ESTIMATION OF TOTAL FACTOR PRODUCTIVITY GROWTH IN AGRICULTURE SECTOR IN PUNJAB, PAKISTAN: 1970-2005

Samples collection: Fifty fresh date fruit (Rutab stage) samples from different varieties showing signs of microbial spoilage were collected in sterile bottles from 10 outlets in Hofuf City markets in Saudi Arabia. The samples were transported within one hour to the laboratory and analyzed for microbiological content on the same day. Microbiological analysis: Samples of Rutab (10 g) were weighed into sterile stomacher bags, 90 ml sterile peptone water (CM0009, Oxoid, Basingstoke, UK) added and homogenized in a stomacher (Lab-Blender 400, Seward Medical, Worthington, UK) for 45 second. Aliquots (1.0 or Pak. J. Agri. Sci., Vol. 53(2), 461-465; 2016 ISSN (Print) ISSN (Online) Yeasts involved in spoilage were counted by inoculation on PDA plates and incubation at 25°C for 2-3 days, and then isolates of the dominant strains were identified. Potentially pathogenic yeasts were involved in the spoilage of six out of the 50 samples tested (12%). The yeast counts in these samples were in the range 10 4 to 10 7 CFU/g. The pathogenic yeasts constituted 12 to 100% of these counts, i.e. some samples were spoiled by the pathogenic yeasts only. The dominant pathogen was Candida tropicalis found in three of the six spoiled samples representing 12, 75 and 100% of the yeast population involved in spoilage. C. krusei, Issatchenkia orientalis and C. albicans were each found in one sample making 14.7, 17 and 25.3% of the yeast population detected in the spoiled samples, respectively