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Selecting genotypes that combine high productivity with high seed quality is a challenge. The exploration of intracultivar genetic variation is an alternative to significantly increase the annual genetic gain and maximize the selection efficiency for both characteristics. The present study aimed to identify intracultivar variation to improve the seed quality of soybean genotypes derived from the commercial cultivar BRS 284, selected using the HSD (Honeycomb Selection Designs) model. Soybean genotypes selected for two years from two environments with contrasting edaphoclimatic characteristics, according to the principles of the HSD selection model, were cultivated under competition by using the experimental model in randomized blocks with four replicates and evaluated regarding the productivity and physiological quality of seeds. The results showed that genotype 284-3 presented a greater mass of 100 seeds, germination, vigour after accelerated ageing test, seedling emergence and emergence speed index than the other genotypes in both environments, with no significant difference in the standard cultivar regarding seed yield. The HSD method was an efficient selection method to identify intracultivar variation to improve cultivar performance. Selecting genotypes that combine high productivity with high seed quality is a challenge. The exploration of intracultivar genetic variation is an alternative to significantly increase the annual genetic gain and maximize the selection efficiency for both characteristics. The present study aimed to identify intracultivar variation to improve the seed quality of soybean genotypes derived from the commercial cultivar BRS 284, selected using the HSD (Honeycomb Selection Designs) model. Soybean genotypes selected for two years from two environments with contrasting edaphoclimatic characteristics, according to the principles of the HSD selection model, were cultivated under competition by using the experimental model in randomized blocks with four replicates and evaluated regarding the productivity and physiological quality of seeds. The results showed that genotype 284-3 presented a greater mass of 100 seeds, germination, vigour after accelerated ageing test, seedling emergence and emergence speed index than the other genotypes in both environments, with no significant difference in the standard cultivar regarding seed yield. The HSD method was an efficient selection method to identify intracultivar variation to improve cultivar performance.

O desenvolvimento deuma nova cultivar representa o objetivo final dos programas de melhoramento genético e é fruto de muitos anos de trabalho e esforço dos melhoristas e suas equipes. Uma parte importante do processo muitas vezes negligenciada pelos melhoristas é a etapa da recomendação a produção de semente genética (pós-melhoramento). Neste trabalho são discutidos o papel do melhorista na recomendação, registro, proteção e marketing das novas cultivares. O envolvimento do melhorista em todas as fases do pós-melhoramento é de fundamental importância para que a cultivar chegue rapidamente aos agricultores e possa proporcionar os ganhos esperados pela sociedade. The development of new cultivars is the ultimate goal of breeding programs and is the result of many years of hard work and dedication of breeders and their teams. An important part of the process, often neglected by geneticists, is the stage from recommendation to the production of breeder seed (post-breeding). This paper discusses the role of the breeder in the recommendation, registration, protection and marketing of new cultivars. The breeder’s active participation in all phases of post-breeding is fundamental to ensure that the cultivar reaches farmers quickly and can provide the benefits expected by society.

Yield losses occurring at the field level, whether due to plant diseases or abiotic stresses, reveal reduced stability of the crop yield potential. The paper argues that the stability of crop yield potential is a trait with a clear genetic component, which can be successfully selected for at the single-plant level and incorporated into high-yielding cultivars. Two novel selection equations with prognostic power are presented, capable to objectively phenotype and evaluate individual plants in real field conditions in the absence of the masking effects of interplant competition and soil heterogeneity. The equations predict performance at the crop stand through the key concept of coefficient of homeostasis and are equally useful for early generation selection and for nonstop selection within finished cultivars in order to continuously incorporate the adaptive (genetic or epigenetic) responses of plants. Exploitation of adaptive responses acquires particular importance in view of the climate change effects on crop productivity and the changing biotic or abiotic micro-environments. Cotton is used as a case study to highlight the potential of nonstop selection for increasing crop yield and for the gradual build-up of disease resistance. In addition, the paper envisions and proposes the formation of international networks of researchers focusing on specific diseases as, for example, the cereal root-rot or the cotton Verticillium wilt that will concurrently use the proposed strategy in their respective environments to select for resistant genotypes, while gaining a deeper understanding of the nature of the genetic or epigenetic changes at the phenotypic and genomic levels.

