Perennial grains hold promise, especially for marginal landscapes or with limited resources where annual versions struggle.

Consumer demand regarding the impacts of conventional agriculture on the environment and human health have spurred the growth of organic farming systems; however, organic agriculture is often criticized as low-yielding and unable to produce enough food to supply the world's population. Using wheat as a model crop species, we show that poorly adapted cultivars are partially responsible for the lower yields often found in organic farming systems when compared with conventional farming systems. Our results demonstrate that the highest yielding soft white winter wheat genotypes in conventional systems are not the highest yielding genotypes in organic systems. An analysis of variance for yield among 35 genotypes between paired organic and conventional systems showed highly significant (P < 0.001) genotype  system interactions in four of five locations. Genotypic ranking analysis using Spearman's rank correlation coefficient (R S ) showed no correlation between genotypic rankings for yield in four of five locations; however, the ranks were correlated for test weight at all five locations. This indicates that increasing yield in organic systems through breeding will require direct selection within organic systems rather than indirect selection in conventional systems. Direct selection in organic systems produced yields 15%, 7%, 31% and 5% higher than the yields resulting from indirect selection for locations 1-4, respectively. With crop cultivars bred in and adapted to the unique conditions inherent in organic systems, organic agriculture will be better able to realize its full potential as a high-yielding alternative to conventional agriculture. Published by Elsevier B.V.

a b s t r a c tIt is estimated that more than 95% of organic production is based on crop varieties that were bred for the conventional high-input sector. Recent studies have shown that such varieties lack important traits required under organic and low-input production conditions. This is primarily due to selection in conventional breeding programmes being carried out in the background of high inorganic fertilizer and crop protection inputs. Also, some of the traits (e.g., semi-dwarf genes) that were introduced to address problems like lodging in cereals in high-input systems were shown to have negative side-effects (reduced resistance to diseases such as Septoria, lower protein content and poorer nutrient-use efficiency) on the performance of varieties under organic and low-input agronomic conditions. This review paper, using wheat, tomato and broccoli as examples, describes (1) the main traits required under low-input conditions, (2) current breeding programmes for organic, low-input agriculture, (3) currently available breeding and/or selection approaches, and (4) the benefits and potential negative side-effects of different breeding methodologies and their relative acceptability under organic farming principles.

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The diet of approximately three billion people worldwide is nutrient deWcient and most of the world's poorest people are dependent on staple food crops as their primary source of micronutrients. One component of the solution to nutrient deWciencies is collaboration among plant breeders, cereal chemists and nutritionists to produce staple crop cultivars with increased mineral nutrient concentration. Sixty-three historical and modern wheat cultivars were evaluated for grain yield and concentration of calcium, copper, iron, magnesium, manganese, phosphorus, selenium, and zinc. While grain yield has increased over time, the concentrations of all minerals except calcium have decreased. Thus a greater consumption of whole wheat bread from modern cultivars is required to achieve the same percentage of recommended dietary allowance levels contributed by most of the older cultivars. The decrease in mineral concentration over the past 120 years occurs primarily in the soft white wheat market class, whereas in the hard red market class it has remained largely constant over time. This suggests that plant breeders, through intentional selection of low ash content in soft white wheat cultivars, have contributed to the decreased mineral nutrient concentration in modern wheat cultivars. These results contradict the theory that there exists a genetically based, biological trade-oV between yield and mineral concentrations. Therefore, using the abundant variation present in wheat cultivars, it should be possible to improve mineral concentrations in modern cultivars without negatively aVecting yield.

Growers in low‐precipitation (<300 mm annual) dryland wheat‐fallow areas of the inland Pacific Northwest need winter wheat (Triticum aestivum L.) cultivars that emerge from deep sowing depths in dry soils. Stand establishment is the most important factor affecting winter wheat grain yield in this region. Despite poor resistance to disease, modest grain yield potential, and other problems, the outdated soft white winter wheat (SWWW) cultivar Moro is widely sown in these dry areas, due to its excellent emergence ability. All other SWWW cultivars are semidwarfs that carry emergence‐impeding Rht1 or Rht2 reduced‐height genes. From 12 sowing trials at 2 locations over 4 yr, we compared the emergence capability of Moro to (i) 8 SWWW cultivars and (ii) 16 SWWW advanced experimental Mororeplacement lines. Under both wet and dry soil conditions (soil water content in the seed zone ranged from 11 to 19 mm3 mm−3), seeds were sown deep, with 110 to 160 mm of soil cover. Moro always emerged fastest and achieved the best final stand compared with the semidwarf cultivars. The advanced experimental lines, which contained either no reduced‐height gene or a Rht1, Rht2, or Rht8 reduced‐height gene, had superior straw strength, disease resistance, and grain quality compared with Moro. The best‐emerging advanced experimental lines had coleoptile lengths >100 mm. Coleoptile length was associated with emergence capability among both cultivars (r2 = 0.71, P < 0.004) and advanced lines (r2 = 0.62, P < 0.001). From deep sowing depths in this study: (i) cultivars and advanced lines with Rht1 and Rht2 reduced‐height genes always emerged poorly compared with Moro; (ii) the Rht8 reduced‐height gene did not hamper emergence to the extent that Rht1 and Rht2 did; and (iii) several advanced experimental lines with long coleoptiles equaled or exceeded Moro for emergence.

Organic and low-input farmers often plant seed varieties that have been selected under conventional practices, traditionally including high inputs of artificial fertilizers, crop protection chemicals and/or water. In addition, these crops are often selected in environments that may or may not represent the local environment of the farmer. An evolutionary participatory breeding (EPB) method emphasizes the utilization of natural selection in combination with site-specific farmer selection in early segregating generations of a heterogeneous crop population. EPB is a combination of two specific breeding methods, evolutionary breeding and participatory plant breeding. Evolutionary breeding has been shown to increase yield, disease resistance, genetic diversity and adaptability of a crop population over time. It is based on a mass selection technique used by farmers for over 10,000 years of crop improvement. Participatory plant breeding programs originated in developing countries to meet the needs of low-input, small-scale farmers in marginal environments who were often overlooked by conventional crop breeders. The EPB method is an efficient breeding system uniquely suited to improving crop varieties for the low-input and organic farmer. The EPB method utilizes the skills and knowledge of both breeders and farmers to develop heterogeneous landrace populations, and is an effective breeding method for both traditional and modern farmers throughout the world.

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