Roxana Calugar
@scdaturda.ro
Maize breeding
Agricultural Research and Development Station Turda
RESEARCH, TEACHING, or OTHER INTERESTS
Agronomy and Crop Science, Agricultural and Biological Sciences
Scopus Publications
Scholar Citations
Scholar h-index
Scopus Publications
Călin Popa, Roxana Elena Călugăr, Andrei Varga, Edward Muntean, Ioan Băcilă, Carmen Daniela Vana, Ionuț Racz, Nicolae Tritean, Ioana Virginia Berindean, Andreea D. Ona,et al.
MDPI AG
To ensure food and feed security, modern maize hybrids must not only perform well under changing climate conditions but also consistently achieve higher and stable yields, exhibit maximum tolerance to stress factors, and produce high quality grains. In a study conducted in 2022 and 2023, 50 maize hybrids were developed from crosses of five elite (highly productive) inbred lines and ten lines possessing favorable genes for carotenoid content. These hybrids were tested under particularly unfavorable conditions for maize cultivation. The aim was to identify which lines effectively transmit the desired traits to the offspring (general combining ability—GCA), and to identify superior hybrids in terms of productivity, adaptability, and quality (specific combining ability—SCA). The study revealed that total carotenoids ranged from 2.30 to 40.20 μg/g for the inbred lines and from 7.45 to 25.08 μg/g for hybrids. A wider distribution of values was observed in the inbred lines compared to the hybrids for key carotenoids such as lutein, zeaxanthin, β-cryptoxanthin, and β-carotene. Among the hybrids, notable performers in yield, adaptability, and carotenoid content included E390×D302, A452×D302, and A447×D302. The paternal inbred line D302 exhibited a high general combining ability for yield (1446 kg ha−1) and, when crossed with several inbred lines, produced hybrids with enhanced yields and higher levels of zeaxanthin, lutein, and β-carotene, as well as improved unbroken plants percent.
Roxana Elena Călugăr, Andrei Varga, Carmen Daniela Vana, Loredana Ancuța Ceclan, Ionuț Racz, Felicia Chețan, Alina Șimon, Călin Popa, Nicolae Tritean, Florin Russu,et al.
MDPI AG
Maize is affected by drought and heat, abiotic stress factors that have been encountered more often in recent years in various parts of Europe. In the area of Turda, Romania, extreme temperatures and heat waves combined with an uneven distribution of precipitation have been recorded that had an unfavorable influence on the maize crop. In this study, the ASI (anthesis-to-silking interval), yield, and stability of 35 old and new maize hybrids created at the Agricultural Research and Development Station Turda were studied under drought and heat conditions. An increase in temperature was observed during vegetative growth and grain filling, and rainfall was deficient during and after flowering. These conditions had a negative influence on ASI, grain filling, and, indirectly, yield, which varied significantly during the seven experimental years. The five newest hybrids (Turda335, Turda2020, Turda380, Sur18/399, and HST148) stood out, with average yields of over 8400 kg ha−1 in unfavorable years and over 15–16,000 kg ha−1 under favorable conditions. They generally outperformed the mean by 29–33%. In contrast, the old hybrids achieved yields up to 22% lower than the experimental mean. Yield was 43.1% lower in 2022 and 31.8% lower in 2023 compared to the best year (2021).
Zsuzsa Domokos, Alina Șimon, Felicia Chețan, Ovidiu Adrian Ceclan, Emanuela Filip, Roxana Elena Călugăr, Sorin Daniel Vâtcă, and Marcel Matei Duda
MDPI AG
The sowing date of maize significantly impacts its main yield elements. The experiment, conducted at the Research and Development Station for Cattle Breeding (R.D.S.C.B.) Târgu Mureș, Sângeorgiu de Mureș, România, from 2018 to 2021, involved nine maize hybrids from different maturity groups, sown on three dates: early sowing (ES) at 6 °C soil temperature, optimal sowing (OS) at 10 °C soil temperature, and late sowing (LS) two weeks after the optimal date. The experiment was placed in a poly-factorial experience of type: A × B × C × C − R: 3 × 9 × 4 − 3, organized according to the subdivided plots method. The study examined the influence of sowing date on grain yield (GY), thousand-kernel weight (TKW), test weight (TW), percentage of grains per cob (% G/C), and grain humidity at harvest (GHH). The results indicated that yield was not negatively impacted by early or late sowing compared to the optimal date, with differences of 52 kg ha−1 between ES and OS, 147 kg ha−1 between ES and LS, and 95 kg ha−1 between OS and LS. ES increased TW (723.4 kg hl−1) and % G/C (86.7%), but reduced GY (13,377 kg ha−1), TKW (335.3 g), and GHH (19.5%). Conversely, LS positively influenced GY (13,524 kg ha−1), TKW (356.7 g), and GHH (23.9%), but negatively affected TW (692.8 kg hl−1) and % G/C (84.9%). Yield data obtained by P9900 and Kapitolis hybrids suggest that they are suitable for early sowing.
