Introductiion
Botanical Name : Zea mays Linn.
Local Name : Makkai
Hindi Name : Makka
Family : Poaceae
Introduction
Maize is ranked second to wheat among the world cereal crops (FAO 1986). Some 70 countries produce maize 1,00,000 hectares or more, 53 from the developing nations. Developed market economies account for 30% of the global maize area, but provide 50% of the total production as their average yields is three times higher than the world average. Developing nations accounted for 60% of the world total maize area, but produce only 40% of the global harvest (Timothy et al., 1988). In 1996, the total area under maize production was 141,116,000 ha with a total yield of 590,091,000 metric tons of which 266,214,000 tons were harvested for grain.
The distribution over the continents reflects the relative importance attached to maize in the different regions. North America with 41,064,000 ha produced over 50% of the world’s production in 1998. It had a mean yield of 6.48 tons/ha. South America had 19,612,000 ha under maize (2.88 tons/ha), Europe had 13,251,000 ha (4.783 tons/ha), Africa 24,879,000 ha (1.63 tons/ha), Asia 42,203,000 ha (3.82 tons/ha) and Oceania with 83,000 ha (6.22 tons/ha) (USDA 1998). According to the USDA-ARS, the 9 billion bushels per year of maize produced in the US are valued at 30 billion dollars. Maize is also the chief export crop of the US. The maize exported exceeds all the maize used domestically for food, seed, and industrial purposes. Over half of maize used domestically is used as livestock feed (USDA, 1999).
Sixty four percent of the maize produced in the world and 72% in the developed markets is used as animal feed. Less developed countries use 48% of their grain maize for animal feed and Eastern Europe and former USSR use 79% of their maize for animal feed. Maize used directly for human consumption accounts for only 21% of the world maize production. Developed markets, less developed countries and Eastern Europe and former USSR use 14, 40and 4% of the maize produced directly as human food (CIMMYT 1993/94).
United States is the largest producer of maize in the world. In 1997, US planted 80,227,000 acres to maize. Of those, 78,720,000 acres were harvested for grain while the remaining 5,758,000 acres were used for silage. The leading state with highest acreage of maize was Iowa (12 million acres) and the lowest was Montana with 14,000 acres. The average national production was 127 bushels/acre. The production varied a lot across states with some states producing as much as 195 bushels/acre (Oregon) and as low as 123 bushels/acre (Indiana) (Corn refiners association 1998).
Crop Season:
In the Sikkim Condition, maize is a major cereal crop during the Kharif (rainy/summer) season as rainfed crop. The season starts with February-march and ends with July-august depending upon the altitude.
The following is the consumption pattern for maize produced in India at present:
Human Consumption 35%,
Poultry Feed 25%,
Cattle Feed 25%,
Food processing (corn flakes, popcorns, etc) and 15%.
Origin and History:
Grains of maize and parts of maize ears were found in caves and rock shelters during archeological excavations in Mexico. When Columbus discovered America in 1942, maize was already cultivated in American Continent, indicating its antiquity. It is a staple food crop of the indigenous people of Mexico, Central & South America, supporting its origin in this region. But it spread from America to Spain, Portugal, France, Italy, Europe, North Africa and India.
With the existence of Murali maize in Sikkim, Bhutan and other north Eastern states which resemble the primitive hypothetical maize gave another thought of origin. It is believed that Sikkim and other north eastern states to be the secondary centre of origin of maize, however the recent evidence show the possibilities of its pre Columbus introduction through the Atlantic Arabian route. From India it went to china and later it was introduced in Philippines and East Indies. Now it is being grown in USA, china, Brazil, Argentina, Mexico, France, South Africa, Russia, Romania, Yugoslavia and India.
In India the major area of the crop is confined to Gujarat, Rajasthan, Punjab, Haryana, M.P., U.P., H.P., A.P., J&K., Bihar and Sikkim.
Evolution:
The wild relatives or progenitor of cultivated maize is unknown although several theories have been put forward:
i) Hybrid origin theory:
It was once thought that Z. mays descended from a hybrid between Teosinte (Euchlaena mexicana) and unknown wild plant. After successful hybridization of maize & Tripsacum on one hand and intensive analysis of gene difference of maize, Trypsacum and Tiosinte on other hand, Mangelsdorf and his co-workers came to a conclusion that Tiosinte could not be the progenitor of maize.
ii) Mutation Theory:
Mangelsdorf and Reeves proposed that cultivated maize might have derived by mutation from a wild form of maize or pod corn which is abundant in eastern slopes of Andes & South America. They also showed that Teosinte is a natural hybrid of Zea & Tripsacum which occurred after cultivated maize was brought to Central America by traders.
iii) Divergent Evolution:
Weathermax opinioned that Zea, Tripsacum and Euchlaena arose from some common ancestor by divergent evolution.
