TY - BOOK

T1 - Exploiting Genetic Diversity in Potato (Solanum tuberosum) to Overcome Soil Constraints to Tuber Yields

AU - Skilleter, Patrick

PY - 2023/8/21

Y1 - 2023/8/21

N2 - Potato fields are highly susceptible to soil compaction, with two-thirds of UKfields severely affected. Compacted soils impede root growth and decreasecrop yields. This thesis’s goal was to identify ways to improve potato yields incompacted soil.Genotypic diversity in compaction tolerance was determined by growing sixpotato cultivars in loose and compacted soil in containers. Compacted soildelayed emergence, reduced leaf area and root length, and increased rootdiameter differently between cultivars. When cultivars varying in compactiontolerance were reciprocally grafted, rootstock affected leaf area and root growthmore than the scion, indicating the root system’s importance.Root production of, and sensitivity to, ethylene were measured in cultivars thatshowed high (Charlotte), intermediate (Maris Piper), and low (Pentland Dell)sensitivity to soil compaction. Soil compaction and cultivar did not affect rootethylene evolution. Exogenous ethylene increased root diameter of Maris Piperand Charlotte similarly, but Pentland Dell was unresponsive. Applying ACCdeaminase-containing rhizobacteria lowered root ethylene evolution of MarisPiper roots and increased root growth in compacted soil to comparable levelsas roots in uncompacted soil. Thus, variation in ethylene production andethylene sensitivity mediate root growth in compacted soil.Two cultivars with higher (Inca Bella) or lower (Maris Piper) sensitivity to soilcompaction were grown in field trials comparing compacted and uncompactedsoil. Irrespective of initial soil resistance, soil resistance consistently increasedto cultivar-dependent maxima during the growing season. Compacted soildecreased Inca Bella yields, but not Maris Piper yields. Inca Bella bettermaintained shoot growth whilst Maris Piper root growth was unaffected bycompaction. Thus, maintaining root growth is more important for maintainingyields in compacted soil produced by pressure on the soil surface.ivThis thesis is the first to identify compaction- and cultivar-dependent changes in soil resistance in potato fields, and to utilise ACC deaminase-containingrhizobacteria to enhance potato tolerance to compaction.

AB - Potato fields are highly susceptible to soil compaction, with two-thirds of UKfields severely affected. Compacted soils impede root growth and decreasecrop yields. This thesis’s goal was to identify ways to improve potato yields incompacted soil.Genotypic diversity in compaction tolerance was determined by growing sixpotato cultivars in loose and compacted soil in containers. Compacted soildelayed emergence, reduced leaf area and root length, and increased rootdiameter differently between cultivars. When cultivars varying in compactiontolerance were reciprocally grafted, rootstock affected leaf area and root growthmore than the scion, indicating the root system’s importance.Root production of, and sensitivity to, ethylene were measured in cultivars thatshowed high (Charlotte), intermediate (Maris Piper), and low (Pentland Dell)sensitivity to soil compaction. Soil compaction and cultivar did not affect rootethylene evolution. Exogenous ethylene increased root diameter of Maris Piperand Charlotte similarly, but Pentland Dell was unresponsive. Applying ACCdeaminase-containing rhizobacteria lowered root ethylene evolution of MarisPiper roots and increased root growth in compacted soil to comparable levelsas roots in uncompacted soil. Thus, variation in ethylene production andethylene sensitivity mediate root growth in compacted soil.Two cultivars with higher (Inca Bella) or lower (Maris Piper) sensitivity to soilcompaction were grown in field trials comparing compacted and uncompactedsoil. Irrespective of initial soil resistance, soil resistance consistently increasedto cultivar-dependent maxima during the growing season. Compacted soildecreased Inca Bella yields, but not Maris Piper yields. Inca Bella bettermaintained shoot growth whilst Maris Piper root growth was unaffected bycompaction. Thus, maintaining root growth is more important for maintainingyields in compacted soil produced by pressure on the soil surface.ivThis thesis is the first to identify compaction- and cultivar-dependent changes in soil resistance in potato fields, and to utilise ACC deaminase-containingrhizobacteria to enhance potato tolerance to compaction.

U2 - 10.17635/lancaster/thesis/2092

DO - 10.17635/lancaster/thesis/2092

M3 - Doctoral Thesis

PB - Lancaster University

ER -