Andrei Varga, Roxana Elena Călugăr, Carmen Vana, Loredana Ceclan, Ionuț Racz, and Nicolae Tritean
MDPI AG
Knowledge of relatedness among maize elite breeding genotypes is useful in planning crosses for hybrid and inbred line improvement and assigning them into heterotic groups. This study investigated phenotypic and genetic similarities or diversities between 7 flint inbred lines (of common origin) adapted to the early maize growing regions created at ARDS Turda-Romania. They were studied for per se traits and in two crossing systems: a diallel crossing system, resulting in 21 hybrids and a cyclic system using four testers, thus resulting in 28 maize hybrids. Both parental inbred lines and hybrids were evaluated for several traits over three years. The level of relatedness/diversity was determined by various methods, grouped into: phenotypic methods and genetic methods. Similarities were identified between certain lines and a degree of differentiation between others. The analysis of the hybrid combinations from the diallel crossings between the seven sister lines highlighted the TD236 inbred line as the only one that differs genetically from the other. Following the analysis of the data obtained in the cyclic system, some inbred lines can be sources of favorable traits: TD236 and TD233 for yield, ear weight, grain/ear weight; TD233 and TD234 for the number of kernels/row, TD237 for plant breaking resistance.
Carmen Daniela VANA, Andrei VARGA, Roxana Elena CALUGAR, Ancuta CECLAN, Nicolae TRITEAN, and Adina TARAU
University of Agronomic Sciences and Veterinary Medicine in Bucharest (UASVMB)
Maize inbred lines derived from local populations (Cycle I lines) were tested using cycle II elite inbred lines. In the cross system, hybrids have a wide variability for yield (6601-10571 kg/ha), the highest differences between hybrids are due to the non-additive genetic effects; undesirable traits transmitted by cycle I inbred lines are weak resistance to stalk breaking and fallen plants; for the percentage of unbroken plants, the genetic variability is high, the percentage of unbroken plants for simple hybrids has a range value between 65.02% and 89.70%.There were calculated the correlations coefficients between ”per se” values for the correlation of inbred lines from crossbreeding system and additive genetic effects values calculated in the crossbreeding system ”m x n”. Positive correlations were identified between the values per se and the positive genetic effects for yield, ear weight, ear length, numbers of kernels per ear, TKW, kernel depth. These high positive correlation values indicate the possibility to use phenotypic markers in the process of inbred lines creation.
Roxana E. CĂLUGĂR, Carmen D. VANA, Andrei VARGA, Loredana A. CECLAN, Nicolae TRITEAN, and Alexandru B. GHEȚE
University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca
Maize is one of the most important crops, both worldwide and in Romania, and preserving the diversity of the biological material used in the breeding of this plant is of particular importance. The Agricultural Research and Development Station (ARDS) Turda, Romania, inbred lines collection includes both its own genotypes and some obtained as a result of germplasm exchanges with other institutions in the country or abroad. In the present study, 575 lines created at Turda were analysed regarding some traits of the plant (plant height, ear height, total number of leaves, number of tassel branches) and the ear (ear length and weight, number of kernel rows and number of kernels/row). The biological material used in this study shows a great diversity: a medium or high variability coefficient was identified for several of the traits analysed (number of tassel branches, ear height, ear height). Frequency histograms were made for the studied lines, for plant and ear traits. A great variability also was observed in the colours of the anther and silk, but also for kernel type and colour and cob colour.