Adaptation:
Maize crop has a wide range of adaptability. In Sikkim, maize is extensively grown in the altitude ranging from 300 to 2400 m above mean sea level (Lachung) with more than 80 per cent in the mid-hills. The acreage is higher in the drier belts of South and West Sikkim. It is also cultivated in paddy lands prior to Kharif season at the lower hills up to an altitude of 900 m. As of now, maize is not grown at lower altitudes perhaps due to lack of irrigation facility. Maize is cultivated during kharif in the non-paddy lands both as pure and mixed crops, and pre-Kharif season in the paddy lands at mid and lower altitudes. It is also grown in the post-Kharif season at the lower and mid altitudes after the harvest of the main season maize crop. Such maize is cultivated with pulses and beans. Where irrigation possibilities exist, short duration Rabi maize can be sown at lower altitudes before October first week.
Since 1970 there has been an increase in the area under maize and production. The increase in area under maize was basically due to increased area of pre-Kharif maize in the paddy lands. In the main season, maize area under non-paddy lands is diminishing. The period 1981 to 1990 witnessed 27.6 per cent increase in the acreage with 174.3 and 111.1 per cent increase in total production and productivity. This was the period of introduction of the HYVs in to the State. But the increase in production and productivity could not be sustained during the next decade 1991 to 2001; during this period only 31.7 and 22.3 per cent increase, respectively was recorded. This was despite more choice of HYVs being available during the latter period.
Crop improvement work in Sikkim:
In Sikkim, the acreage and productivity are low when compared with other maize producing states in India and other countries. In fact the rural mass of the state breed and bread on maize as their staple food supplemented by little paddy, wheat and minor millet. Not only the human being but also the domestic animals are mostly fed with maize. Keeping in view the importance of these cereal crop in the state, government is giving prime importance on production and protection by evolving high yielding varieties suitable for different elevation and pockets, giving due importance of the following points:
Liking of white grain type by the farmers of the states as it is used as rice after grinding and taking it alone or by mixing with rice.
Keeping quality of the grain as maize is harvested during monsoon to avoid fungal and insect infection due to high percentage of humidity.
A good husk covers to avoid rottage as the state experiences high rainfall condition at the time of harvest.
Hybrid Maize
Hybrid Maize variety C-1415 and C-1837 was taken up during 2005-2006 which showed good result and popular among the farmers. During 2007-2008 Hybrid Maize Seed production was initiate in two Government Farms. During 2008 -2009 25 hectare of hybrid Maize seed production was taken up in farmers field. The ICAR maize research centre Gyalshing, West Sikkim has identified a composite varieties, NLD (stand for NL Dhawn, a leading maize scientist) selected out of 650 lines received for advanced trial during 1978 Kharif. The variety was further selected and multiplied which has virtually replaced the new newly introduced Vijay composite as it could fulfill the above three points noted for ideal variety.
The composite varieties are developed from the superior genetic bases and varieties of maize and constitute a superior gene pool. Composite maize has an advantage over hybrids mainly on the ground that the seed can be used up to six generations unlike hybrids and farmer need not purchase fresh seed every year. He can retain his seeds himself which can produce almost equal to that of hybrid seed. Other advantages are wide range of selection as per his desire with composite which is lacking in hybrids, comparatively cheaper seeds and easy availability of seeds.
The governments of Sikkim have started several programmes for the development of maize in terms of variety and production under Macro Management Programme of this state which is discussed below:
Accelerated Maize Development Programme (AMDP):
This is an on going programme under macro management of agriculture in Sikkim. The objective is to improve the production and productivity potential of maize in Sikkim and to transfer the improved production technologies at the farmers’ level. The various components under AMDP as per the guidelines of the scheme are as follows:
Block Demonstration: The demonstration on high yielding varieties or bio-seed of maize are conducted in potential maize growing areas of four districts of Sikkim.
Integrated pest management: IPM on Maize are taken up in all the four district of Sikkim. An assistance of Rs.1500/ha are provided to demonstrate IPM practices.
Distribution of Maize Shellers: Under this component manually operated maize Shellers are distributed to the farmers.
Farmer’s Training: Twenty trainings with a total of 50 farmers in each batch @ Rs. 15000/ batch in all four districts are taken up. Under this, leaflet and pamphlet will be distributed to the farmers.
Publicity through electronic media: Publicity of AMDP, its objectives and dissemination of technologies to increase the production and productivity of maize will be taken up through printed literature and electronic medias.
