inbred hybrid technology in maize, dmr

Inbred-Hybrid Technology in Maize

Directorate of Maize Research

(Indian Council of Agricultural Research)

Pusa Campus, New Delhi 110 012 (India)

INBRED-HYBRID TECHNOLOGY IN MAIZE

Directorate of Maize Research(Indian Council of Agricultural Reserach)

Pusa Campus, New Delhi 110 012, IndiaWebsite: www.maizeindia.org, Email: [email protected]

Phone: 011-25841805, 25842372; Fax:011-25848195

Sain DassManivannan A

J KaulAvinash Singode

JC SekharChikkappa GK

Correct citation:Sain Dass, Manivannan A, J Kaul, Avinash Singode, JC Sekhar and Chikkappa GK. 2010. Inbred-HybridTechnology in Maize. DMR Technical Bulletin 2010. DIRECTORATE OF MAIZE RESEARCH, PUSACAMPUS, NEW DELHI -110 012 (INDIA). Technical Bulletin No. 2010/1, pp.52.

Copy right:All rights reserved. Source of information has to be acknowledged. No part of this publication may bereproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical,photocopying, recording or otherwise, without the prior written permission of the publisher.

Published in 2010

Published by:Director,DIRECTORATE OF MAIZE RESEARCH, PUSA CAMPUS, NEW DELHI -110 012 (INDIA)

Frontpage cover :East and Shull (Photographs), Single Cross Hybrid

Backpage cover :Hybrid seed production plot, Single cross hybrid cob, Single cross hybrid

Printed by:Alpha Printographics (India)Mobile : 9811199620, 9999039940

S. No. Particulars Page No.

1. Introduction 12. Maize Breeding Activities in India 33. Impact of Single Cross Hybrid Maize 44. Maize Research Network in India 65. Inbred-Hybrid Technology – Historical Perspectives 86. Strategies for the Development of Inbreds 107. Isolation 118. Seed Increase 139. Inbred Line seed Production and Maintenance 1410. Crop Management Practices 1611. Roguing 1712. Diagnostic Traits 1713. Seed Production 2514. Characterization of good seed/pollen parent 2715. Crop Protection 3016. Crop Inspection 3117. Minimum seed standards in Maize 3318. Germplasm 3419. Public Private Partnership 3520. Seed Village Concept 3621. Single Cross Hybrids of Specialty Corn 38

Annexure-I i - vi

CONTENTS

(Directorate of Maize Reserach) 1

Inbred Hybrid Technology in Maize

Introduction

The concept of Hybrid vigour given by G.H.Shull in 1908; still considered one of the greatest

achievements in the history of plant breeding. Maize breeding is the science of maize cultivar

development. Heterosis has been successfully applied by maize breeders worldwide to adapt and

improve germplasm sources for desirable traits. Single Cross Hybrid technology has been widely

adopted because of its high yield, uniformity, easy production methods, ability to withstand biotic

and abiotic stresses and food and nutritional security. In India a coordinated emphasis has been

laid on various aspects of maize breeding activities viz., development of genetically diverse,

productive, inbred lines with good per se performance and resistance / tolerance to biotic and

abiotic stresses; testing of large number of 2-parent crosses at different locations under multi

location program; easy, economical and efficient commercial seed production technology and

quality seed production, improved package practices and demonstrations especially on farmers

field. Coupled with free exchange of germplasm including inbreds between the centres and re-

orientation programs of the breeders, the paradigm shift in breeding strategy has paid rich dividends

in terms of vertical as well as horizontal expansion of maize witnessed over the years. Currently in

India, the crop is grown on area of 8.17 million ha with production of 19.73 million tons having an

average productivity of more than 2.4 tons/ ha, contributing about 9 % to the Indian food basket.

The focused research in Single cross hybrids helped in addressing several issues of biotic and

abiotic stresses viz., lowering water table, rising temperature, etc. The success story of single

cross hybrid in US Corn belt is well known. Its impact has been realized in China, Brazil, Canada

and many other countries too. Even in USA with cultivation of Open Pollinated Varieties the

productivity remained less than 2 tons/ha. And further, the results were not encouraging with the

coverage of 100% area under Double cross hybrids and the productivity was only 3.5 tons/ha over

a period of 25 years (1936-1930). But with the adoption of Single cross hybrid technology in 1960s

USA productivity increased 3.5 tons/ha (1960) to 9.68 tons/ha(2008). The annual increase in

productivity with 100% coverage under Double cross hybrid was only 60kg/annum in 25 years and

with Single cross hybrid cultivation the productivity per annum is more than double in a period of

50 years. Parallel to USA in India the productivity remained less than 1 ton/ha for many decades

continued. After shifting to Single cross hybrid technology (2006-2008), in India has witnessed

30% increase in production and 27% increase in productivity within two years with the coverage of

20% area under Single cross hybrid. There is also 15% annual increase in production and more

than 12% increase in productivity. India became net importer to potential exporter. This is the

visible impact of single cross hybrid technology. Keeping the above points in view this manual has

been prepared to popularize the Inbred-Hybrid technology among maize researchers, seed

producers, manufacturers of maize products and farmers. This manual complies all historical

perspectives occurred in maize breeding, Inbred-Hybrid technology, Seed production technologies,

Seed village concepts and Public Private Partnership in Single cross hybrid seed production.

2 (Directorate of Maize Reserach)


INBRED-HYBRID TECHNOLOGY IN MAIZE

Maize (Zea mays L.) is the most widely distributed crop of the world being grown in tropical, sub-

tropical and temperate regions up to 500 and from sea level to more than 3000m under irrigated to

semi-arid conditions. Being a versatile crop, it adapts easily to a wide range of production

environments. In India, maize is the third most important cereal after rice and wheat that provides

food, feed, fodder, and serves as a source of basic raw material for the number of industrial

products viz., starch, protein ,oil, alcoholic beverages, food sweeteners, cosmetics, bio-fuel, etc.

No other cereal can be used in as many ways as maize. Virtually every part of the plant has an

economic worth. The grain can be consumed as human food, fermented to produce a wide range

of foods and beverages, fed to livestock, and used as an industrial input in the production of

starch, oil, sugar, protein, cellulose, ethyl alcohol, etc. The leaves, stalks, and tassels can be fed

to livestock, either green (in the form of fodder or silage) or dried (in the form of Stover).The roots

can be used for mulching, incorporated into the soil to improve the physical structure, or dried and

burned as fuel. It occupies an important place as a source of human food (24%), animal feed

(11%), and poultry feed (52%), starch (11%), brewery (1%) and seed 1% (Fig.1). In India, maize is

cultivated over 8.17 million ha with a production of 19.73 million tons having an average productivity

of more than 2.4 tons/ha, contributing about 9% to the Indian food basket. No other cereal crop

has shown the high growth rate as of maize (Fig. 2).

