Interspecific differences in root architecture among maize and triticale genotypes grown under drought, waterlogging and soil compaction

Abstract

Environmental stresses (soil compaction, drought, waterlogging) cause changes in plants' root system structure, also affecting the growth of above-ground parts. The aim of this study was to estimate phenotypic variation among maize and triticale genotypes in root penetration ability through petrolatum-wax-layer (RPA). Also, the effect of shortage or excess of soil water on dry matter of shoots and roots and morphological changes in root system structure in sensitive and resistant maize and triticale genotypes grown in low or high soil compaction level was evaluated. To estimate RPA index, the petrolatum-wax-layer method (PWL) was used. The strength of three petrolatum-wax concentrations 60, 50 and 40 % was 0.52, 1.07 and 1.58 MPa, respectively. High coefficients of variation (CV) were observed in 0.52 and 1.07 MPa and for maize were 19.2 and 21.7 %, and for triticale, 12.5 and 18.3 %, respectively. The data indicate that the use of PWL technique is an effective screening method, and makes it possible to divide the genotypes into resistant and sensitive groups. The second part of this study investigated a multistress effect of soil compaction combined with drought or waterlogging on root and shoot growth and morphological changes in root system structure of maize and triticale genotypes differing in susceptibility to environmental stresses. Seedlings were grown for 4 weeks in root-boxes under conditions of low (LSC 1.1 g cm -3 ) or severe (SSC 1.6 g cm -3 ) soil compaction. Drought or waterlogging stresses were applied for 2 weeks from 14th to 28th day. In comparison to LSC treatment, in SSC treatment the decrease in dry matter of shoots and roots was greater for sensitive genotypes of maize and triticale (Ancora, CHD-147). Soil drought or waterlogging caused greater decrease of dry matter of shoots and roots in seedlings grown in SSC in comparison to LSC. The root penetration index (RPI) was estimated as a ratio of root dry matter in 15-40 cm root-box layer to total root dry matter. On the basis of RPI it was possible to group the genotypes according to their ability to distribute roots in soil profile. In comparison to LSC, SSC exerted a strong influence on the length of seminal and seminal adventitious roots, as well as the number and length of L-and S-type lateral roots developed on seminal and nodal roots. In both species the restriction effect of soil compaction on number and length of roots was more severe in sensitive (Ankora, CHD-147) than in resistant (Tina, CHD-247) genotypes. The restriction in roots propagation was greater in triticale than in maize. Exposure to drought or waterlogging in the case of genotypes grown in LSC and SSC treatments caused a decrease in number and length of particular components of root system structure. In both species the decrease of root number and length in plants grown under waterlogging was greater than under drought. The observed changes in root system were greater in sensitive (Ankora, CHD147) than in resistant (Tina, CHD-247) genotypes. Statistically signif...

Genetic Diversity under Soil Compaction in Wheat: Root Number as a Promising Trait for Early Plant Vigor

“…These phenotypic responses are consistent between different crop species including major mono- and dicotyledonous crops such as small grain cereals, maize or soybean (Tracy et al, 2012; Chen Y.L. et al, 2014; Grzesiak et al, 2014; Pfeifer et al, 2014; Colombi and Walter, 2016). Apart from shallower root growth and increased root diameters, crop root systems show decreased axial and lateral root numbers in response to soil compaction.…”

“…Apart from shallower root growth and increased root diameters, crop root systems show decreased axial and lateral root numbers in response to soil compaction. In most of these studies such alterations of the root phenotype resulted in decreased shoot biomass both under laboratory (Grzesiak et al, 2014; Pfeifer et al, 2014) and field conditions (Chen Y.L. et al, 2014; Colombi and Walter, 2016).…”

Impact of soil compaction stress combined with drought or waterlogging on physiological and biochemical markers in two maize hybrids

“…W) for 14 days with good performance in stress and non-stress conditions, second-with good performance only in non-stress conditions, third-with good performance only in stress conditions and fourth-with weak performance in both types of conditions (Golbashy et al 2010, Grzesiak et al 2014b). According to Grzesiak et al (2014a), seedlings of maize hybrids and triticale cultivars which were tolerant to soil compaction were found to be tolerant also to drought or waterlogging. According to Kono et al (1987), Iijima et al (1991) and Grzesiak et al (2014b) cereal species grown under drought or waterlogging conditions can be divided into the following groups: (1) species which were susceptible to drought and most stable to waterlogging (lowland and upland rice), (2) the species which were stable to drought and waterlogging (finger millet) and (3) the species which were susceptible to waterlogging but resistant to drought (maize, sorghum).…”

Contributions of rational soil tillage to compaction stress in main peanut producing areas of China

“…There have been a number of root change studies from numerous crops under soil tillage intensities19323738. However, detailed analyses of the responses of root and other underground parts (e.g., pod) to soil compaction are limited.…”