Galicia-Juárez Marisol, Zavala-García Francisco, Sinagawa-García Sugey Ramona, Gutiérrez-Diez Adriana, Williams-Alanís Héctor, Cisneros-López María Eugenia, Valle-Gough Raúl Enrique, Flores-Garivay Rodrigo, Santillano-Cázares Jesús
Instituto de Ciencias Agrícolas, Universidad Autónoma de Baja California, Mexicali 21705, Baja California, Mexico.
Facultad de Agronomía, Universidad Autónoma de Nuevo León, General Escobedo 66050, Nuevo León, Mexico.
Plants (Basel). 2021 Oct 22;10(11):2265. doi: 10.3390/plants10112265.
Sorghum ( (L.) Moench) is cultivated in regions with frequent drought periods and high temperatures, conditions that have intensified in the last decades. One of the most important photosynthetic components, sensible to hydric stress, is maximum quantum yield for photosystem II (PSII, or Fv/Fm). The objective of the present study was to identify sorghum genotypes with tolerance to hydric and heat stress. The treatments were hydric status (hydric stress or non-hydric stress (irrigation)), the plant's developmental stages (pre or post-anthesis), and six genotypes. The response variables were Fv/Fm; photosynthetic rate (P); stomatal conductance (g); transpiration rate (E); relative water content (RWC); damage to cell membrane (DCM) at temperatures of 40 and 45 °C; and agronomic variables. The experiment was conducted in pots in open sky in Marín, N.L., in the dry and hot northeast Mexico. The treatment design was a split-split plot design, with three factors. Hydric stress diminished the functioning of the photosynthetic apparatus by 63%, due to damage caused to PSII. Pre-anthesis was the most vulnerable stage to hydric stress as it decreased the weight of grains per panicle (85%), number of grains per panicle (69%), and weight of 100 grains (46%). Genotypes LER 1 and LER 2 were identified as tolerant to hydric stress, as they had lower damage to PSII; LER 1 and LEB 2 for their superior RWC; and LER 1 as a thermo tolerant genotype, due to its lower DCM at 45 °C. It was concluded that LER 1 could have the potential for both hydric and heat stress tolerance in the arid northeast Mexico.
高粱（(L.) Moench）种植于干旱期频繁且温度较高的地区，在过去几十年中这些条件愈发严峻。对水分胁迫敏感的最重要光合组分之一是光系统II的最大量子产量（PSII，即Fv/Fm）。本研究的目的是鉴定对水分和热胁迫具有耐受性的高粱基因型。处理因素包括水分状况（水分胁迫或非水分胁迫（灌溉））、植株发育阶段（开花前或开花后）以及六个基因型。响应变量为Fv/Fm、光合速率（P）、气孔导度（g）、蒸腾速率（E）、相对含水量（RWC）、在40和45°C温度下的细胞膜损伤（DCM）以及农艺变量。实验在墨西哥东北部干旱炎热的新莱昂州马林市露天的花盆中进行。处理设计为裂区裂区设计，有三个因素。水分胁迫使光合机构的功能因对PSII造成的损伤而降低了63%。开花前是对水分胁迫最脆弱的阶段，因为它降低了每穗粒重（85%）、每穗粒数（69%）和百粒重（46%）。基因型LER 1和LER 2被鉴定为对水分胁迫具有耐受性，因为它们对PSII的损伤较低；LER 1和LEB 2因其较高的RWC；LER 1作为耐热基因型，因其在45°C时较低的DCM。得出的结论是，LER 1在墨西哥东北部干旱地区可能具有对水分和热胁迫的耐受性潜力。
