Descriptiv escriptive e List of Selected Sweet Potato Varieties for Lowland Conditions NARI Extension Series Booklet No. 2 March 2001 NATIONAL AGRICULTURAL RESEARCH INSTITUTE
THE INSTITUTE The National Agricultural Research Institute (NARI) was established by an Act of National Parliament of Papua New Guinea in July 1996 as a publicly funded, statutory research organisation, to conduct applied and development oriented research on food crops, alternative food and cash crops, livestock and resource management issues. Besides applied and adaptive research, NARI is responsible for providing authoritative technical, analytical and diagnostic services and up-to-date information to the entire agriculture sector in PNG. The major targets are the smallholder semi-commercial farmers in the country. The mission of NARI is to contribute, through applied research and technical services, to the development of the agriculture sector and realisation of the national goals by identifying, adapting and transferring agricultural technologies and information, so as to: Enhance the productivity, efficiency and sustainability of the smallholder agriculture, and Improve farmer income, food security and the welfare of Papua New Guineans and the Nation. The material presented in this Extension Booklet is based on the best information available at the time of printing, March 2001. This leaflet was written by Elick Guaf, John Demerua, Paul Van Wijmeersch, Michael Kalamen and Christopher Tep of NARI Wet Lowlands Islands Programme, Keravat, East New Britain. Cover Photo: Sweet Potato Field Germplasm Collection at Aiyura, NARI Main Highlands Programme, Kainantu, EasternHighlands.
Other NARI Publications 1. NARI Corporate Plan 2000-2004. 2. Proceedings of the NARI Poultry Workshop: NARI Proceedings Series, Proceedings No.1, March 2000. 3. Prospects for Vanilla Development in Papua New Guinea. Proceedings of a Farmer/Researcher/ Marketer Workshop: NARI Proceeding Series, Proceedings No. 2, September 2000. 4. Focus for Agricultural Research in Papua New Guinea: Paper presented at the Agriculture Policy and Srategies Conference 2000 on Reforming and Reconstructing the Agricultural Sector at the local Level: NARI Conference Paper Series, Conference Paper No.1, December 2000. 5. How to Produce Home-made Pesticides: NARI Extension Series, Booklet No.1, February 2001.
FORWARD This booklet presents achievements of the project Selection, Trial and Dissemination of Sweet Potato Cultivars, which was funded by the European Union through the Pacific Regional Agricultural Programme (PRAP). The work was initially implemented by the Department of Agriculture and Livestock, and later became the responsibility of the National Agricultural Research Institute (which assumed responsibility for agricultural research in 1997). This information has been re-written for publication with assistance from the Australian Agency for International Development project (Australian Contribution to the National Agricultural Research System) in 2000. i
Descriptive List of Selected Sweet Potato Varieties for Lowland Conditions Introduction The European Union funded Pacific Regional Agricultural Programme (PRAP) project Selection, Trial and Dissemination of Sweet Potato Cultivars has evaluated the performance of different Papua New Guinea and introduced sweet potato cultivars, for cultivation in the lowlands of PNG and other Pacific countries. The evaluation was based on the characteristics of: yield; plant vigour; susceptibility to rat damage and scab disease; tuber cracking; ease of harvest; rotting; tuber shape; market appeal; dry matter content; and, very importantly, taste. This report presents information about the varieties which had been selected for lowlands cultivation as of December 1998. First class varieties are those with the most desirable combination of characteristics. Second class varieties have some very good and some negative characteristics, and thus are recommended for special purposes or breeding programs. The second class selected varieties consist of two groups: 1. High yielding varieties, which have some negative characteristics such as poor shape or cracking. 2. Moderately yielding varieties, which have desirable characteristics such as a good shape or a deep orange flesh colour. Each variety listed is described in terms of six characteristics, as defined below. I. Tuber shape (see figure 1): 1 - Elongate 2 - Fusiform 3 - Oval 4 - Proximal end narrow, distal broad 5 - Proximal end broad, distal narrow 6 - Rectangular in outline 1
II. III. Tuber skin colour: 1 - White or creamy 2 - Yellow 3 - Orange 4 - Brown 5 - Red 6 - Purple 7 - Pink (often pale) 8 - White and purple Tuber flesh colour: 1 - White 2 - Yellow 3 - Orange 4 - Purple IV. Time to maturity (in months) The time to maturity depends on the weather conditions during the growing period. Some varieties, however, will give a good yield earlier than others. Of those varieties, some must be harvested early to avoid rotting or rat and weevil damage, or both, while others can be left in the soil without deterioration of the tubers. V. Texture Soft does not mean that the variety is watery, a characteristic which is correlated with a low dry matter content. The variety is just less than others after boiling. VI. Sweetness All sweet potato varieties are sweet compared to, e.g., yam. Some varieties, however, are less sweet than others and are referred to in this report as slightly sweet or not sweet. 2
