Potential for dual-purpose maize varieties to meet changing maize demands: Synthesis
Potential for dual-purpose maize varieties to meet changing maize demands: Synthesis
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DOI：
10.1016/j.fcr.2013.10.006
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发表时间：
2013-09-01
影响因子：
5.8
通讯作者：
Erenstein, Olaf
中科院分区：
文献类型：
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作者：
Bluemmel, Michael;Grings, Elaine;Erenstein, Olaf
玉米（Zea mays L.）目前是全球最重要的产量谷物，反映了其用途的多功能性，包括人类食品、动物饲料和饲料、工业产品和生物燃料。尽管在工业化农业中利用整株植物进行青贮饲料也很常见（例如 Klopfenstein 等人，2013 年），但大多数用途都以玉米粒作为初级产品。尽管玉米是一种多功能作物，但随着时间的推移，玉米生产和玉米育种工作通常具有单一目的。例如，玉米育种的重点是克服生物和非生物胁迫，通过传统和分子育种方法的明智结合，产生高产、耐逆和广泛适应的玉米品种（Muttoni 等，2013；Shiferaw 等，2011）。即使是玉米-畜牧混合系统中的小农也通常关注玉米产量（De Groote 等，2013），并将玉米秸秆作为额外的副产品和效益。尽管农民可能仍会尝试增加饲料摄入量，但他们仍会尽量减少玉米产量损失（Byerlee等，1989；Lukuyu等，2013）。两用玉米的开发和接受的关键是谷物和饲料之间在数量和质量方面的潜在权衡。单一用途玉米可以侧重于谷物或饲料，谷物反映了玉米生物质的部分利用，而不是饲料的潜在全部（地上）生物质利用（如青贮饲料）。两用玉米侧重于谷物和饲料（特别是秸秆），并且通常是完整的（地上）生物质。一种性状（谷物）的优化本质上比两种性状（谷物和饲料）更容易，并且可以在饲料/秸秆价值可以忽略不计的情况下进行。然而，玉米秸秆的广泛使用表明它确实具有价值，尽管通常低于玉米粒。鉴于这两种性状都有价值，而且每种性状的改进可能会带来收益递减，因此双重目的育种可能具有经济意义。此外，与许多谷物类似，玉米品种似乎具有多种（谷物和秸秆）产量和秸秆质量，最有趣的是，在秸秆质量范围内有希望在不影响粮食产量的情况下提高饲料质量。正是双重用途品种的这种潜力重新激发了研究兴趣以及本特刊背后的一些研究。事实上，尽管十年前还存在怀疑，但正如本期特刊所载论文所反映的那样，在开发用于谷物和饲料的双用途玉米选择方面已经取得了实质性进展（Erenstein 等人，2013 年）。
Maize—or corn (Zea mays L.)—now is the most important global cereal in terms of production reflecting its versatility in use, including human food, animal feed and fodder, industrial products and biofuel. Most uses revolve around maize grain as the primary product, although whole plant utilization for silage is also common in industrialized agriculture (eg Klopfenstein et al., 2013). Despite being a versatile crop, maize production and maize breeding efforts over time have typically had a single-purpose orientation. For instance, maize breeding has focused on overcoming biotic and abiotic stresses so as to generate high yielding, stress-tolerant and widely-adapted maize varieties through judicious combination of conventional and molecular breeding approaches (Muttoni et al., 2013, Shiferaw et al., 2011). Even smallholders within mixed maize–livestock systems typically focus on maize grain yield (De Groote et al., 2013), with maize stover as additional byproduct and benefit. Although farmers may still try to increase fodder off-take, they still try to minimize maize grain yield loss (Byerlee et al., 1989, Lukuyu et al., 2013).Critical to the development and acceptance of dual-purpose maize are the potential trade-offs between grain and fodder both in terms of quantity and quality. Single-purpose maize can focus on either grain or fodder, with grain reflecting partial utilization of maize biomass against potentially full (above ground) biomass utilization for fodder (as in case of silage). Dual-purpose maize focuses on both grain and fodder (particularly stover), and typically the full (above ground) biomass. Optimization for one trait (grain) is inherently easier than for two traits (grain and fodder), and may be pursued in instances where the fodder/stover value is negligible. However, the widespread use of maize stover suggests it indeed has value, although typically less than the maize grain. Given that both traits have value and improvement for each is likely subject to diminishing returns, dual-purpose breeding could potentially make economic sense. Furthermore, similar to many cereals, maize varieties appear to have a wide variety of (grain and stover) yields and stover quality, and most interestingly, there are prospects within the range of stover quality to increase fodder quality without compromising grain yield. It is this potential of dual-purpose varieties that has reignited research interest and some of the research underlying this special issue. Indeed, despite earlier skepticism only a decade ago, substantial progress has been made in developing dual-purpose maize options for both grain and fodder purposes as reflected in the papers contained in this special issue (Erenstein et al., 2013).