The worst drought in over five decades is damaging crops and driving the rally in corn, grains and agriculture ETFs.

The iPath Grains ETN (NYSEArca: JJG) was the week’s top performer in unleveraged exchange traded products with a 10% gain. [Corn ETF Rallies 35% in a Month on Record Prices]

Meanwhile, ETFs pegged to the major U.S. indices were on track for slight weekly gains in afternoon trading Friday. The S&P 500 added 0.6%, the Dow rose 0.4% and the Nasdaq Composite climbed 0.9%. [Corn ETF Surges]

Yet the Dow shed more than more than 100 points Friday afternoon on Eurozone debt fears focused on Spain. Spanish bond yields rose to euro-era highs.

Europe jitters faded earlier in the week and the S&P moved higher, “but it looks as if Europe is taking center stage again, with Spain as the main act,” said Quincy Krosby, market strategist at Prudential Financial, in a Reuters report.

An ETF tracking Spain was this week’s worst performer among unleveraged funds with a decline of more than 7%.

In sector ETFs, SPDR KBW Bank ETF (NYSEArca: KBE) slipped about 3% on disappointing earnings.

Conversely, agriculture-related ETFs led the way on soaring temperatures in the U.S. Elsewhere in commodities, oil ETFs were strong as crude prices climbed back above $90 a barrel.

The top unleveraged ETFs this week were iPath Grains ETN, iPath Agriculture ETN (NYSEArca: JJA) and U.S. Natural Gas Fund (NYSEArca: UNG). They were up more than 6% for the week in afternoon trade Friday.

The bottom unleveraged ETFs this week were iShares MSCI Spain, iShares MSCI Italy (NYSEArca: EWI) and Guggenheim China Small Cap (NYSEArca: HAO) with losses of over 4%.

In next week’s economic data, look for reports on home prices and sales, durable goods orders and consumer sentiment. Investors will also get their first look at second-quarter GDP on Friday.

iPath Grains ETN