Authors:N. Niu, Y.X. Bai, S. Liu, Q.D. Zhu, Y.L. Song, S.C. Ma, L.J. Ma, X.L. Wang, G.S. Zhang, and J.W. Wang
Studies of the pollen abortion mechanism in thermo-sensitive male sterile lines may provide a strong foundation for breeding hybrid wheat and establishing a theoretical basis for marker-assisted selection. To investigate the cause of pollen abortion in Bainong thermo – sensitive male sterile (BNS) lines, we analyzed the properties of pollen grains, changes in the tapetum and microspores in different anther developmental stages, and the distribution and deposition of nutrient substances in microspores. We found that tapetum degraded in the early uninucleate stage in sterile BNS (S-BNS), which was earlier than that of fertile BNS (F-BNS) tapetum. Large amounts of insoluble polysaccharides, lipids, and proteins were deposited until the trinucleate pollen stage in the nutritive cells in F-BNS. At the binucleate stage, the vacuoles disappeared and pollen inclusion increased gradually. At the trinucleate stage, these nutrients would help pollen grains mature and participate in fertilization normally. Therefore, early degradation of the tapetum, which inhibits normal microspore development, and the limited content of nutrient substances in pollen may be the main factors responsible for male sterility in BNS lines.
The polyamine (PAs), putrescine (Put), spermidine (Spd) and spermine (Spm) are small aliphatic amines that ubiquitous in all living organisms. PA metabolism in higher plants is involved in both biotic and abiotic stress responses, and also influenced by nutrient deficiency. Accumulated evidence suggests that in plants the cellular titers of PAs are affected by various nitrogenous compounds. Therefore, the present study analyzed the effects of different nitrogen levels viz. recommended doses of nitrogen (RDN, 120 kg N/ha), sub-optimal N dose (RDN −25%, 90 kg N/ha) and supra-optimal N dose (RDN +25%, 150 kg N/ha) on PA metabolism in grains of six wheat genotypes at 15 days post anthesis (DPA) and 30 DPA. The activities of polyamine synthesizing enzymes (arginine decarboxylase, ornithine decarboxylase), catabolizing (diamine oxidase, polyamine oxidase) and the PA content were increased at supra-optimal nitrogen dose as compared to RDN. Whereas at sub-optimal nitrogen dose, higher activity of polyamine catabolizing enzymes results in speeding up oxidation of various PAs to cope up with nitrogen deficiency in plant. In relation to PA content, Put was found to be higher at early stage whereas Spd and Spm were found to be higher towards mature stages of grain indicating the use of Put in grain filling process. Highly significant correlation was observed between PA metabolism, yield and nitrogen use efficiency at sub-optimal N dose as compared to supra-optimal dose.
Authors:M. Sheidai, S. Darini, S. M. Talebi, F. Koohdar, and S. Ghasemzadeh-Baraki
The genus Linum L. is an important plant genus as it contains the species with economic values and particularly Linum usitatissimum L. that is source of fibre and linseed oil. This genus contains 230 species throughout the world and has about 22 species in Iran. Little is known about Linum species relationship and phylogeny. Therefore, the aim of present study was molecular phylogenetic investigation of the Linum species growing in Iran and to present data on their biogeography. We used both ITS and chloroplast DNA sequences (psbA-trnHGUG region) for inferring the species phylogeny and relationship. We also used cpDNA for inferring the species time of divergence and with ISSR markers to identify the path of species distribution in the country. The phylogenetic trees obtained for both ITS and cpDNA sequences were almost congruent. NeighborNet diagram and BEAST tree based on Bayesian method separated the outgroup species Hugonia and Anisadenia from the other species studied. The subspecies studied in Linum macronicum were placed close to each other and along with L. corymbulosum comprised a separate clade. The clades obtained showed divergence time between 5–20 mya. The present study revealed that the species of the sect. Linum are monophyletic, while members of the sections Linastrum and Syllinum are intermixed and seem to be paraphyletic.
