Seed priming makes good stands of maize the rule rather than the exception |
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Even when maize is irrigated, good crop stands are the exception rather than the rule for poor farmers. Yet, simply soaking seeds in water overnight and drying them before sowing as usual has been proven to increase yields in India, Pakistan, Zimbabwe and Nepal. In western India, where maize is often followed by another crop, priming means that maize can be harvested earlier. This gives farmers a chance to sow the second crop earlier and makes the most of the end of the rains. Hundreds of NGOs, farmers and researchers have asked for instructions on how to prime maize seed. Through these, priming maize seed has spread to Thailand, Myanmar, Kenya, Uganda, Ethiopia and Tanzania. Project Ref: PSP28:
Research Programmes: Plant Sciences Research Programme (PSP). Relevant Research Projects: R6395, R7189 (CPP), R7440, R7438
Research Outputs, Problems and Solutions: In marginal, rainfed areas, patchy plant stands often result from the failure of the crop to emerge quickly and uniformly. Farmers need a field full of plants to have any chance at all of getting a reasonable yield, yet good crop stands are often the exception rather than the rule for poor farmers. Yields of many crops, including maize, are reduced because not enough seeds germinate and the plants that eventually emerge do so slowly and are susceptible to drought, pests and diseases. Even in irrigated situations, maize yields can be compromised by poor stand establishment and slow early growth. On-farm seed priming is a simple, low-cost, low-risk technology that hastens germination and seedling emergence and promotes vigorous early growth so that transient resources (soil moisture, nitrogen, etc.) are captured and utilised. For maize, seed priming simply involves soaking seeds in water 'overnight', although optimum duration is around 16 hours, then drying maize seeds for 1-2 hours before sowing them in the normal fashion. Maize grown from primed seeds generally emerges earlier and in greater numbers, grows more vigorously, flowers and matures earlier and often yields better than that from non-primed seeds. Benefits due to priming extend beyond immediate yield increases in some circumstances. For instance, in western India where maize is often followed by another crop, earlier harvest of maize as a consequence of seed priming can facilitate earlier sowing, and hence higher yield, of the second crop. The technology was developed, tested, refined and promoted using a combination of in vitro, on-station and participatory action research with farmers in India, Pakistan and Zimbabwe during the period 1996-2006.
Rainfed- and irrigated maize in Asia and Africa. Seed priming has also been tested elsewhere in a range of other crops, the results of which are the subjects of other RIUP clusters - see:
Seed priming, including all work funded by PSP has been reviewed recently by Harris (2006)
There are a number of RNRRS outputs dealing with maize (see below) and all could be integrated fruitfully with maize seed priming:
How the outputs were validated: 'On-farm' seed priming of maize was developed, tested, refined and promoted during the period 1996-2006 using a combination of in vitro, on-station and participatory action research with farmers and researchers. In preliminary germination studies, Harris et al. (2002) showed that priming for 12 h significantly speeded up germination, without harming final germination, in 17 out of 18 maize cultivars from Zimbabwe and Murungu et al. (2005) showed that the relative beneficial effect of priming increased as moisture stress increased. Rashid et al. (2002) noted faster germination under both saline and non-saline conditions following priming in Pakistan. On-station studies in Gujarat, India (Harris et al, 1999) and in Zimbabwe (Chivasa et al. 2000) noted significantly faster emergence and taller, heavier seedlings from primed seeds. Finch-Savage et al. (2004) noted that priming increased the sensitivity of seeds to high temperatures but allowing primed seeds to dry for 1-2 h before sowing mitigated the negative effects of high temperatures and wet conditions. In pot studies with drying soils in Zimbabwe, Murungu et al. (2003) consistently improved emergence and early seedling growth across a range of soil moisture contents by priming seeds, but suggested caution when primed seed was sown in wet conditions where aeration was likely to be restricted. In Pakistan, in 14 on-station and on-farm trials in four districts (Banu, Mardan, Nowshera, Peshawar) of North West Frontier Province between 1998 and 2001, priming for 16-18 h gave increases in grain yield ranging from 17% to 76%. Farmers trials gave yield increases, using primed seed, of 40% (11 farmers) in 1999, 57% (15 farmers) in 