Seed Production Manual of

Maize

Prepared by:Santosh pathak (IAAS, Lamjung)

Introduction Maize occupies second position after rice in Nepal.

It is a main staple food crop of more than 55% of the people of Nepal.

It can be used as cattle feed and fodder also.

Depending upon the altitude it is grown during winter, summer and rainy season.

Although the major area is under rainy season crop and the productivity is higher in

winter season crop.

More than 80% of the maize is grown in hills (70% in mid hill and 10% in high hill)

and about 20% in terai and inner terai region of Nepal.

There were 8,75,428 ha (with production of 19,30,669 tons) in 2008/09, which has

increased to 8,75,660 ha ( with production of 18,55,184 tons) in 2009/10.

Maize covered about 25% area of cereal crop production.

Seed releasing subcommittee of Nepal has recommended total 23 varieties of

improved maize upto 2010, but 7 varieties are denotified.

Climate requirements It is grown in between 50oN to 40oS upto an elevation of 4000 m.

In Nepal, it can be successfully upto 9000ft.

It is suited to warm or hot climates.

It is grown in all seasons in tropical environments. It is grown in temperate region

during the summer season.

Germination and growth are slow in low temperature.

For emergence, it takes 20 days in 17-19oC and 5-6 days in 25oC average.

Broadly the wholemaize area in nepal has been divided into three growing regions on

the basis of altitude such as:

oHigh altitude(Lekh) above 5000 ft

oMid hills 2500-5000 ft

oTerai,Inner terai and lower elevation 2500 ft

Soil requirementsSoil needs to possess sufficient moisture for maize growth and development.

Seeds or seedling suffer from an excess of water or water logging (6-7 hours) in case of

poor drainage.

Maize is a crop of upland or Bari where water does not stagnate.

Well-drained loam or light loamy soils having more organic matter are most suitable

for maize.

It is however grown in all types of soils.

Maize needs a pH range of 5.5-8.

Land requirementsThe selected field of maize should be free from volunteer maize plants and it should be well drained and aerated also. Field standards

i.Field inspection Generally, three inspection phases are practiced in maize. They are:

• Before tasseling In this inspection phase maize plant is properly examine for its sound

vegetative growth obtained by proper inter cultural practices such as fertilization , irrigation etc.

• Tasseling or floweringIn this phase proper moisture and nutrients should be provided and tall plants should be detasseled before shedding.

• Cob examineCob should be examined to avoid any disorder in cob.

After field inspection, lab inspection is done to check:

• Varietal purity • Inert material• Off types and other• Final moisture content before tagging• Germination percent

ii. Isolation requirements Maize is generally cross-pollinated crop and pollinating agent is normally

wind. It should be prevent from foreign pollen contamination. The foundation seed plot should be isolated by a minimum distance of 300m

and certified seed plot by 200 m from plots of other varieties. Time isolation should be provided at least by two weeks between two

maize varieties. iii. Varietal purity

The maximum permissible limit of off type plants that have shed or shedding pollen is 1.0% in foundation and 2.0% in certified seed production plot at any inspection during flowering when 5.0% or more of the plants have receptive silks.

iv. Roguing

Maize being cross-pollinated crop, timely rouging is necessary to maintain varietal purity.

Proper rouging should be done before flowering of seed crop to avoid contamination due to out-crossing.

Roguing of off type plants should be continued throughout flowering period.

Cultural PracticesLand preparationPrepare the land by giving one deep ploughing followed by 2-3 harrowing and leveling to prepare desired tilth. If necessary one pre sowing irrigation should be given before 1st ploughing.

Time of sowing

The time of sowing maize is differing from place to place.

Maize can be sown two weeks before the onset of monsoon where

irrigation facility exists.

It is generally sown from 3rd week of March (in khet land in mid hill) to 1st

week of April in case of rainy season maize (in bari land).

Seed production of maize is successful in terai in winter due to low

isolation problem and less incidence of disease and pest.

Maize can be sown in Oct-Nov in terai. Seed selectionSeed should be selected from the authorized agency with kinds and source approved by seed certification agency.

Method of sowing Spacing:75cm x 25cm row to row and plant-to-plant Sowing depth: 5-6cm. Generally maize is planted in behind the plough in Nepal.

Seed rate 16-20kg/ha is sufficient. overplant by 15-20% to compensate for unfavorable condition. 55-60 thousand plants per ha at harvest would be needed to attain maximum

seed yield.

Fertilizer management Fertilizer recommendation is based on soil analysis value from soil testing lab. Add 10-15 tons of well-rotted organic matter as FYM or compost.

One third N plus full P , K and Zn as basal dose and remaining 1/3rd at knee high stage and another 1/3rd before tasseling.

Fertilizer Recommended dose(kg/ha)

N2 120-150

P2O5 50-60

K2O 40-50

ZnSO4 20-25

Water management Maize is very sensitive to excess water and drought conditions. So irrigate the field frequently and do not let the water stand in field more than

few hours by opening bunds or drainage channel. The most critical stage of maize are:

• Tasseling• Silking• Early grain filling

Intercultural operations

Timely weeding of maize is very important so 2-3 hoeing is done including earthing up of the crop.

