Maize root morphology responses to soil penetration resistance related to tillage and drought in a clayey soil

Abstract

SUMMARYCrops often experience combined soil stresses. Root responses to soil penetration resistance (PR) and drought stress can be an important basis for crop management. In 2013/14, a 2-year experiment was conducted to evaluate the effect of tillage treatment and drought stress (no irrigation for 4, 12 and 20 days during the V10–V16 growth stage) on the root length, diameter, cortex and cortical cell, and grain yield of maize (Zea mays L.) in a clayey red soil in southern China. Total root length and average root diameter were significantly correlated with soil PR and moisture. The cortical cell file number increased with soil PR and drought stress, while cortical cell size increased only with soil PR. Soil PR and moisture played different roles in maize root morphology modifications, but were both affected by tillage practices. Deep ploughing and conventional tillage increased soil moisture under severe drought stress conditions, whereas soil compaction and no-till significantly increased soil PR. The results indicate that high PR in clayey red soil was responsible for a decrease in maize root size and grain yield under drought conditions.

Root Response of Moso Bamboo (Phyllostachys edulis (Carrière) J. Houz.) Seedlings to Drought with Different Intensities and Durations

“…Drought has been found to stimulate fine root growth in maize [16]. However, contradictory results were found in drought studies of other species [17,73]. Our study surprisingly found that the inhibition effect of drought on thick roots or fine roots of bamboo was not fixed in different periods.…”

“…The decrease of very fine roots (0.1-0.2 mm) can increase the absorption and penetration ability of roots to dry soil [58,69]. Previous studies have shown that plants respond to the penetration resistance of the uppermost soil layer by reducing the number of lateral and axial roots [70,71], increasing root crown width [72] and root thickness [73], especially for the plants with fibrous roots, such as maize and wheat. Each newly initiated root needs to penetrate the uppermost soil layer to reach lower soil layers to acquire water from deeper soil.…”

Phenotyping and Validation of Root Morphological Traits in Barley (Hordeum vulgare L.)

“…For barley, genotypes with contrasting root size had different grain yield [27]. Root traits such as total root length and total root biomass in the seedling stage were associated with drought tolerance under field conditions in maize, wheat and barley [28]. In the present study, the root mass showed a strong positive correlation with the shoot mass.…”

Effects of biochar amendments on soil water retention characteristics of red soil at south China

“…Zhang and Zhang (1995) also suggested the development of micro-aggregates in red soils which facilitate downward water transfer contributed to the poor water storage efficiency of red soils, and the small amount of water stored in the micro-aggregates is poorly available for biological activity. Building the macro-aggregate and stability of red soils can increase the amount of plant available water, and improve the soil water properties (He et al 2017(He et al , 2019Shi et al 2017). Liu et al (2018) found remarkable increases in macropores high application rate of biochar application, which were contributed by the larger pores between macro-aggregate associated with biochar application.…”