2000 and 20% (6 farmers) in 2001. In no case was the result of priming worse than not priming (Harris et al. 2004). Many additional trials since 2000 (unpublished) have shown mean yield advantages of about 25% due to priming. Ninety-seven farmers tested maize seed priming in 1996-97 in tribal areas of Rajasthan, Gujarat and Madhya Pradesh, India (Harris et al. 1999). They reported in pre- and post-harvest focus group discussions that primed crops emerged 2-3 days earlier than non-primed ones and resulted in better, more uniform stands. Almost all farmers thought that primed crops grew more vigorously (and better competition with weeds was mentioned but not quantified), flowered and matured earlier and produced bigger cobs and higher yield. (Harris et al. 2001). Almost 100 % of farmers intended to continue priming in the future. Similar participatory exercises in semi-arid Zimbabwe concluded that primed maize primed emerged faster and more completely and flowered and produced cobs earlier (Harris et al. 2001). In farmers' fields in Mushagashe and Zimutu, priming increased grain yield by an average of 14 % consistently in three varieties grown in two contrasting years (Harris et al. 2002). Farmers also suggested that primed crops competed better with weeds. This could not be confirmed in on-station experiments to test this issue, but Harris (2006) has suggested a plausible mechanism to explain this effect. Jasi et al. (2000) calculated the economics of priming and concluded that, primarily because of its low cost, there were net benefits. Where the Outputs were Validated: Maize seed priming has been validated by farmers in:
Who are the Users? In Pakistan, priming maize with water was quickly adopted by farmers in the areas where it was tested and validated (see under "How the outputs were validated") although there has been no formal survey of how many. Experience suggests that, although farmers prime maize in rainfed and irrigated areas, they only do so where they consider soil moisture at sowing time to be suboptimum. Although uptake of maize priming by tribal farmers in Rajasthan, Gujarat and Madhya Pradesh, India was initially high (Harris et al. 1999) there have been no follow-up studies since 2000. The original collaborator, Gramin Vikas Trust, is still active in the area and could, with additional resources, quantify persistence and spread of the technology. Around 80% of the farmers testing maize priming in three districts (Gorkha, Myagdi and Palpa) of Nepal indicated a willingness to continue priming in future years but there has been no follow-up. The current political and security situation in Zimbabwe has prevented recent efforts to quantify the extent of any maize priming. Where the outputs have been used: Farmers are priming maize seeds in the North West Frontier Province of Pakistan, in Western India and in the mid-Hills of Nepal. It is likely that farmers in Zimbabwe are also priming maize seeds but it is not possible to confirm this. Farmers who have tested seed priming for upland rice in West Africa (Cameroon, Ghana, Nigeria) are also reported to have spontaneously begun priming maize. Scale of Current Use: Large numbers of farmers were involved in testing maize priming, as part of PSP-funded and targeted activities (see under "How the outputs were validated") and also as a consequence of observing the effect of priming in other crops (see under "Where the outputs have been used"). In addition, CAZS-NR has responded to many hundreds of requests for information on seed priming, many of them in relation to maize, from interested parties (researchers, NGOs, individual farmers). These responses have included, in addition to general information, reprints of papers etc, tailored protocols for participatory testing of priming specific to the crops of interest to the enquirer. We know, for instance, that maize priming has been tested, using such protocols, in Thailand, Myanmar, Kenya, Uganda, Ethiopia and Tanzania. Such enquiries are still being received and represent rapid spread of the technology. Policy and Institutional Structures, and Key Components for Success: Maize seed priming was developed and tested with farmers in Pakistan using the conventional institutional structures (primarily NWFPAU) for promotion and extension of agricultural information. However, although there is some commitment to adaptive research throughout the network of 16 research stations, there is still a reluctance to use participatory action research (PAR) widely. NGOs, such as GVT in India, generally have closer links to communities and are more willing to use PAR. A combination, often through collaboration, of the science-based philosophy of GOs and the social development approach of NGOs is the best way to promote outputs such as maize seed priming. Experience with other crops has shown that successful