* Qatar index's drop is biggest since sanctions imposed
* Barwa, Masraf Al Rayan, Al Khaliji go ex-dividend
* Dlala Brokerage tumbles as it decides to pay no dividend
* Saudi banking sector slides for fourth day
* Dubai real estate sector drops, DAMAC hits eight-month low
DUBAI, Feb 28 (Reuters) - Major Middle Eastern stock markets fell on Wednesday in response to weak global equity and oil prices, with Qatar particularly hard hit by several shares going ex-dividend and a brokerage's decision not to pay an annual dividend.
The Qatari index plunged 3.1 percent - its biggest drop since other Arab states imposed sanctions on Qatar last June - in its heaviest trade for a month.
Barwa Real Estate sank 8.7 percent, Islamic bank Masraf Al Rayan lost 6.8 percent and Al Khaliji Bank slipped 6.7 percent as all three stocks went ex-dividend.
Dlala Brokerage tumbled 7.2 percent, despite reporting its annual net profit had more than quadrupled, after its board recommended not distributing a dividend.
But Vodafone Qatar, which had jumped by its 10 percent daily limit on Tuesday in response to positive earnings and licensing news, surged a further 7.5 percent and was the most heavily traded stock by a large margin.
The Saudi index fell 0.6 percent with the banking sector declining for a fourth straight day; all 12 banking stocks dropped, partly because of concern about the government's decision to hand them retroactive Islamic tax liabilities. Al Rajhi Bank slipped 0.9 percent.
But National Industrialisation (Tasnee), which had jumped 9.9 percent on Tuesday after reporting annual net profit soared about seven-fold, added a further 1.2 percent in its heaviest trade since mid-2016.
Insurer Malath surged 6.3 percent after saying it had signed insurance agreements with Abdullatif Alissa Group Holding whose annual premiums would exceed 10 percent of Malath's 2017 sales.
Dubai's index fell 1.3 percent as real estate stocks, hit hard in recent months by slumping property prices, dropped again. Blue chip Emaar Properties slipped 2.4 percent and DAMAC lost 5.7 percent to its lowest level since June 2017.
* Index fell 0.6 percent to 7,419 points.
* Index dropped 1.3 percent to 3,244 points.
* Index edged down 0.03 percent to 4,598 points.
* The index plunged 3.1 percent to 8,653 points.
* Index fell 0.3 percent to 15,473 points.
* Index edged up 0.04 percent to 6,773 points.
* Index rose 0.3 percent to 1,370 points.
* Index gained 0.2 percent to 5,003 points. (Editing by Dale Hudson)