Silva C M, Miranda Filho J B, Mendes U C, Reis E F
Programa de Pós-Graduação em Agronomia, Universidade Federal de Goiás, Jataí, GO, Brasil.
Departamento de Genética, Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, Piracicaba, SP, Brasil.
Genet Mol Res. 2017 Feb 8;16(1):gmr-16-01-gmr.16019544. doi: 10.4238/gmr16019544.
In Brazil, the total production of maize has increased continuously due to the advances in technology but also to the new frontiers for the maize crop, including the expansion of the second crop (safrinha; usually maize after soybean). Therefore, the exploitation of new sources of germplasm seems to be imperative to attend the actual and future demands for modern cultivars adapted to the greatly variable environments available to the maize crop. The present study was based on a partial diallel (intergroup) cross to provide quantitative information on the potential of two groups of varieties (NAP - exotics and HG - local) and their combining abilities to direct the synthesis of new populations to be used in hybrid crosses or as a base for breeding programs. The experiments were carried out in two planting seasons (safra - 1st crop; safrinha - 2nd crop) following the completely randomized block design with four replications of plots 5 m long spaced 0.9 m with 25 plants per plot after thinning. The following traits were analyzed: male flowering (days), stalk diameter (mm), plant height (m), ear height (m), tassel length (cm), tassel branch number, ear length (cm), ear diameter (cm), ear yield (t/ha), and grain yield (t/ha). The populations under study presented acceptable levels for yield potential and agronomic traits, thus assuring good perspectives for their use in breeding programs. The prediction for the new populations to be synthesized from the cross between the two groups of varieties contributed positively and HG-3 population was the most appropriate, in both eras, as the parent variety most promising in Group II (HG to be used as a base) for incorporation of varieties of Group I (NAP).
在巴西，由于技术进步以及玉米作物新种植区域的出现，包括第二季作物（夏播玉米；通常是大豆之后种植玉米）种植面积的扩大，玉米总产量持续增长。因此，开发新的种质资源对于满足当前和未来对适应玉米作物广泛多样环境的现代品种的需求似乎至关重要。本研究基于部分双列杂交（组间杂交），以提供关于两组品种（NAP - 外来品种和HG - 本地品种）的潜力及其配合力的定量信息，从而指导合成用于杂交或作为育种计划基础的新群体。试验在两个种植季节（第一季作物；夏播第二季作物）进行，采用完全随机区组设计，小区长5米，间距0.9米，间苗后每小区保留25株，重复四次。分析了以下性状：雄穗开花期（天）、茎粗（毫米）、株高（米）、穗位高（米）、雄穗长度（厘米）、雄穗分枝数、穗长（厘米）、穗粗（厘米）、穗产量（吨/公顷）和籽粒产量（吨/公顷）。所研究的群体在产量潜力和农艺性状方面表现出可接受的水平，因此确保了它们在育种计划中的良好应用前景。对两组品种杂交合成的新群体的预测产生了积极贡献，在两个时期，HG - 3群体都是最合适的，作为第二组（HG用作基础）中最有前景的亲本品种，用于整合第一组（NAP）的品种。