Fig.1. Current utilization pattern of Maize in India



MAIZE BREEDING ACTIVITIES IN INDIA

Maize breeding in India has gone through many phases since the inception of AICRP on maize in

1957. However, the year 1988-89 has been a threshold year with the launching of single Cross

Hybrid (SCH) breeding program and adoption of New Seed Policy. SCH breeding activities witnessed

many positive changes and accomplishments in generating vital scientific information as well as

commercial products. Now research efforts have been focused on the development of high yielding

single cross hybrids for different agro-ecological regions of the country seeing the strength of

heterosis for high yield and tackling the problems posed by biotic and abiotic stresses. This has

been duly supported by development of vigorous genetically diverse inbred lines that have good

performance per se as well as in cross combinations. The major mandate therefore, is to evolve

and disseminate inbred-hybrid technology. Now research efforts have been focussed mainly on

the development of high yielding single cross hybrids for different agro-ecological regions of the

country seeing the strength of heterosis for high yield and tackling the problems posed by biotic

and abiotic stresses. This has been duly supported by development of vigorous inbred lines that

have good performance per se and in cross combinations. The major mandate therefore, is to

evolve and disseminate inbred-hybrid technology. A coordinated emphasis has been laid on various

aspects of maize breeding activities in the country, viz., development of genetically diverse,

productive, inbred lines with good per se performance and resistance / tolerance to biotic and

Fig.2. Area, Production and Productivity of Maize in India



Fig.3. USA Corn yield and cultivar types

abiotic stresses; testing of large number of 2-parent crosses at different locations under multi-

location program; easy, economical and efficient commercial seed production technology, and

demonstrations especially on farmers’ fields.

IMPACT OF SINGLE CROSS HYBRID MAIZE

Maize is being a versatile crop, in order to harness its yield potential several genetic and

agro-technique improvement strategies have been suggested in the past and present viz., open

pollinated varieties(OPVs), composites, double top cross, double cross, three way crosses, four

way crosess etc., since none of these strategies were able to harness full heterotic potential

finally, single cross hybrid technology have been advocated. The impact of single cross hybrid

technology was clearly visible in USA, China, Canada and many other countries. In USA with the

cultivation of land races/open pollinated varieties (OPVs) the productivity remained 1.98t/ha(Fig.3).

Even the results were not encouraging with the coverage of 100% area under double cross hybrids.

From 1936 to 1960 the productivity did not cross 3.5t/ha in period of 25 years. However, with the

adoption of single cross hybrid technology in 1960s the USA productivity has gone from mere 3.5t/

ha (1960) to 9.68t/ha in (2008).



Fig.4. Impact of Single cross hybrid Maize in India.

Parallel to USA in India the productivity stagnated under 1 t/ha for many decades. However, SCH

technology impact is witnessed today. The present growth rate of area (2.6%), production (6.4%)

and productivity (3.6%) of maize is among the highest in cereal food crops of India. By hardly

covering 20% of maize area under single cross hybrid the productivity of maize has increased by

425kg/ha (2007-2008) this increase in a single year is a landmark in Indian maize scenario (Fig.4).

By covering 100% area under single cross hybrid the production and productivity can be doubled

within no time. Therefore development of single cross hybrids and their adoption in farmers’ field

should become the min strategy to ensure food and feed security of the developing World because

of the following advantages the single cross hybrid technology possess

Advantages of Single Cross Hybrids

Ø Highest yield potential among cereals as per day productivity is more than many crops

Ø Being C4 Plant has better adaptation under climate change as mild increase temperature

in winter favors maize

Ø Tolerant to biotic and abiotic stresses and decreases the vulnerability to recurrent droughts

and climate change

Ø Tolerant to Water stress due to better root system and decreases need for irrigation water

Ø Nutrient responsive (low/high) due to profuse root system



Ø Less yield reduction under nutrient stress condition

Ø Quick and higher percentage of germination

Ø Faster growth and most uniform

Ø Being heterotic escape mechanism works

Ø Crop diversification

Ø Low cost of production

Ø Export potential

Ø Food, income and nutritional security for resource-poor farm families

More than 3 dozen single cross hybrids of normal, QPM and specialty corn from public and private

have been released and are under cultivation in farmers’ fields (Annexure I). Under changing

climatic scenario adoption of SCH technology in maize is most profitable as compared to rice and

wheat due to scarcity of water and increase in temperature. Since, maize requires less water it is

favoured over Rabi rice and also slight increase in temperature during winter favours it over wheat,

as latter suffers due to terminal heat stress.

MAIZE RESEARCH NETWORK IN INDIA

Organized research on maize improvement started in 1957 under the auspices of the All India

Coordinated Research Project on Maize (AICRP on maize) and this was the first in a series of

coordinated projects under the ICAR system. The project has been located at the Pusa Campus,

New Delhi and was upgraded into Directorate of Maize Research in January 1994 with mandate to

organize, conduct, coordinate and generate technology for continuous enhancement in productivity

and production for meeting the ever increasing demand of human food, animal feed and industrial

utilization for starch, oil, and other value-added products. The directorate is entrusted with the

overall responsibility of research, coordination and management of the multidisciplinary

programmes at national level and maintaining linkages with International programmes on maize

improvement as well. DMR has a Regional Maize Research Centre at Begusarai, Bihar and winter

nursery centre at Hyderabad (Fig. 5.).

All India Coordinated Research Project (AICRP) on Maize:

There are 22 centres of AICRP on maize clubbed into to five zones (Table.1.) based on agro ecological

systems of crop cultivation. Research on various aspects of Maize has been conducted during

Kharif , Rabi, Spring and Summer seasons based on the zonal requirements.

Zone I consisted of hilly areas of mainly Himachal Pradesh (Kangra and Bajura), Jammu and Kashmir

(Jammu-Udhampur, Srinagar-Poonch), Uttarakhand (Almora) and North Eastern States ( Barapani



and Jorhat). Zone II consists of North West Indian plains of Punjab (Ludhiana), Haryana (Karnal),

Delhi, Western Uttar Pradesh (Kanpur) and Uttarakhand (Pantnagar).

Zone III included of Northern and Eastern part of India of Bihar (Dholi), Jharkhand (Ranchi), Orissa

(Bhuvaneshwar), Eastern Uttar Pradesh (Varanasi and Behraich) and West Bengal (Midinapur).

Zone IV consisted of Deccan plateau and Southern India of Andhra Pradesh (Hyderabad and

Karimnagar), Tamil Nadu (Coimbatore and Vagarai), Karnataka (Arbhavi and Mandya) and

Maharashtra (Kolhapur). Zone V included of Central and Western India of Madhya Pradesh

(Chindwara and Jhabuva), Chhattisgarh (Ambikapur), Gujarat (Godhra) and Rajasthan (Udaipur

and Banswara).

