Association Analysis of Simple Sequence Repeat (SSR) Markers with Agronomic Traits in Tall Fescue (Festuca arundinacea Schreb.)

Abstract

Tall fescue is widely used in temperate regions throughout the world as a dominant forage grass as well as a turfgrass, in pastoral and turf industry. However, the utilization of tall fescue was limited because of its leaf roughness, poor regeneration ability and poor stress resistance. New cultivars were desirable in modern pastoral industries exceed the potential of existing cultivars. Therefore, well understanding the agronomic traits and describing germplasms would help to overcome these constraints, and morphological evaluation of tall fescue germplasm is the key component in selecting rational parents for hybridization breeding. However, describing the morphological traits of tall fescue germplasm is costly and time-consuming. Fortunately, biotechnology approaches can supplement conventional breeding efforts for tall fescue improvement. Association mapping, as a powerful approach to identify association between agronomic traits and molecular markers has been widely used for enhancing the utilization, conservation and management of the tall fescue germplasms. Therefore, in the present research, 115 tall fescue accessions from different origins (25 accessions are cultivars; 31 accessions from America; 32 accessions from European; 7 accessions from Africa; 20 accessions from Asia), were evaluated for agronomic traits and genetic diversity with 90 simple sequence repeat (SSR) markers. The panel displayed significant variation in spike count per plant (SCP) and spike weight (SW). However, BCS performed the lowest CV among all the observed agronomic traits. Three subpopulations were identified within the collections but no obvious relative kinship (K) was found. The GLM model was used to describe the association between SSR and agronomic traits. Fifty-one SSR markers associated with agronomic traits were observed. Twelve single-associated markers were associated with PH; six single-associated markers were associated with BCS; eight single-associated markers were associated with SW; five single-associated markers were associated with SC; seven single-associated markers were associated with SCP; three single-associated markers were associated with SL. Especially, we observed that the genetic variation of SW was explained 11.6 % by M37 marker. It is interesting to observe that nine markers (M1, M2, M35, M54 marker was associated with both BCS and SC; M3, M4 markers were associated with BCS, SW, and SC; M19 marker was associated with both pH and PD, M40 marker was associated with both SCP and SW; and M193 marker was associated with both PH and SL) were associated with more than two agronomic traits. Notably, Branch count per spike (BCS) was explained by four markers (M1, M2, M3, and M4) exceeding 10 %. These identified marker alleles associated with agronomic traits could provide important information and markers for molecular-assisted breeding that facilitate the breeding process in tall fescue.

Marker-trait association analysis for drought tolerance in smooth bromegrass

“…This low R 2 value for each trait may be attributed to the role of many minor genes controlling the trait, outcrossing nature of smooth bromegrass, markers exhibiting minor quantitative effect, rare alleles, and complex allelic interactions [47,48]. These results are in agreement with the findings of Lou et al [32] and Sun et al [33] in tall fescue.…”

Association mapping unveils favorable alleles for grain iron and zinc concentrations in lentil (Lens culinaris subsp. culinaris)

“…Lou et al . [ 120 ] used 90 SSRs for the mapping QTLs for agronomic traits in Fescue. Gyawali et al .…”

Evaluation of molecular diversity analysis and relation with environmental factors in accessions of Cumin (Cuminum cyminum L.) in Iran, revealed by inter-simple sequence repeat (ISSR) markers and start codon targeted (SCoT) markers

“…Generally, in the plant breeding programs and genotype conservation the population structure and genetic diversity information are valuable keys. Agromorphological traits are prerequisite to classify and describe genotype diversity (LOU et al, 2015). In the current study, all agro-morphological traits showed a signi cant difference between the ecotypes (except the number of branches).…”