https://repository.utm.md/handle/5014/15 Mon, 27 Jul 2026 18:57:49 GMT 2026-07-27T18:57:49Z https://repository.utm.md/handle/5014/36915 Assessment of doubled haploid production efficiency in maize using sequential phenotypic marker screening BATÎRU, Grigorii; COJOCARI, Dumitru; BOUNEGRU, Serghei; MOCREAC, Nadejda; COMAROVA, Galina Doubled haploid (DH) technology has become an important tool for accelerating maize breeding by enabling the rapid development of completely homozygous lines. However, breeding decisions depend not only on haploid induction rate or chromosome doubling success, but also on the cumulative efficiency of the entire DH pipeline. Despite its practical importance, information on material losses from induced seed to recovered DH line remains limited under routine breeding conditions. The aim of this study was to assess the efficiency of doubled haploid production in maize by quantifying material losses across successive stages of haploid induction, phenotypic selection, chromosome doubling, and final recovery of fertile DH lines. Fifty genetically diverse maize donor populations were pollinated with a maternal haploid inducer carrying the dominant phenotypic markers R1-nj and Pl1. Putative haploid seeds were initially identified using the R1-nj anthocyanin marker, followed by secondary validation using the Pl1 root pigmentation marker. A total of 38,916 seeds were evaluated, of which 5,870 putative haploids were identified at the first screening stage, corresponding to a putative haploid selection rate of 15.08%. Secondary screening reduced this number to 3,316 putative haploids (8.52%). Following chromosome doubling, field evaluation, fertility screening, and the removal of non-uniform and electrophoretically segregating ears, 213 fertile putative DH0 ears were retained, resulting in a final operational recovery efficiency of 0.55%. Seed storage protein electrophoresis of well-filled ears confirmed the genetic uniformity of selected DH lines, while low-seed DH0 ears were retained as putative lines requiring further progeny evaluation for full confirmation. The results demonstrate that sequential phenotypic marker screening improves haploid identification accuracy and provide practical estimates of operational losses across the DH pipeline under applied breeding conditions. Thu, 01 Jan 2026 00:00:00 GMT https://repository.utm.md/handle/5014/36915 2026-01-01T00:00:00Z https://repository.utm.md/handle/5014/36914 Dinamica structurii arboretelor rezervației naturale silvice „Copanca” în perioada 2001-2023 CHETREAN, Alexandru Scopul rezervațiilor naturale constă în protejarea și restabilirea componentelor esențiale ale naturii pentru zona dată, în special ecosistemele forestiere, pentru menținerea echilibrului ecologic și prezervarea biodiversităţii. Rezervația naturală silvică „Copanca” este situată în etajul fitoclimatic de silvostepă, astfel ar trebui să fie dominată de arborete de tip natural fundamentale, caracteristice zonei date. Articolul prezintă dinamica modificării structurii arboretelor din cadrul rezervației pe parcursul a 25 de ani, având ca bază descrierile parcelare ale Amenajamentelor OS Talmaza 2001, 2013 și 2023. Articolul atenționează asupra proporției reduse a arboretelor de tip natural fundamental în cadrul rezervației, în pofida arboretelor provizorii de salcâm. Se atenționează asupra sporirii vârstei medii a arboretelor provizorii în rezervație și acumulării suprafețelor de arborete cu salcâm în curs de uscare. Articolul dezvăluie unele cauze ce au influențat asupra acumulării pe decenii în creștere a salcâmetelor în curs de uscare, dar propune și unele soluții privind ameliorarea structurii arboretelor din cadrul rezervației.; The purpose of natural reserves is to protect and restore essential components of nature for the given area, particularly forest ecosystems, to maintain ecological balance and preserve biodiversity. The „Copanca” Forest Natural Reserve is located in the phytoclimatic zone of the forest-steppe, and thus it should be dominated by fundamental natural-type stands characteristic of the area. The article presents the dynamics of changes in the structure of the stands within the reserve over 25 years, based on the parcel