Fig.5. Maize Research Net Work in India



Table 1. Zones in AICRIP on Maize

State Centres

Zone I Himachal Pradesh CSK HPKV: Kangra, Bajaura

Jammu & Kashmir SKUAS&T (J) Jammu- Udhampur

SKUAS&T (K) Srinagar- Poonch

Uttarakhand VPKAS, Almora

North Eastern States ICAR Research Complex for NEH Regoin

Barapani; AAU, Jorhat

Zone II Punjab PAU, Ludhiana

Haryana CCS HAU, Karnal

Delhi DMR, IARI, Delhi

Western Uttar Pradesh CSAU & T, Kanpur

Uttarakhand GBPUA&T, Pantnagar

Zone III Bihar RRS & SPC, Begusarai; RAU, Dholi

Jharkhand BAU, Ranchi

Orissa Bhubaneswar

Eastern Uttar Pradesh BHU, Varnashi; NDUA &T, Behraich

West Bengal BCKV, Midinapur

Zone IV Karnataka UAS, Bangalore: Mandya; UAS Dharwad: Arbhavi

Andhra Pradesh WNC, DMR, ANGRAU: Hyderabad, Karimnagar

Tamil Nadu TNAU: Coimbatore, Vagarai

Maharashtra MPKV, Kolhapur

Zone V Rajasthan MPUA&T: Udaipur, Banswara

Gujarat AAU, Godhra

Madhya Pradesh JNKVV: Chindwara, RVSKVV, Jhabuva

Chhatisgarh IGVK, Ambikapur

INBRED – HYBRID TECHNOLOGY

HISTORICAL PERSPECTIVES

Ø 1908- G. H. Shull : Inbrd lines of maize showed general deterioration of yield and vigor, but

those hybrids between two inbred higher yield, vigor and uniform performance. He coined

the term heterosis of the condition of performance of hybrids better than their both parents.

Ø 1909- E. M. East: developed the world first hybrid maizes Female inbred line Leaming at

Connecticut, USA. he corroborated the result of Shull



Ø 1920- D. F. Jones proposed a new method of hybrid production of performing four way

cross or double cross. Jones suggested to East a procedure that would make hybrid corn a

reality for industry and farmers, using the already developed Leaming lines as female

parent and Burr’s White as male line.

Ø Testing of a large number of four way cross was tremendous job, since there were six

possible single cross among four inbreds used to produce a double cross.

Ø M. T. Jenkins suggested a prediction of yield of double cross by the average performance

of non parental single cross. It saved the testing and expenses of testing the double cross

lines.

Ø 1924- H. A. Wallace: with his greater contribution, first commercial sale of hybrid seed

started. The first pioneer hybrid for sale was ‘Copper Cross’ which had East’s Leaming

lines on the female side.

Ø 1974-W.A. Russel growing (preserved hybrid seed produced during 1930-70) them under

same environment. He found that uniform increase in yield from the newer strains and > 60

% of yield increase. This phenomenon is based on genetic performance of the hybrid.

Ø 1977-D.N.Duvick: he corroborated the results of Russel

Ø A.R.Hallauer: Significanty contributed in the field of Quantitative genetics for inbred

development in Maize

Fig.6. Pioneers of Inbred-hybrid technology in Maize



Ø Hand detasseling: Initially Single cross hybrid production technology is full based on

detasseling of three female lines and use of one tassel intact male lines.

Ø 1970- Cytoplasmic male sterile lines of Texas (cms-T) almost cover 85% of US corn belt.

Simulatenously cms-T became suspectibel to Helminthosporium maydis. US suuferred >80%

corn production during this year. It reverted to hand detasseling practice again.

Ø S.K.Vasal: awarded World Food Prize for the contribution of QPM hybrids for achieving the

food and nutritional security

Ø 1990-2000 USA Corn Belt covered with 100% Single Cross Hybrid Maize technology.

STRATEGIES FOR THE DEVELOPMENT OF INBREDS

1. Short term strategy: Inbreeding in best single cross hybrids or Pedigree selection (Flow chart.1.)

Flowchart.1. Short term strategies of inbred development



2. Long term strategy: Developing synthetic/ gene pool from the high per se and GCA (General

Combining Ability) inbred lines for the extraction of productive inbred lines (Flow chart.2.)

Flowchart.2. Long term strategies of inbred development

ISOLATION DISTANCE

PROPER ISOLATION DISTANCE

Out crossing

Managing pollen drift in maize has received considerable attention in recent years largely as the

result of the development and adoption of new seed technologies. Various practices viz., spatial

and temporal are used to control pollination in maize fields.

Proper isolation distance

Proper isolation is accomplished in three ways including: a) distance b) time and c) good

synchronization. Seed producers often say that the best isolation is a perfect nick, that is, when

the pollen parent starts shedding just before silk emergence in the female parent. An additional

option may be used when it is difficult to get suitable distance or time isolation. This includes

planting a barrier of foundation or certified seed of the same variety on all sides about 50 m from

the production block.

v Depends upon wind velocity/ season



v Minimum isolation distance required for

Ø Inbreds - 500m

Ø Hybrids – 400m

§ Select area/seasons where maize is not commercially cultivated to out crossing

§ Through seed village concept- one Inbred/ Single cross hybrid seed production in one

village

Seed Village Concept for maintaining the genetic purity

Ø Solves the isolation problem

Ø Maintaining genetic purity

Ø Easy monitoring

Ø Reduces the maintenance cost

Ø Reduces the cost of transportation

Ø Reduces the cost of hybrid seed

Ø Ensures availability of seed in time

Ø Solves the storage problem

Why to maintain plant population?

Optimum plant population to be maintained for realizing maximum yield

• Thinning after 10 days of germination to maintain proper plant population

• To avoid variation with respect to

§ Plant height

§ Cob length

§ Test weight

§ Maturity

Maintaining High level of yield in Inbred

Ø High level of genetic uniformity requires (minimum roguing)

Ø Technology (Package practice)

Ø Appropriate season for sowing(Stress free season), maize being sensitive to drought and

water logging

Ø Maize is highly sensitive to brackish soil and water

Ø Proper site selection for better monitoring

Ø Fertile land – Sandy loam to Loamy soils

Ø Good quality of irrigation water and drainage

Ø Follow the Integrated Pest Management (IPM)/ Integrated Disease Management (IDM)/

Integrated Nutrient Management(INM)/ Integrated Weed Management (IWM)



SEED INCREASE

Only off- type plants should be removed to minimize inbreeding depression. The number of

plants to be used to advance generation is dependent on two factors: the number of plants required

adequately representing the genotype and the quantity of the seed required to meet the future

seed requirement. Mild selection during seed production and multiplication are inevitable. However,

they should be minimized. Purity maintenance is normally done in isolation.

SEED MULTIPLICATION RATE

Parental seeds are multiplied by four stage of seed chain (Fig.7a & 7b)

Nucleus Seed

Breeder Seed

Foundation Seed

Certified Seed

Ø Breeder Seed and Foundation Seed should never used for commercial hybrid seed

production.

