The importance of good quality seed in increasing whole farm productivity cannot in anyway be underestimated (Minot, 2008; Kshetri, 2010; Boland et al., 2011; Guei et al., 2011; Thompson and Scoones, 2012; Entwire et al., 2013; Poonia, 2013). The green revolution of the 1960s was a compact of technologies (variety, input, credit, market, etc) yet the role improved seed cultivars/varieties played in its success is  a notable fact within the agricultural research community and various food policy think tank organizations (Briggs, 2009; Tomita, 2009; IFPRI, 2012; Cassman and Grassini, 2013). Seed is the pivotal point around which various approaches or concepts of increasing agricultural productivity revolve. Whether conventional or organic, starting with a clean, healthy and pure seed or seedling for planting is always the emphasis of farmers, agricultural extension officers, and research workers alike (Kshetri, 2010; Boland et al., 2011). Advances in molecular biology and biotechnological applications of the 21^st century have introduced novel approaches such as recombinant DNA technology for precision gene(s) isolation, cloning, and incision at the cellular level. Nevertheless, focus still remains on seed as the fundamental laboratory through which productivity issues in agriculture can be addressed. This is because almost all the products of these technologies such as increased yield (Daoura et al., 2014), pest and disease resistance (Kamthan et al., 2012; Zeller et al., 2013), improved nutrition or bio-fortification (Stein, 2008; Dawe et al., 2002; Bhullar and Gruissem, 2013) and others all rely on seed as the focal point for ‘housing’ and ‘marketing’ these technologies.

 

Against this backdrop, the issue of seed has constantly been one keenly contested, nay controversial, with various groups having their interests to promote and safeguard. Whether it is the introduction of hybrid seed and the accompanying protest by certain interest groups or the more recent sizzling debates on genetically modified (GM) crop seeds/cultivars (Halford and Shewry, 2000; Marchant, 2001; Dibden et al., 2013; Tironi et al., 2013), seed has always caused controversies in agriculture. One aspect to the debate on seed has to do with the issue of certified seed against farmer saved seed. The argument for a long time has been whether the extra costs on certified seed was really worth it? and in particular, for the self-pollinated inbreed lines of crop cultivars where farmers can make seed selection from their farms or at worse just pick lots from the grain harvested and  use same as seed the next season.

 

Researchers and extension workers alike generally stipulate that certified seed is superior to farmer saved seed, given a fundamental understanding that certified seed meets all the requirements of good seed. However, empirical evidence generated from on-farm trials to support this claim and use it as proof to convince farmers on the need to use certified seed especially for certain important grain cereals critical to food security in Ghana is lacking (Personal communication).This has often times been demanded during important policy discussions on food security in Ghana (Personal communication). With the world population expected to reach nine billion by 2050 (Falkenmark, 2001; Buhaug and Urdal, 2013), feeding the increasingly urbanized populated world is certainly one of the greatest challenges confronting humanity in this century (Koning and Ittersum, 2009). Globally, the importance of rice to food security is unquestionable to the extent that it has almost become synonymous to food security is certain geographical locations (Dawe and Timmer, 2012; Mariano and Giesecke, 2014). With a per capita consumption ranging from 21-38 kg, a national average of 22.1 kg per annum and a significant continuous increment in annual production, (Kula and Dormon, 2009; SRID, 2012), the significance of rice with respect to food security in Ghana is undisputable. With a population growth rate of 2.5% and an annual rice demand growth rate of 8.9%, a supply of 1.6 million tons of rice will be needed annually in Ghana by 2015 (Ofori et al., 2010). However, rice productivity at the local level is too low to meet this annual national rice demand (Angelucci et al., 2013). Indeed, the Ghana Minister for Food and Agriculture (MoFA) at a recent ‘Meet-the-Press’ meeting with newsmen in Accra, stated that “the average annual rice import bill stood at US$ 306 million with domestic production accounting for only 46% of total supply and the shortfall of 56% being met by imports”. The minister underscored the importance of developing a National Seed road map as an integral component of a national strategy to accelerate the growth of the rice industry (GhanaWeb, 2014).

 

Years of research breeding programmes (both locally and at international research centres) have resulted in improved genotypes of rice (Hazell, 2010; Peng et al., 2010; Renkow and Byerlee, 2010; Ragasa et al., 2013). Most of these genotypes have been made available to farmers. A great proportion of rice farmers in Ghana use improved genotypes in their cultivation (Ragasa et al., 2013). However, the average yields recorded by rice farmers in Ghana continue to fall far below the potential yields reported by research and experimental stations. In as much these farmers continue to cultivate rice paying little attention to Integrated Rice Management (IRM) recommendations which among others, underscores integrated soil fertility management (ISFM) and the use of certified rice seed planting. Numerous interventions in the rice industry have also taken place in Ghana. These notwithstanding, only about 23% of the total area currently being cropped to rice is under certified seed (Etwire et al., 2013).

 

Several yield gap analysts (Tran, 1996; Duwari et al., 1998; Evans and Fischer, 1999; Ofori et al., 2010) have suggested that this must be one of the factors why rice grain yields are always far below the average achievable yields at farm level. We report here, the results of two year on-farm trials comparing the performances of certified seed against famer saved seed of rice at different fertilizer management regimes in the Guinea-Savanna rice growing ecologies of Ghana.