adoption has been achieved when priming is promoted as part of a 'package' and the 'integrated' approaches (IPM, ICM, ICNM, etc., often implemented through Farmer Field Schools or something similar) offer a good platform for such an approach. In addition, there is often great synergy between efforts to test and promote new varieties (which is generally a very popular exercise with farmers) and participatory testing of seed priming which can be done in tandem and with very little extra effort or resources. Lessons Learned and Uptake Pathways Promotion of Outputs: CAZS-NR maintains a website (www.seedpriming.org) and, as noted in "Scale of current use", responds to requests for information on seed priming on an ongoing basis. Information provided includes general information on priming, reprints of published papers and tailored protocols for participatory testing of priming specific to the nature of the enquiry. We have also distributed several thousand copies of two colour brochures (DFID/PSP 2001; 2006) to interested parties at international conferences and by post. For instance, 100 copies of DFID/PSP (2006) were sent recently to the Coordination Unit of the Agricultural Sector Support Programme, Uganda in response to a request via the internet. Seed priming has also been widely promoted during conference presentations around the world and at dedicated Technology Fairs (in Zimbabwe in December 2005 and in Uganda in February 2006). Maize seed priming is being promoted in the mid-Hills of Nepal by NGOs and the Hill Maize Programme with funding from the National Agricultural Research and Development Fund (Koirala and Ghimire, 2005). NWFPAU, its Outreach Directorate and the Department of Agricultural Extension continue to promote maize seed priming in Pakistan. Potential Barriers Preventing Adoption of Outputs: Potential institutional collaborators are generally unwilling to promote seed priming on evidence gathered elsewhere. This is not necessarily a bad thing because the act of testing with farmers engenders broad ownership of the technology. Seed priming is often viewed as being too 'simple' to extend on its own, so successful adoption has been achieved when priming is promoted as part of a 'package' and the 'integrated' approaches (IPM, ICM, ICNM, etc., often implemented through Farmer Field Schools or something similar) offer a good platform for such an approach. Holistic rural development programmes are particularly suited to these approaches. Lack of resources to support more PAR activities on a wider scale is a problem for countries where extension activities are not given a high priority. Nevertheless, the low-cost, low-risk nature of seed priming and its clear focus on resource-poor farmers make it a highly appropriate technology in countries with a commitment to reducing poverty. How to Overcome Barriers to Adoption of Outputs: Broader awareness is required of the advantages of maize seed priming and how it can be combined with other technologies to benefit resource-poor farmers. Institutionalisation of participatory approaches to agricultural and rural development would facilitate this as it would foster programmes that integrate diverse outputs to reduce poverty. Lessons Learned: Potential users (resource-poor maize farmers) must have two things; information on the potential benefits of maize seed priming and an opportunity to test it for themselves. Both are best supplied through close collaboration between farmers and extensionists working together to improve the whole farming system rather than isolated elements of it. Participatory action research (PAR) allows farmers to test priming for themselves, to see how it performs in a variety of situations (by observing their neighbours efforts) and to provide feedback (problems, possible solutions, improvements, etc) to all collaborators. PAR thus has a dual research/extension function. Poverty Impact Studies: No formal poverty impact studies have been done for maize seed priming. However, given that there are large, consistent yield benefits for almost no extra cost, the potential is high for generating additional agricultural income. Jasi et al. (2000) noted that there were economic benefits from priming maize in Zimbabwe, and Harris et al., (1999; 2001) reported a range of additional benefits from priming in India, including enhanced opportunities for migration because primed crops could be harvested earlier (those migrating earlier have a wider choice of employment). How the Poor have Benefited (including gender and other poverty groups): Resource-poor farmers, including men and women in Zimbabwe, India and Nepal but only men directly in Pakistan, have increased maize yields with little or no extra cost by priming seeds. Other benefits have also been reported, e.g. better stand establishment and so less gap-filling, less