Fig.7a. Area and Production of Different Seed classes under Seed Chain

â

â

â



INBRED LINE SEED PRODUCTION AND MAINTENANCE

Nucleus Seed

Ø First phase in seed multiplication programme

Ø Seeds of selected basic stocks are planted in isolation

Ø Ear to Row planting

Ø Selfing

Ø Contaminated Ears are reomoved

Ø Uniform Ears are bulked from Basic stocks

Breeder Seed

Ø Second phase in seed multiplication programme

Ø Nucleus seeds are used for production of breeder seeds

Ø Seeds are planted in isolation


Ø Selfing

Ø Contaminated Ears are removed

Ø Uniform Ears are bulked

Ø Seed multiplication followed under strict observation of concern breeder only

Fig.7b. Area and Production of Different Seed classes under Seed Chain



Foundation Seed

Ø Third phase in seed multiplication programme

Ø Breeder seeds are used for the multiplication of Foundation seed

Ø Planted in isolation


Ø Selfing

Ø Contaminated Ears are reomoved


Ø Seed multiplication done by recognized seed producing agencies in public and private

sector under the strict supervision of Seed Certification Agency

Certified Seed

Ø Fourth and Final phase in seed multiplication programme

Ø Foundation seeds are used for multiplication of Certified seeds


Ø Selfing

Ø Contaminated Ears are removed


Ø Seed multiplication done by registered seed growers under the strict supervision of Seed

Certification Agencies of concerned states

Commercial hybrid seed production

Ø Certified seeds of Parental inbreds are planted in appropriate Male : Female ratio for

hybrid seed production

Steps involved in maintenance of Genetic purity of Maize inbreds:

A strategy has been worked out based on ear to row evaluation and selfing of desirable and

uniform ears for maintaining the genetic purity in inbred lines. The selected ears of the inbred

lines are planted in a 2m row of 18-25m/ bed separated by 50cm each. This planting method has

been found to be an efficient, easy, quick and result –oriented method and facilitate the evaluation

of ears and roguing of off-types between and within rows. The ears are evaluated for uniformity

and only those ears (of an inbred) are retained that show 100% uniformity and the balance self

seed of such ears is bulked and grown in isolation for seed increase (Flow Chart 3). The balance

self seed of contaminated ears is removed from the lot. Based on the distinct and diagnostic

traits, off-types, late germinated, weak, diseased, insect/ pest- infested and other undesirable

types are rogued- off at appropriate growth stages, viz., 15-20 days after sowing (based on seedling



traits), at knee high (based on leaf and stem traits ),before and at flowering (before anthesis,

based on tassel and ear traits) . This approach has been found to be helpful in maintaining genetic

purity of inbred lines as well as longevity of single cross hybrids of maize.

Flow Chart 3: Steps involved in maintenance of Genetic purity of Maize inbreds

CROP MANAGEMENT PRACTICES

Ø Selection of field: Easily accessible, Sandy loam to Loamy soils, Good drainage and

irrigation facility

Ø Proper season : Rabi season is risk-free season for seed production being disease –

free, insect-pest –free, temperature in comfortable range

Ø Irrigation schedule is as per the package of practice

Fertilizer application

The available quantity of the farmyard manure should be incorporated into the field before

sowing. A combination of organic manure and chemical fertilizer is known to give better yield. A

balanced application of 120-150kg N, 60-75 kg P,60-75kg K per hectare and 25 kg Zinc sulphate /



ha is recommended.10% of total quantity of nitrogen and the entire quantity of phosperous,

potash and zinc should be applied in bands 5-7 cm deep before sowing. The rest of the nitrogen

should be applied in four doses as mentioned below as top dressing .

Plant stage 4 leaf 6-8 leaf flowering Grain filling

Quantity 20% 30% 30% 10%

ROGUING

Ø Based on distinct and diagnostic characters furnished by breeders, remove off-type

plants

Ø Remove diseased, late and weak plants

1st roguing- At 15 to 20 days of crop (Figs.8 & 9)

• Remove vigorous plants from inbreds

• Remove other undesirable plants——late germinated, diseased, insect-pest affected,

• Remove plants with variable leaf traits

2nd roguing - Before flowering (Fig.10)

• Remove plants with variable stem colour

• Remove weak plants, diseased

3rd rouging- At flowering before anthesis (Fig.11)

• Remove late plants

• Remove plants with variable height

• Remove plants with variable tassel and husk traits

IMPORTANCE OF THE DIAGNOSTIC TRAITS

Lack of proper characterization of parental lines can be the cause of serious losses in seed

production. As maize inbred lines typically have a large Genotype x Environment (G x E) interaction

compared to other crops, it is essential to obtain sufficient performance information on inbreds in

their planned production environments. Of special importance is to obtain information on leaf

traits, attitude of plant growth, floral traits like silk emergence, anthesis, color of anthers, color of

silk, floral synchronization (nicking), seed yields in female lines, pollen production capability of

male lines, and responses of inbreds to fertility, pests, diseases, and pesticides. After harvest

parameters like cob length, kernel arrangement, cob size, color of kernels and kernel type should



Fig.9. Removal of late germinated / vigorous plants

Pest infested – Dead heart Diseased plant

Fig.8. Roguing of pest and disease infested plants



Fig.10. Maintenance of uniform Inbred blocks

Fig.11. Uniformity of Inbred blocks



be observed critically. The lines showing any deviation from the diagnostic traits must be rogued

out or removed at appropriate stages of crop growth. Verifying of these diagnostic traits (Table.2)

continues at all stages of seed production as mentioned below:

Given below is the list of traits which have to be recorded in respect of each parental line as

well as the hybrids.

Leaf traits: to be recorded at stages 61, 71 and 75, respectively.The off-types must be rogued out

as shown in Fig.12.Different leaf traits and their expression are summarized as under:

Ø Angle: small, wide

Ø Attitude of blade: straight, drooping

Ø Width of blade:narrow, medium, broad

Ø Anthocyanin coloration of sheath: present, absent

Fig.12. Leaf traits

Table.2. Verifying diagnostic traits at different stages of seed production

Stage code General description Stage code General description

61 Beginning of anthesis 85 Soft dough

65 Anthesis halfway 92 Caryopsis hard (can no longer

be dented by thumbnail)

71 Caryopsis watery ripe 93 Caryopsis loosening

75 Medium milk



Tassel traits: to be recorded at stage 65.The off-types must be rogued out as shown (Fig. 14 & 15).

