Seed priming in wheat, barley, sorghum, pearl and finger millet in South Asia and Africa
On-farm seed priming is a simple, proven technology that has been developed, tested, and refined in laboratories, in experimental plots, and by farmers themselves in their fields. It's easy to use with a wide range of crops in many different farming conditions. Farmers in India, Nepal, Pakistan, Botswana and Zimbabwe now prime wheat, barley, sorghum, pearl and finger millet seed before sowing. This simple method is now spreading to other countries, such as to Saudi Arabia. Although priming with water alone makes a huge difference, the method is being explored further in Pakistan. Here, the effects of adding tiny amounts of phosphorus, boron and zinc to the priming water are now being explored.
Project Ref: PSP27:
Plant Sciences Research Programme (PSP).
Good stand establishment is of the utmost importance for farmers who grow annual crops from seed because patchy stands result in low yields and, often, crop failure. Even if there is time for sparse crops to be re-sown, it is expensive and can lead poor farmers into crippling debt. Good crop establishment is especially difficult in marginal, rainfed environments where many poor farmers live. The yields of many crops characteristic of marginal conditions and grown by resource-poor farmers are constrained by drought, poor quality seeds and inadequate, untimely agronomy, the effects of which often manifest themselves as sparse stands of stressed seedlings. Such stands seldom recover and can never fulfil their genetic potential.
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. Seed priming simply involves soaking seeds in water overnight, surface-drying them to facilitate easy handling, then sowing them in the normal fashion.
Plants (wheat, barley, sorghum, pearl millet, finger millet) grown from primed seeds generally emerge earlier and in greater numbers, grow more vigorously, flower and mature earlier and often produce higher yields than those grown from non-primed seeds. The technology has been developed, tested, refined and promoted using a combination of in vitro, on-station and participatory action research with farmers in India, Nepal, Pakistan, Botswana and Zimbabwe during the period 1996-2006.
Wheat, barley, sorghum, pearl- and finger millet and other crops not covered by the PSP clusters listed below.
Seed priming, including all work funded by PSP has been reviewed recently by Harris (2006)
Seed priming is a generic technology and addresses a fundamental requirement for crop production - the need to have a field full of vigorous plants. Thus it can be incorporated with almost any other technology or process that can be used to improve crop performance. Integrated rural development programmes or initiatives that use Integrative approaches to agricultural extension and development, such as IPM, ICM or ICNM are particularly likely to promote synergies between innovations.
We know that farmers find it easy to test seed priming while trying new varieties in PVS programmes. So, for wheat, priming could be linked to, e.g. PSP, Wheat varieties for Western India, R6748 while for sorghum combination with outputs such as PSP, Rabi sorghum varieties for India, R7409 would be effective. There would be synergies for finger millet with PSP, Finger millet varieties for Karnataka, India, R7324 and CPP, Finger millet blast resistant varieties, R8445, R8030, R6733.
Value could be added in low fertility soils by linking with PSP, On-farm seed priming to improve plant nutrition in low fertility soils, R7438, R8221, R8269 for which wheat has been used as a test crop for priming with Zn, B and P.
How the outputs were validated:
In Pakistan, three series of on-farm trials implemented by 31 farmers over 3 years showed mean yield benefits due to priming of 40%, 57% and 20%. Rashid et al. (2002) primed wheat seeds overnight in two RBD trials in Nowshera district in Pakistan and significantly increased grain yield by 22.5 % and 24.3 %.
For barley, 10 RBD trials between 1998 and 2003 in Peshawar, Bannu and Nowshera districts of NWFP Pakistan gave mean grain yield increases due to priming of 23% and straw yield increases of 16%. Twenty-nine farmers primed barley seeds in three seasons between 2000 and 2002 and increased mean grain yield by 18%.
Chivasa et al. (2000) in Zimbabwe reported that priming sorghum seeds for 10 hours speeded up seedling emergence by 23 % and increased final emergence percent. Fourteen-day-old seedlings from primed seeds also had significantly more leaves and root axes and were taller and heavier than non-primed seedlings. In two field sowings in Botswana in 1991-92, primed sorghum seed gave similar results (Harris, 2006).
