Pengaruh Saat Tanam dan Populasi Jagung Terhadap Pertumbuhan dan Hasil Tanaman Dalam Sistem Tumpanggilir Kedelai Dan Jagung

The research to study the effect of planting dates and maize population on
Growth and yield in relay cropping between soybean and maize have been
conducted at ATRD Gadjah Mada University during September 1997-February
1998.
Relay cropping system has been evaluated using 3 x 3 + 2 monoculture
treatments arranged in Randomized Complete Block Design with 3 replications.
Soybean and maize were planted in Additive Series System. The first factor was
maize planting dates with 3 levels, i.e.:0, 30, and 50 days after soybean planting.
The second factor was maize populations with 3 levels, i.e: 25,50, and 75 % from
optimal population in monoculture. Untreatment plant was soybean and maize
monoculture with recommendation population.
The results showed that growth and yield of soybean were not significantly
different, except on plant height and grain yield per hectare but were not
significantly different on maize population. Growth and yield of soybean in relay
cropping system were not significantly different with monoculture. The higher yield
was found treatment of 0 day after soybean and population on 50 %. Relay
cropping system was the best system compared to monoculture when the land
equivalent ratio was greater than 1.
Key word : planting dates, population, relay cropping, soybean, maize