Grain Zn concentrations and yield of Zn-biofortified versus Zn-efficient rice genotypes under contrasting growth conditions
Grain Zn concentrations and yield of Zn-biofortified versus Zn-efficient rice genotypes under contrasting growth conditions
复制标题
DOI：
10.1016/j.fcr.2019.01.011
复制
发表时间：
2019-03-15
影响因子：
5.8
通讯作者：
Wissuwa, M.
中科院分区：
文献类型：
--
作者：
Goloran, J. B.;Johnson-Beebout, S. E.;Wissuwa, M.
在“生物强化”水稻基因型中，为提高籽粒锌浓度而培育的基因型不应以降低籽粒产量为代价。本研究在菲律宾的田间试验中检测了生物强化锌基因型的籽粒产量和籽粒锌浓度。在5个不同锌缺乏类型和程度的试验点（Bay、Bohol、Bukidnon和IRRI），对锌生物强化基因型（富锌土壤中高锌粒浓度）与高效基因型（耐土壤缺锌）、低效基因型（对土壤缺锌敏感）和对照基因型（流行的地方品种）进行了比较。试验时间为5个种植季（2012年、2014年和2015年雨季和2013年和2015年旱季）。采用普通试验设计和小区大小，处理（基因型和锌施肥）采用二因子随机完全区组设计。结果表明，只有在锌充足的条件下生长，生物强化基因型才能达到菲律宾粮食产量目标（4.0 t / h(-1)）和谷物锌生物强化目标（糙米30 mg / kg(-1)）。在缺锌土壤中，大多数生物强化锌和耐缺锌基因型达到了锌浓度目标，但未达到产量目标，表明需要纠正土壤缺锌以防止产量损失。此外，IRRI的结果表明，只有施锌的植株才能在雨季达到锌的生物强化目标；而在旱季，土壤化学还原程度较低，因此土壤锌可能更有利于植物利用，无论施用或不施用锌，籽粒锌水平均高于阈值。这表明，在具有足够潜在植物可利用锌的土壤中，旱季可能不需要施锌。
Higher grain Zn concentration in 'biofortified' rice genotypes, bred for high grain Zn concentration, should not be at the expense of reduced grain yield. This study examined the grain yield and grain Zn concentration of Zn-biofortified genotypes in field experiments in the Philippines. Zinc-biofortified genotypes (high grain Zn concentration in Zn-sufficient soil) were compared with efficient genotypes (tolerant of soil Zn deficiency), inefficient genotypes (sensitive to soil Zn deficiency) and check genotypes (popular local varieties) at four sites (Bay, Bohol, Bukidnon and IRRI) with differing types and degrees of Zn deficiency, over five cropping seasons (wet season 2012, 2014 and 2015 and dry season 2013 and 2015). A common experimental design and plot size were used with treatments (genotypes and Zn fertilization) arranged in a two-factorial randomized complete block design. The results showed that biofortified genotypes achieved both the Philippine grain yield target (4.0 t ha(-1)) and grain Zn biofortification target (30 mg kg(-1) for brown rice) only when grown under Zn-sufficient conditions. In Zn-deficient soils, most Zn-biofortified and deficiency-tolerant genotypes reached the Zn concentration target but not the yield target, suggesting the need to correct the soil Zn-deficiency to prevent yield penalty. Further, results from IRRI showed that only Zn-fertilized plants were able to achieve the Zn biofortification target during the wet season; whereas during the dry season, when the soil was less chemically reduced and therefore the soil Zn probably more plant-available, grain Zn levels were all above the threshold, with or without Zn fertilizer. This suggests that Zn fertilization may not be needed during the dry season in soils with sufficient potentially plant-available Zn.