Duration of developmental phases, and dynamics of leaf appearance and tillering, as affected by source and doses of photoperiod insensitivity alleles in wheat under field conditions
Duration of developmental phases, and dynamics of leaf appearance and tillering, as affected by source and doses of photoperiod insensitivity alleles in wheat under field conditions
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DOI：
10.1016/j.fcr.2017.08.015
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发表时间：
2017-12-01
影响因子：
5.8
通讯作者：
Slafer, Gustavo A.
中科院分区：
文献类型：
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作者：
Ochagavia, Helga;Prieto, Paula;Slafer, Gustavo A.
小麦的光周期敏感性变异在作物适应广泛的农艺环境中起着重要作用。光周期不敏感由Ppd-Aa、Ppd-B1a和Ppd-D1a等位基因提供。基因组、特定Ppd-1a等位基因的剂量和来源对开花时间的影响尚未在同一实验中同时分析，更不用说在田间条件下了；在这一等位基因组合范围内，没有考虑到对特定阶段的影响，而不是只考虑总开花时间和叶长。在连续两个生长季节进行了田间试验，以评估不同Ppd等位基因和同等位基因的小麦等基因系在开花时间、组成阶段、终叶数、叶期和分蘖方面的差异。除了证实Ppd-1a等位基因的渗入提前了开花时间（如果有3个、2个或1个不敏感等位基因渗入，平均提前了307、251和191摄氏度）之外，我们还发现，光周期不敏感基因型之间的差异在很大程度上取决于Ppd-B1a的品种来源，根据供体的不同，Ppd-B1a可能比Ppd-D1a强或弱。Ppd-1a等位基因对开花时间的各个组成部分都很敏感，其中特定亚期（P < 0.001）、末叶数（P < 0.001）和晚熟叶叶时（P < 0.05）对Ppd-1a等位基因敏感，但特定组成部分上特定等位基因的强度不同，因此在不同发育阶段之间分配不同的发育时间可以实现类似的开花时间调整。我们还发现，虽然它们不影响前7个叶片的叶长，但在携带Ppd-1a的品系中，后出现的叶片的叶长持续减少。分蘖也是敏感的，但由于分蘖和分蘖死亡率之间的补偿，最终穗数不敏感。
Variation in photoperiod sensitivity in wheat plays a major role in the crop adaptation to wide agronomic environments. Photoperiod insensitivity is provided by Ppd-Aa, Ppd-B1a and Ppd-D1a alleles. Effects of the genome, doses and source of the particular Ppd-1a alleles on time to anthesis has not been analysed simultaneously in the same experiments, even less under field conditions; and the effects on particular phases rather than on considering only the total time to anthesis and on phyllochron have not been considered for this range of allele combinations. We carried out field experiments during two consecutive growing seasons to assess differences in time to anthesis, in its component phases, in final leaf number, phyllochron and tillering across wheat isogenic lines differing in specific Ppd alleles and homoeoalleles. In addition to confirming that the introgression of Ppd-1a alleles advanced anthesis time (on average by 307, 251 and 191 degrees C d if there were 3, 2 or 1 insensitivity alleles introgressed, respectively), we found that the variation between photoperiod insensitive genotypes was largely dependent on the varietal source of Ppd-B1a which could be stronger or weaker than Ppd-D1a depending on the donor considered. All components of time to flowering: the particular sub-phases (P < 0.001) as well final leaf number (P < 0.001) and phyllochron of late-appearing leaves (P < 0.05) were sensitive to Ppd-1a alleles, but the strength of particular alleles on particular components was different, so that similar adjustments in time to anthesis could be achieved with different partitioning of developmental time between the considered phases. We also found that although they did not affect phyllochron of the first 7 leaves, that of the leaves appearing later was consistently reduced in lines carrying Ppd-1a. Tillering was sensitive too, but not final number of spikes due to compensations between tillering and tiller mortality.