DISEASES AND THEIR CONTROL
Steam rot / cottony rot
It is soil and borne disease. Infestation of basal portion of stem takes place via mycelium that grows with the roots and the stem becomes soft and cotyledon leaves flatten on the ground. At bud formation soft decaying area appears on its stem and base and white mycelia appear later on. The stem becomes weak, leaves dry up and drop off with strong wind.
Infestation takes place on heads when fully developed and seed formation has taken place. The back of head becomes soft and turns brown. Fungus like cotton appears and seeds are also infested. The sclerotia of this pathogen, almost of the size of sunflower seed are produced in abundance which are visible in pith of rotton stem and also in the infested head. The affected tissue turns black and shredded. This disease can be effectively controlled by treating seed with thiram @ 2 g/kg seed before sowing.

Root rot or charcoal rot.
It is soil borne disease that infects the roots. Roots turn brown and rot. Infection at early stages kills the seedlings rapidaly. This also causes neck rot i.e. stem rotting immediately behind the head where infected stem turns brownish and darker towards the base. Roots turn grey and stunted. At later stages, it causes premature ripening, smaller and poor filled heads and a lower yield. For its control, treat the seed with Thiram @ 2 g / Kg seed and avoid moisture stress.

Head rot
High humidity and injury to plants favour infection at lower surface of head where it is attached to the stem. irregular water soaked spots appear, which gradually enlarge and become soft. Shredding of back of heads takes place. Cracking of front side is also common. Seed filling is affected severely and seeds remain small and shrivelled.The yield losses range from 20 to 60 percent and oil reduction to the tune of 25-53 percent and increase in free fatty acids, which is undesirable. To avoid this disease plough the soil with furrow turning ploughto bury the debris of previous crop and residues of sunflower; treat the seed with Thiram @ 2g/kg seed; avoid excessive stress of irrigation; grow recommended hybrid and don't grow sunflower repeatedly in the same field; Spray with Indofil M-45 @ 625 g per hectare in 250 litre of water at 15 days interval starting at about 60 days stage.

UTILIZATION
Sunflower crop has many uses :
- Edible oil of sunflower is of superior quality because of anticholestrol and non-cholestrol contents and is thus preferred over other oils for cooking food.
- Its oil is used for making vanaspati, soap and other allied products.
- Its oil is used in the manufacturing margarine.
- Sunflower meal in the form of cake is used for animal feed or manuring field.
- Hulls and stalks are used for the preparation of furfural.
- Green plants are used as forage or silage.
- Dry stalks are used as fuel.
- Pulp is also extract from plants.
- Sunflower husk finds use in the preparation of ethyl alcohol and yeast.
- Salted and fried kernels of sunflower are eaten as such and its meal is used for confectionery.
- The concentrates and isolates of defatted meals are used for protein additives, meat analogues, meat extenders, emulsifying agents, bakery products, beverages, snak products, etc.
- Seed is included in many commercial bird feeds.

EXPLOITING MALE STERILITY. Sunflower being a Cross-pollinated crop can be exploited for increasing the production of edible oil by developing hybrid sunflowers. The development of commercial hybrids is only possible by using male sterility, and fortunately such genetic systems are available in sunflower. Two types of male sterility occur in sunflower: (1) genetic male sterility linked with certain marker genes. This sterility is due to a recessive nuclear gene and linked to the green colouring matter in the seedling; (2) the cytoplasmic male sterility was first obtained from the interspecific cross H. petiolaria x H. a.n.nuue by Leetereq in France in 1965. This type is being widely used in developing hybrid sunflowers all over the world. Work on the development of hybrid sunflower is in progress at the various centres of the A.I.C. O.P..P. 0. (Sunflower).

GEOGRAPHIC ORIGIN. The Niger (Guizotia abyssinica L.F. Cass. crop is said to be indigenous to tropical Africa and more specifically to Ethiopia.

ECONOMIC IMPORTANCE. The crop is grown for its seed, used for extracting oil which is about 37 to 43 per cent of the seed weight. The oil is used for culinary purposes, for anointing the body, for manufacturing paints and soft soaps, for lighting and lubrication and for manufacturing cosmetics. The oilcake is a well-known cattle feed. The crop sheds a large quantity of dry leaves in the field and thereby adds organic matter to the soil.

BOTANICAL DESCRIPTION. Niger belongs to the family Compositae. The plant is a stout, erect, smooth orscabrous leafy annual herb, about one metre tall. The leaves are opposite or the upper ones are alternate. The capitulum is peduncled, axillary and terminal heterogamous. Bay-florets are pistillate, scriate, fertile; ligule 2-3 toothed and yellow. Disc florets are hermaphrodite, fertile; limb campanulate and 5-fid. Achenes are glabrous, dorsally compressed, tip rounded, pappus absent.

DISTRIBUTION, AREA AND PRODUCTION. India is considered to be the chief Niger-producing country in the world, with an area of 4.8 lakh hectares, and with an annual estimated production of 1.2 lakh tonnes of seed. It is mainly grown in the states of Madhya Pradesh, Bihar, Maharashtra, Orissa and Tamil Nadu, of which the largest area of 2.38 lakh hectares is in Madhya Pradesh.

CLIMATE AND SOIL. Niger is grown as a kharif crop under rainfed conditions. A moderate rainfall of 1,000-1,250 mm suits this crop and, as such, it is not cultivated in regions of heavy rainfall.

Light red soils and brownish loams with sufficient depth and good texture are considered suitable for this crop. It is often grown on poor soils of coarse texture. It can be grown on well-drained heavy soils.

CULTIVATION. Niger is grown either as a pure crop or is grown mixed with minor millets. Two to three ploughings are enough to prepare the land for sowing. The field is made weed-free and levelled by planking before sowing. The crop is sown from June to August, either behind a country-plough or with a four-coultered drill. A spacing of 30 cm between lines and that of 10-15 cm between plants in the line are generally adopted. A seed-rate of 7-8 kg per hectare is adequate to maintain a good crop-stand and a pure crop. About a fortnight after sowing, thinning is done to regulate spacing between plants. One or two hoeings are required for controlling weeds. In general, the Niger crop is not manured. But the application of 20 kg of N and 20 kg of P₂O₅ per hectare is recommended for obtaining higher yields of the crop. When sown as a mixed crop, Niger shares the manuring given to the main crop. The crop matures in November and December. The mature plants are cut with sickles at the base and heaped in the threshing-yard for a week. They are then spread in the sun to dry for two to three days, threshed by beating with sticks, and winnowed.

YlELD. The average yield of Niger is about 200 kg/ ha, but under favourable conditions and with best management practices it yields up to 600 kg.