Classification of Maize: The genus Zea is a monotypic belongs to tribe maydeae of family Poaceae (Graminae). Sturtevant classified the maize into seven groups based on the endosperm characteristics. These are described below:
Dent corn (Zea mays var. indentata): It is called dent corn because of dent depression on the top of the kernel. The colour of kernel may be yellow or white. The kernel has hard outer starch & soft inner starch. The dent on the crown of the kernel is the result of rapid drying and shrinkage of the soft starch. Dent corn is very widely grown in USA and stores well.
Flint corn (Zea mays var. indurata): It is predominant in Europe, Asia, Central and South America. The kernel is hard but smooth. It has little soft starch. Most of the commercial maize is grown in India belongs to flint corn.
Pop corn (Zea mays var. everata): Pop corn has small grains with hard outer layer. It has higher % of hard starch than flint corn. The hard starch has moisture which on heating expand and explode resulting in pops. Its cultivation is mainly confined to the new world.
Flour corn (Zea mays var. amylacea): It resembles to the flint corn in appearance and ear characteristics. The grains are entirely composed of soft starch alone and have a little or not dent. Flour corn is one of the oldest types of maize grown in USA and South Africa.
Sweet corn (Zea mays saccharata): The endosperm is composed of sweetish starch and characterized by a translucent, horny appearance when immature and after maturity the kernel become wrinkled. The crop is mainly grown in northern half of the US of America. The cobs are picked up green for canning and table purpose.
Pod corn (Zea mays var. tunicata): This may be oldest domesticated maize but it is not grown commercially at present. Each kernel is enclosed in pod or husk in the ear which in turn enclosed in husk like other types of corn.
Waxy corn (Zea mays var. ceratina): The kernel look to have waxy appearance with gummy starch in them because of amylopectin, where as common maize starch is about 78 % amylopectin and 22 % amylase. Its origin is supposed to be in china but many waxy hybrids developed in USA are producing starch similar to that of tapioca and are grown commercially.
Baby corn (Zea mays): The unfertilized young ear obtained from sweet corn or other corn is called baby corn. This is rich in minerals and vitamins and can be harvested within 45-50 days after sowing for marketing. The ears are removed within two days of tasselling and used as salad and vegetable or for soup making. It can be preserved in 1.5% saline solution and can be used at later period.
Area and Distribution: Maize is one of the most important cereal crops of Sikkim. It is grown over an area of about 36,000-40,000 hectare which is about 35-40% of total cultivable area. The production of maize is recorded 16500 tones during 1970 – 1980, 45260 t during 1981 – 1990, 59.61 thousand tones during 1991 – 2001 and 61100 t in 2005 – 06 and 64890 t in 2006 – 07. The distribution of district wise area and production of maize cultivation in Sikkim is given below:
Table 1 District wise Area of maize Cultivation in Sikkim
Sl. No. District Area in 000’ hectares Production in 000’ tones Yield / hectares in kg
1. North 1.81 3.00 1657.46
2. East 8.76 13.73 1567.35
3. South 17.28 26.86 1554.40
4. West 13.00 21.30 1638.36
Total State 40.85 64.89 1588.49
Source: Annual Progress Report 2006-07, Food Security and Agriculture Development Department, Govt of Sikkim.
Use and importance
Versatility of maize grains is well known. Four different types of maize are grown in Sikkim viz., flint or semi-flint corn, sweet corn, popcorn and baby corn. In Sikkim the local uses are many. Maize grains are broken into small pieces on a stone grinder and hand-pound is consumed as rice or mixed with rice in a 50 : 50 ratio. The green cobs are consumed extensively as the main food both in the roasted and steamed forms. The green cobs harvested at the milk stage are ground to make ‘chapattis’ or local bread. It is also used to brew local liquor either solely or in combination with millet. ‘Sattu’ or ‘champa’ prepared by grinding maize to powder form alone or with wheat and/or barley, is consumed along with tea. It is considered to be highly nutritious used as infant food. Dry grains are partially roasted in oil and then hand-pound into thick cup-shaped form and eaten with hot tea. The cobs with multicolored grains have aesthetic value and can be used for indoor decoration. The grains apart from food as bread, pops and gruel, are used for many industrial products like extraction of oil, manufacture of starch, syrup, alcohol, acetic acid and lactic acid, glucose, paper, rayon, plastic, textiles, adhesive, dyes, synthetic rubber, raisins, artifice leather and boot polish.