Felicia Cheţan, Teodor Rusu, Roxana Călugăr, Cornel Chețan, Alina Şimon, Adrian Ceclan, Marius Bărdaș, and Olimpia Mintaș
MDPI AG
The experimental zone of the Transylvanian Plain is characterized by some particular problems for the maize crop due to an oscillating thermal regime; relatively shorter frost-free interval; climatic diversity; mixed relief; and soils with different peculiarities, even from one plot to another. This paper presents the results of research conducted during 2016–2021 regarding the influence of four soil tillage system and two fertilizer doses on emergences and maize yield, in the pedoclimatic conditions of the hilly area of the Transylvanian Plain. In all experimental years, a faster maize emergence was observed in the conventional-plow and minimum tillage—chisel compared to minimum tillage-disk and no-tillage. In a conventional system (control), the yield achieved (7603 kg ha−1) was close to the minimum tillage—chisel system (7529 kg ha−1), and higher than the minimum tillage-disk (6391 kg ha−1) and no-tillage (5178 kg ha−1). The beneficial effect of additional fertilization with CAN 27 (granular nitrogen fertilizer containing magnesium and calcium from dolomite) is found in a better development of plants and on the increase of yield with 356 kg ha−1 compared to the variant with basic fertilization. The yield difference between the two hybrids included in the experiment is insignificant (under 100 kg ha−1).
Roxana Elena Calugar, Edward Muntean, Andrei Varga, Carmen Daniela Vana, Voichita Virginia Has, Nicolae Tritean, and Loredana Anca Ceclan
MDPI AG
Carotenoids are important biologically active compounds in the human diet due to their role in maintaining a proper health status. Maize (Zea mays L.) is one of the main crops worldwide, in terms of production quantity, yield and harvested area, as it is also an important source of carotenoids in human nutrition worldwide. Increasing the carotenoid content of maize grains is one of the major targets of the research into maize breeding; in this context, the aim of this study was to establish the influence of some fertile cytoplasm on the carotenoid content in inbred lines and hybrids. Twenty-five isonuclear lines and 100 hybrids were studied for the genetic determinism involved in the transmission of four target carotenoids: lutein, zeaxanthin, β-cryptoxanthin and β-carotene. The analysis of carotenoids was carried out using high performance liquid chromatography using a Flexar system with UV-VIS detection. The obtained data revealed that the cytoplasms did not have a significant influence on the carotenoid content of the inbred lines; larger differences were attributed to the cytoplasm × nucleus interaction. For hybrids, the cytoplasmic nuclear interactions have a significant influence on the content of lutein, zeaxanthin and β-cryptoxanthin. For the cytoplasm × nucleus × tester interactions, significant differences were identified for all traits.
Ioan BĂCILĂ, Voichița HAȘ, Dana ȘUTEU, Mihai MICLĂUȘ, Ana COSTE, Edward MUNTEAN, Carmen D. VANA, Andrei VARGA, Roxana CĂLUGĂR, and Ana COPÂNDEAN
University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca
Maize occupies a significant place in the world agriculture. Yellow kernel maize contains mainly non-provitamin A carotenoids: lutein and zeaxanthin. The accumulation of provitamin A carotenoids is regulated by favourable alleles of lcyE and crtRB1 genes and could be used for the enhancement of these carotenoids in the maize grain through breeding. In this study, molecular screening of the Romanian germplasm was performed, looking for favourable alleles of the crtRB1 and lcyE genes, and the level of carotenoids was determined in a few selected lines. A number of 2746 inbred lines from seven research stations were subjected to a PCR amplification of crtRB1 and lcyE genes in order to identify the favourable alleles. It was selected 27 lines carrying the favourable alleles and nine lines with unfavourable alleles (four groups in total), from which total carotenoids, lutein, zeaxanthin, β-cryptoxanthin, β-carotene and retinol equivalents were determined by HPLC. Out of 2746 inbred lines analysed, 23.53% contained one or both genes with favourable alleles. The favourable allele of the crtRB1 gene was the most widespread (584 lines), followed by the lcyE gene (55 lines), while alleles favourable for both genes were detected in only 7 lines. Inbred lines with the favourable allele of the crtRB1 gene showed the highest levels of β-carotene and β-cryptoxanthin, while those with favourable allele of lcyE gene showed a high level of β-cryptoxanthin; the lines with favourable alleles for both genes had a level of β-carotene 60% higher than the lines with two unfavourable alleles.
Roxana E. Calugar, Voichita V. Has, Andrei Varga, Carmen D. Vana, Ana Copandean, and Ioan Has
Springer Science and Business Media LLC