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Breeding research for the common wheat crop has focused on quality and yield. These are closely related to each other because high yield without adequate quality or good quality without satisfactory production are not profitable for the farmer. At A.R.D.S. Secuieni, in the period 2019-2022, Romanian winter wheat varieties were tested in order to establish their yield and quality. These were influenced by the variety, the climatic conditions but also by the phase fertilization applied. On average in the three years studied, the productions had values between 7108 kg/ha (Pitar) and 8442 kg/ha (Semnal) in the case of fertilized variants and between 6201 kg/ha (Miranda) and 7669 kg/ha (Abundent) in the case of unfertilized variants. Regarding the quality of common wheat varieties, the content in protein, starch and gluten was monitored. [ABSTRACT FROM AUTHOR]

The species Diabrotica virgifera virgifera Le Conte (western corn rootworm) belongs to the order Coleoptera, family Chrysomelidae. It originates from North America and entered in Europe in 1992, in Yugoslavia. It entered in Romania in 1996, when three specimens were recorded in Nădlac (Arad county), and since then the range of the pest has continuously expanded (Manole, 2017). To reduce the spread of this pest, it is recommended to avoid monoculture and practice rotation. It can reduce the root attack to a minimum level, the larvae not being able to survive in soils cultivated with other plants (Ciobanu, 2009). The most common strategies used to protect maize roots against the pest Diabrotica virgifera virgifera are the application of an insecticide to the soil at seeding and the use of an insecticide in the seed treatment (Sutter et al., 1990). The average number of larvae per plant varied from 1 to 5, the fewest larvae being recorded in the variant where the granular insecticide Force G was applied to the soil at a dose of 15 kg/ha. The frequency of swan neck ranged from 0% to 58%. The attack produced by adults on the leaf recorded frequencies between 32% and 66%, and on maize silk, the attack was 100%. The average number of adults per plant was between 9 and 10. [ABSTRACT FROM AUTHOR]

The species Diabrotica virgifera virgifera Le Conte (western corn rootworm) is part of the order Coleoptera, family Chrysomelidae and is an invasive alien species native to Central or South America. In Europe, it was reported in 1992, and in Romania in 1995. The attack produced by the species Diabrotica virgifera virgifera significantly reduces maize production, the pest being a carrier of various pathogens that cause crop plant diseases (Bacal et al, 2020). In the present paper, are presented partial results regarding the appearance, evolution and flight of adults of the species Diabrotica virgifera virgifera, respectively, the attack that the insect produces in the maize crops in the Central area of Moldova. In the year 2021, the flight of this species began in the first decade of July and continued until the third decade of September. The maximum flight peak was achieved in the third decade of July, being 180 specimens/trap. In the year 2022, the flight of the species started in the first decade of July and continued until the end of September. The maximum flight peak was recorded in the first decade of August, when a number of 182 specimens/trap were collected. In the year 2022, a maize silk attack frequency of between 85% and 100% was recorded. From the results obtained in 2022, the treatment carried out on the vegetation with insecticides reduced the number of adults per plant from 1.6 specimens to 0.1 specimens. [ABSTRACT FROM AUTHOR]

Maize is cultivated on 2,678.5 thousand ha in Romania, and its cultivation on large areas attracts a number of pests that attack various parts of the plant in different developmental phases. One of these dangerous pests is Ostrinia nubilalis Hbn., a species that occurs during the growing season of maize and causes production losses by the attack on the stem and cob. The larvae produce various attacks, influenced by climatic conditions, the frequency of attacked plants being between 15.7 and 67.9% in the south-west of the country, in the south-east of the country varies between 43.3-79.4%, in the Transylvanian Plain has values between 60.00% and 81.88%, in the west of the country the attack is around 41%, and in the east of the country by 30.20%. The importance of attacks by Ostrinia nubilalis Hbn. at maize led to the initiation of studies in 2019 at the A.R.D.S. Secuieni to determine the influence of technological factors on the parameters of attack (frequency of attack, average number of holes, galleries and larvae and average length of gallery) produced by larvae. For the maize sown in epochs, the optimal epoch, the IIIrd, recorded the lowest values of the parameters: the frequency of the attack was 18.65%, were identified 0.60 holes/plant, 0.39 galleries/plant and 0.38 larvae/plant, and the average length of the galleries was 8.39 cm. The behavior of genotypes at the attack produced by larvae varied within very wide limits, the frequency of the attack was between 36.56% at the early genotype Vibrion and reached 48.50% at the late genotype Olt. [ABSTRACT FROM AUTHOR]

From the first report of the species Ostrinia nubilalis Hbn. in Romania in 1898, the insect spread and is currently present in all corn crops in our country. The production losses that the insect produces vary from one year to another, from one field to another, one of the factors influencing the reduction of the attack is the cultivated maize hybrid. This paper presents the preliminary results obtained in 2019, where was studied the influence of the precocity group and the hybrid variety on the attack level produced by the european corn borers larvae in the conditions of the Center of Moldova. The studied maize hybrids show different values of the attack produced by the Ostrinia nubilalis Hbn. larvae. Depending on the maturity group, the genotypes that recorded high attack values are those from FAO groups 400 - 430 (Kerala and Olt), followed by semi-early hybrids in FAO groups 370-380, and the lowest attack was recorded by the hybrid Vibrion maize classified as FAO maturity group 290. Of the three maize varieties tested, the sweet hybrid was the most affected by the european corn borer larvae attack followed by the dentate ones from the semi-early maturity groups and the flint variety (Vibrion) was not affected due to the short period of vegetation. [ABSTRACT FROM AUTHOR]

In addition to the 25 species of harmful insects, of economic importance for the maize crops identified in Romania, of which, the corn leaf weevil (Tanymecus dilaticollis) and wireworms (Agriotes spp.) are very dangerous soil pests, it is added species Diabrotica virgifera virgifera Le Conte. The species was identified in Europe in 1992, and in 1996 it spread to Romania. The spreding area of the pest was initially restricted in the south-west and west, in the counties of Arad, Timiș, Caraș-Severin, Mehedinți, Dolj, Hunedoara, then gradually spread to all areas of maize cultivation. In the eastern part of the country, respectively in thearea of influence of the A.R.D.S. Secuieni (Neamț, Bacău and North Vrancea counties area) the insect was reported in 2015, the flight intensity, abundance and frequency of attack increased from year to year, which imposed as a necessity the monitoring of the species and the way of attack. The species Diabrotica virgifera virgifera Le Conte causes damage to maize crops both in the larval stage and in the adult stage. Oligophagous larvae feed on the roots of several species of grasses, except sorghum, which they gnaw, cut off, the strongly attacked plants have the slanted stem in the form of a swan's neck, the plants dry prematurely, production losses being 10 - 13%, sometimes higher, up to 55%. Adults are polyphagous, but especially feed on the leaves, silk and corn pollen, but also on the grains at the top of the cobs. The attack reported on the corn leaves is similar to that of the species Lema menalopa. Observations and determinations on the appearance and flight of adults were made using yellow glue traps, which have been installed in maize crops since the beginnig of June. The first adults were registered in the first decade of July, the flight continued without interruption until the end of September. During this period July - September, the adults made a single flight curve, the maximum flight peak was recorded in the second decade of August and totaled an average of 470 specimens / trap / decade. Knowing the abundance of Diabrotica virgifera virgifera Le Conte in agricultural crops in Central Moldova, it is necessary to continue the research on knowledge of bioecology, factors influencing the emergence, evolution and attack, measures to prevent and control the pest. [ABSTRACT FROM AUTHOR]