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Despite positive trajectories in global production during the last century, projected food demand and limits on our ability to further expand cropland now dictate an increase in food production by roughly 70% during the first half of the twenty-first century. Conventional systems of agriculture with their general emphasis on intensive soil disturbance, limited biodiversity, monoculture cropping and practices that mine the resource base are extractive and have resulted in slow yet demonstrably severe environmental degradation that ultimately jeopardizes food security for future generations. Because future gains in production are unlikely to be achieved by further increases in genetic yield potential, as have been achieved in the past, applications of new production system paradigms are going to be indispensable. Our existing ones are no longer able to compensate for, nor reverse, the environmental problems they have caused. We summarize the history of how agricultural systems have come to be what they are today and identify ways in which these systems will need to be improved to meet future food security challenges. We describe the development of food production system options that have been proposed in recent decades and show that the core principles and concepts of what are widely regarded as conservation agriculture (CA) systems provide an important unifying framework. Our chapter provides evidence for why these systems, when flexibly applied and in ways that mimic natural ecosystems, provide a best-bet approach for moving forward. We highlight a series of examples of CA systems being applied around the world and conclude by issuing a call to action aimed at developing and more widely adopting food production systems that look long-term, mimic natural systems and transcend jargon.

Many developing countries lack the facilities to produce and distribute high quality rhizobia inoculants for farmers who are interested in planting soybeans [Glycine max (L.) Merr.]. If soybean varieties were available that could nodulate effectively with the ubiquitous, cowpea‐type rhizobia, farmers could successfully grow soybeans without inoculation or fertilizer N. When 400 diverse soybean lines were tested at five sites in Nigeria for the ability to nodulate with indigenous rhizobia, only 10 were highly promiscuous, that is, capable of forming an effective symbiosis at all sites. Some entries were rated as compatible with indigenous rhizobia at one or two sites but failed to nodulate profusely at the other locations. Twenty‐two isolates from nodules collected from profusely nodulated soybean plants and three other isolates prepared from cowpea nodules, were used to inoculate the 10 most compatible selections from the previous trial and two U.S. varieties, ‘Bossier’ and TGm 294. ‘Malayan’, a local Nigerian cultivar, formed an effective symbiosis with 21 of 22 soybean isolates; nodule and shoot weights in each case being greater than or equal to inoculation with Nitragin multistrain inoculant. Other accessions that displayed high degrees of promiscuity were M‐381, TGm 120, TGm 119, Indo 180, and Indo 243. Whereas, Bossier formed an effective symbiosis with only one of the isolates, and TGm 294 was compatible with only 2 of the 22 rhizobia isolates. The promiscuously nodulating soybeans identified in the screening trial were also compatible with at least two of the three cowpea isolates, but Bossier and TGm 294 were compatible with none of them. When the scion of Bossier on ‘Jupiter’ (both of which have high yield potential) was grafted onto the root stocks of ‘Orba’ or Malayan (Promiscuous nodulators) enough N was fixed to meet the requirements of high yielding genotypes. These results indicate that by genetically incorporating promiscuity into varieties with high yield potential one would not necessarily reduce yield potential.

Soybean [Glycine max (L.) Merr.] seeds may lose vigor prior to harvest, especially when grown in humid, tropical environments. This study compared three seed weathering treatments to identify soybean genotypes with resistance to field weathering of seed. Thirty‐five genotypes were planted in replicated trials on three dates and subjected to 1) field weathering (seeds were harvested 3 weeks after physiological maturity), 2) incubator weathering (pods at physiological maturity were detached from the plant and kept at 30°C and 90 to 95% relative humidity for 10 days), and 3) wet‐bag weathering (plants at physiological maturity were placed in wet burlap bags for 10 days). Under the wet‐bag treatment, extreme seed deterioration of nearly all genotypes tended to mask their differences in resistance. Incubator weathering was more consistent across experiments than field weathering. Mean seedling emergence scores varied less among experiments for incubator weathering (30, 28, and 22%) than for field weathering (78, 46, and 54%). The genotype ✕ planting date interaction accounted for 7 and 29% of the total sums of squares for incubator and field‐weathering, respectively, indicating that incubator weathering minimized environmental effects that would confound comparisons among genotypes of different maturity. The percentage of hard seed after 1 h of soaking ranged from 0 to 64% and was correlated (r = 0.73, P < 0.01) with seedling emergence following incubator weathering. Large‐seeded genotypes were generally susceptible to seed weathering and deterioration in storage. Some small‐seeded genotypes were resistant; others were susceptible. Black‐seeded genotypes were more resistant to incubator weathering than yellow‐seeded genotypes. Genotypes with a high percentage of seedling emergence following incubator weathering also had high seedling emergence after ambient storage. Genotypes identified as having resistance to weathering of seed and to deterioration in storage were: INDO 153, INDO 131, INDO 243, INDO 226, INDO 255, ‘Fort Lamy’, ‘Lee A’, INDO 173A, and ‘Biloxi 3’.

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