Bochicchio Rocco, Labella Rosanna, Rossi Roberta, Perniola Michele, Amato Mariana
School of Agriculture, Forestry, Food and Environmental Sciences, University of Basilicata, 85100 Potenza, Italy.
Council for Agricultural Research and Economics, Research Centre for Animal Production and Aquaculture (CREA-ZA), 85051 Bella (Potenza), Italy.
Plants (Basel). 2022 Dec 13;11(24):3492. doi: 10.3390/plants11243492.
Ancient wheats may be a source of traits that are useful for the tolerance of climate change foreseen conditions of raising temperatures and low water availability. Previous research has shown a fine root system and a high mass of rhizosheath per unit root mass in the italian durum wheat ( Desf) landrace Saragolle Lucana, and this may be relevant for successfully facing adverse conditions during seedling establishment. We investigated the effect of soil water shortage in Saragolle seedlings on root architecture, rhizosheath formation and biomass allocation. Pot experiments were conducted by comparing two levels of soil available water content (AWC): WW (100% of AWC) and DS (50% of AWC). Phenology was delayed by eight days in DS and above and belowground traits were measured at Zadoks 1.3 for each treatment. Biometric data collected at the same phenological stage show that DS plants did not reach the levels of biomass, surface area and space occupation of WW even after attaining the same developmental stage. Namely, plant dimensions were lower at low soil water availability, with the exception of rhizosheath production: DS yielded a 50% increase in rhizosheath mass and 32% increase in rhizosheath mass per unit root mass. The proportion of plant mass reduction in DS was 29.7% for aboveground parts and 34.7% for roots, while reductions in leaf and root surface areas exceeded 43%. The root/shoot mass and area ratios were not significantly different between treatments, and a higher impact on aboveground than on belowground traits at reduced available water was shown only by a lower ratio of shoot height to root depth in DS than in WW. Increases in rhizosheath in absolute and relative terms, which were observed in our experiment in spite of smaller root systems in the ancient durum wheat variety Saragolle lucana at DS, may provide an interesting trait for plant performance in conditions of low soil water availability both for water-related issue and for other effects on plant nutrition and relations with the rhizosphere.
古老的小麦可能是一些性状的来源，这些性状有助于耐受气候变化所预见的气温升高和水资源短缺状况。先前的研究表明，意大利硬粒小麦（Desf）地方品种萨拉戈勒卢卡纳具有良好的根系，且单位根质量的根际鞘质量较高，这可能与在幼苗期成功应对不利条件有关。我们研究了土壤水分短缺对萨拉戈勒幼苗根系结构、根际鞘形成和生物量分配的影响。通过比较两种土壤有效含水量（AWC）水平进行盆栽试验：WW（AWC的100%）和DS（AWC的50%）。在DS处理中物候期延迟了8天，并且在每个处理的生长阶段1.3（Zadoks分期）测量地上和地下性状。在相同物候期收集的生物特征数据表明，即使达到相同的发育阶段，DS处理的植株在生物量、表面积和空间占据方面仍未达到WW处理的水平。也就是说，在低土壤水分条件下植株尺寸较小，但根际鞘产量除外：DS处理的根际鞘质量增加了50%，单位根质量的根际鞘质量增加了32%。DS处理中地上部分生物量减少比例为29.7%，根系为34.7%，而叶片和根系表面积减少超过43%。各处理间根冠质量比和面积比无显著差异，仅DS处理的株高与根深度比低于WW处理，表明在有效水分降低时对地上性状的影响大于对地下性状的影响。尽管在DS处理下古老硬粒小麦品种萨拉戈勒卢卡纳的根系较小，但我们的实验中观察到根际鞘在绝对和相对方面均有所增加，这可能为低土壤水分条件下植株的表现提供一个有趣的性状，无论是与水分相关的问题，还是对植物营养及与根际关系的其他影响。
