Markets swung wildly on Wednesday as investors tried to make their mind up whether Tuesday's record gains were something to build on, or a positive blip after weeks of disruption.

The FTSE 100 started the day well, jumping by as much as 5.4%. It later swung into negative territory down 0.8%, before jumping back up to trade around 0.7% up - all before midday.

Traders have come off the back of the best day in the index's history in terms of points gained, and the second biggest percentage increase.

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Tuesday's markets were delighted when it seemed that the US Senate was close to a deal which would likely pump up to two trillion dollars (£1.7 trillion) into the American economy.

Russ Mould at AJ Bell, an investment platform, warned traders need to watch out for a so-called dead-cat bounce where shares fall again after a big rebound.

He said: "Investors will still need to tread carefully. Six of the FTSE 100's 10 single-largest percentage daily gains of modern times came between September and December in October 2008 but the index only bottomed in March 2009 after further heavy falls of nearly 30% as the effects of the collapse of Lehman Brothers and the ongoing global recession continued to hit confidence, corporate earnings and cash flows.

"A hefty rise in the FTSE 100 is welcome, should it transpire, but there remains the risk that any such advance proves fairly temporary should news on the viral outbreak continue to get worse and policy measures require a longer lockdown - and potentially deeper hit to global economic activity - than currently hoped."

There were no obvious themes to which sectors were performing the best. JD Sports took the lead at over 14%, followed by the Royal Bank of Scotland and M&G, all in double-digits.

At the other end of the scale, Rentokil dropped more than 15% despite saying it was going to train up another 2,500 staff members to become disinfectant specialists. It was followed by Melrose Industries and Imperial Brands.

The fishing and seafood industry will receive £5 million from the Scottish Government to help businesses during the coronavirus outbreak.

Demand for Scottish delicacies such as langoustine, prawns and crab has fallen sharply as the export and hospitality markets contract.

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The funding will be offered to 650 companies in the industry, including onshore processing firms.

Owners of vessels less than 12 metres long will receive an initial payment of 50% of two months' average earnings, administered by Marine Scotland.

Fisheries Secretary Fergus Ewing said: "The economic impact of Covid-19 is global and is reaching into the heart of our fragile coastal communities.

"I have spent the last week listening to and liaising with our fishing industry, and there are many who have lost their livelihoods with little prospect of an early recovery. The need for action is immediate.

"I am therefore announcing an initial package of support and Scottish Government officials are working as hard as possible to get this money out of the door as fast as we can."

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He added: "We recognise that more needs to be done, particularly to try and create some alternative markets - at least in the short-term.

"I will be discussing with retailers how that might be achieved, and I would also encourage the public to play their part by buying Scottish seafood if they can.

"By working together we can all play a part in securing the immediate future of some of the key contributors to Scotland's food and drink success."

Energy giant E.On has reported a slump in UK customers over the past year, as profitability was also weighed down by regulatory price caps.

However, the company said total earnings before tax and interest increased to €3.2 billion (£2.9 billion) in 2019.

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It added that it expects earnings to rise again in 2020 but said it had not factored in the current downturn in the economy amid coronavirus fears.

E.On said it has seen customers across Europe consuming less energy as a result of the pandemic.

The company said the energy sector "won't be as hard hit by other industries" but will still feel an impact from the outbreak.

E.ON SE chief executive Johannes Teyssen said: "Industrial and commercial customers are consuming noticeably less energy.

"This will have a temporary impact on our network and sales businesses. There may be delays in our ability to deliver energy infrastructure projects."

The company said it will not disconnect financially vulnerable customers from its network for the time being.

Mr Teyssen added: "Energy utilities have a special significance for critical infrastructure in this crisis and thus a special responsibility. We're Europe's biggest operator of energy networks.

"Their reliability and continuous availability is of paramount importance for healthcare, public order, and people everywhere. We will do everything in our power to ensure supply security, even in this situation."

E.On said its core business saw operating arms post "solid earnings" last year, although customer solutions saw earnings slip by €100 million (£90.9 million) due to price caps and the fall in UK accounts.

The company said last year that it was folding Npower's domestic and small business customers into its own business, in a move which saw it announce 4,500 job cuts.

Sofa seller DFS has frozen new recruitment and training as it tries to get to grips with the potential impact of the coronavirus pandemic.

The business has also "significantly" reduced what it spends on marketing and deferred the opening of six planned showrooms during the 2021 financial year.

It will tap into the government promise to pay staff who are unable to get to work 80% of their salaries, while senior executives have agreed to take a pay cut.