Site selection and description

 

The experiments were conducted in the Guinea Savanna agro-ecological zone (GSZ) of Ghana.  Six communities were used as sites for the experiments during the two year period (Table 1; Figure 1). The selected sites were representative of the various major rice growing ecologies in the Guinea Savanna zone of Ghana. The soils in Guinea Savanna agro-ecological zone of Ghana are dominated by Savanna Ochrosols. These soils are moderately deep to deep and are generally developed over granites and stones. Decomposing rock or hard rock may be encountered within 150 cm depth. The topsoils are generally thin (<20 cm), greyish brown sandy loam, weak granular and friable. They are light, varying in texture from coarse sands to loams. The subsoils range from red in summits to brownish yellow middle slope soils (especially on some sandstone soils). Ironstone concretions and sandstone brashes of about 10 to 40% commonly occur in some of these soils. The subsoils are relatively heavy, varying from coarse sandy loams to clays with varying amounts of gravel (Adu, 1995; Asiamah et al., 1996). According to Owusu-Bennoah et al. (1995), the texture of the soils in the northern part of Ghana varies from loamy sand, sandy loam to loam. The reported pH range of the soils is from 5.4 to 6.1. Majority of the soils in the GSZ occupy gentle undulating to gently rolling topography, yet are more vulnerable to erosion than those soils occurring on the more strongly rolling relief of forest agro-ecological zones in the southern parts of Ghana. The GSZ is characterized by a uni-modal rainfall pattern with an annual mean of 1030 mm (May-October) with high degree of variability. The area has an extreme moisture regime relationship with about 5 months of rainy season and 7 months of dry season (NAES, 1993).

 

 

 

 

Table 5 depicts ANOVA results from the regression analysis for mean grain yield for certified and farmer saved seed during the two growing seasons. The analysis shows statistical significant differences (P <0.01) of treatment effect in terms of grain yield (kg/ha) for both certified and farmer saved seed sources (Table 5).

 

 

Figure 2 shows results of scatter plot and regression while Table 6 summaries descriptive statistics for mean grain yield (kg/ha) for the two cropping seasons for certified and farmer-saved seed. At the various levels of fertilizer management regimes, the performance of the seed from the certified source proved superior relative to the farmer-save seed (Figure 2; Table 6). The highest grain yield of 6833 kg/ha was recorded for T₄ - certified 

 

 

seed at full fertilizer recommendation rate for the 2012 growing season whiles the lowest grain yield of 30 kg/ha was recorded for T₀  –famer-saved seed at zero fertilizer management level in the 2012 cropping seasons (Table 6). However, comparing the mean grain yield for the two seed sources (certified and farmer saved seed) at all levels of fertilizer management, the 2011 cropping season gave comparatively higher grain yields (Table 6).

 

Whenever additional compost was introduced in the fertilizer management regime in the study, the effect proved significant, leading to a corresponding linear increment in grain yield for the various seed sources in both seasons (Table 6; Figure 2). The co-efficients of determination (r²) from the regression analysis for certified seed and farmer-saved seed are 0.97 and 0.95 respectively (Figure 2). This indicates a very close fit regression plot with above 90% of variation explained by the regression line in both the certified and farmer saved seed analysis.

 

 

Certified seed and farmer saved-seed

 

Figure 3 shows a comparison of the average grain yield for the two year cropping seasons for certified seed and farmer-saved seed. It is evident from the figure that for 2011 and 2012, at all fertilizer management levels, rice yields from certified seed plots were much higher relative to yields from farmer-saved seed fields (Table 6; Figure 3). Duwari et al. (1998); IFPRI (2012); Ragasa et al. (2013) and other workers have demonstrated the superior grain yield  advantage of certified seed in contrast to farmers-saved under various conditions. The reasons for the enhanced performance of certified seed are that: 1) it comes with high guarantee of seed viability and purity, healthiness, ensuring optimum plant population and vigorous plant establishment; 2) certified seed by virtue of being (genotypically) true-to-type of improved varieties or cultivars, is better in terms of resources use efficiency (water, radiation, soil nutrients etc.) hence will respond better to application of soil amendments including chemical fertilizers and compost (IRRI, 1998; Boland et al., 2011; Guei et al., 2011; Thompson and Scoones, 2012).

 

 

The same cannot be said of farmer-saved seed which more often lacks genetic purity. This was evident in this study as at all the levels of soil amendment regimes, the performance of the certified seed proved superior. Also, farmers and AEAs alike observed during field days that the crops from farmer-saved seed did not look as vigorous and healthy as those from the certified seed and this could have contributed to depressed yields of the FSS compared to the CS plots. The report that farmer-saved seed significantly losses it vigour after a number of years is well established in De Datta (1981); Guei et al. (2011) and Etwire et al. (2013).

