Oil palm is cultivated by agro-industries and smallholders for vegetable oil production. Good farm management practices with balanced soil and plant macronutrients are needed to attain optimum yields. Smallholder oil ...Oil palm is cultivated by agro-industries and smallholders for vegetable oil production. Good farm management practices with balanced soil and plant macronutrients are needed to attain optimum yields. Smallholder oil palm farmers of Dibombari Sub-Division, Cameroon, suffer from low on farm yields which could emanate from the agronomic practices implemented, which also has an influence on the soil and plant macronutrient status. This study provides information on the agronomic practices, soil and plant macronutrients status in smallholder oil palm fields. Structured questionnaires were administered to 200 farmers to collect data on their agronomic practices, using a stratified random sampling design. Soil and plants were sampled from plantations of different age groups (control, >0 - 4 years, >4 - 8 years and >8 - 15 years’ plantations) in four locations of the Sub-Division (i.e. Dibombari-central, Bonamateke, Bomono and Nkapa) using a randomized complete block design. Data collected, was analyzed using descriptive and inferential statistics. The results showed that 65% of farmers planted Tenera variety, with majority of them below the standards for weeding (81%), fertilizer use (100%), pruning (62%), pest/disease control (90.5%) and harvesting (96%) practices. Soil macronutrients were low across the different plantations except P which was optimal at >0 - 4 years and >4 - 8 years’ plantations but low at >8 - 15 years’ plantation. Similarly, for plant macronutrients, N and P were optimal across the different plantations, while K and Mg were optimal at >0 - 4 years’ plantation but low at >4 - 8 years and >8 - 15 years’ plantations. Thus, agronomic practices and macronutrient status of soil and plants were below standards in smallholder oil palm plantations of Dibombari, leading to low yields of fresh fruit bunches.展开更多
提高氮肥利用效率是当前小麦生产中重要的研究方向之一。本研究以光明麦1号为试验品种,利用两年的田间试验结果,采用二次正交旋转组合设计建立回归模型,分析稻茬小麦的氮肥当季表观利用率（utilization rate of nitrogen fertilizer,NU...提高氮肥利用效率是当前小麦生产中重要的研究方向之一。本研究以光明麦1号为试验品种,利用两年的田间试验结果,采用二次正交旋转组合设计建立回归模型,分析稻茬小麦的氮肥当季表观利用率（utilization rate of nitrogen fertilizer,NUR）受播期、密度、施氮量组合的调控效应。结果表明,对小麦NUR效应表现为氮肥〉播期〉密度。在试验条件下,实现高产和高NUR目标,三因素有多种组合模式,其中播期10月28日至11月2日＋密度160~180万株hm–2＋施氮量200 kg hm–2的组合,其产量为6800~7200 kg hm–2,NUR大于42.0%（最大值为44.8%）,可靠度达到95%;播期10月21日至27日＋密度120~150万株hm–2＋施氮量190~225 kg hm–2组合,其产量为6200~7000 kg hm–2,NUR达41.0%以上;播期11月3日至11日＋密度210~240万株hm–2＋施氮量190~210 kg hm–2组合,其产量为5900~7250 kg hm–2,NUR达39.0%以上。展开更多
文摘Oil palm is cultivated by agro-industries and smallholders for vegetable oil production. Good farm management practices with balanced soil and plant macronutrients are needed to attain optimum yields. Smallholder oil palm farmers of Dibombari Sub-Division, Cameroon, suffer from low on farm yields which could emanate from the agronomic practices implemented, which also has an influence on the soil and plant macronutrient status. This study provides information on the agronomic practices, soil and plant macronutrients status in smallholder oil palm fields. Structured questionnaires were administered to 200 farmers to collect data on their agronomic practices, using a stratified random sampling design. Soil and plants were sampled from plantations of different age groups (control, >0 - 4 years, >4 - 8 years and >8 - 15 years’ plantations) in four locations of the Sub-Division (i.e. Dibombari-central, Bonamateke, Bomono and Nkapa) using a randomized complete block design. Data collected, was analyzed using descriptive and inferential statistics. The results showed that 65% of farmers planted Tenera variety, with majority of them below the standards for weeding (81%), fertilizer use (100%), pruning (62%), pest/disease control (90.5%) and harvesting (96%) practices. Soil macronutrients were low across the different plantations except P which was optimal at >0 - 4 years and >4 - 8 years’ plantations but low at >8 - 15 years’ plantation. Similarly, for plant macronutrients, N and P were optimal across the different plantations, while K and Mg were optimal at >0 - 4 years’ plantation but low at >4 - 8 years and >8 - 15 years’ plantations. Thus, agronomic practices and macronutrient status of soil and plants were below standards in smallholder oil palm plantations of Dibombari, leading to low yields of fresh fruit bunches.
文摘提高氮肥利用效率是当前小麦生产中重要的研究方向之一。本研究以光明麦1号为试验品种,利用两年的田间试验结果,采用二次正交旋转组合设计建立回归模型,分析稻茬小麦的氮肥当季表观利用率（utilization rate of nitrogen fertilizer,NUR）受播期、密度、施氮量组合的调控效应。结果表明,对小麦NUR效应表现为氮肥〉播期〉密度。在试验条件下,实现高产和高NUR目标,三因素有多种组合模式,其中播期10月28日至11月2日＋密度160~180万株hm–2＋施氮量200 kg hm–2的组合,其产量为6800~7200 kg hm–2,NUR大于42.0%（最大值为44.8%）,可靠度达到95%;播期10月21日至27日＋密度120~150万株hm–2＋施氮量190~225 kg hm–2组合,其产量为6200~7000 kg hm–2,NUR达41.0%以上;播期11月3日至11日＋密度210~240万株hm–2＋施氮量190~210 kg hm–2组合,其产量为5900~7250 kg hm–2,NUR达39.0%以上。