weed growth (and less weeding, usually done by women) in primed crops, an increased willingness by farmers to use fertiliser on primed crops, and earlier harvest leading to better following crops or the opportunity to migrate earlier. All these effects of priming maize increase income, reduce drudgery or increase economic opportunity. Direct and Indirect Environmental Benefits: Higher yields of maize crops per unit area as a result of priming seeds may reduce pressure on more marginal land. Increased straw production can reduce pressure on natural environments for feeding livestock. Adverse Environmental Impacts: No adverse environmental impacts are envisaged. Coping with the Effects of Climate Change, or Risk from Natural Disasters: Lack of choice in life is a defining characteristic of poverty. The direct (higher yield, increased food security and income) and indirect (less weeding, earlier harvest) benefits of maize seed priming all give farmers and their families more choices and lead to more resilient livelihood strategies. References Chivasa, W., Harris, D., Chiduza, C., Mashingaidze, A.B. and Nyamudeza, P. (2000). Determination of optimum on-farm seed priming time for maize (Zea mays L.) and sorghum (Sorghum bicolor [L.] Moench) for use to improve stand establishment in semi-arid agriculture. Tanzanian J. Agric. Sci. 3 (2): 103-112. DFID/PSP (2001). 'On-Farm' Seed Priming. A key technology to improve the livelihoods of resource-poor farmers in marginal environments. DFID/PSP information booklet, English language version. Centre for Arid Zone Studies, University of Wales, Bangor, UK. DFID/PSP (2006). 'On-Farm' Seed Priming. A key technology to improve the livelihoods of resource-poor farmers in marginal environments. Second edition. DFID/PSP information booklet, English language version. Centre for Arid Zone Studies, University of Wales, Bangor, UK, pp 20. Finch-Savage, W.E., Dent, K.C., Clark, L.J. (2004). Soak conditions and temperature following sowing influence the response of maize (Zea mays L.) seeds to on-farm priming (pre-sowing seed soak). Field Crops Res. 90, 361-374. Harris, D. (2006). Development and testing of 'on-farm' seed priming. Advances in Agronomy 90: 129-178. Harris, D., Joshi, A., Khan, P.A., Gothkar, P. and Sodhi, P.S. (1999). On-farm seed priming in semi-arid agriculture: development and evaluation in maize, rice and chickpea in India using participatory methods. Experimental Agriculture 35: 15-29. Harris, D., Pathan, A. K., Gothkar, P., Joshi, A., Chivasa, W. and Nyamudeza, P. (2001). On-farm seed priming: using participatory methods to revive and refine a key technology. Agricultural Systems 69 (1-2): 151-164. Harris, D., Rashid, A., Hollington, P.A., Jasi, L. and Riches, C. (2002). Prospects of improving maize yields with 'on-farm' seed priming. Pp 180-185 in: N.P. Rajbhandari, J.K. Ransom, K. Adikhari and A.F.E. Palmer (eds) 'Sustainable Maize Production Systems for Nepal': Proceedings of a Maize Symposium held, December 3-5, 2001, Kathmandu, Nepal. Kathmandu: NARC and CIMMYT. Harris, D., Rashid, A., Ali, S. and Hollington, P.A. (2004). 'On-farm' seed priming with maize in Pakistan. Pages 316-324 in: Srinivasan, G., Zaidi, P.H., Prasanna, B.M., Gonzalez, F. and Lesnick, K., eds 2004. Proceedings of the 8th Asian Regional Maize Workshop: New Technologies for the New Millennium. Bangkok, Thailand, 5 - 8 August 2002. Mexico, D.F.: CIMMYT. Jasi, L., Gatsi, T., Ellis-Jones, J. and Riches, C. (2000). Participatory paired-plot comparison of primed and non-primed maize seed in Zimutu and Mushagashe. In "The Role of Small Dams in the Improvement of Rural Livelihoods in Semi-Arid Areas" (J. Ellis-Jones and V. Zvarevashe, Eds.). CARE Stakeholder Workshop, Report IDG/00/18, Silsoe Research Institute, Bedford, UK. Koirala, K.B. and Ghimire, K.H. (2005). Seed priming: an easy technique to increase yield of maize and lentil. Kaski, Nepal: Regional Agricultural Research Station Lumle, pp 26. Murungu, F.S., Nyamugafata, P., Chiduza, C., Clark, L.J. and Whalley, W.R. (2003). Effects of seed priming, aggregate size, and soil matric potential on emergence of cotton (Gossypium hirsutum L.) and maize (Zea mays L.). Soil Till. Res. 74: 161-168. Murungu, F.S., Nyamugafata, P., Chiduza, C., Clark, L.J. and Whalley, W.R. (2005). Effects of seed priming and water potential on germination of cotton (Gossypium hirsutum L.) and maize (Zea mays L.) in laboratory assays. S. Afr. J. Plant Soil 22 (1): 64-70. Rashid, A., Harris, D., Hollington, P.A. and Khattak, R.A. (2002). On-farm seed priming: a key technology for improving the livelihoods of resource-poor farmers on saline lands. In "Prospects for Saline Agriculture" (R. Ahmad and K.A. Malik, Eds.), pp. 423-431. Kluwer Academic Publishers. The Netherlands. Relevant Research Projects,
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