descriptions from the OS Talmaza Management Plans of 2001, 2013, and 2023. It draws attention to the increasing average age of temporary stands in the reserve and the accumulation of areas with acacia stands in the process of drying out. The article reveals some causes that have contributed to the decades-long increase in drying acacia stands and proposes solutions to improve the structure of the stands within the reserve. Wed, 01 Jan 2025 00:00:00 GMT https://repository.utm.md/handle/5014/36914 2025-01-01T00:00:00Z https://repository.utm.md/handle/5014/36913 Asociația Geranio pratensi–Cirsietum cani Pînzaru, Ionița et Jardan 2019 (filipendulion segal ex westhaff et den held 1969) în rezervația peisagistică „Dobruşa”, Republica Moldova SFECLĂ, Victor; PÎNZARU, Pavel Ca rezultat al cercetărilor efectuate în cadrul rezervației peisagistice „Dobrușa”, au fost descrise 5 relevee fitocenologice ce aparțin la asociația Geranio pratensi–Cirsietum cani Pînzaru, Ionița et Jardan 2019. Aceste fitocenoze vegetează pe soluri umede în valea râului Ciorna, la altitudine de 174-185 m. Acoperirea generală a învelișului ierbos este 100%. În structura verticală a fitocenozelor se observă 3 straturi, cel superior atinge înălțimea de 170-200 cm. Specii edificatoare sunt Cirsium canum (L.) All., Geranium pratense L. şi Inula helenium L. Specii constante: Eupatorium cannabinum L. (V), Potentilla reptans L. (V), Glechoma hederacea L. (V), Epilobium hirsutum L. (IV), Lythrum salicaria L. (IV), Lysimachia vulgaris L. (IV), Mentha longifolia (L.) Huds. (IV), Valeriana officinalis L. (IV). Specii rare: Caltha palustris L., periclitată (EN) inclusă în Cartea Roșie a Republicii Moldova; Galium rivale (Sibth. & Sm.) Griseb. vulnerabilă (VU); Sonchus palustris L., vulnerabilă (VU) și Selinum carvifolia (L.) L., periclitată (EN); As a result of the research, which was carried out within the landscape reserve „Dobrusa”, 5 phytocenological relevés, which belong to the association Geranio pratensi–Cirsietum cani Pînzaru, Ionița et Jardan 2019, have been described. This phytocenosis vegetate on wet soils, in the Ciorna river valley, altitude of 174-185 m. The overall grasscover is 100%. Three layers can be observed in the vertical structure, the upper one reaches the height of 170200 cm. Edifying species are: Cirsium canum (L.) All., Geranium pratense L. şi Inula helenium L. Constant species are: Eupatorium cannabinum L. (V), Potentilla reptans L. (V), Glechoma hederacea L. (V), Epilobium hirsutum L. (IV), Lythrum salicaria L. (IV), Lysimachia vulgaris L. (IV), Mentha longifolia (L.) Huds. (IV), Valeriana officinalis L. (IV). Rare species are: Caltha palustris L., endangered (EN); Galium rivale (Sibth. & Sm.) Griseb. vulnerable (VU); Sonchus palustris L., vulnerable (VU) și Selinum carvifolia (L.) L., endangered (EN). Mon, 01 Jan 2024 00:00:00 GMT https://repository.utm.md/handle/5014/36913 2024-01-01T00:00:00Z https://repository.utm.md/handle/5014/36912 Biological and pest control characteristics in sugar beet cultivation and economic efficiency analyses based on budgeting PANUȚA, Sergiu; CROITORU, Nichita; ZBANCĂ, Andrei The experiments to determine the biological efficiency of the Boxer Starker preparation were carried out in 2024, in accordance with the program and the cooperation agreement between the State Center for Certification and Approval of Phytosanitary Products and the Technical University of Moldova. The report includes data on the current state of sugar beet protection, the need to carry out scientific work related to testing new preparations is argued. The report includes the scheme of the experiments, the name of the variants and their content, the characteristics of the pedoclimatic conditions during the testing work, budget planning and analyze of efficiency, the results obtained, conclusions and recommendations. To study the influence of abiotic factors on beneficial and harmful organisms, weather station data for 2024 were analyzed. The weather conditions were favorable both for the growth and development of sugar beet plants, and for the spread and development of the main pests of this crop. Wed, 01 Jan 2025 00:00:00 GMT https://repository.utm.md/handle/5014/36912 2025-01-01T00:00:00Z