Variation between glaucous and non-glaucous near-isogenic lines of rye (Secale cereale L.) under drought stress

Abstract Glaucous (811, L35, and RXL10) and non-glaucous (811bw, L35bw, and RXL10bw) near-isogenic lines (NILs) of rye (Secale cereale L.) forming three pairs of inbred lines were the subject of the research. The research aimed to study the relationship between wax cover attributes and the physio-biochemical drought reactions and yield of rye NILs and to uncover the differences in drought resistance levels of these lines. The greatest differences between glaucous and non-glaucous NILs were observed in the RXL10/RXL10bw pair. Of particular note were the stable grain number and the thousand grain weight of the non-glaucous line RXL10bw under drought and the accompanying reactions, such as an approximately 60% increase in MDA and a two-fold increase in wax amount, both of which were significantly higher than in the glaucous line RXL10 and in other NILs. The surprisingly high level of MDA in the RXL10bw line requires further analysis. Moreover, additional wax crystal aggregates were found under drought conditions on the abaxial leaf surface of the glaucous lines 811 and RXL10. The use of rye NILs indicated that line-specific drought resistance could be associated with wax biosynthetic pathways involved in physiological and biochemical responses important for increased drought resistance

Comparative characteristics of oat doubled haploids and oat × maize addition lines: Anatomical features of the leaves, chlorophyll a fluorescence and yield parameters.

As a result of oat (Avena sativa L.) × maize (Zea mays L.) crossing, maize chromosomes may not be completely eliminated at the early stages of embryogenesis, leading to the oat × maize addition (OMA) lines development. Introgression of maize chromosomes into oat genome can cause morphological and physiological modifications. The aim of the research was to evaluate the leaves' anatomy, chlorophyll a fluorescence, and yield parameter of oat doubled haploid (DH) and OMA lines obtained by oat × maize crossing. The present study examined two DH and two disomic OMA lines and revealed that they differ significantly in the majority of studied traits, apart from: the number of cells of the outer bundle sheath; light energy absorption; excitation energy trapped in PSII reaction centers; and energy dissipated from PSII. The OMA II line was characterized by larger size of single cells in the outer bundle sheath and greater number of seeds per plant among tested lines

Characterising Biological and Physiological Drought Signals in Diverse Parents of a Wheat Mapping Population

Water deficit affects the growth as well as physiological and biochemical processes in plants. The aim of this study was to determine differences in physiological and biochemical responses to drought stress in two wheat cultivars—Chinese Spring (CS) and SQ1 (which are parents of a mapping population of doubled haploid lines)—and to relate these responses to final yield and agronomic traits. Drought stress was induced by withholding water for 14 days, after which plants were re-watered and maintained until harvest. Instantaneous gas exchange parameters were evaluated on the 3rd, 5th, 10th, and 14th days of seedling growth under drought. After 14 days, water content and levels of chlorophyll a+b, carotenoids, malondialdehyde, soluble carbohydrates, phenolics, salicylic acid, abscisic acid (ABA), and polyamines were measured. At final maturity, yield components (grain number and weight), biomass, straw weight, and harvest index were evaluated. Physiological and biochemical parameters of CS responded more than those of SQ1 to the 14-day drought, reflected in a greater reduction in final biomass and yield in CS. Marked biochemical differences between responses of CS and SQ1 to the drought were found for soluble carbohydrates and polyamines. These would be good candidates for testing in the mapping population for the coincidence of the genetic control of these traits and final biomass and yield

Leaf anatomical traits of DH and OMA lines and <i>cv</i>. Bingo.

The mean values (n = 5) ± SE marked with different letters are significantly different at p ≤ 0.05 according to the Duncan’s multiple test.</p

Chlorophyll <i>a</i> fluorescence kinetics parameters of the DH and OMA lines and cv. Bingo leaves.

(A) Fv/Fm—maximum photochemical efficiency of PSII; (B) Area—area over the chlorophyll a fluorescence induction curve; (C) PI—overall performance index of PSII photochemistry; (D) ABS/CS—light energy absorption; (E) TR0/CS—excitation energy trapped in PSII reaction centers; (F) ET0/CS—energy used for electron transport; (G) DI0/CS—energy dissipated from PSII; (H) RC/CS0—number of active reaction centers in the excited leaf fragment. The mean values (n = 5) ± SE marked with different letters are significantly different at p ≤ 0.05 according to the Duncan’s multiple test.</p

Characteristics of the plant material used in the study.

Characteristics of the plant material used in the study.</p

Identification of maize (<i>Zea maize</i> L.) chromatin added to the oat (<i>Avena sativa</i> L.) genome by PCR and genomic <i>in situ</i> hybridization (GISH).

(A) The agarose gel with bands representing DNA fragments Grande 1 (500 bp) specific for maize; path 1 –marker leader, path 2 –maize cv. Waza, path 3 –oat cv. Bingo, paths 4–13 DH lines of oat, paths 14–15 OMA lines, path 16 DH line of oat (B) Chromosomes of doubled haploid line (DH I), (C) Chromosomes of oat × maize addition line (OMA I). Blue fluorescence: DAPI, green fluorescence: maize genomic DNA (gDNA).</p

One-way analysis of variance for morphological traits and yield components of DH and OMA lines and <i>cv</i>. Bingo.

One-way analysis of variance for morphological traits and yield components of DH and OMA lines and cv. Bingo.</p

Means of data from measurements of leaf anatomical traits, parameters of chlorophyll <i>a</i> fluorescence kinetics, and yield components.

Means of data from measurements of leaf anatomical traits, parameters of chlorophyll a fluorescence kinetics, and yield components.</p

One-way analysis of variance for chlorophyll <i>a</i> fluorescence kinetics parameters of DH and OMA lines and <i>cv</i>. Bingo.

Fv/Fm—maximum photochemical efficiency of PSII; Area—area over the chlorophyll a fluorescence induction curve; PI—overall performance index of PSII photochemistry; ABS/CS—light energy absorption; TR0/CS—excitation energy trapped in PSII reaction centers; ET0/CS—energy used for electron transport; DI0/CS—energy dissipated from PSII; RC/CS0—number of active reaction centers.</p