sowing is the placing of a specific quantity of seeds in the soil for
germination and growth while planting is the placing of plant propagules (may be
seedlings, cuttings, rhizomes, clones, tubers etc.) in the soil to grow as plants.
.Followrecommendedsowingdates.1.OptimumtimeofsowingforKharifcrop–
JuneorJuly
2.OptimumtimeforRabicrop-lastweekofOctobertofirstweekofNovember
Any fluctuation in optimum sowing time results in drastic yield reduction.
E.g.Wheat.
Depth of Sowing:
It influences the germination & emergence of seed.
Bigger seeds may be sown at a greater depth while small sized seeds at shallow.
Seed should be dropped in the moist zone.
InKharif,sowingshouldbeshallowandinRabideeperexceptpre-sowing
irrigation.Theoptimumdepthofsowingformostoffieldcropsrangesbetween
3-5cm.
•Shallowdepthofsowingof3-5cmisenoughforsmallseedslikesesame,
fingermilletandpearlmillet.
•Verysmallseedsliketobaccoareplacedatadepthofonecm.Boldseeded
cropslikecastor,groundnut,cotton,andmaizeetc.aresownat6-7cmdepth.

13. Sowing methods
1.Broadcasting
2.Dibbling
3.Drilling
4.Sowing behind the country plough
5.Planting
6.Transplanting

14. Broadcasting-Broadcastingisthescatteringorspreadingoftheseeds
onthesoil,whichmayormaynotbeincorporatedintothesoil.
Broadcastingofseedsmaybedonebyhand,mechanicalspreaderor
aeroplane.Broadcastingistheeasy,quickandcheapmethodofseeding.
Thedifficultiesobservedinbroadcastingareunevendistribution,
improperplacementofseedsandlesssoilcoverandcompaction.Asall
theseedsarenotplacedinuniformdensityanddepth,thereisno
uniformityofgermination,seedlingvigourandestablishment.Itismostly
suitedforcloselyspacedandsmallseededcrops.
Eg.Sesamum,methi,coriander,etc.aresownbythismethod.

15. Dibbling-Itistheplacingofseedsinaholeorpitmadeatapredetermined
spacinganddepthwithadibblerorplanterorveryoftenbyhand.Dibbling
islaborious,timeconsumingandexpensivecomparedtobroadcasting,but
itrequireslessseedsand,givesrapidanduniformgerminationwithgood
seedlingvigour.
eg.Castor,andHy.Cotton

16. Drilling -It is a practice of dropping seeds in a definite depth, covered
with soil and compacted. Sowing implements like seed drill or seed cum
fertilizer drill are used. Manures, fertilizers, soil amendments, pesticides,
etc. may be applied along with seeds. Seeds are drilled continuously or
at regular intervals in rows. It requires more time, energy and cost
compared to broadcasting, but maintains uniform population per unit
area.Rows are set according to the requirements

17. Sowingbehindthecountryplough-Itisanoperationinwhichseeds
areplacedintheploughfurroweithercontinuouslyoratrequiredspacing
byamanworkingbehindaplough.Whentheploughtakesthenext
adjacentfurrow,theseedsinthepreviousfurrowareclosedbythesoil
closingthefurrow.Depthofsowingisadjustedbyadjustingthedepthof
theploughfurrow.e.g.,groundnutsowingindrylandareasofTamil
Nadu.

18. Planting
Placing of vegetative part of crops which are vegetatively propagated
in the laid out field Tubers of Potato, mother sets of ginger & turmeric,
cuttings of sweet potato & grapes, sets of sugarcane

19. Transplanting -Planting seedlings in the main field after pulling out
from the nursery. It is done to reduce the main field duration of the
crops facilitating to grow more number of crops in an year. It is easy to
give extra care for tender seedlings. For small seeded crops like rice and
ragi which require shallow sowing and frequent irrigation for proper
germination, raising nursery is the easiest way.
eg. Paddy, vegetable, crops, tobacco, etc.

20. Vegetative propagation in
field crops

21. Plantpropagation:Plantpropagationistheprocessofcreating
newplantsfromavarietyofsources:seeds,cuttings,bulbsand
otherplantparts.
Sexual propagation Asexual propagation
Seedsandsporescan be used for
reproduction
Vegetative reproduction uses plants
parts such as roots, stems and leaves
Seeds are typically produced
fromsexualreproduction within a
species, becausegenetic
recombinationhas occurred. A plant
grown from seeds may have different
characteristics from its parents
Plants are produced using material
from a single parent and as such there
is no exchange of genetic material,
therefore vegetative propagation
methods almost always produce plants
that are identical to the parent.