Forty farmers primed sorghum seed in Musikavanhu communal area in Zimbabwe during the 1997-98 season (Harris et al. 2001a). Most farmers agreed that priming accelerated emergence and plants flowered and matured earlier relative to non-primed crops. Ninety-seven percent of participants intended to prime sorghum the following year. In 1998-99, 171 farmers in the same area tested priming and described a similar range of benefits. Yields, as measured by the farmers, were reported to be an average of 27 % higher in primed plots.
A field experiment on a sandy soil in Rajasthan, India showed that emergence of pearl millet was only around 50 %, even in moist soils. However, primed seeds emerged better across a range of soil moisture levels and the relative increase due to priming increased from 15 % in moist soil to 45 % in dry soil. Priming was not able to compensate completely for the effects of low soil moisture at sowing but made a significant contribution across a range of soil moisture contents and was relatively more effective in drier soils (Harris, 2006).
Priming seeds of six cultivars of finger millet with water for 8 h in eastern India resulted in taller, earlier-maturing plants that produced more yield than plants from non-primed seed in two on-station trials in 2000 and 2001 (Kumar et al., 2002). Priming significantly reduced the mean time to flowering and the mean time to maturity by about 6 days, increased mean plant height by 9 cm and resulted in 14 % extra grain.
Wheat seed priming was validated by researchers and more than 300 farmers in India, Nepal and Pakistan (semi-arid and high potential, smallholder rainfed dry and irrigated).
Sorghum seed priming was validated by researchers and more than 200 farmers in South-eastern Zimbabwe (semi-arid, smallholder rainfed dry) and in on-station trials by researchers in Zimbabwe and Botswana (non-PSP-funded).
Barley seed priming was validated by researchers and 29 farmers in farmers in Peshawar, Bannu and Nowshera districts of NWFP Pakistan (semi-arid and high potential, smallholder rainfed dry and irrigated).
Pearl millet seed priming was validated by researchers in on-station experiments in eastern and western India (semi-arid, smallholder rainfed dry).
It is difficult to determine if seed has been primed by farmers without being in attendance at the time of sowing or asking farmers what they have done in carefully structured interviews (to enable triangulation and verification). The work to date on seed priming has been widely dispersed amongst countries and crops and it has not been possible to evaluate the extent of use in most cases.
There has been no active promotion of these outputs since validation (see under "How the outputs were validated") and it is not known if seed priming of these crops is currently being widely used. However, seed priming has been tested further in, e.g., sorghum in Saudi Arabia (Al-Soqeer, 2004) where yield increases of around 20% were measured in on-station trials.
The scale of current usage in these crops is unknown (see under "Who are the Users"), although wheat has been part of an ongoing research programme since 2003 in Pakistan to develop and test the effect of priming seeds with dilute nutrient solutions such as P, B, and Zn (Harris, 2006). Priming with water alone, as one of the treatments under test in this programme, continues to be consistently effective in increasing wheat yields.
An article in a recent UWB Newsletter, appended as Annex 2, illustrates usage of seed priming in another crop as a consequence of promotion of seed priming in general (see under "Promotion of Outputs").
Seed priming in these crops was developed and tested primarily in a research context with farmers and assuming a linear research-extension continuum. There was an expectation that the strong evidence produced would promote uptake of the technology as part of the core extension 'message'. However, our experience shows that without a local champion seed priming has not been widely promoted by line agencies. It has sometimes been said that priming is 'too simple' to be taken seriously by senior extension staff who have not been involved personally in the validation exercises.
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.
Wherever there is commitment to adaptive research and participatory extension approaches within NARES this should be encouraged but 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 seed priming.
There is no current promotion specifically for priming in any of these crops. However, more generally, CAZS-NR maintains a website (www.seedpriming.org) and 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. An example of a recent enquiry is in Annex 2.
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).
