Plant height in wheat (Triticum aestivum L.) is controlled in large part by two major Rht genes, Rht-B1 and Rht-D1, which pleiotropically impact lodging and grain yield. Prior to the Green Revolution, wheat varieties contained only ‘wild-type’ Rht alleles (Rht-B1a and Rht-D1a) and were tall and prone to lodging. Introgression of a semi-dominant mutation at either of these two loci (Rht-B1b or Rht-D1b) results in a semi-dwarf phenotype and reduced plant height. When combined (Rht-B1b and Rht-D1b) an extremely short double-dwarf phenotype is observed. The objective of this study was to determine the impact of allelic variation in Rht-B1 and Rht-D1 on plant height, grain yield, and yield components in soft red winter wheat (SRWW). A doubled haploid population (n = 98) derived from the lines ‘Neuse’ (Rht-D1 dwarfing) and ‘Bess’ (Rht-B1 dwarfing) segregating at the Rht loci, was evaluated in five total site-years in Arkansas. Analysis of variance across locations showed that allelic variation at the Rht loci significantly affected grain yield, plant height, and yield components (p ≤ 0.05) with no Rht x location interaction. Overall, wild-type lines were taller (87.7 cm) and lower yielding (3.38 t ha-1) compared to semi-dwarf lines. Rht-D1 semi-dwarfs had significantly higher grain yield (3.93 t ha-1) and were shorter (81.4 cm), compared to Rht-B1 lines (3.72 t ha-1 and 83.3 cm). Higher grain yield in Rht-D1 semi-dwarf lines was due in part to significantly higher 1000 kernel weight and kernel weight spike-1, which resulted in higher kernel weight per spike. In addition, seven potential QTL associated with most of the traits measured were identified using a bi-parental approach. In conclusion, future breeding work should focus on the development of Rht-D1 semi-dwarf lines adapted to Arkansas environment.
","abstract_html":"<p>Plant height in wheat (Triticum aestivum L.) is controlled in large part by two major Rht genes, Rht-B1 and Rht-D1, which pleiotropically impact lodging and grain yield. Prior to the Green Revolution, wheat varieties contained only ‘wild-type’ Rht alleles (Rht-B1a and Rht-D1a) and were tall and prone to lodging. Introgression of a semi-dominant mutation at either of these two loci (Rht-B1b or Rht-D1b) results in a semi-dwarf phenotype and reduced plant height. When combined (Rht-B1b and Rht-D1b) an extremely short double-dwarf phenotype is observed. The objective of this study was to determine the impact of allelic variation in Rht-B1 and Rht-D1 on plant height, grain yield, and yield components in soft red winter wheat (SRWW). A doubled haploid population (n = 98) derived from the lines ‘Neuse’ (Rht-D1 dwarfing) and ‘Bess’ (Rht-B1 dwarfing) segregating at the Rht loci, was evaluated in five total site-years in Arkansas. Analysis of variance across locations showed that allelic variation at the Rht loci significantly affected grain yield, plant height, and yield components (p ≤ 0.05) with no Rht x location interaction. Overall, wild-type lines were taller (87.7 cm) and lower yielding (3.38 t ha-1) compared to semi-dwarf lines. Rht-D1 semi-dwarfs had significantly higher grain yield (3.93 t ha-1) and were shorter (81.4 cm), compared to Rht-B1 lines (3.72 t ha-1 and 83.3 cm). Higher grain yield in Rht-D1 semi-dwarf lines was due in part to significantly higher 1000 kernel weight and kernel weight spike-1, which resulted in higher kernel weight per spike. In addition, seven potential QTL associated with most of the traits measured were identified using a bi-parental approach. In conclusion, future breeding work should focus on the development of Rht-D1 semi-dwarf lines adapted to Arkansas environment.</p>","abstract_has_math":false,"creators":["Hayat, Habib"],"institution":null,"degree_name":"Master of Science in Crop, Soil & Environmental Sciences (MS)","degree_level":"Thesis","degree_discipline":null,"degree_department":null,"school":null,"contributors":["Pereira, Andy","Shi, Ainong"],"advisors":["Mason, Richard E."],"committee_chairs":[],"committee_members":[],"year":2018,"date_issued":"2018-08-01T07:00:00Z","date_published":"2018-08-01T07:00:00Z","updated_at":"2026-07-24T01:00:19Z","subjects":["Grain Yield","Green Revolution Genes","Plant Height","QTL Mapping","Rht Loci","Soft Red Winter Wheat","Agronomy and Crop Sciences","Plant Biology","Plant Breeding and Genetics"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://scholarworks.uark.edu/etd/2898","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Pereira, Andy","Shi, Ainong"]},{"key":"dc:contributor.advisor","label":"Advisor","values":["Mason, Richard E."]