22. Advantages and disadvantages of Sexual and Asexual
propagation
Sexual Propagation
Advantages
Less Expensive
Many parts can be produced
quickly
Crosses result in hybrid vigor
Avoids passing on some
diseases
Disadvantages
Not true to type to mother
plants
Take more time to come to
bearing
Pose problems for efficient
management
Asexual Propagation
Advantages
Less time is required to produce a
saleable (fit for sale) plant
Plants are genetically identical
The only way to produce some
plant varieties
Disadvantages
No, new variety can be evolved
Transmit viral diseases from plant
to plant.
Plants are comparatively short
lived
Requires technical skill

23. Techniques for vegetative propagation include:
1.Air or groundlayering
2.Grafting
3.Micropropagation
4.Stolon'sor runners
5.Storage organssuch asbulbs,corms,tubersandrhizomes
6.Strikingor cuttings

24. Layeringis a means of plant propagation in which a portion of an aerial stem grows
roots while still attached to the parent plant and then detaches as an independent
plant. Layering has evolved as a common means of vegetative propagation of
numerous species in natural environments. Layering is also utilized by horticulturists to
propagate desirable plants.
Ground layering-Ground layering or
mound layering is the typical
propagation technique for the
popular Malling-Merton series of
clonal apple rootstocks, in which the
original plants are set in the ground
with the stem nearly horizontal,
which forces side buds to grow
upward. eg. Guava
Air layering-Inair layering, the target region is
wounded, or a strip of bark is removed and
then encased in a moisture-retaining medium
such assphagnum moss, which is further
surrounded in a moisture barrier such asplastic
film. eg. pomegranate

25. Graftingis a horticultural technique whereby tissues from one plant are inserted
into those of another so that the two sets of vascular tissues may join together. This
vascular joining is called inoculation. The technique is most commonly used in asexual
propagation of commercially grown plants for the horticultural and agricultural
trades.
In most cases, one plant is selected for its roots and this is called the stock or
rootstock. The other plant is selected for its stems, leaves, flowers, or fruits and is
called the scion or cion. The scion contains the desired genes to be duplicated in
future production by the stock/scion plant
Eg. Mango, Sapota

26. Stolon: A Creeping, Aboveground Stem: A stolon or runner of Bermuda grass (Cynodon
dactylon). The stolon is an above-ground, trailing stem that typically produces roots at
the nodes where leaves and stems arise. Perennial grass also produces creeping,
underground stems called rhizomes. Another plant that spreads by means of stolons is
the strawberry.

27. Micropropagationisthepracticeofrapidlymultiplyingstockplantmaterialtoproducea
largenumberofprogenyplants,usingmodernplanttissueculturemethods.
Micropropagationisusedtomultiplynovelplants,suchasthosethathavebeen
geneticallymodifiedorbredthroughconventionalplantbreedingmethods.Itisalsoused
toprovideasufficientnumberofplantletsforplantingfromastockplantwhichdoesnot
produceseeds,ordoesnotrespondwelltovegetativereproduction

28. By Storage organssuch asbulbs,corms,tubersandrhizomes
a) bulbs
Eg. Onion
Eg. Garlic
b) By Tubers
Potato

29. c) By Rhizome in Ginger(Zingiberofficinale)
d) By corm in Gladiolus

30. Plant Propagation by Stem Cuttings
Propagation by stem cuttingsis the most commonly used method to propagate
many woody ornamental plants. Stem cuttings of many favorite shrubs are quite easy
to root. Typically, stem cuttings of tree species are more difficult to root.

31. Leaf cuttings-
Vegetative reproduction in
Kalanchoe pinnata

32. (B) Crop density and
different crop geometries

33. Plant density is the number of plants per unit area in a cropped field. It
indicates the size of the area available for individual plant.
Crop geometry is the pattern of distribution of plant over the ground or the
shape of the area available to the individual plant, in a crop field
Importance
(a)Plant Density and Yield: Biological yield increases with increases in
plant density up to a point and reaches a plateau with further increase
in density, thus no additional biological yield can be obtained. On the
other hand, the economic yield increases with increase in plant density
up to a point and subsequently decreases with increased in density.
(b) Plant Density and Growth: Plant height increase with increase in plant
density due to competition for light. Dense plant stands leads to reduction
in leaf thickness and alters leaf orientation. Dry matter production per unit
area increase with increase in plant density up to a limit, as in biological
yield.

34. CROPGEOMETRY
Cropgeometryreferstotheshapeofthespaceavailableforindividual
plants.Itinfluencescropyieldthroughitsinfluenceonlight
interception,rootingpatternandmoistureextractionpattern.Crop
geometryisalteredbychanginginterandintra-rowspacing(Planting
pattern).Widerspacedcropshaveadvantageunderthisgeometry
•Plantswhichrequiresnorestrictioninalldirectionsaregivensquare
geometry
•Usuallyperennialvegetationsliketrees/shrubsareunderthis
arrangements

35. (i)Squareplanting-Squarearrangementsofplantswillbemoreefficientinthe
utilizationoflight,waterandnutrientsavailabletotheindividualplantsthanina
rectangulararrangement.

36. (ii)Rectangularplanting-Sowingthecropwithseeddrill,widerinter-row
andcloserintra-rowspacingleadstorectangularity.Rectangular
arrangementfacilitateseasyintercultivation.Rectangularplantingmainly
suitsannualcrops,cropswithcloserspacingetc.,thewidersection(row)
isgivenforirrigation,interculturaloperationetc.
•Itisanarrangementtorestricttheendlessgrowthhabitinorderto
switchoverfromvegetationtotheproductivephase.
•Thismethodaccommodatehighdensityplanting
•Itcanfacilitateintercroppingalso.

37. (iii)Triangularplanting-Itisamethodtoaccommodateplantdensityunder
perennial/treecrops.
(iv)Miscellaneousplanting-Inriceandragitransplantingisdoneeitherinrowsorat
random.Skippingofeveryalternaterowisknownasskiprowplanting.