IPNI SEAP Staff Publication List

2011

Donough, C.R., T. Oberthur, J. Cock, Rahmadsyah, A. Gatot, I. Kooseni, L. Ahmad, D. Tenri, C. Witt and T.H. Fairhurst. 2011.
Successful yield intensification with Best Management Practices (BMP) for oil palm at six plantation locations representing major growing environments of Southeast Asia.
Proceedings of the Malaysian International Palm Oil Congress (PIPOC): Agriculture, Biotechnology, and Sustainability Conference, Malaysian Palm Oil Board (MPOB), Ministry of Plantation Industries and Commodities, Kuala Lumpur, Malaysia, 15-17 November 2011. Pages 464-469.
Abstract: The world population is expected to increase to more than 9 billion in 2050. Most of these people will be city dwellers (Clay, 2011). A larger population coupled with increased disposable incomes and associated change in diet, with greater demand for processed food and animal products and biofuels, indicates the need to increase total agricultural production in the coming decades (FAO, 2006). From 1961 to 2005 most of the increase in agricultural production was due to increased yield and cropping intensity, with just 9% due to increased land area (Bruinsma, 2009). The trend for limited increases in land area devoted to agriculture are likely to continue, with the major increases in total production being from increased productivity (Bruinsma, 2009). However, there is considerable evidence that yields are stagnating in many crops (Fischer et al. 2009), Ramankutty, 2010; Byerlee & Deininger, 2010; Kushairi, 2010), including oil palm (Elaeis guineensis Jacq.) the most important source of vegetable oils (Fry, 2010). Most increases in palm oil production over the past fifty years have been due increases in area planted to oil palm, and there is concern exists about how to increase productivity to meet future requirements (Corley, 2009).

Gerendas, J., C. Donough and T. Oberthür. 2011.
Function and nutrient status of Sulphur in oil palm in Indonesia.
Oral presentation at Tropentag: Development on the Margin, Bonn, Germany, 5-7 October 2011.
Abstract: Sulphur (S) is indispensable for plant growth as S is a constituent of proteins, co-factors and in the form of sulphate esters a structural component of membranes. In recent decades the use of more concentrated straight and multi-nutrient fertilisers has led to a reduced S input from fertilisers in many regions of the world. Other important S inputs for agro-ecosystems, organic fertilisers and depositions from industrial pollution, are either of limited significance or not available. In oil palm (OP) S has not been considered in nutrient management to any large extent, and in Indonesia S-free fertiliser regimes, consisting of urea, rock phosphate, KCl and dolomite, are frequently used. In addition, S losses by leaching are naturally high in the humid tropics suitable for OP cultivation. Hence, there is a potential risk of S supply being insufficient, but data that allow assessing the S status were not available. In the course of a BMP (Best Management Practise) project initiated by IPNI SEA in July 2006 comprising of 30 commercial-size blocks in six locations in Sumatra and Kalimantan (three sites each) the leaf nutrient status was assessed by analyses of frond #17. A decline in the S status of the blocks receiving a typical fertiliser management (estate practise) was apparent at all six sites. In 2009 average leaf S levels of only 0.13% (range: 0.11 - 14 %) were observed. It is argued that published critical S value (0.20%) might be inflated. Therefore, the N/S ratio, frequently considered a more reliable indicator of the S status, was also evaluated. On average a ratio of 19/1 (range: 16.8 - 22.8 to 1) was obtained, strongly suggesting a S deficiency situation. Assuming a critical N/S ratio of 15/1 and a critical and adequate N concentration of 2.3 and 2.5 %, respectively, adjusted critical S concentrations of 0.15 and 0.17% may be proposed. The S status of oil palm reported here is even below these adjusted critical levels. Experiments are currently being initiated to (1) re-evaluate the critical S concentration and (2) assess the yield response to S supply at commercial block scale.

Gerendas, J., C.R. Donough, T. Oberthür, A. Lubis, K. Indrasuara, T. Dolong, G. Abdurrohim and Rahmadsyah. 2011.
Sulphur nutrition of oil palm in Indonesia - The neglected macronutrient.
Poster presented at the Malaysian International Palm Oil Congress (PIPOC): Agriculture, Biotechnology, and Sustainability Conference, Malaysian Palm Oil Board (MPOB), Ministry of Plantation Industries and Commodities, Kuala Lumpur, Malaysia, 15-17 November 2011.
Abstract: The macronutrient sulphur (S) is a component of S-containing amino acids, and therefore essential for protein formation. Sulphur is also essentially required for oil synthesis. The S status of oil palm (OP) has not received much attention as it was assumed that the S requirement is met by natural deposition and application of S-containing fertilizers. However, in oil palm plantations in Indonesia S-free fertilizer regimes, based on urea, KCl, dolomite, and rock phosphate, have been used widely during the last decades. Thus, there is a potential risk of S supply being insufficient, but data allowing assessment of the S status were not available.

