Tag Archives: damage

393–403 D. Derevjanko, I. Holovach, V. Bulgakov, V. Kuvachev and, J. Olt
Theoretical and experimental research into impact of threshing tools in combine grain harvesters on quality of cereal crop seeds
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Theoretical and experimental research into impact of threshing tools in combine grain harvesters on quality of cereal crop seeds

D. Derevjanko¹, I. Holovach², V. Bulgakov², V. Kuvachev³ and, J. Olt⁴*

¹Zhytomyr National Agroecological University, 7, Staryi Blvd, UA 10008 Zhytomyr, Ukraine
²National University of Life and Environmental Sciences of Ukraine, 15, Heroyiv Oborony street, UA 03041 Kyiv, Ukraine
³Dmytro Motornyi Tavria State Agrotechnological University, 18B, Khmelnytsky Ave, UA 72310 Melitopol, Zaporozhye Region, Ukraine
⁴Estonian University of Life Sciences, Institute of Technology, Kreutzwaldi 56, EE 51006 Tartu, , Estonia
*Correspondence: jyri.olt@emu.ee

Abstract:

The theoretical and experimental research into the micro-damaging of cereal crop seeds in the process of their harvesting by combine grain harvesters in relation to the strains, forces and stresses imparted to them by the threshing tools has been carried out. The propagation of deformations and cracks in the seeds as well as the nature of their strength and the damage that is sustained, when the critical load is applied, have been investigated. It has been established that the onset of cracks, the direction of their propagation and their quantity in the bodies of grain seeds depends in the majority of cases on the direction of action of the external forces and the specifics of the seeds’ internal biological properties. It has been established that the strength of the grain seed is, apart from the arisen cracks, also under the significant effect of the microtraumas in the germ, endosperm as well as the seed coat and shell. Theoretical calculations have been carried out on the PC and the effect that the drum and rotor threshing apparatus have on the deformation and damage sustained by cereal crop seeds has been substantiated. The said calculations and the obtained graphic relations support the results of the experimental investigations and prove that the macro- and especially micro-damage sustained by the seeds of winter wheat and rye is different, when they are threshed with the use of different types of threshing apparatus, which has a considerable impact on the final quality of the harvested cereal crop seeds. The results obtained in the experimental investigations, field and laboratory tests on the topic of the effect of mechanical loading on the sustained damage and quality of seeds indicate that the damage rate accounted for the work processes of the reaping and postharvest treatment of the cereal crop heaps of different winter wheat varieties with the use of rotor threshing apparatus is 3.1% as compared to the drum threshing apparatus – 6.4%, that is, 2 times lower. The total amount of the seeds with microtraumas collected in the hopper after threshing amounts to 23.0% and 54.0%, respectively, which is a significant difference. Similar results have been obtained in the experimental investigations on the effect of the equipment on the sustained damage and quality of seeds in the cleaning, chemical treatment and sowing of cereal crops.

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55–62 R. Sestras, E. Tamas and A. Sestras
Morphological and genetic peculiarities of fruits in several winter apple varieties which confer resistance to damage
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Morphological and genetic peculiarities of fruits in several winter apple varieties which confer resistance to damage

R. Sestras¹, E. Tamas¹ and A. Sestras²

¹University of Agricultural Sciences and Veterinary Medicine, Faculty of Horticulture, No. 3-5 Manastur St., 3400 Cluj-Napoca, Romania; e-mail: rsestras@email.ro
²Horticultural Research Station, 3-5 Horticultorilor St., Cluj-Napoca, Romania

Abstract:

Among 15 winter apple varieties studied for their resistance to the damage of fruits, Golden Delicious was susceptible to fruit injury, while the Florina, Idared and Granny Smith can be considered resistant to pricking, cutting and hitting of the fruits. The variability of the morphological characteristics of the fruits was relatively low, the fruit volume being averagely variable and the fruit resistance to injury being the character with the highest variability (s% = 26.4). The resistance of the fruits to injury was not correlated with their height, diameter, weight, shape and volume. The characteristics of the fruits have a strong genetic determinism, but the additive effects of the genes do not play the most important role in all cases. For the fruit resistance to injury the big differences between heritability coefficients values in a broad and narrow sense signify the fact that the resistance to injury of apples is influenced not only by additive effects but also by the dominance and epistasis effects of the genes.

