Most species of the genus Lophopyrum LUve (Agropyron Geartn.) grow in saline environments and are more tolerant of saline stress than the species of the related genus Triticum L. A 56-chromosome amphiploid from the cross Triticum aestivum cv. Chinese Spring x Lophopyrum elongatum exceeded Chinese Spring in salt tolerance, measured as plant dry-matter production and seed yield in solution cultures with 250 mM NaCl. Thus, the adaptation of Lophopyrum to saline environments is expressed in the wheat genetic background. None of the disomic additions or substitutions of L. elongatum chromosomes in Chinese Spring showed a similar level of saline stress tolerance, which indicates that the trait depends on the activity of genes on more than one chromosome. Comparisons of disomic additions, double monosomic additions from half-diallel crosses among disomic additions, and disomic substitutions of L. elongatum chromosomes in Chinese Spring with Chinese Spring indicated that the enhanced salt tolerance of the amphiploid is primarily controlled by genes with minor effects on three of the seven chromosomes, 3E, 4E, and 7E, interacting in a largely additive manner. The salt tolerance of L. elongatum additionally depends on several minor nonadditive gene interactions. It is concluded that the adaptation of L. elongatum to growth in saline environments evolved by accumulation of new alleles in a number ofloci, each with a relatively small effect on salt tolerance. It is further inferred that most of these new alleles were codominant to the original alleles and were able to act independently in enhancing salt tolerance.Most species of the genus Lophopyrum Love (syn. Elytrigia Desv. but originally classified as Agropyron Geartn.) occur naturally in saline environments, either in the littoral zone or in saline soils, and are tolerant of salinity (1, 2). Lophopyrum can be hybridized with the relatively salt-sensitive wheat Triticum aestivum L. (2n = 6x = 42, genomes AA BB DD). This provides an exciting possibility of cytogenetically partitioning the genome of a salt-tolerant species into individual chromosomes, chromosome arms, and chromosome segments in the background of the relatively salt-sensitive wheat and determining the genetic basis of the adaptation to growth under saline stress.An octoploid amphiploid (2n = 8x = 56) from a cross, T. aestivum cv. Chinese Spring x Lophopyrum elongatum (2n = 2x = 14, genomes EE) was shown to have enhanced salt tolerance relative to the parental Chinese Spring (3), indicating that the gene system controlling the adaptation of L. elongatum to saline stress is expressed in the wheat genetic background. Each of the seven L. elongatum chromosome pairs has been added to and substituted for the T. aestivum homeologous chromosomes (4-7). This material was used in the present study to investigate the chromosomal control of the enhanced salt tolerance of the amphiploid with the objective of determining the genetic basis of the adaptation of L. elongatum to growth in saline environments. After 5...
The cotyledonary node tissue culture system stimulates the genesis of shoots from newly formed and pre‐existing meristematic regions of nodal tissue cultured on media containing benzyladenine (BA). The intent of this study was to determine whether soybean (Glycine max L. Merr.) cultivars differ in their response to this system, and to test for the presence of tissue culture derived genetic variants. The response of three soybean cultivars (Calland, Funman, and Wayne) to this system was analyzed. Slight, but statistically significant, differences were observed in shoots per seed, plants per seed, and regeneration time. The number of shoots derived from a given seed after 6 weeks in culture was not correlated with the number of plants ultimately derived from the same seed. Field analysis of progeny of regenerated plants demonstrated no variability for lodging and maturity among seven families. Variability for yield was observed in 2 of 19 families compared to control cultivars. One of 22 families exceeded the control in height, and variability for height was increased among regenerated families. Recessive mutations for putative sterility characters were observed in 2 of 89 families, but mutations in six marker genes were not apparent.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.