Weed seed populations in rubber and oil palm plantations with legume cover crops
B.S. Ismail, A. Tasrif, S.S. SastroutomoA and A. Latiff, Botany Department, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor DE, Malaysia.
A CAB-International, Kuala Lumpur, Malaysia.
Summary
The seed populations in the top 10 cm soil of 0–6, 7–20 and more than 20-year old plantations of rubber and 0–3, 4–20 and more than 20-year old plantations of oil palm grown with legume cover crops were studied by physical extraction and germination. Seeds belonging to 21 and 25 species were recorded in rubber and oil palm plantations respectively, with Asystasia gangetica (L.) T. Anders., Cleome rutidosperma DC., Borreria alata DC. and Paspalum conjugatum Berg. being most abundant in both plantations and accounting for more than 80% of the total weed seeds.
An average of 3298 and 3262 seeds m-2 were recorded in the soil of rubber and oil palm plantations, respectively. Total seed number declined with increasing maturity of plantations. The monthly emergence of A. gangetica, Ageratum conyzoides L., Oldenlandia herbacea L., Cyperus rotundus L., P. conjugatum and C. rutidosperma are presented. Most species emerged during the first month after planting.
Plant Protection Quarterly (1995) 10 (1) 20-23.