Authors:M.Z. Islam, M.A. Siddique, N. Akter, M.F.R.K. Prince, M.R. Islam, M. Anisuzzaman, and M.A.K. Mian
Genetic diversity of 28 restorer lines of rice was studied under irrigated condition through Mahalanobis D2 statistics and simple sequence repeat (SSR) banding patterns. The cluster analysis grouped the lines into five clusters. The principal component analysis showed that the first four components with vector values > 1 contributed 76.32% of the total variations. The intra- and inter-cluster distances were the maximum in cluster V (0.86) and between clusters II and V (15.14), respectively. Flag leaf area, plant height, panicle length, five panicle weight, primary branches per panicle and secondary branches per panicle had maximum contribution towards genetic divergence. A total of 24 alleles varied from 2 to 5 with an average of 2.67 alleles per locus were detected for the nine microsatellite markers across 28 lines. The polymorphism information content (PIC) values ranged from 0.12 to 0.71 with an average of 0.29. RM229 was considered as the best markers on the basis of the highest PIC value. Phylogenetic cluster analysis of the SSR data based on distance divided all lines into three groups (A, B and C), whereas the cluster analysis divided these lines into five groups (I, II, III, IV and V). Besides, evaluation of yield contributing traits demonstrated that the restorer lines under the current study possessed a considerable genetic diversity. Potential lines such as BU1IR, China2R, China1R, BHD3R, IR509R and Heera5R can be used as pollen parent in developing new commercial hybrid varieties. Therefore, potential restorer lines need to be conserved in Genebank for future hybrid rice breeding programs.
Authors:S. Y. Kondratyuk, L. Lőkös, E. Farkas, S.-H. Jang, D. Liu, J. Halda, P.-E. Persson, M. Hansson, I. Kärnefelt, A. Thell, Z. Fačkovcová, Y. Yamamoto, and J.-S. Hur
The new for science genus Loekoeslaszloa S. Y. Kondr. et J.-S. Hur, confirmed by three gene phylogeny of the subfamily Teloschistoideae of the Teloschistaceae based on nrITS, nrLSU and mtSSU sequences, and ten new to science species from Eastern Asia, i.e. from South Korea: Bacidina loekoesiana S. Y. Kondr. et J.-S. Hur, Fauriea jejuensis S. Y. Kondr., L. Lőkös et J.-S. Hur, Gyalecta ulleungdoensis S. Y. Kondr., L. Lőkös et J.-S. Hur, Loekoeslaszloa huriana S. Y. Kondr., Orientophila dodongana S. Y. Kondr., L. Lőkös et J.-S. Hur, O. imjadoensis S. Y. Kondr., L. Lőkös et J.-S. Hur, O. incheonensis S. Y. Kondr., L. Lőkös et J.-S. Hur, Oxneriopsis taehaensis S. Y. Kondr., L. Lőkös et J.-S. Hur, Yoshimuria ivanpisutiana S. Y. Kondr., L. Lőkös et J.-S. Hur and Y. seokpoensis S. Y. Kondr., L. Lőkös et J.-S. Hur are described, illustrated and compared with closely related taxa.
Molecular data for the recently described species Flavoplaca laszloana are for the first time provided. Position of Tassiloa magellanica in the subfamily Teloschistoideae as well as Yoshimuria stipitata in the Ikaerioideae ad int. is for the first time illustrated.
An identification key to Fauriea species (including six species, i.e.: F. chujaensis, F. jejuensis, F. orientochinensis, F. patwolseleyae, F. tabidella and F. yonaguniensis), a key to Orientophila species of the Eastern Asian region (of the Orientophila loekoesii and the O. diffluens groups), and a key to Yoshimuria and Loekoeslaszloa species of the Eastern Asian region (including four species, i.e.: Y. galbina, Y. ivanpisutiana, Y. seokpoensis, and Y. spodoplaca, as well as Loekoeslaszloa geumohdoensis and L. huriana) are presented. Seven new combinations, i.e. Fauriea patwolseleyae (basionym: Caloplaca patwolseleyae S. Y. Kondr., U. Jayalal et J.-S. Hur), Fauriea tabidella (basionym: Lecanora tabidella Nyl.), Loekoeslaszloa geumohdoensis (basionym: Mikhtomia geumohdoensis S. Y. Kondr., D. Liu et Hur), Niesslia coarctatae (basionym: Stigmidium coarctatae S. Y. Kondr., L. Lőkös et J.-S. Hur), Opeltia epiphyta (basionym: Caloplaca epiphyta Lynge), Tassiloa magellanica (basionym: Caloplaca magellanica Søchting et Sancho) and Yoshimuria stipitata (basionym: Caloplaca stipitata Wetmore) are proposed. Yoshimuria galbina and Lecanora ussuriensis are for the first time recorded from Japan.