AVAILABILITY OF PLANTING MATERIAL Planting material of most of the selected varieties is readily available from the NARI Wet Lowlands Islands Programme (LAES), Keravat, East New Britain Province. For practical reasons only a small number of cuttings will be supplied, for example 30 cuttings of each requested variety. Further multiplication of the varieties is expected to be done by the requesting farmer or institution. People around the Gazelle Peninsula can come to LAES to get planting material, but, please give notice in advance. For people outside the Gazelle Peninsula, freight costs will have to be paid. It is planned to establish multiplication plots of the selected varieties at all NARI Research Stations and on as many as possible DPI stations. Interested farmers and institutions are recommended to choose which type of variety they would like to receive from the descriptive list and send their request to the address below: The Research Programme Leader NARI Wet Lowlands Islands Programme LAES, Keravat P.O. Box 204 KOKOPO East New Britain Phone: (675) 983 9145 Fax: (675) 983 9129 Email: narilli@datec.com.pg 3
Figure 1: Sweet potato tuber shape (Source: Yen, 1974). 1. Elongate 2. Fusiform 4
Figure 1: Sweet potato tuber shape (continued from page 4). 3. Oval 5. Proximal end broad, distal narrow 4. Proximal end narrow, distal broad 6. Rectangular 5
SHAPE TASTE B 11 white white 4.5 not sweet BEERWAH GOLD 2nd class (Australia) oval orange orange 5 intermediate intermediate sweet BOROBUDUR 2nd class (Indonesia) BUB 1 orange orange 5 sweet purple white 5 intermediate sweet CRISIS proximal end broad, white white 4.5 sweet distal end narrow can be later DOY 2 fusiform purple white 5 intermediate slightly sweet 6
SHAPE TASTE DOY 3 purple white 4.5 very sweet taste very well appreciated K 9 proximal end broad, pink white 4.5 sweet taste distal end narrow well appreciated K 130 (= L131 & Halasika) 2nd class (PNG/Tonga) elongate purple white 5 not sweet K 142 white orange 5 intermediate slightly sweet with yellow patches KAV 11 fusiform white white 5 intermediate sweet (thick skin) 7
SHAPE TASTE KAV 34 white white 4 to 4.5 soft sweet KAV 57 orange orange 5 soft not sweet KAV 61 fusiform white yellow with orange patches 5 intermediate sweet KAV 79 rectangular pink white 5 intermediate sweet KEKORI 2 nd class white yellow at least 5 sweet 8
SHAPE TASTE KINABAKAP (Philippines) purple white 5 sweet L 9 fusiform white white 4.5 intermediate sweet can be later L 16 L 19 proximal end broad, distal end narrow white white 5 intermediate not sweet white white 5 soft sweet L 22 purple white 4.5 sweet (= KAV 39) can be later 2nd class L 43 pink orange with yellow patches 4 to 4.5 not sweet 9
SHAPE TASTE L 46 purple white 5 intermediate slightly sweet L 50 2nd class purple white 5 not sweet L 135 proximal broad, distal white orange 4.5 soft slightly sweet end narrow L 188 2nd class L 318 purple white 5 sweet purple orange 5 slightly soft slightly sweet L 329 pink white 4.5 slightly sweet can be later 10
SHAPE TASTE L 676 fusiform purple white 5 intermediate slightly sweet L 781 proximal end broad, distal end narrow purple white 5 intermediate slightly sweet L 788 oval orange orange 4.5 soft slightly sweet L 879 purple white 5 intermediate slightly sweet L 942 proximal end broad, white orange 4.5 slightly sweet distal end narrow with can be later yellow patches L 949 proximal end broad, distal end narrow white orange 5 intermediate slightly sweet 11
SHAPE TASTE L 997 pink white 5 intermediate sweet MARKHAM PNG 415 2nd class fusiform white purple with white patches at least 5 sweet MAS 1 proximal end broad, white orange 5 slightly sweet distal end narrow with yellow patches MAS 2 purple white & 4.5 soft sweet purple can be later NGI 24 proximal end broad, purple white 4.5 intermediate slightly sweet distal end narrow 12
SHAPE TASTE NUG 2 fusiform white yellow 5 not sweet NUG 5 dark purple purple with white patches 5 or later not sweet PNG 11 fusiform white white 5 not sweet PNG 75 PNG 506 PNG 692 proximal end broad, distal end narrow purple white 5 intermediate sweet white yellow 5 sweet pink white 5 intermediate not sweet 13
SHAPE TASTE PNG 1164 fusiform white white 5 not sweet POI 6 fusiform white (thick skin) yellow 4.5 can be later intermediate slightly sweet POI 13 fusiform white white 4.5 sweet can be later RAB 7 oval purple white at least 5 sweet RAB 24 proximal end narrow, distal end broad purple white at least 5 intermediate slightly sweet RAB 35 fusiform white white 5 soft sweet 14
SHAPE TASTE RAB 36 purple orange with white patches 5 not sweet at harvest (if left 3 days it will be sweet) RAB 37 oval purple white with patches of orange and purple 5 intermediate sweet, it tastes like a mixture of two varieties, the orange part is softer RAB 38 purple white 5 in dry season, sweet late in wet season RAB 43 purple white 4.5 not sweet can be later RAB 44 fusiform pink orange 4 to 4.5 soft not sweet 15
SHAPE TASTE RAB 45 purple orange 5 soft not sweet RAB 46 SATU (87046-4) (Tonga) fusiform white yellow orange 5 soft not sweet purple/ white 5 sweet brown SI 11 elongate pink white 4.5 soft not sweet can be later (Solomon Is.) SI 41 fusiform white white 4.5 sweet (Solomon Is.) SI 67 (Solomon Is.) white white 5 sweet 16
Copies can be obtained from: The Publications Section Sir Alkan Tololo Research Centre National Agricultural Research Institute Kana Aburu Haus P.O. Box 4415 LAE 411, Morobe Province Papua New Guinea Phone: (675) 475 1444/475 1445 Facsimile: (675) 475 1450 Email: narihq@nari.org.pg Website: www.nari.org.pg