Gerendas, J., C.R. Donough, T. Oberthür, Rahmadsyah, Gatot Abdurrohim, Kooseni Indrasuara, Ahmad Lubis and Tenri Dolong. 2011.
Sulphur nutrition of oil palm in Indonesia - The neglected macronutrient.
Re-produced in Oil Palm Bulletin, 67:5-10.
Abstract: Sulphur (S) has received limited attention by researchers, agronomists and planters involved in oil palm cultivation, despite the fact that the requirement at tissue level – as indicated by published critical concentrations in Frond #17 – is the same for S and magnesium (Mg) (0.2%). The continuous trend toward S-free fertilisers (urea, rock phosphate, KCl, dolomite) in Indonesia, together with high leaching rates of sulphate, have putatively reduced the S availability in many oil palm estates. However, this has rarely been addressed up to now. The BMP (Best Management Practice) project on SEA programme carried out at six sites, which are representatives for current management practices in oil palm cultivation, revealed a very low S status throughout, as determined by the S concentration in Frond #17, with mean values of 0.12% - 0.13% S. After evaluating available literature a downward adjustment of the published critical S 0.15% seems appropriate. Considering the more - 2.8%, an adequate range for S of 0.16% - 0.19% is proposed. The results clearly indicate a very low S status even when evaluated using these adjusted critical S concentrations. Researchers, agronomists and planters are encouraged to pay more attention to the S supply and to the determination of S in foliar analysis. Until the proposed critical S concentrations are supported through experimental data, it is recommended that S-containing fertilisers S-containing fertilisers could be used. Kieserite (MgSO4. H2O) seems particularly suitable due to its market availability and because both macronutrient elements contained are required in similar amounts by oil palm.

IPNI. 2011.
Planters' Diary 2011.
International Plant Nutrition Institute, Penang, Malaysia.

Laderach, P., T. Oberthur, S. Cook, M. Eztrada Iza, J.A. Pohlan, M. Fisher and R. Rosales-Lechuga. 2011.
Systematic agronomic farm management for improved coffee quality.
Field Crops Research, Vol 120, page 321-320.
Abstract: There is growing interest of international markets in differentiated agricultural products from the tropics. Coffee is a tropical crop of relatively high quality, whose value is increasing as consumer demand in developed countries for specialty coffee. Smallholders in emerging markets can benefit by capitalizing on the natural resource variability in their production system and from the knowledge that they have about this variability. The objective of this paper is to illustrate the benefits of systematically targeting management practices by coffee growers to improve attributes of their product. Data from case studies in Colombia and Mexico show statistically significant differences in beverage quality of coffees grown under different production conditions such as slope aspect, varieties, times of harvest, and shade levels. Possible intervention options can be selected by growers in terms of their ease of implementation, the likely improvement of quality that they achieve and the resource intensiveness they require. The conclusion is that optimum management is site specific so that it is not possible to make any blanket recommendations. Using continuous management cycles of implementation, observation, interpretation and evaluation the site specificity provides growers an opportunity to improve management over time to produce a higher quality product.

Nelson, P., M. Webb, S. Berthelsen, G. Curry, D. Yinil, C. Fidelis, M. Fisher and T. Oberthür. 2011.
Nutritional status of cocoa in Papua New Guinea.
Better Crops with Plant Food, Vol 95, Issue 2, page 18-20.
Abstract: Leaf and soil nutrient status was surveyed at 63 cocoa sites in Papua New Guinea (PNG) to determine if productivity is nutrient limited and how these limitations might be overcome. Nitrogen and Fe were deficient in 89% of the sites and P was deficient in about 25%. Management of cocoa in PNG must improve dramatically for the industry to prosper. Successful management schemes should consider a full systems context due to the complexity of socio-economic-agronomic factors. Improved nutrient management will require development of tools directed towards better foliar analysis.

Oberthür, T. and C.R. Donough. 2011.
Sustainable intensification with Best Management Practices (BMP): Oil Palm in Southeast Asia.
Oral presentation at the Malaysian International Palm Oil Congress (PIPOC): Agriculture, Biotechnology, and Sustainability Conference, Malaysian Palm Oil Board (MPOB), Ministry of Plantation Industries and Commodities, Kuala Lumpur, Malaysia, 15-17 November 2011.