Nutritive Value
Composition of Maize grain
Sl. No. Nutrient Element Food value
1. Moisture (%) 14.9
2. Protein (%) 3.6
3. Fat (%) 1.5
4. Minerals(%) 2.7
5. Fiber (%) 0.5
6. Carbohydrate(%) 66.2
7. Calcium (mg/100g) 10
8. Phosphorus(mg/100g) 348
9. Iron (mg/100g) 2
10. Calorific value 342
11. Vitamin B complex and E Small amount
Source foods that heal – The natural way to good health by H.K. Bakhru, 1996.
Botanical description
Maize is an annual plant belonging to the family Poaceae. It consists of the following vegetative parts:
Roots
The first root to come out is Radicle which is soon followed by seedling root or seminal root. These seminal roots are later replaced by permanent adventitious roots that are originated from the crown present at the end of Mesocotyl. The lateral root branches profusely, spread widely and penetrate deeply into the soil, though depth of penetration depends on the moisture status of soil. Lesser the moisture deeper is the penetration of roots into the soil and vice versa. Besides these root the plant produce “prop or brace” which are adventitious in nature and are produced on first 2 or 3 nodes of the plant above the soil surface. They help to anchor the plants more firmly into the soil.
Shoot
The stem is made up of nodes and internodes and is filled with pith. The internodal parts are flattened on the side next to the leaf sheath. The plant grows to a height of 1.5 to 3 meters depending upon variety. Rarely they form tillers, if the main shoot is damaged.
Leaf
The leaves grow alternately on the opposite sides of stem. They bear small hairs on them and number of leaves varies from 10 to 20. The width varies greatly with the varieties, fertility status of soil, climatic conditions and management practices etc.
Inflorescence
The maize plant bears two types of inflorescence. First one is the staminate or tassel containing male flower which is always terminal and therefore only one tassel is found per stalk from where pollen grains fall on the ear or female flower. Second is pistillate inflorescence or female inflorescence which develops into an ear and they are borne at the leaf axil about six node below the tassel and on a short branch known as shank. There may be more than one per stalk depending upon variety and management practices. The Sikkim Primitive maize, known as “Murali Makka” bear 4 to 5 cobs/plant. However, its ears are the shortest and grains are the smallest. The shank consists modified leaves enclosing ear and are collectively known as husk. The pistillate spikelet is borne on a thick axis called cob. Each spikelet produce two flower one of which is abortive and the other bears the usual floral parts i.e. glume, palea, ovary, style and stigma. The styles are very long which come out of the husk and are collectively known as silk. The stigma is branched and hairy. It is a cross pollinated crop but self pollination also occurs. The silky structure of female flower traps the pollen grains by small hairs and by the moist, sticky nature of the surface. The pollen grains germinate rapidly, producing the pollen tube which grows down the silk channel to fertilize the female flower.
Grain
The union of the sperm nuclei of the pollen tube with the egg and polar nuclei gives embryo and endosperm, respectively. The maize kernel is morphologically a fruit because it develops from the ovary in which the ovary wall adheres tightly to the seed coat. A single maize seed is capable of producing up to 1000 similar seeds. The seeds or mature kernel of maize consist of pericarp, endosperm and an embryo. For the new plant endosperm serves as a food reserve.
Growth and development phase of maize
A growing plant of maize passes through the following growth and development phases
Seedling stage
This is the sprouting stage which comes about one week after sowing and the plant have about 2 to 4 leaves at this stage.
Grand growth stage
This is knee height stage of the plant which arrives about 35 to 45 days after sowing. Plants need first top dressing of nitrogenous fertilizer and final weeding cum earthing up. This is a critical stage of maize growth. Boosting the growth of plants at th8is stage by proper irrigation, fertilization and weeding will reflect in higher yield.
Tasseling stage
This is more technically called as flowering initiation stage at which the tassels or male flower come out. Final top dressing should be done at this stage.
In Sikkim, infestation of stalk borer is seen during this stage. The laevae may remain inside the whole and start damaging the tassel stalk. Application of Neem oil 2 % would minimize the incidence.
Silking stage
This is also known as cob initiation stage at which the female flowers or cobs are formed. These are axillary flowers unlike tassels that are terminal ones. Usually they are formed in the axis of 11th to 13th leaf whereas male flowers or tassels are formed at the apex after 14 or 15 leaves have came out.
Soft dough stage
This may be also called as milky stage which commences after pollination and fertilization are over. Grains start developing but they do not become hard. This stage may be guessed by seeing of silks and the top of the cob and leaves remains partially green. This is the best stage for harvesting green cobs for table purpose.
Hard dough stage
This is maturity stage at which the leaves get dried, silks vanish or they get dried completely and become very brittle. Harvesting should be done at this stage.