Different tassel traits and their expression are summarized as under:

Ø Anthocyanin coloration at base of glume : present, absent

Ø Anthocyanin coloration of glumes excluding base present, absent

Ø Anthocyanin coloration of anthers :present, absent

Ø Density of spikelets: sparse, dense

Ø Time of anthesis : very-early, early, medium, late

Ø Angle between main axis and lateral branches :Narrow, Wide

Ø Attitude of lateral branches:straight, curved, strongly curved

Ear traits: to be recorded at stages 65, 92 and 93. The off-types must be rogued out as shown in

Fig.16 & 17. .Different ear traits and their expression are summarized as under:

Ø Anthocyanin coloration: present, absent

Ø Length without husk: short, medium, long

Ø Diameter without husk: small, medium, large

Ø Shape : conical, cylindrical

Plant height: inbred and hybrid: The trait plant height is to be recorded at stage 75.The off-

types have to be removed at the appropriate stages. The inbreds and the hybrids are

characterized as per the category given below (Fig13):

Fig.13. Plant length



Fig.14. Tassel traits

Fig.15. Tassel traits



Fig.17. Ear traits

Fig.16. Ear traits



Fig.18.Kernel traits

Fig.19. Kernel traits

Ø No. of rows of grains :few, medium, many

Ø Time of silk emergence:very early, early, medium,late

Ø Anthocyanin coloration of glumes of cob:present, absent

Kernel traits: to be recorded at stages 92 and 93, respectively. The off-types must be rogued out

as shown in Fig. 18 & 19. Different kernel traits and their expression are summarized as under:

Ø Row arrangement: straight, irregular

Ø Poppiness : absent, present

Ø Sweetness : absent, present



Ø Waxiness: absent, present

Ø Opaqueness : absent, present

Ø 1000 weight : small, medium, large

Ø Grain type: flint ,semi-flint, dent

SINGLE CROSS HYBRID (SCH) SEED PRODUCTION:

Crossing between two desirable inbreds as a male and female parents and deriving F1 or hybrid

from the cross is called as Single Cross Hybrid (Fig.20). Commercial hybrid maize seed producers

employ various practices to control maize pollination including crop rotation to minimize volunteer

maize plants and reduce the need for roguing; selection of parent seed of high purity; vigorous

roguing of both male and female rows to insure only the desired parents remain; aggressive

detasseling of the female parent to prevent self pollination; temporal isolation of the silking period

so as not to coincide with corn in nearby fields; planting of pollen parent border rows around the

seed production field to insure that the field is flooded with the appropriate pollen and to dilute

adventious pollen; and adequate isolation distance to insure acceptable levels of protection from

adventious pollen. Based on the descriptors, the inbred lines are categorized as female (Fig.21)

and/or male (Fig.22).Good field management of maize seed production requires giving attention

to adequate site selection including isolation, use of the best agronomic management practices,

appropriate female : male ratios, achieving a good nick between parental lines, properly controlling

pollen production in female rows through detasseling, effectively removing off-type plants, and

harvesting the crop in a timely fashion(Flow chart .4).

CRETERIA FOR SEED SETTING

Ø Male should be taller than female

Ø Longer duration of pollen shedding

Ø Irrigation during dry spells to prolong pollen shedding

Ø Nutrient + Irrigation together for

− Increases pollen production

− Pollination

− Increased seed setting

SYNCHRONIZATION OF MALE, FEMALE FLOWERING

Ø Staggered planting

Ø Manipulation in plant distance: Wider/narrow spacing planting

Ø Irrigation along with fertilizer application

Ø Application of FYM in either male or female to induce earliness and vigor

Ø Chemicals: Growth regulators



Fig.20. Single Cross hybrid Seed production system

Flowchart.4. Maintenance and seed production programme (ear-to-row method)



Fig.21.Characteristics of Good seed parent

Fig.22.Characteristics of Good pollen parent



Fig.23. Seed production Layout



Fig.24. Seed Production- North India

Fig.25. Seed Production- South India



CROP PROTECTION

DISEASE MANAGEMENT -Major diseases and their management

1. Turcicum Leaf Blight (TLB)

o Spray with Zineb/Maneb @ 2.5-4.0g/l at 8-10 days interval

2. Polysora Rust:

o Fungicide applications, should start when pustules first appears on the leaves

o Three sprays of Dithane M-45 @2-2.5g/l of water beginning from first appearance of

symptoms at 15 days interval can minimize the disease.

3. Banded leaf and sheath Blight (BLSB)

o Stripping of 2 lower leaves along with leaf sheath

o Foliar spray of Sheethmar( Validamycin) 2.7ml/l of water

o Foliar spray (30-40 days old crop) of Rhizolex 50 WP @ 10g/10 l of water

o Seed treatment of peat based formulation @13g/kg of Pseudomonas fluorescence or as

soil application @7g/l of water.

4. Post Flowering Stalk Rots of Maize (PFSR)

o Use crop rotation

o Avoiding water stress at flowering and balance soil fertility specially increases the potash

level up to 80kg/ha helps in minimizing the diseases

o Use of biocontrol agents Trichoderma Formulations in furrows after mixing with FYM @10g/

kg FYM (1kg/100 Kg FYM/acre) 10 days before its use in the field in moist condition.

5. Downy Mildews

o Rogue and destroy infected plants

o Planting before rainy season begins, can minimize the occurrence of diseases.

o Seed treatment with metalaxyl fungicided i.e. Ridomil 25 WP, Apron 35 SD, Apron 35 FN etc

@ 2.5 g/kg seed.

INSECT PEST MANAGEMENT- Major pests and their management

1. Chilo partellus

o Stem borer. Chilo partellus is a major pest of kharif throughout the country

o Spray 0.1% Endosulfan at after 10 days of germination (DAG) (700 ml Endosulfan 35 EC in

250 litre water)



2. Shoot fly

o To avoid the pest damage, sowing must be completed before first week of February.

o Treat seed with 5ml/kg seed with Imidacloprid

3. Termite

o Clean cultivation delays termite attacks

o Apply Fipronil granule followed by light irrigation. The application should be at the site

of infestation.

Harvesting

Harvesting may begin as early as when developing kernels approach physiological maturity. Maize

seed is commonly harvested with 15 to 25% moisture content. The male and female lines must be

harvested separately to avoid mechanical mixture of seeds. Harvesting fully mature seed will

result in maximum yield, improved appearance of seed, better seedling vigor in the subsequent

crop, greater resistance to mechanical injury while handling in the conditioning plant, and reduced

susceptibility to injury from high drying temperatures.

Mechanical admixtures

Maintaining genetic purity of a line is very tedious and lot of care should be taken for avoiding the

mechanical admixtures especially in threshers and harvesters. Chances of mixing one genotype

with other will be very high in case of mechanical handling of all harvest and post harvest operations.

Before using any equipment, first make sure of it is free from any kind of biological and non-

biological admixture.

Post-harvest operations

Once the crop has been harvested it must be transported to the processing facility where it is de-

husked, dried, sorted, cleaned, sized, treated, and packaged. Storage and then marketing and sale

of the product follow. This long chain of activities requires intensive management, meticulous

planning, and impeccable timing, a high level of technical expertise, and the cooperation of weather

and other factors.

