An experiment was carried out for one season (2007) in the Experimental Farm of the Faculty of Agriculture at Shambat to investigate the response of Groundnut (Arachis hypogaea L.) to phosphorus and organic fertilization under irrigation. The treatments comprised two types of organic manures: farmyard manure (FYM) and chicken manure (CHM) at rate of (0, 10 tons/ha), two phosphorus levels (0, 50kg P2O5/ha) in form of triple super phosphate (48% P2O5) and three times of application for Organic manures two months and one month before sowing and at sowing. Phosphorus was applied at sowing. The design was Factorial Split-Plot design with four replications. The organic manure treatments were assigned to the main plots and phosphorus and its combinations treatments to the sub-plots. Parameters studied included: vegetative parameters (number of nodules/plant, nodules dry weight/plant, shoot and root dry weight/plant and number of branches/plant), reproductive parameters (days to 50% flowering and number of flowers/plant), yield and yield components (plant density, number of pod/plant, pod set(%), weight of pods/plant, shelling(%), pod yield(t/ha),hay yield(t/ha), and harvest index), and chemical composition (seed oil, protein and phosphorus contents).
Results showed that application of organic manures significantly increased number and weight of nodules/plant, shoot dry weight, oil, protein and phosphorus contents, while organic manures insignificantly increased root dry weight, number of branches/plant, days to50% flowering, number of flowers/plant, and yield and yield components. Also results showed that application of P significantly increased hay yield, protein and phosphorus contents. Phosphorus also insignificantly increased number and weight of nodules/plant, shoot and root dry weight, number of branches/plant, days to 50% flowering, number of flowers/plant, yield and yield components, and oil content. In addition, there were significant effects of the interaction between P and organic manures on seed oil, protein and phosphorus contents.
Groundnut or peanut (Arachis hypogaea L.) also named monkeynut and earth nut, is a member of the family Leguminosae, sub family Papilionaceae and is a native of South America (Brazil or Peru). It was brought to Africa and Middle East by early travelers from its native area.
Groundnut is one of the most wide spread and important food legumes in the world and the third largest source of edible oil after soybean and sunflower. The seed contains 42-55% edible non-drying oil, 25-32% protein, and appreciable quantities of phosphorous, calcium and vitamins.
The groundnut oil is used as table oil and for the manufacture of soap, margarine and other products such as sweets and butter. The shell may be used as manure, animal feed, a source of energy and raw material source for many products (Vankatanarayana, 1952).
Groundnut hay contains about 7% protein and thus it is a valuable animal feed. The total annual world production amounts to about 25 million tons of unshelled nuts, 70% of which is contributed by India, China and U.S.A (Khidir, 1997). The main producing countries are India, Chaina, U.S.A., Sudan, and Indonesia, and in Africa Sudan, Senegal, Nigeria (FAO, 1998).
In the Sudan, groundnut is one of the main cash crops; it plays an important role in the economy of the Sudan (MANR, 1985). It is produced by two production systems (Khidir, 1997). In the rainfed sector, the crop is grown in small holdings on sandy soils of low fertility, mostly under low and erratic rainfall, where the early maturing Spanish types (Barberton and Sodari) used to dominate the area. In the irrigated sector, groundnut is produced on heavy black cracking clay of central Sudan, where only late-maturing Virginia types (Ashford, MH383, Medani, and Kiriz) are grown.
The main areas of production in the rainfed sector include South Darfur, South Kordofan, North Kordofan and Southern region (Equatoria), while the main areas of production in the irrigated sector include Gezira scheme, Rahad scheme, New Halfa scheme, Suki scheme, Blue and white Nile schemes.
Under irrigated conditions, the average yield ranges between 1.5 and 2.5 tons/ha whereas the yield under rainfed conditions ranges between 0.2 and 0.8tons/ha (Maragan, 1996).
Research work on groundnut in the Sudan covers some aspects such as weed control (Ishag, 1971), plant population (Ibrahim, 1976), nitrogen and phosphorous fertilizers application (Nur and Gasim, 1974; Mohammed, 1980), and the effect of sulphur application (Salama, 1983; Hago and Salama, 1987; Hago and Salama, 1987). However, there is still a paucity of information in the area of groundnut nutrition, particularly organic manuring.
So, the main objective of this work was to study the response of groundnut to phosphorous and organic fertilization under irrigation.