Raising of Seeds in the Nursery/ Field

 

Preparation of nursery Rice can be either transplanted or sown directly in the field. When the farmer decides for transplanting, preparation of nursery is the first step. Basically, three methods of nursery preparation can be adopted. The choice primarily depends on the availability of water.

Wet nursery The wet method can be adopted in areas where water is available as in the second crop season. Seedlings raised by the wet bed method can be harvested one week earlier. The seedbed should be prepared in advance, so that the pre-germinated seeds can be sown in time. As far as possible, fertile lands with irrigation and drainage facilities should be selected for raising the nurseries. Such lands should be suitably located to receive full sunlight. The following are the steps in raising wet nursery.

Plough and harrow the fields two or three times until the soil is thoroughly puddled and levelled. Prepare raised beds 5 to 10 cm high 1 to 1.5 m wide and of convenient length with drainage channels between the beds. The total seedbed area should be 1000 m2 for each hectare of the field to be transplanted.

Apply compost or cattle manure @ 1 kg per m2 of the nursery bed and mix well with the soil at the time of preparation of the field.

Treat the seeds by wet method. Drain and incubate in warm moist place for sprouting. Never allow the seeds to dry up. Moisten them occasionally. Sow germinated seeds on the third day. Delay will result in poor seedling stand.

Irrigation may be commenced on the 5th day after sowing and continued up to the 7th, to a depth of about 5 cm. After this period, irrigate the seedbed continuously to a depth of about 5 cm in order to control weeds.

Drain occasionally to encourage production of vigorous seedlings with short roots. Flooding the soil with too much water for long periods produces tall and weak seedlings, which do not readily recover during transplanting.

If symptoms of nitrogen deficiency are observed, broadcast urea at the rate of 1 kg for 100 m2 as top dressing about 10 days prior to pulling out of seedlings, depending upon the duration of variety.
Dry nursery This method is practiced in areas where sufficient water is not available and the time of planting is uncertain. During first crop season, wherever transplanting is done depending upon receipt of rainfall, it is safer to adopt this method since growth of the seedlings can be controlled.

Plough the nursery area to a fine tilth. Prepare raised beds of 1 to 1.5 m width, 15 cm in height and of convenient length. Apply compost or cattle manure at the rate of 1 kg/m2 of the nursery bed and mix well with the soil at the time of preparation of the field.

Sow the seeds treated as described under dry seed treatment method, evenly over the bed and cover with fine sand / soil.

Water the nursery as and when required depending upon the receipt of rains.

Note: Rice seedlings from solarised nursery beds showed high initial growth, early maturity and resistance to leaf blast disease (ad hoc recommendation).
Dapog Nursery "Dapog" method, otherwise called "soil less nursery" is a method adopted from Philippines. The essential feature of this method is to have a very thick stand of the nursery seedlings without any contact with the soil. Generally, seedlings become ready for transplanting in 12 to 14 days. The method of preparation of dapog nursery is as follows.
  • Choose the suitable site for mat nursery raising (preferably within or nearer to the main field) and puddle the selected site.
  • Raise the puddled soil bed to a level of about 5 cm and level it properly. To lay more than two rows of mats, select each bed width as 1.2m.
  • To cover one hectare of land selected plot should be of size of about 20 x 7.5m with provision of channels of width of 0.5m .
  • Spread the plastic sheet evenly on the leveled and raised beds.
  • Mix the soil with FYM and water to prepare slurry.
  • Keep the DRR designed mat frame (having dimensions of 19 x 50 x2 cm of each block) on the plastic sheet and spread the slurry mixture in each block of the frame.
  • After proper settling, lift the frame to leave the mats behind. Each time, five mats can be prepared this way.
  • Take 100-110 g of sprouted seed and spread it evenly on the prepared mats and press them gently. One hectare of main field needs 500 600 mats.
  • The procedure is repeated to prepare all the mats. Spread either grass or plastic sheet on the mats overnight and take it out in the morning.
  • Do not uncover if there is rain during the first week of mat raising.
  • Sprinkle with rose can on all the mats everyday to keep the mats moist.
  • After a week when the nursery looks green, provide water through channels to the level just below the mats.
  • Apply fertilizer @ 30 g of DAP/ liter of water and sprinkle on the mats with hand sprayer after 7-10 days of the nursery.
  • The nursery will be suitable for transplanting after 15-20 days when the plant reaches height of 12-15 cm.
  • Seedlings raised by this method are very useful when mechanical trans planters are used.
References Kerala Agricultural University.  2011.  Package of Practices Recommendations: Crops.14th edition. Kerala Agricultural University, Thrissur- 360 p.