STAGES OF CROP INSPECTION

1. At the time of sowing

Purpose: Land, isolation distance, proper sowing time

2. During pre-flowering/vegetative stage

Purpose: Verify the roguing and removal of off type plants



3. During flowering stage

Purpose: To check disease and pest infestation and variable tassel/ ear husk traits

4. During post-flowering and pre-harvest stage

Purpose: To remove the late plants

5. Harvesting time inspection

Purpose: To decide the proper time of harvesting

6. Post Harvesting

Purpose: To check the dissimilar cobs in inbreds, remove the diseased and pest infested

cobs

Problems of continuous seed production at Specific Locations

Ø Migration of new pests and diseases

Ø Increasing inoculums of pests and diseases



Ø Restrict the acclimatization of lines

Ø Reduce the life of inbreds/parents of hybrids

Ø Threatening the stability of hybrid parents

MINIMUM SEED STANDARDS IN MAIZE

Table. 3. Minimum Seed Standards in Maize

QUALITY ASSURANCE

Seed production is always dependent on quality assurance (QA). Quality assurance begins in the

field with field inspection. Initial field inspection must verify.

• Was the field sown with an approved seed lot?

• Whether Field meets the prospected land requirement and to the previous crop

• Is it in compliance with prescribed isolation standard and number of border rows?

• Proper rouging for the removal of contaminating factors

• Proper harvesting to avoid mechanical admixtures

• Compliance of recommended package of practices



GERMPLASM EXCHANGE

Exchange of Germplasms and Inter-Institutional Hybrid Breeding Program

Each centre has developed their own hybrids in all categories of Normal Single Cross Hybrids,

QPM Single Cross Hybrids, Sweetcorn Single Cross Hybrids and Popcorn Single Cross Hybrids. To

evaluate their performance across the country, these hybrids are specially evaluated within their

zonal centres called as Zonal trials. From that outstanding hybrids are promoted to check their

performance across the country. These selected hybrids have been distributed all other centres of

different zone in the name of Inter Institutional Single Cross Hybrids. Best hybrids have been

selected and they have been included in the AICRIP Programme for proper release.

The distribution of germplasm to users can be regarded as an ultimate goal of germplasm bank

operations, especially as it is the step that links conservation and utilization. Similarly, it is important

to the gene bank that new germplasm is received through collecting missions or, to avoid duplication,

through exchange programmes with other gene banks. This is the main source of increasing the

desirable breeding material and disseminating the best quality material across the world.

Benefits of Germplasm exchange

• Continuous development of new products (new maize varieties) for resistance to biotic

and abiotic stresses

• Information Exchange among maize breeders

• Germplasm catalogue: This will entail a published cataloguing of genetic materials present

in each country to enable breeders to have knowledge of elite germplasm present in the

region. In each country there will be a catalogue of released materials and their

characteristics.

• Germplasm Access and Exchange; which will have to operate in the context of an

appropriate framework. The framework will outline logistics to access and exchange

germplasm from another country.

• Enhancing the accessibility of new varieties to farmers through a collaborative effort of

Breeder Seed Production

• Fingerprinting of breeders lines

• Enhancing resistance to maize streak disease in the region by a collaborative effort of

conventional and molecular breeding



PUBLIC-PRIVATE SECTOR PARTNERSHIPS (PPP)

The network will encourage public-private sector collaboration through joint collaborative activities

and information on new hybrids available in participating partner. The network meetings will be

forums for muting regional expansion and operation of seed companies across countries. Whenever

a seed companies identify a need and would like the breeders to address that specific need then

the network will target their research to meet the desired product. If seed companies want to

initiate new operations in another country, the forum would assist to give information on

opportunities for variety marketing in another country.

Seed Production through PPP mode

Several meeting and brainstorming had been conducted to establish a common protocol for active

participation of PPP in maize single cross hybrids. Classical example is of Green Gold; a Maharashtra

based private seed company singed Memorandum of Understanding (MOU) with CCS HAU, Hisar

for using their public bred hybrids of HQPM 1(QPM Single Cross hybrid) and HM 4(Baby corn

Single Cross Hybrid).

Strengthening characterization, evaluation and the enhancement of Germplasm

While germplasm collecting and preservation should continue, in the near future the emphasis

should be shifted to characterization and evaluation, and in-depth research into germplasm

resources. Biotechnology, including the use of molecular markers, cell engineering and genetic

engineering, should be used in germplasm enhancement and more genotyping should be

conducted. In particular, favorable genes existing in wild relatives of crops should be transferred

to cultivars to obtain new types of germplasm. Germplasm researchers should provide not only

elite germplasm but also information concerning its characteristics and genetic mechanism in

order to improve the use of the material.

Germplasm enhancement should target diverse ecological regions and diverse breeding objectives.

For wild relatives especially, more trials and research is needed in order to exploit potential value.

Germplasm researchers should understand the unique advantages and the accompanying

disadvantages of the accessions, and form clear objectives to improve them.

Promoting the exchange of Germplasm and associated information

Germplasm researchers should increase and improve their contacts with breeders to exchange

germplasm and associated information. To do this, various activities need to be organized such as

eco geographical trials. These should include material from different ecological regions and provide

opportunities for interaction between germplasm researchers and users as well as farmers.



Formulating benefit-sharing policies

Benefit-sharing policies for the use of germplasm should be drawn up in order to encourage

cooperation between germplasm holders and users. On one hand, this should include the principle

that germplasm providers would benefit from the use of their germplasm by breeders and other

researchers, while on the other hand, encourage breeders to send their improved and enhanced

elite materials to gene banks for preservation, exchange and use.

Strengthening financial support

Conservation efforts and use of germplasm resources must be strengthened. At the same time,

each institution concerned with germplasm should must be provided funds, through the various

channels available, to carry out research to identify, evaluate, enhance and ensure the provision

of useful germplasm for crop improvement and other purposes.

Establishing a national coordinating mechanism

A national coordinating mechanism is essential for the promotion of the use of plant genetic

resources and a national committee for plant genetic resources should be the coordinating and

decision-making body in the country, composed of officials from various sectors, as well as experts

on conservation and the use of plant genetic resources. This body would be responsible for

formulating rules and management policies, and for making short- medium- and long-term plans

for action.

POPULARIZATION OF SCH SEED PRODUCTION

(Joint effort of DMR, ICAR (Extension Division) and KVKs)

Three partners viz., DMR, ICAR (Extension Department) and KVK of North Eastern states (Fig 26)

together to popularize the Single Cross Hybrid Maize technology in extensive way. The directorate

provided technical advice and inputs to the KVKs of the country through ICAR Extension division.

Under this joint effort, each KVK has been classified to produce Single cross hybrids and multiply

different male and female inbred lines to be distributed to the farmers of all KVK jurisdictions for

cultivation. Adequate training also has been imparted to the farmers by these KVKs by means of

Front Line Demonstrations (FLD) and other methods. Under this venture the farmers have been

benefited by means of strengthening their economy and nutritional security.

SEED VILLAGE CONCEPT

Seed village concept has been actively implemented in Midnapur district of West Bengal. Under

this concept space isolation has been achieved by means of planting single parent in a single



POPULARIZATION OF SCH SEED PRODUCTION

(Joint effort of DMR, ICAR (Extension Division) and KVKs)

Fig.26. Hybrid Seed Production in North East states



Fig.27. Increasing trend of Hybrid seed production in West Bengal

village. By this approach, maintenance of purity of the inbreds has been achieved and single cross

hybrids seed production also increased. Area under HQPM 1 hybrid increased tremendously (Fig.

