The list of made-in-Moscow weapons that have become casualties of the fighting in Lebanon appears to be growing.

Yesterday, Israeli Defense Minister Ariel Sharon announced that new Israeli-made Merkava tanks had knocked out nine of the Soviet Union's latest T72 medium tanks during battles with Syrian forces.

The T72 is the latest Soviet main battle tank. Several thousand are in service with Soviet forces and smaller numbers are in service with Soviet allies in Eastern Europe and other regions, including about 400 in the Syrian army.

Sharon claimed that the battle showed the supremacy of the Merkava, which is equipped with an American 105-mm. gun, "over what had been thought of as the best tank in existence," meaning the T72.

American specialists said it was far too early to evaluate such a claim because the circumstances of the battle were not known. The extent of training of the Syrian crews and of Israeli losses also were not known here.

Nevertheless, this is believed to be the first combat test of the T72, and specialists said analysis of the results could be especially important for NATO forces. The T72 is supposed to have improved armor to protect it.

The loss of these tanks just before the cease-fire between Israel and Syria went into effect yesterday could become a prize for western intelligence agencies if the Israelis manage to recover the vehicles and let American specialists inspect them. The Israelis captured hundreds of older Soviet T62 tanks during the 1973 Middle East war, and they provided valuable information for allies.

Soviet-built Mig 21 and Mig 23 jet fighters and SAM2 and SAM6 surface-to-air missiles used by the Syrians also were knocked out in large numbers, according to Israeli reports that are generally confirmed here, during the six days of fighting.