Intercultivation should not be more than 3-5 cm deep so that roots are not damaged. If weed problem is very high we can the herbicides as under:

Simazine (50%) or atrazine (50%) 1.5 kg a.i./ha in 1000 lit of water as pre emergence soil application is recommended.

After application do not disturb the soil for 4-5 weeks.

Plant Protection If maize is produced during winter season, the field remains relatively free from

the insect pests and diseases. However in the summer they predominate and infest the crop heavily.

Apply the appropriate control measures as 0.05% Endosulfan, 0.1% Carbaryl or 0.05% Lindane to control insects and treat the seeds by using Bavistin or Thiram or Captam @2-3gm/kg of seed or spray Mancozeb 75 WP@1.5kg + 0.25kg zinc sulphate in 500 L of water per ha to control diseases.

Major Insects Major diseases

Stem borer Downy mildew

Pink borer Brown stripe

Shoot fly Bacterial stalk rot

Hairy caterpillers Pithium stalk rot

Army worms Leaf rust

Maize bettles Head smut

Hoppers Several types of kernel and ear rot

Leaf blight (Helminthosporium),

Harvesting

Maize comes under physiological maturity stage at about 30-35% moisture content.

If it can be drying efficiently, we can harvest at physiological maturity stage when

the husk turned yellow and grains are hard enough.

In the absence of drying facility, harvesting is delayed until the grain moisture drops

down to 15% level.

Remove the husk from the cobs and then dry in sun for 7-8 days.

Shelling and cleaning

The seed-certifying agency requires an inspection of maize cobs before shelling.

After drying, all off type and diseased cobs should be removed before shelling.

After approval from seed certifying authority the cobs should be shelled and cleaned

or processed.

Seed yield

Under average situation, the seed yield varies from 2.5-3.0 tons/ha.

Seed standard set by Government of NepalMinimum certification standards for maize

Maize seed must be produced from a known source of seed for

certification. One must be in a position to produce a document-like

tag or sale record when demanded by the certified body.

Certification applies only to those release varieties.

STIP is only authorized to certify the seed.

A variety may be eligible for certification if the fields were used to

produce the same variety of certified seed in previous seasons.

The crop should be planted in recommended isolation to check out

cropping.

A minimum of two field inspection should be made; the first at

tasseling and second at maturity.

Minimum seed standard During the ear head inspection at the threshing floor upto one percent

cob of other varieties and two percent cob of other colours is allowed

for certification.

The seed inspector reserves the right to inspect the seeds, at any time,

at threshing floor, processing plant or during storage.

Seed need to be treated with the recommended fungicides and

insecticides.

A respective sample of each lot of seed should be taken and submitted

to seed testing laboratory for complete analysis by authorized seed

inspector. If an amount of seed produced is 40000 kg in a lot then

minimum amount of sample required for general test of seed is 1000 gm

and minimum amount of sample required for purity test is 900 gm.

Similarly for varietal test minimum amount of sample is 1000 gm.

Minimum seed testing standard:

Factors Foundation Seed Certified Seed

I II

Pure seed (minm) 99% 98% 97%

Other crop seed including other varieties (maxm)

0.2% 0.5% 1%

Total inert matter (maxm) 2% 2% 2%

Weed seeds nil nil nil

Germination (minm) 85% 85% 85%

Moisture content (maxm) 12% 12% 12%

Tagging Seed to be sold by an authorized dealer should carry the following identifications:

Validity of tagging:Tagging will be valid only for one season if properly stored.

Seed Tag

Foundation seed White tag

Certified seed I Blue or blue band on one end

Certified seed II Green or green band on one end

Fig.1) Foundation seed Fig.2) Certified seed I Fig.3) Certified seed II

Table:NARC certified maize varieties according to their domain

S.N. Varieties Certified Year Certified Domain1. Khumal Yellow 2022 B.S. Mid hills

2. Rampur Composite 2032 B.S Terai, Inner terai, Basin and Mid hills

3. Arun 2 2039 B.S Terai, Mid hills

4. Manakamana 1 2044 B.S Mid hills ( Terai- winter)

5. Ganesh 2 2046 B.S High hills (Terai & Inner terai- winter)

6. Rampur 2 2046 B.S Terai, Inner terai, Basin and Tars

7. Arun 1 2052 B.S Western terai & Mid hills

8. Ganesh 1 2054 B.S High hills

9. Manakamana 3 2059 B.S Eastern, Central & Western Mid hills (1000-1700 m)

10. Gaurav hybrid 2061 B.S Terai and Inner terai

11. Deuti 2063 B.S Midhills

12. Sital 2063 B.S Hills

13. Manakamana 4 2065 B.S Eastern to Western Mid hills ( below 1600 m)

14. Posilo makai 1 2065 B.S Eastern to Western Mid hills ( below 1600 m)

References:Agrawal, R.L.(2005) Seed Technology, Second edition (page no. 130-134)www.narc.org.npKrisi Diary(2069), Minstry of Agriculture. Minstry of Agriculture.Barsic Bali Bikash Karyakram Tatha Tathyanka Pustika; Barsic Pragati Pratibedan (2066/067) K.R. Regmi, K.K. Sherchhan, Trainer’s Manual Maize , DOA, ATMDP

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