| Gouri - A new high yielding multiple resistant rice variety for Kuttanad |
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In Kuttanad, the coverage of high yielding varieties and realization of yield potential are already high when compared to the other rice growing tracts of the State. The yield potential of the tract also is very high which could not be realized fully due to several reasons, the most important one being the pest and disease problem of Kuttanad which is highly complex, characterised by the incidence of a multitude of destructive insects and diseases. Since weather conditions also influence the pattern of seasonal incidence of pests and diseases, especially during the Punja season, the pest and disease problem attains serious proportion and considerable efforts and expenditure are required for controlling and managing these pests and diseases. Widespread use of plant protection chemicals causes environmental pollution, as well as irreparable loss of natural enemies. The cheapest, easy and the most successful plant protection measure against pests and diseases is the use of resistant varieties-which is the first step in the Integrated Pest Management.
Keeping in mind the severity of damage that can be caused by diseases like sheath blight, sheath rot etc. breeding for multiple resistant rice varieties was initiated at Rice Research Station, Moncompu in 1986-87. Hybridization work was carried out between high yielding varieties like MO 4, MO 5, MO 6, MO 7, IR 8 and Jyothi and varieties/cultures with multiple resistance like Ptb 18, Ptb 33, IR 5, IR42, IR 50, Cul. 1954, Cul. 25331 etc. Selections were made adopting pedigree
method and the progenies were evaluated during subsequent years. After attaining uniformity, the cultures were tested in various yield trials viz., Initial Evaluation Trial, Preliminary Yield Trial, Comparative Yield Trial, Multi-locational trials and Farm Trials, KAUM 38-4-1 (MR 1) consistently out yielded the local checks in all the above trials and was included for
National Trials as IET 15923 during Khariff 1997. Here also the culture showed its superiority with respect to grain yield and disease resistance. The culture was released as Gouri (MO 20) for commercial cultivation by the State Seed Sub Committee during September 2002. A hybrid derivative of Bhadra/Cul. 25331 (Mutant of Oorpandy), Gouri is semi tall, has a duration of 115-120 days and
has an average yield of 6-6.5 tonnes per hectare. It has good quality characteristics comparable to other HYVs of the State.
Agro techniques forGouri
Since Gouri is photo insensitive it can be cultivated during all the three seasons of Kerala. In Kuttanad, Gouri can be cultivated during both the seasons, under direct sown as well as transplanted conditions. Under transplanted conditions, 20 days old seedlings should be planted in the main field at a spacing of 20x15 cm. The nutrient requirement is 90:45:45 kg. NPK per hectare. It is highly suited for cultivation in the sheath blight endemic areas, since it is tolerant to sheath blight disease which is a serious threat to rice production in Kerala. It has moderate resistance to sheath rot and gall midge and resistance to BPH. Due to its culm strength, there is no risk of lodging.
Both Breeder and Foundation seeds of Gouri are being produced at Rice Research Station, Moncompu and seeds will be available for further multiplication during April-May 2003. For booking seeds, contact the Professor and Head, Rice Research Station, Moncompu, Thekkekkara, Alleppey Dt - 688 503.
by R. Devika, N. Rema Bai and S. Leenakumari