UPDATE 1-Shoprite 3-month sales up, sees tough H2

* Increases market share by 1.6 pct

* Non-South African business sales rise 16.5 pct

* Sees challenging H2

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JOHANNESBURG, Oct 26 (Reuters) - Africa's biggest grocer Shoprite Holdings Ltd (SHPJ.J) said on Monday turnover for the 3 months to end-September rose by 15.3 percent, increasing its market share by 1.6 percent.

Shoprite, which operates supermarkets in more than 10 African countries, said sales growth in its non-South African business climbed to 4.3 percent in rand terms, or 16.5 percent at a constant rate of exchange.

However, while market share for the period rose to its highest level of 31.67 percent, the firm said it expected trading conditions to remain difficult until June 2010.

South African retailers have struggled to keep sales rising as a recession in Africa's biggest economy dampens consumer spending. But retailers like Shoprite, which also cater for the low-end market, have fared better than top-end stores like Woolworths (WHLJ.J).

Shoprite shares were marginally lower at 0.37 percent to 63.96 rand by 0752 GMT, in line with a weaker JSE Top-40 index .JTOPI of blue chips. (Reporting by Phakamisa Ndzamela)