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. However, 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, particularly for crops other than the major staples. An acceptance at national level that the poor in marginal areas often have to grow minor crops to survive would be a major step forward.
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) offer a good platform for such an approach. Holistic rural development programmes are particularly suited to these approaches.
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.
Broader awareness is required of the advantages of priming seeds and how it can be combined with other technologies to benefit resource-poor farmers. It is often not appreciated how seed priming can contribute to a whole range of crop improvements. Institutionalisation of participatory approaches to agricultural and rural development would facilitate this as it would foster system-based programmes that integrate diverse outputs to reduce poverty.
Resource-poor farmers need information on the benefits of priming seeds so that they become motivated to try it for themselves. A programme of evidence-based sensitization to seed priming, followed by 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. It also facilitates close collaboration between farmers and extensionists working together to improve the whole farming system rather than isolated elements of it.
There have been no impact studies on these crops to date. Since farmers commonly report increased yield without significant additional input costs, it can be assumed that seed priming will improve productivity and profitability. Apart from access to information, there are no barriers to adopting seed priming if farmers find that it is useful to them.
Higher yields of 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.
No adverse environmental impacts are envisaged.
Lack of choice in life is a defining characteristic of poverty. The direct and indirect benefits of seed priming all give farmers and their families more choices and lead to more resilient livelihood strategies.
Annex 1 References
Al-Soqeer, A.A. (2004). The potential of seed soaking in sorghum (Sorghum bicolor L. Moench) production. PhD Thesis, University of Nottingham, U.K.
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 Journal of Agricultural Sciences 3: No. 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.
Harris, D. (2006). Development and testing of 'on-farm' seed priming. Advances in Agronomy 90: 129-178.
Harris, D., Raghuwanshi, B.S., Gangwar, J.S., Singh, S.C., Joshi, K.D., Rashid, A. and Hollington, P.A. (2001). Participatory evaluation by farmers of 'on-farm' seed priming in wheat in India, Nepal and Pakistan. Experimental Agriculture 37 (3): 403-415.
Harris, D., Pathan, A. K., Gothkar, P., Joshi, A., Chivasa, W. and Nyamudeza, P. (2001a). On-farm seed priming: using participatory methods to revive and refine a key technology. Agric. Syst. 69 (1-2): 151-164.
Kumar, A., Gangwar, J.S., Prasad, S.C. and Harris, D. (2002). 'On-farm' seed priming increases yield of direct-sown finger millet (Eleusine coracana) in India. International Sorghum and Millets Newsletter 43: 90-92.
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. Pp 423-431 in: R. Ahmad and K.A. Malik (eds.) 'Prospects for Saline Agriculture'. Kluwer Academic Publishers. The Netherlands.
Rashid, A., Hollington, P.A., Harris, D. and Khan, P. (2006). On-farm seed priming for barley on normal, saline and saline-sodic soils in NWFP, Pakistan. European Journal of Agronomy 24 (3): 276-281.
Annex 2. Article from a recent Newsletter of University of Wales, Bangor.
The power of the web!
A heart warming (and possibly mouth-warming!) story from Dr Dave Harris at CAZS Natural Resources showing that you should never underestimate the power of the internet to spread whatever your good word is.
CAZS Natural Resources have been using a low tech method of 'seed priming' which involves soaking the seeds before planting, to improve germination and consequent harvest. This work has mainly been carried out in Asia on staples such as millet, but in theory, could work for anything.
Our story moves to the heat of Sinaloa in Mexico. An entrepreneur there invested in land, greenhouses and organic seeds to introduce organic chillies to his region. He faced problems as he was only achieving germination in around 4% of his trial crop. He was at his wit's end having asked for advice locally, when he found an article about seed priming by Dr Dave Harris on the web.
He contacted Dave for further advice and reports back that having used the method, that his crop of organic chillies has flourished from 4% germination from seeds to a fantastic 95% - ensuring a success for his investment in rural Mexico!
As Dave says "I thought that this was a fantastic example of the way the system was supposed to work: research - results - website query - advice - problem solved."
Relevant Research Projects,
with links to the