},{"key":"dc:creator","label":"Author","values":["Hayat, Habib"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2018"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2020-08-03T07:00:00Z"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science in Crop, Soil & Environmental Sciences (MS)"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Grain Yield","Green Revolution Genes","Plant Height","QTL Mapping","Rht Loci","Soft Red Winter Wheat","Agronomy and Crop Sciences","Plant Biology","Plant Breeding and Genetics"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://scholarworks.uark.edu/etd/2898"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Plant height in wheat (Triticum aestivum L.) is controlled in large part by two major Rht genes, Rht-B1 and Rht-D1, which pleiotropically impact lodging and grain yield. Prior to the Green Revolution, wheat varieties contained only ‘wild-type’ Rht alleles (Rht-B1a and Rht-D1a) and were tall and prone to lodging. Introgression of a semi-dominant mutation at either of these two loci (Rht-B1b or Rht-D1b) results in a semi-dwarf phenotype and reduced plant height. When combined (Rht-B1b and Rht-D1b) an extremely short double-dwarf phenotype is observed. The objective of this study was to determine the impact of allelic variation in Rht-B1 and Rht-D1 on plant height, grain yield, and yield components in soft red winter wheat (SRWW). A doubled haploid population (n = 98) derived from the lines ‘Neuse’ (Rht-D1 dwarfing) and ‘Bess’ (Rht-B1 dwarfing) segregating at the Rht loci, was evaluated in five total site-years in Arkansas. Analysis of variance across locations showed that allelic variation at the Rht loci significantly affected grain yield, plant height, and yield components (p ≤ 0.05) with no Rht x location interaction. Overall, wild-type lines were taller (87.7 cm) and lower yielding (3.38 t ha-1) compared to semi-dwarf lines. Rht-D1 semi-dwarfs had significantly higher grain yield (3.93 t ha-1) and were shorter (81.4 cm), compared to Rht-B1 lines (3.72 t ha-1 and 83.3 cm). Higher grain yield in Rht-D1 semi-dwarf lines was due in part to significantly higher 1000 kernel weight and kernel weight spike-1, which resulted in higher kernel weight per spike. In addition, seven potential QTL associated with most of the traits measured were identified using a bi-parental approach. In conclusion, future breeding work should focus on the development of Rht-D1 semi-dwarf lines adapted to Arkansas environment.
"]},{"key":"dc:title","label":"Title","values":["Effect of Allelic Variation in Rht Loci on Plant Height and Grain Yield of Soft Red Winter Wheat (Triticum aestivum L.)"]}]}],"canonical_facts":{"dc:contributor":["Pereira, Andy","Shi, Ainong"],"dc:contributor.advisor":["Mason, Richard E."],"dc:creator":["Hayat, Habib"],"dc:date":["2018"],"dc:date.available":["2020-08-03T07:00:00Z"],"dc:description.abstract":["Plant height in wheat (Triticum aestivum L.) is controlled in large part by two major Rht genes, Rht-B1 and Rht-D1, which pleiotropically impact lodging and grain yield. Prior to the Green Revolution, wheat varieties contained only ‘wild-type’ Rht alleles (Rht-B1a and Rht-D1a) and were tall and prone to lodging. Introgression of a semi-dominant mutation at either of these two loci (Rht-B1b or Rht-D1b) results in a semi-dwarf phenotype and reduced plant height. When combined (Rht-B1b and Rht-D1b) an extremely short double-dwarf phenotype is observed. The objective of this study was to determine the impact of allelic variation in Rht-B1 and Rht-D1 on plant height, grain yield, and yield components in soft red winter wheat (SRWW). A doubled haploid population (n = 98) derived from the lines ‘Neuse’ (Rht-D1 dwarfing) and ‘Bess’ (Rht-B1 dwarfing) segregating at the Rht loci, was evaluated in five total site-years in Arkansas. Analysis of variance across locations showed that allelic variation at the Rht loci significantly affected grain yield, plant height, and yield components (p ≤ 0.05) with no Rht x location interaction. Overall, wild-type lines were taller (87.7 cm) and lower yielding (3.38 t ha-1) compared to semi-dwarf lines. Rht-D1 semi-dwarfs had significantly higher grain yield (3.93 t ha-1) and were shorter (81.4 cm), compared to Rht-B1 lines (3.72 t ha-1 and 83.3 cm). Higher grain yield in Rht-D1 semi-dwarf lines was due in part to significantly higher 1000 kernel weight and kernel weight spike-1, which resulted in higher kernel weight per spike. In addition, seven potential QTL associated with most of the traits measured were identified using a bi-parental approach. In conclusion, future breeding work should focus on the development of Rht-D1 semi-dwarf lines adapted to Arkansas environment.
"],"dc:identifier":["https://scholarworks.uark.edu/etd/2898"],"dc:subject":["Grain Yield","Green Revolution Genes","Plant Height","QTL Mapping","Rht Loci","Soft Red Winter Wheat","Agronomy and Crop Sciences","Plant Biology","Plant Breeding and Genetics"],"dc:title":["Effect of Allelic Variation in Rht Loci on Plant Height and Grain Yield of Soft Red Winter Wheat (Triticum aestivum L.)"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["Master of Science in Crop, Soil & Environmental Sciences (MS)"]},"updated_at":"2026-07-24T01:00:19Z"}