Prevalence of Bacterial Stripe Organism, Acidovorax avenae subsp. avenae, in Breeder Rice Seed Samples from Burkina Faso. Nine rice seed samples of improved and local varieties were tested at DGISP (Denmark) for the incidence of seed-borne bacterial stripe organism, Acidovorax avenae subsp. avenae, using the cassette holder method. Twenty-six suspected bacterial colonies were identified by different methods including colony morphology, pigmentation, biochemical and pathogenicity tests. Using Biolog GN computer identification system, isolates were also identified as A. avenae subsp. avenae (sim 0.51 to 0.9). All the 26 isolates reacted positively in ELISA tests performed with antiserum against A. avenae subsp. avenae. The bacterium was detected in all the samples, except in that of the local variety, indicating that seeds of improved varieties are highly infected by this pathogen. Seedlings raised from infected seed samples showed typical bacterial stripe symptoms with infection rates ranging from 4.7 to 20.1%. Since such seeds are used for production of certified rice seed, it is important to develop an effective control strategy against this disease to reduce the propagation of the bacterial agent in other healthy regions of rice culture in Burkina Faso.

Mozambique, the only Lusophone country covered in the agribusiness indicators initiative, has had a turbulent history since independence. Civil unrest over some 20 years and frequent drought in southern Mozambique, coupled with floods near the many waterways that transect the country (mainly east-west), have inhibited an agricultural transformation. Even so, Mozambique could be a regional breadbasket. The country has much potentially usable arable land, along with access to river water for irrigation in many agricultural production zones, particularly in central and northern Mozambique. Sesame, pigeon peas, and cashew exports are significant and rising, not to mention exports of industrial crops such as cotton, leaf tobacco, and sugarcane, yet production of grain and most other food crops remains stagnant. Irrigated area is way below what is possible and needed to increase yields and total agricultural output.

Because agriculture is the economic backbone of most countries in Sub-Saharan Africa, including Ethiopia, any meaningful sustainable development program in the continent must therefore be anchored in the sector. The concept for this study on agribusiness indicators was based on the vital role that agribusiness plays in agricultural development. The study focuses on agribusiness indicators (ABI) to identify and isolate the determining factors that lead private investors and other stakeholders to participate in agribusiness and to engage in discourse regarding its development. A more thorough empirical understanding of these determinants in turn can usefully inform the types of policy reforms that can promote agribusiness in Africa. In Ethiopia, the ABI team focused on the following success factors: a) access to critical factors of production of certified hybrid seeds, fertilizer, and mechanical input; b) enabling environment in terms of access of credit and transportation; and c) government expenditures on agriculture, and trade and regulatory policies that currently influence the agribusiness environment. The factors and indicators that the research team has included in this study are not exhaustive but rather are intended to serve as a pilot that could be scaled up to include more variables and countries. The findings of the study revealed the dominant role of the government in the seed and fertilizer markets. In the seed sub-sector, perennial shortages of both basic and certified seeds have greatly limited agricultural productivity in Ethiopia.

The use of quality seed is a major component of increased yields in crop production. Quality seed and seed programs in a country does not emerge by happenstance; it is created by a combination of many factors that include variety development, seed production, quality control, processing, marketing, and governmental oversight. As the seed sector in a country matures, each of these factors becomes more important and plays a more important role in the growth of the agricultural sector. The seed program in Cambodia is interestingly different from that in many other developing countries. Even without a true seed program in Cambodia, farmers understand the need to plant quality seed to increase crop yields. When structuring this growing seed industry, it is important to look at current practices and to incorporate these practices into programs. Since a major thrust of the seed program in Cambodia involves rice, it is important to consider its role in the average Cambodian’s life. Cambodia’s climate must also be accounted for in any decisions regarding seed. Its heat and humidity causes rapid deterioration of seed viability and germination in rice and other seeds in both the growth and storage phases. CARDI research has shown that the level of rice germination falls below 80-85 percent within 6-8 months after harvest; this means that seed must be planted during the growing season following harvest. Therefore, any seed produced beyond immediate planting needs for the next crop is used for milling; seed production costs for that seed cannot be recouped. When seed producers’ budgets are constrained, they often plan their seed production based on conservative seed sales estimates.

Many transition and developing economies have reduced direct public involvement in the production and trade of seed and other agricultural inputs. This trend creates opportunities for farmers to realize improved access to inputs, including technology from international private research. Unfortunately, input regulations often derail these opportunities by blocking private entry and the introduction of private technology. This study looks at the experience in Bangladesh, India, Turkey, and Zimbabwe to see whether regulations make a difference in agriculture and input industries in developing economies. In all countries, companies and farmers responded to regulatory reforms by introducing and adopting more new technology and by expanding the production, trade, and use of inputs. The increased use of private technology has brought higher yields and incomes, allowing farmers and consumers to reach higher levels of welfare. These results challenge governments to open their regulatory systems to allow market entry and the introduction of private technology through seeds and other inputs.