Zoopsidella grahamii sp. nov., related to the Australasian Z. caledonica, is described from the Andes of Central Peru (Oxapampa Province) and southern Ecuador. It is distinguished from Z. caledonica by the smaller plant size, much lower number of lobe cells and different leaf shape, and by the much more elongate perianth mouth lobes consisting of a row of 6-7 narrowly rectangular cells. Riccardia gradsteinii sp. nov., from the same general area in Peru as Z. grahamii, is unique among all dendroid species of the genus by the broad, frilled wings of the main axis, being split into complicatedly bent and strongly crispate scales.
Authors:T. Pócs, N.-K.-T. Tram, Q. He, T. Katagiri, and T.-T. Luong
After the examination of the Cryptogam collection in the Herbarium of the University of Science, Vietnam National University Ho Chi Minh City (PHH), 25 species proved to be new to Vietnam, including one hornwort and 24 liverworts. Among them, four genera: Denotarisia Grolle, Gongylanthus Nees, Leiomitra Lindb. and Lepicolea Dumort. are new records for the country. Diagnostic characters and illustrations are given for some taxa, as well as locality notes and habitat descriptions are provided for each collecting area.
Authors:M. Osman, X. He, F. Capettini, J. Helm, and P.K. Singh
Fungal diseases pose a great challenge to Canadian barley production, among which are Fusarium head blight (FHB), yellow rust and scald. An integrated management approach is needed to mitigate these diseases, in which breeding for host resistance is the most effective component. Constant evaluation of advanced breeding lines for their resistance to the diseases is important for making steady progression. The main objective of this study was to screen 1,174 barley accessions, from a collaborative project between the Field Crop Development Center (FCDC), Alberta, Canada, and the International Maize and Wheat Improvement Center (CIMMYT), Mexico for their reactions to the three diseases. For FHB a 1-5 scale was employed to discard the very susceptible material in 2012 and 2013. In 2014, 514 most resistant lines having the score 1 in 2013 were re-evaluated in a replicated experiment. The most promising 166 genotypes were selected and advanced for their last evaluation in 2015 where FHB index was measured. Simultaneously, these 166 genotypes were subjected to two more experiments to test their reactions against stripe rust and scald. Eighteen two-rowed barley genotypes exhibiting broad-spectrum resistance to all of the three evaluated diseases were identified in addition to 40 lines combining FHB resistance with resistance to Mexican isolates and natural fungal population of either of the two foliar diseases and could be utilized in breeding programs aimed at improving resistance to multiple barley leaf and head blight diseases.
Authors:R. Tabaripour, M. Sheidai, S. M. Talebi, and Z. Noormohammadi
A cogent medicinal and aromatic plant, Ziziphora clinopodioides (Lamiaceae) is a perennial herb, its aerial parts is used as a wild vegetable or additive in foods to proffer pleasant aroma and flavour. There are many discussions about the intraspecific classification of this species and several subspecies have been introduced for it in different flora. These subspecies are morphologically very similar and identification of them is very difficult and in some cases, impossible. Therefore, in the present study, the pollen grains morphology of nine subspecies (32 specimens) of Z. clinopodioides were probed and documented in details utilising the scanning electron microscopy (SEM). In total, eleven pollen morphological characteristics were investigated and analysed by PAST software. The obtained results showed that pollen grains were hexacolpate and their equatorial views were sub-oblate to prolate. The exine ornamentation types of the pollen grains are bireticulate, microreticulate, reticulate and bireticulate-reticulate. The ANOVA test did not show significant difference for the studied quantitative traits. Although, the results of the multivariate analysis revealed a high diversity amongst the specimens even in the specimens of a single subspecies; it did not confirm the separation of subspecies in Z. clinopodioides.
Authors:K. Wajdzik, G. Gołębiowska, M. Dyda, K. Gawrońska, M. Rapacz, and M. Wędzony
The increasing economic importance of triticale (×Triticosecale Wittm.) makes this synthetic hybrid cereal an interesting object of genetic studies. Genomic regions (QTL) of morphological winter triticale traits were determined using the mapping population of 89 doubled haploids lines (DHs) developed from F1 hybrid of cv. ‘Hewo’ and cv. ‘Magnat’ accompanied with the genetic map consisting of 20 linkage groups assigned to the A (7), B (7), and R (6) genomes (total of 3539 DArT, SNP-DArT and SSR markers, length of 4997.4 cM). Five independent experiments were performed in the field and greenhouse controlled conditions. A total of 12 major QTLs located on 2B, 5A, 5R, and 6B chromosomes connected to the stem length, the plant height, the spike length, the number of the productive spikelets per spike, the number of grains per spike, and the thousand kernel weight were identified by a composite interval mapping (CIM).