Facultatea de Biologie și Geoştiinţe / Faculty of Biology and Geosciences

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End date: 2021Subject: search.filters.subject.floarea-soarelui

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    MANAGEMENTUL CULTURII DE FLOAREA-SOARELUI ÎN GOSPODĂRIILE AGRICOLE DIN REPUBLICA MOLDOVA
    (Academia de Ştiinţe a Moldovei, 2021) Duca, Maria; Clapco, Steliana; Burcovschi, Ion
    In the Republic of Moldova, the oilseed crop sunflower (Helianthus annuus L.) occupies consistent cultivation areas (about 25 % of arable land), which is constantly growing. Trends in agricultural systems from recent decades (intensification and specialization of production), associated with intensive use of agrochemicals (pesticides and fertilizers), irrational land use, non-compliance with crop rotations etc. have led to declining soil quality, biodiversity loss, a significant increase in the incidence of diseases and pests and the vulnerability of agricultural ecosystems to climate change. In order to address the principles of sustainable and ecological agriculture, it is interesting to know in depth the current situation of biotechnologies for sunflower cultivation and the incidence and severity of pathogen attack. This paper reflects the results of analyzes conducted based on farmers’ opinion survey, focused mainly on parameters such as areas cultivated with sunflower, types of cultivated hybrids, geographical distribution of sunflower-specific pathogens, applied agricultural practices etc.
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    FACTORI DE MEDIU ASOCIAȚI CU INCIDENŢA PATOGENILOR LA CULTURA DE FLOAREA-SOARELUI
    (CEP USM, 2021) Duca, Maria; Clapco, Steliana; Burcovschi, Ion; Tabacari, Ruslan; Domenco, Rodion
    Prezentul studiu s-a axat pe analiza influenței unor factori de mediu (temperatura și cantitatea de precipitații) asupra incidenței patogenilor florii-soarelui în diferite zone ale Republicii Moldova. Au fost analizate date privind infecția naturală a unui set de 7-15 hibrizi de floarea-soarelui cultivați în diferite zone pedoclimatice (Nord – Visoca, Soroca; Pelinia, Drochia; Centru – Băcioi, Chișinău; Sud – Grigorievca, Căușeni; Svetlâi, Comrat), în perioada 2015-2020, fiind relevată prevalența tulpinilor fungice în partea de nord și în cea de centru ale țării, caracterizate prin cele mai mari cantități de precipitații, și a angiospermei lupoaia – preferențial în partea de sud, cu indici de temperatură mai înalți.
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    INFLUENȚA CONDIȚIILOR AGROMETEOROLOGICE DIN ANUL 2020 ASUPRA CREȘTERII, DEZVOLTĂRII ȘI ROADEI DE FLOAREA-SOARELUI ÎN REPUBLICA MOLDOVA
    (CEP USM, 2021) Boian, Ilie; Domenco, Rodion
    În studiul de față, cu ajutorul programelor statistice moderne, a fost efectuată prelucrarea și analiza datelor factologice, ceea ce a făcut posibilă stabilirea variabilității temperaturii medii lunare a aerului și a cantității de precipitații în teritoriul Republicii Moldova pe parcursul perioadei de vegetație a anului 2020, cu elaborarea hărților respective pentru fiecare lună, fiind descrise condițiile agrometeorologice severe create pe parcursul procesului de creștere, dezvoltare și formare a roadei la floarea-soarelui. În scopul determinării intensității secetei din vara anului 2020 a fost calculat Coeficientul Hidrotermic Selianinov (CHT) pentru lunile iulie și august (fiind cele mai aride) pe tot teritoriul Republicii Moldova, stabilindu-se valoarea medie a coeficientului menționat pentru luna iulie de 0,5, iar pentru luna august – de 0,2, care corespund, respectiv, secetei puternice și foarte puternice. După suprafața afectată (cca 90% din teritoriul țării), seceta menționată mai sus, care a fost prezentă practic pe tot parcursul perioadei de vegetație a anului 2020, a fost una catastrofală. În rezultatul prelucrării datelor factologice cu privire la mărimea roadei de semințe la floarea-soarelui în anul 2020 pe teritoriul republicii, a fost posibilă elaborarea hărții privind variația roadei medii la 1 ha de floarea-soarelui în profil administrativ-teritorial. Efectuarea analizei comparative a roadei medii la 1 ha de floarea-soarelui din anul 2020 cu roada respectivă din anul 2019 și cu cea medie din premărgătorii 10 ani (2010-2019) a permis stabilirea impactului secetei puternice și foarte puternice din anul 2020 asupra roadei medii la 1 ha de floarea-soarelui în profil administrativ-teritorial. Astfel, am constatat că seceta din primăvara și vara anului 2020 a compromis cca 50% din roada de floarea-soarelui, constituind doar 11 q/ha față de 23 q/ha în anul 2019. Totodată, recolta medie pe țară la 1 ha de floarea-soarelui în anul 2020 a fost cu 6,7 q/ha mai mica față de roada medie din premăgătorii 10 ani (2010-2019), care a fost de 17,7 q/ha. Mai mică a fost doar roada medie la 1 ha de floarea-soarelui în anul 2012, fiind de 10 q/ha.
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    GENETICA REZISTENŢEI FLORII-SOARELUI LA LUPOAIE ( OROBANCHE CUMANA WALLR.)
    (Academia de Ştiinţe a Moldovei, 2020) Clapco, Steliana; Duca, Maria
    The angiosperm Orobanche cumana Wallr. (broomrape) is an obligatory root parasite, specific to sunflower crop. The main strategy to ensure the reduction of the negative impact of broomrape remains to be the development of resistant genotypes. This paper represents a synthetic analysis of the data related to sunflower genes for resistance to broomrape races, mapping of major genes and quantitative traits loci (QTL) with minor effects in resistance, as well as vertical and horizontal resistance mechanisms, in general, and the function of the genes involved in resistance, in particular. The study highlights the relevance of genetico-molecular, biochemical and physiological analyzes in this field and the importance of breeding programs focused on the development of sunflower genotypes incorporating multiple resistance genes in order to achieve the durable resistance.
