Groundnut

Land Preparation

• Number and depth of ploughings depends on weed intensity, size of the crop seed to be sown, rooting pattern of the crop, type of tilth required.
• Minimise number of ploughings as far as possible in order to reduce cost of cultivation since certain crops may not require thorough fine tilth.
• Summer ploughing is always advantageous and hence take up wherever possible. Summer ploughing is very common if summer showers are received or profuse irrigation water is available.
• After initial ploughing wait for 4-5 days in order to reduce moisture content of the clod and subsequent ploughings and harrowings better physical condition of soil could be obtained with less operations.
• Harrowing of soil should invariably followed after each ploughing facilitates to reduce the clod size.
• Tillage operations should be repeated when the weed seeds are just germinated.
• Whenever it is possible plough the land immediately after harvesting of the previous crop.
• Initial ploughing should not be carried at excess or under moisture conditions.

• Country plough
• Gorru without seed hopper
• Guntaka (Blade harrow)
• Cultivator (Tractor drawn)
• Mould board plough (Tractor drawn)
• Ridge plough (If the crop planted on ridges)

• Levelling helps in irrigating the fields with high water use efficiency. Also helps in draining excess water without stagnation in heavy rainy days or immediately after giving irrigation.

• An ideal soil physical condition with adequate supply of moisture, oxygen and optimum soil temperature and freedom from mechanical impedance is necessary for good seed germination, seedling emergence and root growth.
• Optimum plant population of groundnuts can be established with a seed bed having good tilth.
• Objectives of land preparation includes complete burial of all crop residue and weed seed as well as the applied lime and fertilizer, and the formation of a deep, friable, smooth, levelled but slightly raised seedbed to provide maximum moisture retention, precision planting, for efficient seed germination and for effective weed and disease control.
• The rainfall intensity and soil type determine the type of land preparation for rainfed groundnut.
• In parts of India, after the harvest of the previous crop, soil is prepared by ploughing and harrowing several times before sowing of groundnut.
• Ploughing may be carried out after the receipt of premonsoon rains in May. The land is ploughed 2 to 3 times or more, followed by working with blade - harrow twice.

• In black soils, instead of ploughing, blade-harrow is worked several times after the receipt of South - West monsoon rains. After the land is turned deep with a mould board plough equipped with a litter burial device, the final seedbed is prepared to accomplish a completely flat level bed with wheel tracks established by tracking off the land immediately after turning or by using precision power - driven rotary tiller.
• Only the rows are ploughed and inter - row spacing is cleared of weeds by harrowing. The available organic residues, farm - yard manure and fertilizers are ploughed into the row before sowing groundnut.
• The set - line cultivation has been found to increase infiltration rate in the row and thus more moisture is conserved. The general fertility of soil in the row increases. The inter - row spacing may be reduced up to 60 cm for virginia - runner types and 45cm for spanish - bunch type groundnut.
• Groundnut crop requires a thorough preparation of the soil before sowing. Higher pod yields and lower loss of pods were reported by using mould-board plough for land preparation as compared with the disc - harrow.
• also higher groundnut yields were obtained when land was ploughed with a mould-board plough in the fall (December) than when ploughed in the spring (March), though the yields were not influenced by the method of land preparation.
• A depth of soil preparation beyond 15 - 20 cm is generally not considered for groundnut cultivation, since deep ploughing tends to form pods in deeper layers, rendering the harvesting of groundnut crop more difficult.

• The number of ploughings did not influence the pod yield of groundnut and spraying of gramoxone at 2.5 litres / ha was as effective as all the tillage methods tried.
• The rainfed groundnut could be sown on the sandy - loam soils of Tirupati (India) immediately after receipt of the rains without loss of time in land preparation.
• The weeds can be effectively controlled by either alachlor at 2 kg / ha or nitrofen at 1 kg / ha with supplemental hand weeding to obtain pod yields comparable to conventional tillage of four ploughings with country plough.

• Preparation of medium - textured soils in the command areas of irrigation projects as well as the saline soils with poor drainage poses problem.
• Clods are formed when the soil is ploughed at more than optimum moisture content. The puddled soils in the case of rice as a previous crop have more moisture (22.6%) than the unpuddled soil (16.3%).
• These soils dry much slower, the ploughable soil moisture range reaching after 4 and 10 days, respectively.
• Puddling black soil decreases the infiltration rate by about 4% and reduces the percentage of non - capillary pores.
• The puddled soil thus retains more moisture than the unpuddled soil, considerably delaying the tillage operations for the subsequent crop.

• Unfavourable physical condition of the surface soil hinders the pegging process. The pegs containing the fertilized ovary must penetrate the soil surface 2 cm deep before the pods can develop.
• The surface soil becomes hard, especially in sandy-clay loams when there is a prolonged dry spell during the crop growth. One centimeter of the soil beneath the groundnut plant dries to wilting point within about 48 hours of the rain and peg penetration is hindered if the prolonged dry spell coincides with the peg elongation and penetration phases.
• The bulk - density of the surface soil exceeding 1.6 g / ml have been reported to hinder peg penetration significantly.