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State of Environment and Related Issues

Common Name: Maize

Scientific Name:  Zea mays

Description: Maize (Zea mays) is a tall, deep-rooted, warm weather annual grass. A single long stalk will develop from seed. Long smooth leaves are attached at the stem nodes. Seed producing shoots originatefrom the base of the main stem. The female flowers are borne on the corn 'ear', which arises at a leaf axil near the mid-point along the stem. The flower organs, and later the grain kernels, are enclosed in several layers of papery tissue, termed husks. A mass of long styles (silks) protrude from the tip as a mass of silky threads. These strands are actually the stigmas from the flowers and emerge at the same time the pollen from the terminal tassels is shed. The pollen is windblown and comes in contact with the emerged silk or stigma.  Most varieties of corn require 100 to 140 days from seeding to full ripeness of the kernels though some kinds will ripen in as little as 80 days. Corn kernels or seeds vary in size and shape in different kinds and varieties. They may be only an eighth inch long and near round in popcorn to a half inch long and a flattened-cylinder shape in some other kinds. The kernel consists of the following: (1) An outer thin covering which is made up of two layers, an outer pericarp and inner testa or true seed coat. (2) The endosperm which makes up near 0.66 of the total volume. This consists almost entirely of starch, except in sweet corn. (3) The embryo, the miniature plant structure that develops into a new plant if the seed is planted and grows. The embryo is near one side of the kernel in most kinds rather than in the middle. It contains most of the oil in corn.

Common Name: Ragi

Scientific Name:  Eleusine coracana

Description: Annual grass; culms erect, laterally flattened, 60-120 cm tall or long, profusely tillering, in addition to branches sent out at the rounded nodes in succession, plants often lodged or prostrate; root system fibrous and remarkably strong, permeating soil thoroughly, inflorescence a whorl of 2-8 (normally 4-6), digitate, straight, or slightly curved spikes 12.5-15 cm long, about 1.3 cm broad; spikelets about 70, arranged alternately on rachis, each containing 4-7 seeds, varying from 1-2 mm in diameter; caryopsis nearly globose to somewhat flattened, smooth or tugose, reddish-brown to nearly white or black. Different varieties includes PR-202, K-2, Co-2,Co-7,Co-8,Co-9,Co-10.   Ragi grain possesses excellent storage properties and is said to improve in quality with storage. Seed can be stored without damage for as long as 50 years. They are highly valued as a reserve food in times of famine. Yield depends on variety and is directly related to duration, height and tillering capacity of type grown. Types with straight spikes give better yields than those with curved spikes. Ragi is the principal cereal crop for many peoples in India, Sri Lanka, and East Africa. In India over 2.5 million hectares are cultivated annually. Although it does not enter international markets, it is a very important cereal grain in areas of adaptation.

Common Name: Sorghum

Scientific Name:  Sorghum bicolor

Description: Sorghum is a member of the grass family and a native wild plant of Africa. Summer annual, coarse, erect with much variability in growth characteristics; culms solid or sometimes with spaces in pith, 0.6-5 m tall, depending on variety and growing conditions, 5 to over 30 mm in diameter, either dry at maturity or with sweet insipid juice; leaves broad and coarse, similar in shape to those of corn but shorter and wider; blades glabrous and waxy; sheaths encircle Culm and have overlapping margins; panicle erect, sometimes recurved, usually compact in most grain sorghums and more open in forage types; seed covered by glumes that may or may not be removed by threshing; prop roots may grow from Culm nodes; bud at each node from which a tiller may grow; seeds white, yellow, red, or brown; panicle with up to 6,000 spikelet’s. Seeds 25,000 to 61,740/kg. Sorghum is a plant of hot and warm localities. The optimum temperature for growth is 30⁰C and it needs about 250-400 mm rainfall. Excess moisture and prolonged drought are harmful. It is fairly tolerant to alkalinity and salinity. Soils with clay loam or loam texture, having good water retention capacity are best suited for sorghum cultivation. Varieties of sorghum are classified into 4 groups: grain sorghums, grass sorghums, sweet sorghums, and broom corn. Broom corn is grown for the branches of the seed cluster, which are used to make brooms. Sweet sorghums have sweet juicy stems and are grown to be made into sorghum syrup. The syrup is made by pressing the juice out of the stems and boiling it down to the proper thickness. Sweet sorghums can also be made into animal feed or silage. Grass sorghums are grown for green feed and hay but can also be weeds. Two types of grass sorghums that grow in Kansas are Sudan grass, an annual grown for feed and hay, and Johnson grass, a perennial weed. The varieties include Co.1, Co-10, Co-12, Co-17, K-1, K-2.

Common Name: Rice

Scientific Name:  Oryza sativa

Description: Rice can be cultivated under a variety of climatic and soil conditions. Rice cultivation isconditioned by temperature parameters at the different phases of growth. The critical mean temperature forflowering and fertilization ranges from 16 to 20⁰C, whereas, during ripening, the range is from 18 to 32⁰C. Temperature beyond 35⁰C affects grain filling. Rice comes up well in different soil types. For normal growth, a pH range of 5.0-8.0 is suitable. In general, rice can be grown as transplanted or direct sown crop during three seasons depending on the agro climatic situations.