Growth, yield and yield components of peanut (Arachis hypogaea L.) and sorghum (Sorghum bicolor L. Moench) intercrop as influenced by row arrangement and sowing date [Philippines]

A field experiment was conducted at the UPLB [Philippines Univ., Los Banos, College, Laguna, Philippines] Central Experiment Station from February to June, 1987 to compare the growth, yield and yield components of peanut and sorghum grown as intercrops and under monoculture at different sowing dates and row arrangements: The three sowing dates were: a) peanut and sorghum planted at the same time at day one (T1), b) peanut planted 14 days before sorghum (T2) and c) peanut planted 14 days after planting sorghum (T3). The row arrangements were: a) one row of sorghum alternated with one row of peanut (S1:P1), b) one row of sorghum alternated with two rows of peanut (S1:P2), c) two rows of sorghum alternated with two rows of peanut (S2:P2), d) monoculture sorghum (S) and e) monoculture peanut (P). Peanut intercrops yielded less than those in monoculture. Shading by sorghum reduced the number of mature pods, leaves and root nodules but increased the height of peanut intercrops. The leaf area index, dry matter yield, relative leaf growth rate, leaf area ratio and crop growth rate of peanut intercrops were not affected by sorghum during the first seven weeks of growth. Sorghum monoculture yielded more than those in the intercrops due to the lower plant population in the latter. Delayed sowing of sorghum also resulted in low yields. The number of panicles per hill and the number of seeds per panicle at T2 were higher than those at T1, and T3. Harvest index of monoculture sorghum was low due to the unfavorable grain/stover ratio. Light transmission ratios in peanut and sorghum intercrops were lowest between 8 and 11 weeks and coincided with the pod filling stage of peanut. Land equivalent ratio (LER) of S2:P2 and S1:P1 row arrangements was 11% and 12% higher than the LER values of the monocultures, respectively. The S1:P1 row arrangement had 2% lower LER value than the monocultures. Based on the relative crowding coefficient and competitive ratio values sorghum out competed peanut in all row arrangements. However, the aggressivity values for sorghum and peanut in the S2:P2 row arrangements were the same