Abstract:
A sample study of stem borer infestation of rice crop of 1981 and its expected relationship with loss in yield was studied in 18 representative 16 sq. ft. field plots at Gujju (Sind). The means of data showed that there were 100188 hills per acre, 11.68 tillers per hill, on which the mean infestation was 21.35%. Of the infested tillers 18.46% were 'Dead Hears', 4.18 'White Heads', and 5.46% were late tillers. The mean number of grains per panicle on uninfested and infested stems were 100.74, and 75.61 respectively, with corresponding weights of 2.40 and 32g. The total calculated actual and potential yields turned out to be 2016.62 and 2779.83 Kgs. respectively, showing a loss of 763.21 Kgs. per acre (= 27.45%). The hibernating larvae were present in 4.38% of tillers in stubble, showing a total of 35528.62 larvae per acre. These results on 'Ganjja' variety of rice in lower Sind are in many ways in contrast with those of Rahman and Ghouri (1981) obtained with 'Basmati' variety of rice in Punjab.
Page(s):
33-37
DOI:
DOI not available
Published:
Journal: Pakistan Journal of Scientific and Industrial Research, Volume: 27, Issue: 1, Year: 1984