27) after implementation and eventually it replaced water demanding paddy crop with maize and

ensured higher remuneration than Paddy cultivation.

SINGLE CROSS HYBRIDS OF SPECIALTY CORN

Incase of specialty corns viz., sweet corn and pop corn, so far only varieties are available in India.

These varieties don’t fetch premium price in the market because of heterogenous nature, non

uniformity in yield, sweetness and popiness, respectively. However, demand for such corns is

increasing day by day. These specialty corns are getting significance in peri-urban agriculture.

Keeping this in view, public institutions are actively engaged in breeding of single cross hybrids of

sweet corn and pop corn. HM 4 is a single cross hybrid baby corn has been released by CCS HAU,

Karnal centre in 2005 (Annex. I). HM 4 hybrid seed production is taken up by Green Gold; a

Maharashtra based seed company in signing memorandum of understanding with CCS HAU, Hisar

under PPP mode. Given below are the Public bred single cross hybrids of specialty corn ready for

release on framers field.



Technologies ready to be delivered

Sweet corn hybrid HSC 1 has been developed and may be released in near future.HSC 1 (HKI SCST

-1 × HKI 1833) performed better than standard check Win Orange Sweet Corn (yield superiority of

40.13%) and Bajaura SC (yield superiority of 42.07%). HSC 1 has brix value of 29% in compare to

the checks.

In case of Pop corn, two single cross hybrids viz., DMR PC 1 × HKI PC 5-2 and HKI PC 5-1 × Win Pop

43-2 performed better than the standard check Ambar pop corn in terms of yield superiority of

28.8% and 17.1% respectively.

SUMMARY

Production of hybrid maize seed is a unique and dynamic industry worldwide. The foundation of

the industry is productive inbred lines which are developed by research programs which must

invest significant quantities of time and resources. These lines are then used in field production to

produce hybrid seed. This is followed by proper conditioning and marketing of the seed. Many

steps are involved in the production, processing, and marketing chain. Good field management of

hybrid maize seed production requires giving attention to adequate site selection including isolation,

use of the best agronomic management practices, using appropriate female : male ratios, achieving

a good nick between parental lines, properly controlling pollen production in female rows through

detasseling or other means, effectively removing off-type plants, and harvesting the crop in a

timely fashion. This work is often done under contract with private farmers, thus the selection,

training, and collaboration with the best farmers is essential. Once the seed crop has been

harvested it must be transported to the processing facility where it is de-husked, dried, sorted,

cleaned, sized, treated, and packaged. Storage and then marketing and sale of the product follow.

This long chain of activities requires intensive management, meticulous planning, and impeccable

timing, a high level of technical expertise, and the cooperation of weather and other factors. An

effective quality control program should monitor and help coordinate all aspects of the maize

seed program.



ANNEXURE

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LIST OF PUBLIC-BRED SINGLE CROSS HYBRIDS OF MAIZE DEVELOPED AND RELEASED FOR CULTIVATION IN INDIA DURING 2000-2010

S.No Name Pedigree Centre Year of Area of adoption Characteristics

release

NORMAL MAIZE

1 HM 11 HKI-1128 X HKI-163 CCS HAU, Karnal 2009 Across the country Late maturity, orange, flint,

except Himalayan belt Responsive to higher doses of

(rabi) fertilizers, avg. yield 55 q/ha

3 DHM-111 BML 6 X BML 15 ANGRAU, 2009 Andhra Pradesh Medium maturity, Yellow,

Hyderabad semi-dent, Nutrient

responsive, tolerance to

lodging & stay green,

avg. yield 65 q/ha

4 DHM-113 BML 2 X BML 7 ANGRAU, 2009 Andhra Pradesh Late,orange,

Hyderabad semi-dent, Nutrient responsive

& tolerance to lodging,

avg.yield 66 q/ha

5 DHM-117 BML 6 X BML 7 ANGRAU, 2009 Andhra Pradesh Medium,orange-yellow, flint,

Hyderabad Nutrient responsive, tolerance to

lodging & stay green,avg.yield

75q/ha

6 HM10 HKI 193-2 X HKI 1128 CCS HAU, pKarnal 2008 Delhi, Punjab, Haryana Medium maturity,

and Western Uttar yellow, semi flint, highly

Pradesh,Rajasthan, responsive to inputs,

Madhya Pradesh, resistance MLB & avg yield

Gujrat, Andhra Pradesh, 72 q/ha

Tamil Nadu, Maharashtra

and Karnataka,

Annexure.I

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and Western Uttar resposive to inputs & avg yield

Pradesh 75 q/ha

8 Nithya SKV-50 X NAI-105 UAS, Naganahalli 2008 Karnataka (Kharif & rabi) Late maturity,yellow-orange,

Shree semi-dent, resistant to lodging

& avg yield 80-90 q/ha

9 Vivek V 372 X CM 212 VPKAS, Almora 2008 Jammu & Kashmir Early maturity, yellow, dent

hybrid 33 and Uttarakhand

10 Vivek 23 V 351 X V 341 VPKAS, Almora 2007 Hills of Uttaranchal Early maturity, yellow, flint,

bold, moderate tolerance against

TLB, tall & avg yield 45-50 q/ha.

11 Maize LM 15 X CML 32 PAU, Ludhiana 2007 Punjab, Haryana, Delhi. Early maturity, resistance to MLB,

PAU 352 BSDM, ESR & avg yield 35-48 q/ha

12 HM 8 HKI 1105 X HKI 161 CCS HAU,Karnal 2007 Andhra Pradesh, Medium maturity, orange, flint & avg

Tamil Nadu,, Maharastra, yield 50-68 q/ha

Karnataka

13 HM 9 HKI 1105 X HKI1128 CCS HAU, Karnal 2007 Bihar, Jharkhand, Orissa Medium maturity, orange,

flint & avg yield 60 q/ha

14 Malviya HUZM 185 X HKI1105 BHU, Varanasi 2007 East UP, Bihar, Jharkhand, Medium maturity , yellow, semi flint,

Makka 2 Chattisgarh, West Bengal, responsive to higher doses of

Orissa fertilizers, resistance to MLB & avg

yield 54 q/ha

15 COH(M) 5 UMI 285 X UMI 61 TNAU,Coimbatore 2007 TN under irrigated & Late maturity, semi flint, responsive

rainfed ecology to high inputs, resistance to downy

mildew, moderately resistance to

stem borer, avg yield 42-55q/ha

16 PMH-1 LM 13 X LM 14 PAU, Ludhiana 2007 Irrigated areas of Punjab Late maturity, stem is zig-zag,

resistance MLB, stalk rots, avg

yield 52q/ha

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17 Vivek 21 CM 212 X V 341 VPKAS, Almora 2007 Uttaranchal, HP, J & K Extra early maturity, yellow, semi

