Seed yam production from whole tubers versus minisetts

Abstract

Yam (Dioscorea rotundata Poir.) is a major staple and cash crop for millions of households in West Africa, where about 93% of the world crop is produced. The tuber serves as food and seed. Depending on the size, seed tubers are often cut into setts, minisetts, or planted whole. An experiment was conducted to investigate the effects of using whole tubers versus minisetts to produce seed yams. Six treatments constituted combinations of whole tubers and minisetts, and three tuber-size classes, viz., 30-59 g, 60-89 g, and 90-120 g (averaged and referred to as 45 g, 75 g, and 105 g, respectively). The experiment was conducted as a randomized complete block design with three replications. Results showed that plants from whole tubers emerged from the soil faster and yielded 48% more than those from minisetts. The mean yield of 105 g minisetts (18.3 t/ha) was statistically similar to that of 45 g whole seed (17.9 t/ha). Using 45 g whole seed would save about 2 t/ha of the harvested crop for use as food instead of seed. So, planting small whole tubers is more profitable than minisetts and is recommended to yam growers.

Potential returns to yam research investment in sub-Saharan Africa and beyond

“…The results are consistent with Aighewi et al (2002) and Mignouna et al (2015) that indicated that quality seed yam unavailability constitutes the major limitation of yam production. Moreover, the BCRs of all the research options imply that investment in research and dissemination of these technologies is worthwhile and economically viable as the benefits greatly outweigh the costs as in agreement with many similar studies on ex ante impact assessment ( Akinola et al, 2009 ; Ayanwale et al, 2013 ; Kostandini et al, 2009 , 2011 ).…”

“…Adoption studies revealed cases of low or reverse adoption ( Morse, 2018 ; Nweke, 2016 ). Consequently, the YMT was modified by the YIIFSWA project into the adaptive YMT (AYMT) to address farmers’ complaints about the size of tubers produced while incorporating the use of available chemical treatments to lessen pest and disease pressure ( Aighewi et al, 2002 ). The project started using participatory approaches with an integrated training and visit model to disseminate the technique vigorously in yam producing countries of WA since its inception in 2012 to strengthen the yam seed system for quantity and quality assurance.…”

“…Its prominence as an arable crop is intricately linked to its substantial contribution to dietary protein and wide consumption especially in West Africa (WA) and the Caribbean as an important delicacy ( Asiedu and Sartie, 2010 ). Moreover, yam is a valued ceremonial and traditional crop playing important roles in the social ceremonies of WA region ( Aighewi et al, 2002 ). However, arguably, availability of and access to good-quality planting materials is the most severe problem militating against an increase in agricultural productivity ( Aighewi et al, 2015 ; Gildemacher et al, 2009 ; Poku et al, 2018 ).…”

“…However, arguably, availability of and access to good-quality planting materials is the most severe problem militating against an increase in agricultural productivity ( Aighewi et al, 2015 ; Gildemacher et al, 2009 ; Poku et al, 2018 ). This may be reflected in the multifaceted institutional, ecological, technical, and economic seed-related problems bedeviling the yam sector ( Aighewi et al, 2002 ). In fact, it has been posited that a considerable amount of production-related costs are usually connected with seed acquisition and use.…”

Genetic parameter estimation and selection in advanced breeding population of white Guinea yam

“…White Guinea yam (D. rotundata) is among the widely cultivated species that serve as a valuable source of food and income to over 300 million people in Africa (Alabi et al 2019). The global yam production is estimated at 73 million tons, with West Africa accounting for more than 93% of the total yam production (Aighewi et al 2020).…”