If possible, the hybrid seed production should be taken either in the area where no other maize variety is planted nearby the seed production plot or at least 400-500 metre distance is required between two maize genotypes to maintain the genetic purity.

Parents	:Female Male
	193-1 163
Sowing time	:First week of July in Kharif and First week of November in Rabi in northern India
Seed rate	:Female Male
	15 kg/ ha 10 kg/ha
Method of Sowing
Female: Male ratio	:3:1
Spacing	:Row spacing (East-West direction):60 cm Plant spacing:20 cm
Nutrient Management:	FYM@15 tonnes/ha

N - 200 kg

P2O5 - 80 kg

K2O - 80 kg

Zn So4 25 kg/ Hectare

Total FYM, full doses of phosphorus, potash and zinc and 10 % N should be applied as basal. The remaining dose of nitrogen should be applied in four splits as per details given below to avoid losses and meet the requirement throughout the crop cycle-
1. 20% N at 4 leaf stage
2. 30% N at 8 leaf stage
3. 30% N at flowering stage
4. 10% N at grain filling

Water management

Irrigation should be given as and when required by the crop depending upon the rains and moisture holding capacity of the soil. Light and frequent irrigations are desirable Young seedlings, knee high stage, flowering and grain filling and 10 days after grain filling are the most sensitive stages for water stress for inbreds and irrigation should ensured at these stages. Water should not overflow on the ridges. The irrigation should be applied in furrows upto 2/3rd height of the ridges.

Weeds are the serious problem in maize, particularly in wet (monsoon) season that competes with maize for nutrient and causes yield loss up to 35 %. Atrazine being a selective and broad-spectrum herbicide in maize checks the emergence of both broad leaves and most of the grasses. Pre-emergence application of atrazine @ of 1.0-1.5 kg a.i ha-1 in 600 litre water is effective for controlling weeds. While spraying, the person who is doing spray should move backward so that the atrazine film on the soil surface may not be disturbed. Preferably, three nozzle booms may be used for proper ground coverage and saving time. One to two hoeings are recommended for aeration and uprooting of the remaining weeds.

Insect Pest Management

Stem borer is a serious problem in maize. It can be controlled by 1-2 spray of Carboryl or Endosulfan after 10 days and 20 days of germination. Application should be done in the central whorl of plant.

Ist spray: 500 gm Carboryl or 625 ml Endosulfan (35EC) in 500 liter water.

IInd spray: 750 gm Carboryl or 900 ml Endosulfan (35EC) in 700-800 liter water, if required.
Photo 26. Insecticide application in whorl

i) At early stage i.e. after 12-15 days of sowing, off-type plants and excess plants should be removed and proper plant to plant distance of 20-25 cm should be maintained to provide an equal opportunity to each plant to grow,
ii) At knee high stage and
iii) At flowering i.e. before anthesis

Dissimilar plants should be removed from the male and female lines to maintain the genetic purity of seed. Dissimilar tassel bearing male plant should also be removed.


Photo 27. Rogning operation

Earthing up

One day prior to earthing up, third split of nitrogen should be applied followed by hoeing. On the next day earthing up operation should be completed with movement of the person in the backward direction. This operation should be done before tasseling stage to save the crop from lodging.


Photo 28. Earthing up

Detasseling

Detasseling in female should be done before anthesis. It should be practiced row-wise. One person should follow to monitor the each row to check that no part of the tassel is left inside. The process of detasseling should continue for 8-10 days. While detasseling, leaf should not be removed which will other wise reduce the photosynthesis. It has been observed that the

Male parent should be harvested first than the female and should be kept separately. Optimum moisture content in grain at harvesting should be around 20%. The harvested cobs should spread evenly instead of making heap.

Stages of crop inspection

(i) At the time of sowing: to monitor the land, isolation distance, planting ratio of male: female, proper sowing time, seed treatment

(ii) During pre-flowering/vegetative stage: to verify the rouging and removal of off type plants

(iii) During flowering stage: to check disease and pest infestation

(iv) During post-flowering and pre-harvest stage: to remove the late and diseased plants

(v) Harvesting time: to see the proper time of harvesting

Post harvest management

Drying and sorting of seed parent cobs

The drying of the cobs should not be done either on the kuccha or pucca flour, rather it should be dried on tarpoline sheets to avoid seed injury and during night the cobs should be kept covered. To maintain the purity, dissimilar, diseased and pest infested cobs should be removed before shelling. The female cobs should be dried upto 13-14% moisture content before shelling.

Shelling

Shelling of female parent should be done earlier than male to avoid mechanical mixture. Shelling can be done manually or by power operated maize sheller.

Seed processing: All under size, broken, damaged etc seeds should be removed for maintaining the quality of seed.

Storage and marketing

Seed drying should be done till the moisture content of the seed is reduced to 8 % and it should be kept in aerated jute bags. Seed should be stored at cool and dry place preferably in cold storage. Poor storage conditions will lead to loss of vigour and poor germination. Marketing should be done with specifications and standards.