Pubco Corp., a large printing and graphic arts company based in Glenn Dale, has reported substantial increases in profits during the fourth quarter and all of 1978.

For the year, Pubco earnings from operations were $716,084. When combined with a loss of $159,645 from discontinued operations, operating profits were $556,439 (27 cents a share) compared with $119,010 (5 cents) in the 1977 period.

Final net income for 1978, including a tax credit related to previous losses of $619,800, was $1.18 million (42 cents), a gain of 292 percent from $300,010 (9 cents) in 1977, which had a tax credit of 181,000. Sales for the year rose 11 percent to $53 million.

In the final quarter of the year, Pubco had operating profits of $212,229 (8 cents a share) and a tax credit of $359,800, for total net income of $572,079 (21 cents) vs. operating profits of $35.386 (1 cent) and a tax credit of $83,000 for total net income of $119,186 (4 cents).

Pubco said all of its nine printing and publishing subsidiaries operated profitably last year. The company has graphic arts plants in New York, Pennsylvania, Missouri and Illinois in addition to the D.C. area. Its best-known operation is Merkle Press.

International General Industries Inc. and Financial Security Group Inc., two affiliates of Washington-based International Bank, reported record results for 1978.

IGI, with diversified industrial operations and investments, said profits from continued operations rose 48 percent to $10.2 million (5.76) compared with $6.9 million ($3.89) the previous year. Revenues rose 17 percent to $99 million.

In 1977, IGI suffered a $2.8 million loss from discontinued business, which reduced net income that year to $4.1 million ($2.31).

For the fourth quarter alone, the strongest ever for IGI, profits rose 81 percent to $3.3 million ($1.84) from $1.8 million ($1.01). President Frank Taylor attributed the gains to more efficient production processes and marketing activities at Avis Industrial Corp., Klikok Corp. and Foster Wheeler Corp. (owned 10 percent by IGI and affiliates).

Avis manufactures metal parts and equipment for transportation while Kliklok designs and builds automated packaging systems.

Financial Security, IB's property and casualty insurance holding company, reported 1978 earnings of $9 million (2.99 a share), up 43 percent from $6.3 million ($2.10) in 1977. Forth-quarter profits declined, because of increased claims and higher losses, to $893,000 (80 cents) from $2.2 million (74 cents).

Smithfield Foods Inc., a Virginia meat packing company, reported higher earnings last year. From continuing operations, smithfield profits were $3.9 million ($1.56) compared with $1.6 million (61 cents). Overall net income, including tax credits related to previous operations and income from discontinued business, was $6.6 million ($2.66) compared with $2.2 million (84 cents). Sales rose to $171 million from $139 million.

Federal Realty Investment Trust, a Chevy Chase company, reported a decline of 6 percent in net income for 1978. Earnings were $1.65 million ($1.14 a share) compared with $1.76 million ($1.29), as cash flow increased 2 percent to $1.96 million and gross income rose 22 percent to $8.1 million.

Managing trustees of Federal Realty said the lower earnings reflected higher no-cash depreciation deductions and higher interest costs. The trust, which owns 13 shopping centers and 5 apartment developments, reported a 31 percent gain in assets to $39 million.