ARGENTINE MAIZE, SOYBEAN FORECASTS FALL Argentine grain growers reduced their estimates for maize and soybean production in the current harvest in the week to yesterday, trade sources said. Soybean production for 1986/87 is now estimated to reach between 7.7 and eight mln tonnes, versus 7.8 to 8.2 mln tonnes estimated a week ago and eight to 8.4 mln tonnes estimated in mid-February. But even the lowest of those estimates would be 8.5 to 12.7 pct greater than last year's total of 7.1 mln tonnes, according to official figures, and would be a new record. The total area planted with soybeans for this harvest was a record 3.7 to 3.8 mln hectares and increased 10.8 to 13.8 pct compared to the 3.3 mln hectares planted last year. The change in yield estimates is due to very high temperatures and inadequate rainfall since early in the year in the soybean-producing belt of southern Cordoba and Santa Fe and northern Buenos Aires province. The heat and lack of rain combined to leave many soybean pods empty, especially in Cordoba. Intense rains in recent weeks did not affect crops, since rainfall was slight in most main soybean-producing areas. Rains in the week to yesterday were isolated and weak in Buenos Aires province, totalling between one and 10 mm. There was no recorded rain in other grain-producing provinces. With clear skies and seasonable temperatures, fields were able to dry in areas that had received heavy rains in recent weeks, allowing growers to accelerate the pace of maize, sunflower and sorghum harvesting. Crops were considered in generally good condition, though it is still too early to judge whether the intense rains of recent weeks caused any long-term damage. The maize harvest advanced to between 20 and 22 pct of the total area planted, compared to 13 to 15 pct a week ago. Total area planted with maize for this harvest stood at 3.58 to 3.78 mln hectares, down two to seven pct from the 3.85 mln hectares planted in the previous harvest. Total production for the current maize harvest is expected to reach between 9.9 and 10.1 mln tonnes, versus 10 to 10.2 mln tonnes estimated a week ago. The new figure is 21.1 to 22.7 pct lower than the 12.8 mln tonnes produced in the last harvest, according to official figures. The sunflower harvest advanced to between 20 and 23 pct of total planted area, versus 15 to 18 pct a week ago. Total area planted with sunflower for this harvest was two to 2.2 mln hectares, or 29.9 to 36.3 pct lower than the record 3.14 mln hectares planted in the 1985/86 harvest. The current harvest's volume was again expected to be between 2.3 and 2.6 mln tonnes, or 34.1 to 41.5 pct lower than last harvest's record 4.1 mln tonnes. Yields varied widely from area to area, and growers feared that heavy rains in recent weeks may have taken their toll on crops and, consequently, on total production volume. The sorghum harvest reached between nine and 11 pct of total planted area, compared to four to six pct a week ago. Total area planted with sorghum stood at between 1.2 and 1.3 mln hectares, or 10.3 to 15.2 pct lower than the 1.4 mln hectares planted in the previous harvest. Estimates for total sorghum production this harvest remained at 3.2 to 3.5 mln tonnes again this week, or 16.7 to 22 pct lower than last harvest's total volume of 4.1 to 4.2 mln tonnes.