 

Rice farmers in Ghana are unwilling to purchase fresh seed every year and continue to recycle seeds. The phenomenon is very common across Sub-Saharan Africa particular for rice (Dogbe et al., 2012; Etwire et al., 2013). Given the fact that certified seed is so crucial for the success of the rice industry in any rice growing ecology, innovative ideas are required to ensure that good quality seed gets to the rice farmer. One such approach is the concept of Community-based Seed System (CBSS) where farmers are taught and encouraged to use part of their rice farms as ‘seed plots’ and to apply some basic seed production principles such as, improved land preparation practices to minimize mixtures, eliminating off-types by rogueing and storage in clean bags to ensure  seed purity.

 

With the active involvement of seed inspectors from the SIU/PPRSD/MoFA good quality rice seed can be made available to many farmers at the community level. This is because the seed systems in most sub-Saharan countries are not very strong and vibrant (Etwire et al., 2013). In the interim, while every effort must be made to rapidly overcome challenges in the seed systems, the relatively quite new concept of CBSS in Ghana needs to be nurtured and developed.

 

Use of deco compost

 

The importance of organic matter to crop productivity via improvement in soil structure, improved water holding capacity, increase in the bio-availability of soil nutrients etc cannot be overstated. Indeed, Young (1976) observed that “The agricultural significance of organic matter in tropical soils is greater than that of any other property with the exception of moisture”. On the other hand, the poor health condition of soils in the Guinea Savanna zones of Ghana and West Africa, particularly with respect to organic matter content has been well documented (Vine, 1966; Asiamah et al., 1996). Summarized soil analysis data across 16 districts in Northern region (CSIR- SARI, 2009) are presented in Table 7. The leader of the soil survey team Dr. W. Dogbe made the following insights:

 

 “because of the low organic matter, low CEC and low clay levels in the soil, the nutrient holding capacity of the soil is significantly reduced. It is imperative for farmers to appreciate that the continuous use of only inorganic fertilizers on their soils cannot sustain production of cereals. There is the need therefore to enhance soil health within the cropping system through organic matter build-up”.  

 

 

 

Against this backdrop, the significantly enhanced grain yields obtained at all treatment levels which included compost relative to the preceding treatment without compost is quite well expected.

 

Results of the partial budget for 2011 and 2012 as well as the average for both years are presented in Table 8a, b, c. In the ensuing analysis a dominated treatment was eliminated.  A treatment is said to be dominated if its net benefit is lower than another. Analysis of the results showed that 0.5RR + 3 t/ha Deco compost was a dominated treatment hence it was not considered for further analysis. Returns from cultivating certified rice seed was found to be economically superior to farmer-saved seed at all levels of fertilizer management. For instance, whereas farmers who utilize certified rice seed and apply half the recommended rate of fertilizer will recoup their investment and still gain an additional income of GH¢ 2.65 for every GH¢1.00 invested, their colleagues who utilize farmer-seed will get an additional income of only GH¢1.98 (Table 8c).

 

 

 

 

Farmers who utilize certified seeds make an incremental income of GH¢0.67 for every GH¢1.00 invested over and above the additional incomes of their counterparts who utilize farmer-saved seed.

 

A change in management from no fertilizer to half the recommended rate of fertilizer as well as a change from half the recommended fertilizer rate to the full recommended fertilizer rate were both found to be profitable for certified seed and farmer saved seed as shown in Table 8c. The marginal rate of return was however found to be higher when a farmer cultivates certified seed, in fact, in the case of changing from half the recommended rate to the full recommended rate, the returns to certified seed is twice the returns to farmer-saved seed. Adding 3 tons of Deco compost per hectare to the full recommended rate of fertilizer was found not be worthwhile for both certified and farmer seed.

 

Decision criterion for fertilizer management regimes is summarised in Table 9. Clearly, applying half fertilizer rates or full rates in rice cultivation are both viable options compared to No fertilizer or Recommended rates plus 3 t/ha Deco compost. Compost application to the soil like mulching, does not perform instant miracles. It may not in the short term translate into enhanced rice yields or profit but as far as certified seed was concerned, there was a significant increase in yield of T₄ (RR + 3 t/ha compost) relative to all the other treatments. Dogbe et al. (2012) have opined that among the various ways (Conservation agriculture, Green manuring, Composting) available for improving soil organic matter, the use of compost in the short term seems to be most appropriate.

 

Returns from cultivating certified rice seed was found to be economically superior to farmer-saved seed at all levels of fertilizer management. Although there often are some concerns about the quality of seed purchased from the agro-input dealers particularly for rice in Ghana, nonetheless the results of this study show that it pays a lot to invest in certified seed. Irrespective of the fertilizer regime adopted by rice producers, they are better off cultivating certified seed as compared to farmer-saved seed. In contrast, farmers are worse off economically if they fail to apply fertilizer or apply a combination of either half or full recommended rates of fertilizer together 3 tons of Deco compost per hectare.

The authors have not declared any conflict of interest.

The authors wish to acknowledge the CSIR-SARI and the AGRA–DANIDA sponsored Agricultural Value Chain Mentorship Project for providing the support for this work. We also commend our tireless partners - Ministry of Food and Agriculture (MoFA) Directors and Agricultural Extension Agents in all the19 Districts of northern Region of Ghana in which we have been working for the last four years.