Quantitative Trait Loci and Candidate Genes Associated with Cold-Acclimation and Microdochium nivale Tolerance/Susceptibility in Winter Triticale (x Triticosecale)

Tolerance to pink snow mold caused by Microdochium nivale appears after a cold-hardening period and it is an essential, genotype-dependent, complex quantitative trait for the wintering of triticale (x Triticosecale) and other cereals. Despite long-term studies, a marker for the selection of the tolerant genotypes is still insufficiently recognized. Chlorophyll fluorescence has been reported as a sensitive indicator of stress effects on photosynthesis and can be used to predict plant tolerance. In this study, the genomic regions (QTLs) associated with the level of winter triticale seedlings damage caused by M. nivale infection as well as photosynthesis quantum efficiency and chlorophyll a fluorescence parameters were identified in seedlings of mapping population of 89 doubled haploids lines (DHs) derived from F1 hybrid of cv. ‘Hewo’ and cv. ‘Magnat’ accompanied with the genetic map consisting of 20 linkage groups with a total map length 4997.4 cm. Independent experiments performed in controlled conditions revealed 13 regions identified by a composite interval mapping, located on 7A, 1B, 2B, 6B, 7B, 3R, 5R, and 6R linkage groups and related to the PI, PIABS, TRo/CS, ABS/CS, ABS/CSm, ABS/RC, and Qy values as well as M. nivale tolerance T and susceptibility level P expressed by the seedling damage index. Additionally, candidate genes were in silico identified with the sequence position on wheat (2B and 7B) and rye (5R) chromosomes, where relevant QTL regions were found. The most important candidate genes indicated for M. nivale tolerance of cold-hardened triticale seedlings include those coding: sterol 3-beta-glucosyltransferase UGT80A2-like, transcription factor NAI1-like, and flavonol3-sulfotransferase-like proteins on chromosomes 2B and 5R.

New triticale varieties of the BC Institute

Pšenoraž (X Triticosecale Witt.) ili tritikale je vrsta strnih žitarica nastala križanjem pšenice i raži. Pšenoraž se u proizvodnji pojavljuje u drugoj polovici dvadesetog stoljeća. Zbog svojih bioloških svojstava i napretka u selekciji areal uzgoja i proizvodne površine pšenoraži povećavaju se iz godine u godinu. Zadnjih godina u svijetu se pšenoraž sije na preko 4 000 000 ha, a najveći proizvođači su Poljska, Njemačka i Francuska. U Republici Hrvatskoj se proizvodnja pšenoraži unazad nekoliko godina višestruko povećala, a trenutno se sije na preko 15 000 ha. U proizvodnji su prisutne ozime, fakultativne i jare forme pšenoraži. Rad na oplemenjivanju pšenoraži u Bc Institutu pokrenut je početkom 1990-ih godina. Prva ozima sorta pšenoraži Bc Goran priznata je 2004. godine te je trenutno najzastupljenija sorta u Republici Hrvatskoj. Kontinuitet uspješnog oplemenjivanja potvrđen je priznavanjem ozime sorte Bc Ranko 2010. godine, a nastavljen 2019. godine priznavanjem sorata Bc Trenk i Bc Zmaj. Bc Trenk je ozima sorta rane vegetacije, niske stabljike te odlične otpornosti na bolesti pšenoraži. Bc Zmaj je fakultativna sorta, vrlo rane vegetacije, niske stabljike te također dobre otpornosti na bolesti pšenoraži. Prema rezultatima Komisije za priznavanje sorata Republike Hrvatske u dvogodišnjem ispitivanju Bc Trenk je ostvario 24,2%, a Bc Zmaj 15,6% veći urod zrna u odnosu na standardnu sortu.

Nanopartículas de quitosano mejoran la calidad nutracéutica de germinados de triticale

El uso de nanopartículas de quitosán (NPs CS) se ha vuelto una alternativa prometedora en la agricultura moderna como un inductor en la biosíntesis de metabolitos secundarios. El objetivo del presente trabajo fue evaluar el efecto de NPs CS en la calidad nutraceútica de germinados de triticale (x Triticosecale Wittmack). Dosis creciente de NPs CS: 0, 0.1, 0.2, 0.4 y 0.8 mg ml-1 se aplicaron una sola vez en la etapa de imbibición, después se dejaron en cajas Petri durante 7 días a 25 ±2 °C de temperatura. Las NPs CS no afectaron la germinación ni el peso freso de la raíz a las concentraciones probadas, y a la concentración de 0.1 mg ml-1 aumentó el peso fresco del brote hasta 83.3%. En presencia de 0.8 mg ml-1 de las NPs CS los compuestos fenólicos disminuyen un 7% y aumentan 29% los flavonoides. Los resultados confirman un efecto promotor de las NPS CS en los germinados, abriendo la posibilidad de ser utilizadas como inductores en la biosíntesis de compuestos bioactivos en germinados de triticale.

Use of cluster analysis and analysis of the main components for evaluation of triticale samples

The study was conducted in the period 2015-2017 in the experimental field of IRGR "K. Malkov” Sadovo. The elements of productivity of 24 varieties and lines of triticale (X. Triticosecale Wittmacks) were studied. The degree of variation of each of the indicators of productivity is determined by calculating a coefficient of variation. The results obtained show that the most variable indicator is the weight of grains in the central spike whereas the slightest variation is observed in the parameters of test weight and 1000 grains weight. Hierarchical cluster analysis and analysis of the main components (PC-analysis) are applied to assess the genetic similarity and distance between the different varieties. As a result of the clustering the studied samples were divided into six groups. The varieties Trit 32/6 and KS 60 are characterized with the greatest genetic proximity, followed by line BGR 30071 with the Bulgarian variety Rozhen. The largest genetic difference was reported between line BGR 30816 and variety KT 81. The applied analysis of the main components shows that the components PC 1, PC 2 and PC 3 explain 70.6% of the total variation of all traits by genotypes. The largest numbers of samples (9) belong to component 3, as four of them are located in the negative values of PC 3, and the other five genotypes are in the positive values of PC 3. Component 1 is represented by eight samples, and component 2 includes seven triticale genotypes.