and NEH regions, Delhi, flint, bold, , tolerance against TLB &

Punjab, Haryana & avg yield 45-50 q/ha

western UP, Andhra

Pradesh, Tamil Nadu,

Maharastra & Karnataka

18 Vivek 25 V 341 X V 346 VPKAS, Almora 2007 Uttarakhand, HP, J&K Extra-early maturity, yellow, semi

and NEH region dent, bold, tolerance against TLB &

avg yield 50-55 q/ha

19 Vivek 27 V 335 X V 345 VPKAS, Almora 2007 Eastern UP & Bihar, Extra early maturity, yellow, semi-

Jharkhand, Orissa, dent & avg yield 50-55 q/ha

Chattisgarh, & WB &

Maharashtra, AP,

Karnataka & TN

20 PMH-2 LM 15 X LM 16 PAU, Ludhiana 2006 Delhi, Haryana, Central Early maturity, short

& Western UP duration, resistance to MLB, BSDM,

& PFSR

21 Buland LM 11 X LM 12 PAU, Ludhiana 2005 Punjab, UP, Haryana, Late maturity, resistance to TLB,

Delhi, Tarai regions of Common rust, avg yield 85q/ha

Uttranchal.

23 HM 5 HKI 1344 X CCS HAU, Karnal 2005 Haryana Medium maturity, white, dent

HKI 1348-6-2 responsive to high doses of fertilizers,

medium tall, tolerance to frost &

avg yield 68-72q/ha

24 HM 4 HKI 1105 X HKI 323 CCS HAU, Karnal 2005 Haryana Grain purpose: medium maturity,

orange, flint, medium tall,

& avg. yield 60-68 q/ha

25 Vivek CM 152 X CM 212 VPKAS, Almora 2005 J & K (Himalayan region), Extra early maturity with moderate

Hybrid Andhra Pradesh, Tamil degree of tolerance against TLB &

Maize 15 Nadu, Maharastra & avg yield 45-50 q/ha

Karnataka

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26 Vivek CM 153 X CM 212 VPKAS, Almora 2005 Across the country, Extra early maturity with moderate

Hybrid except hill states. degree of tolerance against TLB,

Maize 17 MLB, avg yield 40-50 q/ha

27 Pusa Extra CM 150 X CM 151 IARI, Delhi 2004 J&k, Uttarakhand, NE, Extra early maturity, tolerance to

Early HP, Assam, Haryana, TLB, MLB,ESR & avg yield 45-50 q/ha

Hybrid Punjab, Andhra Pradesh,

Maize 5 Tamil Nadu, Maharastra

& Karnataka

28 Pratap EI-116 X EI-364 MPUAT, Udaipur 2004 Rajasthan, Gujarat, MP Extra early maturity, white,

Hybrid semi flint, moderately resistance to

Maize 1 C.partellus, & average yield of

38 q/ha

29 DMH 2 CI-4 X KDMI 10 UAS, Dharwad 2002 Karnataka Late maturity, yellow, semi flint,

resistance to SDM & tall

30 Vivek CM 214 X CM 145 VPKAS, Almora 2001 AP, Karnataka & TN Extra early maturity ,

Hybrid toleranceagainst TLB, MLB & avg

Maize 9 yield 45-50 q/ha

31 Vivek CM 212 X V 25 VPKAS, Almora 2001 UP Extra-early maturity, yellow,

Hybrid 5 semi flint, bold Maize 5, against leaf

blight & stem borer, average yield

45-50 q/ha

32 Pusa Early CM 213 X CM 142 IARI, Delhi 2001 Punjab, Haryana & Delhi Early maturity, yellow, flint, bold

Hybrid 3 tolerance to high temperature,avg

yield 40-55q/ha

33 JH 3459 CM 143 X CM144 PAU, Ludhiana 2001 Punjab, Haryana, UP Early maturity, orange, flint & avg.

yield 35-40 q/ha

34 Sheetal LM9 X LM10 PAU, Ludhiana 2001 Punjab (rabi) Late

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35 HHM 1 HKI-536 X HKI- 295 CCS HAU, Karnal 2000 Haryana Medium maturity, resistance to MLB,

Common rust, tolerance to major

insect-pests, frost,cold, & avg yield

50-60q/ha.

36 HHM 2 HKIW-1352 X CCS HAU, Karnal 2000 Haryana state under Late maturity,

HKIW-1344 irrigated conditions responsive to fertilizers, resistance to

MLB in kharif & common rust in rabi

tolerance to major insect-pests, tall

& avg yield 50-60 q/ha

QPM

1 HQPM -7 HKI-193-1 X HKI-161 CCS HAU, Karnal 2008 Andhra Pradesh, Late maturity, Yellow, semi-flint,

Tamil Nadu, Karnataka ,

Maharastra Resistance to MLB, avg. yield 72q/ha

2 Vivek VQL 1 X VQL 2 VPKAS, Almora 2008 Jammu & Kashmir and Extra early maturity, yellow, dent,

QPM 9 Uttarakhand, Himachal performed better at low N2 & avg.

Pradesh, Andhra Pradesh, yield 52-58 q/ha

Tamil Nadu, Karnataka,

Maharastra

3 HQPM 5 HKI 163 X HKI 161 CCS HAU, Karnal 2007 Across the country Late maturity, orange, flint,

responsive to higher doses of

fertilizers, resistance to MLB & chilo

partellus & avg yield > 58 q/ha

4 Shaktiman 3 CML 161 X CML 163 RAU, Dholi 2006 Bihar Late maturity, orange-yellow, semi

flint, tall, QPM hybrid with 0.73%

tryptophan in protein, fair tolerance

against MLB, LSM

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i)5 Shaktiman 4 CML 161 X CML 169 RAU, Dholi 2006 Bihar Semi flint, QPM hybrid 0.930

tryptophan in protein, , resistance

against MLB.

6 HQPM 1 HKI 193-1 X HKI 163 CCS HAU, Karnal 2005 J&K, Uttarakhand, Late maturity, yellow, dent,

NE, HP, Assam responsive to higher doses of

fertilizers, tolerance to frost/ cold,

resistance to MLB and common rust

& average yield 62 q/ha

7 Shaktiman 2 CML 176 X CML 186 RAU, Dholi 2004 Bihar Late maturity, tall , resistance

against MLB, QPM hybrid with 1.04%

tryptophan in protein

BABY CORN

1 HM 4 HKI 1105 X HKI 323 CCS HAU, Karnal 2005 Across the country Baby corn: medium maturity, regular

ovule arrangement, light yellow to

cream colour, sweet, 3-4 pincking/

plant, yield - depending upon

duration 6-8 q/ha

Directorate of Maize Research (Indian Council of Agricultural Research)Pusa Campus, New Delhi 110012 (India)Website : www.maizeindia.orgEmail: [email protected]: 011-25841805, 25842372, 25849725Fax: 011-25848195

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