HomeInternational Rice Research Notesvol. 29 no. 2 (2004)

Nursery technology for early production of robust rice seedlings to transplant under integrated crop management

R. Rajendran | V. Balasubramanian | V. Ravi | K. Valliapan | T. Jayaraj | S. P. Ramanathan

Discipline: Agriculture

 

Abstract:

The recently introduced integrated crop management (ICM) for rice has modified certain crop management practices in the system of rice intensification (SRI) developed in Madagascar to enhance rice productivity and increase farmers' profits. It involves transplanting of young (14- to 15-d-old) seedlings at wider spacing, mechanical weeding, intermittent irrigation, etc. Among these, the use of young seed- lings is the single most important practice contributing to high yields. Planting of 15-d- old seedlings at one seedling per hill produced higher rice yield than planting 21-d-old seedlings in North Sumatra, Indonesia (Makarim et al 2002). In the conventional wetbed nursery, seedlings do not attain the expected size (15- to 20-cm height) even at 25-30 d after seeding (DAS) because of invariably high seeding rates and poor nursery management. In Tamil Nadu, India, the seed rate used for the wetbed nursery is as high as 80-100 kg per800-m2 nursery area to plant 1 ha, and the resultant seed- lings are naturally thin and delicate. Therefore, we decided to develop a modified rice mat nursery (MRMN) for producing robust, healthy rice seedlings in 15 d by evaluating different soil + manure + rice husk mixes as a medium for MRMN. A few of the nursery management details such as thickness of the medium, lining of the seedbed, seed rate, and nutrient needs were standardized by nonreplicated preliminary trials.