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    IDENTIFICAREA GRADULUI DE REZISTENŢĂ LA LUPOAIE (RASA E) ÎN CADRUL UNOR GENOTIPURI DE FLOAREA-SOARELUI
    (CEP USM, 2008) Duca, Maria; Glijin, Aliona; Popescu, Victoria
    Molecular markers linked to broomrape resistance genes would permit a better understanding of genetic determinism of broomrape resistance in sunflower and f acilitate early selection by screening the presence of a few specific DNA markers. We have provided analysis of 29 sunflower lines with SCAR marker RTS05 linked to the sunflower Or5 locus conferring resistance to broomrape that belong to race E. Identification of 650 bp amplicon at 27 genotypes reveal the presence of Or5 gene, missing of this amplified product at Xenia ♀ and cytoplasmic male sterile genotype # 7 suggest the susceptibility to race E.
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    INFLUENŢA OROBANCHE CUMANA WALLR. DE DIVERSĂ ORIGINE ASUPRA CONŢINUTULUI DE ACIZI NUCLEICI LA FLOAREA-SOARELUI
    (CEP USM, 2007) Savca, Elena; Popescu, Victoria; Duca, Maria
    The purpose of this work was to estimate the influence of broomrape (Orobanche cumana Wallr.) with different origin (Moldova, Rostov, Volgagrad) on the content of NA (nucleic acids) in hybrids of the Valentino and Xenia varieties and in their parental lines. Significant decrease of NA content in leaves of the genotypes infected with broomrape from three geographical areas has been obtained. The degree of resistance of the studied genotypes by the total content of NA has been revealed: more resistant to broomrape was the Xenia variety, the population of local origin showed a greater tolerance in comparison with the populations from Rostov and Volgagrad.
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    EVALUAREA GRADULUI DE INFECŢIE LA UNELE GENOTIPURI DE FLOAREA-SOARELUI (Helianthus annuus L.) LA INTERACŢIUNEA GAZDĂ - PARAZIT (Orobanche cumana Wallr.)
    (CEP USM, 2007) Popescu, Victoria
    O. cumana is an important factor that significantly reduces the production of sunflower in the eastern part of the Mediterranean region. The main purpose of the present work is to reveal the infection ability of this parasite in some genotypes of sunflower cultivated in Moldova. It has been revealed that a population of broomrape, which had been received from Volgograd, had the most advanced capability for infection in comparison with populations from Rostov and Moldova. Genotypes of the Xenia variety have shown the greatest resistance in comparison withthe Valentino variety. The researchers have revealed the dependence of the infection ability from both genotype and the origin of parasites
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    ASPECTE ALE STATUTULUI OXIDOREDUCĂTOR LA DIFERITE GENOTIPURI DE FLOAREA-SOARELUI ATACATE DE LUPOAIE
    (CEP USM, 2007) Duca, Maria; Popescu, Victoria; Lupaşcu, Victor
    Accumulation of H2O2 and the activity of catalase in different genotypes of sunflower attacked by broomrape have been analyzed in this work. The accumulation of H2O2 in normal conditions is specified by genotype, being more active in the Xenia variety. The attack by broomrape leads to the intensification of the H2O2 synthesis in the analyzed genotypes, in particular in the Valentino variety. The activity of catalase decreases in attacked plants of the Xenia and Valentino varieties at the level of leaves as a result of the accumulation of SRO. The quantity of H2O2 correlates with the quantity of enzyme, both in normal conditions and in the plants attacked by broomrape.
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    ASPECTE PRIVIND ESTIMAREA GRADULUI DE STERILITATE A LINIILOR DE FLOAREA-SOARELUI
    (CEP USM, 2007) Duca, Maria; Port, Angela; Leviţchi, Alexei; Rotaru, Tudor
    Monitoring of the seed quality at different stages of plant breeding at sunflower represents a very important element in obtaining high yield hybrids based onCMS-Rfgenetic system. Sunflower represents a protandric plant with a single terminal inflorescence which contains 700-3000 individual hermaphrodite flowers, exposed on the calathidium, making manual emasculation almost impossible. That’s why the utilization of the male sterility was indispensable and necessary for the obtaining of the high level of hybridization at all the stages of sunflower breeding. Wide utilization of maternal lines, with cytoplasmic male sterility, and of paternal lines, with fertility restoring genes Rf, lead to the necessity to observe the stability and homogeneity of parental genotypes.Thus, for the paternal genotypes it is important to verify the presence and the stare of Rf genes, but maintaining male sterility is verified by the level of sterility control. Utilization of PCR-based methods with specific primers allows controlling genotype quality.
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    POSIBILITĂŢI DE ESTIMARE A PURITĂŢII GENETICE LA FLOAREA-SOARELUI
    (CEP USM, 2007) Duca, Maria; Leviţchi, Alexei; Rotaru, Tudor
    The efficiency of application of different techniques to monitor the biologic purity of initial material designed for the amelioration ensures the success of breeding programs. This means allow to estimate both, the homogeneity of inbred lines and the polymorphism of in frame of populations. Field tests are much easier and exact, but are time consuming, whereas laboratory tests provide fast results obtaining and reduce the expences for plant breeding programs. The utilization of different existant methods are determined by the budget, developed by the breeders, for the analyses and by the level of technical equipping of the laboratories. The most used method is based on the utilisation of storage protein electrophoretic spectra, being relative cheap and sufficiently exact.