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123–130 K. Hiiesaar, L. Metspalu, P. Lääniste and K. Jõgar
Specific composition of flea beetles (Phyllotreta spp ), the dynamics of their number on the summer rape (Brassica napus L. var. oleifera subvar. annua) Mascot
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Specific composition of flea beetles (Phyllotreta spp ), the dynamics of their number on the summer rape (Brassica napus L. var. oleifera subvar. annua) Mascot

K. Hiiesaar¹, L. Metspalu¹, P. Lääniste² and K. Jõgar¹

¹Institute of Plant Protection, Estonian Agricultural University, Kreutzwaldi 64, 51014, Tartu, Estonia; e-mail: hkelli@eau.ee
²Institute of Field Crop Husbandry, Estonian Agricultural University, Kreutzwaldi 64, 51014, Tartu, Estonia

Abstract:

The specific composition of the flea beetle Phyllotreta spp (Coleoptera: Chrysomelidae), time of its appearance and dynamics of its number on the summer rape cultivar Mascot were determined. During the observation period, 6 species of flea beetles were found: Phyllotretaundulata  Kutsch., Ph. nemorum L.,  Ph. vittata  (Ph. striolata), Ph. nigripes F. Ph. atra and Ph. vittula. First flea beetles appeared at the time of the sprouting of rape plants. In the course of the entire observation period, the most numerous of these was the small striped flea beetle Ph. undulata. Proportion of the other species not often exceeded 10%. Very warm and dry weather following the sprouting of plants caused a rapid increase in the number of the pests and the maximum number was reached in a short time. A somewhat larger number of beetles was found on the edge plots. The field was sprayed three times, using Fastac (alphacypermethrin). Although after the first spraying the number of pests had decreased to almost zero, one week later the number of beetles began to rise again. Ten days after the spraying, the number of pests in the control and the sprayed variant had become equal, 2.0 and 2.2 individuals per plant. The second spraying lowered the number of pests again  down to zero. At that time the plants were reaching the stage of  3-4 true leaves, the time when the growth rate is the fastest. The third spraying was primarily directed against pests damaging generative organs: pollen beetles and weevils, and at that time plants began to form secondary racemes, and primary racemes lengthened. For controlling of flea beetles spraying was no more necessary.

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17–29 K. Hiiesaar, L. Metspalu, P. Lääniste, K. Jõgar, A. Kuusik and J. Jõudu
Insect pests on winter oilseed rape studied by different catching methods
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Insect pests on winter oilseed rape studied by different catching methods

K. Hiiesaar¹, L. Metspalu¹, P. Lääniste², K. Jõgar¹, A. Kuusik¹ and J. Jõudu²

¹Department of Plant Protection, Estonian Agricultural University, Kreutzwaldi 64, 51014 Tartu, Estonia; e-mail: hkelly@eau.ee
²Department of Field Crop Husbandry, Estonian Agricultural University, Kreutzwaldi 64, 51014 Tartu, Estonia

Abstract:

The distribution, species association and number of pest insects on winter oilseed rape of varieties ‘Wotan’ and ‘Express’ were studied in field experiments. Three catching methods were used: black plastic basins on the soil surface between plants, yellow flight traps filled with water at the height of the crop canopy and the shaking of plants above a plastic basin. The most abundant pest species was the pollen beetle,Meligethes aeneus, while the number of individuals from the species M. virescens in traps was much lesser. The other  important group of pest insects were weevils Ceutorrhynchus spp., the most common of which was the cabbage seed weevil, C. assimilis.  Three species of flea beetlesPhyllotreta undulata, Ph. vittata and Ph. nemorum were typical contents of traps during May. In the last decade  of May, there was a large number of thrips (Thysanoptera, Tripidae) in traps.
Winter oilseed rape began to flower to some extent later, when pest insects of cruciferous plants had ended their hibernation. Therefore, the pests first inhabited weeds and already flowering plants, from where they later moved onto winter oilseed rape.
    In the field of winter oil seed rape, chemical pest control with a pyrethroid, Fastac, did not significantly influence the abundance of  pest insects. In the last decade of May, the total number of beetles in all test variants was relatively small, but, at the beginning of June, it increased almost to an equal extent. On the basis of flight traps, heavy damage of pods could be assumed, however, only a few larvae fell into traps on the soil surface, and virtually no damaged pods were detected. Thus the spraying with Fastac had no significant effects on the number of insects caught in traps.

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