Insect assemblages and their preference for Lupinus albus and L. luteus

peer-reviewedWhile lupin has undergone extensive research to ascertain its suitability for growth as forage or grain legume crop, the present trend is for research to be centered on its applicability in the seed protein and oil industry. Study of the literature showed that no intensive study of the lupin insect fauna had been carried out in Bulgaria. The purpose of this study was to identify the insect assemblages associated with Lupinus albus and L. luteus, as well as the insect preference for them. Thrips sampling was made by the tapping-method, aphids were directly counted on the plants and the composition and population density of other species were recorded by sweepings. Insect fauna was studied for the first time in Bulgaria. The fauna was represented on L. albus by 64 species, belonging to eight orders, 28 families and 57 genera, including 23 beetles, 25 hemipteras, five thrips, three butterflies, three bees, one leaf aphid, two grasshoppers, one leafminer and one green lacewing. L. luteus had similar species composition but was less preferred by insects. The use of lupin cultivars with shorter and intense reproductive periods, with a lower content of crude protein and phosphorus, would give an environmentally friendly protection against insect pests, which would be suitable for an organic production system

Оценка на вредата, причинена от Bruchus pisorum L (Coleoptera: Chrysomelidae) върху някои показатели, свързани с качеството на семената при сортове фуражен грах (Pisum sativum L.)

It was evaluated the damage caused by Bruchus pisorum L (Coleoptera: Chrysomelidae) on the germination ability of pea farage varieties (Pisum sativum L.). Result of damage by Bruchus pisorum in seeds with parasitized larva was significant decrease of the germination by 16.4% percentage points, the length and weight of primary radicle by 16.8 and 24.5%, the length and weight of plumule by 12.3 and 14.1%, the vigor index of primary radicle and plumule by 32.5 and 32.8% as well as the germination index by 17.4%. The inhibitory effect was on average 17.8%. Essential significant changes in regard to the studied parameters were found for damaged seeds with bruchid emergence hole. In these seeds the gewrmination decrease by 58.3% percentage points, the length and weight of primary radicle by 34.1 and 36.2%, the length and weight of plumule by 31.8 and 34.3%, the vigor index of primary radicle and plumule by 81.1 and 82.1% as well as the germination index by 83.1%. The inhibitory effect was on average 58.3%. It was found that the damaged seeds with parasitoid emergence hole provided better possibility for growth and development of plants whereas the damaged seeds with bruchid emergence hole had significantly low germination, vigor and sowing characteristics. These seeds could not provide the establishment of well-garnished stand and stable yields. As tolerant to damage by Bruchus pisorum was distinguished Glyans variety for which the values of parameters related to germination and vigor of seeds were influenced in the lowest degree from the damage unlike the sensitive Pleven 4 variety. Dominant factor influencing germination ability of seeds for all analyzed parameters was the type of seeds compared to varietal appurtenance.През 2012г. опитното поле на Института по фуражни култури – Плевен е изведен опит с 5 сорта пролетен фуражен грах Глянс; Модус; Камертон и Свiт (украински сортове) и Плевен 4 (български сорт, стандарт). Направена е оценка на вредата, причинена от Bruchus pisorum L (Coleoptera: Chrysomelidae) върху кълняемата способност на сортовете грах (Pisum sativum L.). Резултат от вредата на B. pisorum при семена с паразитирана ларва е доказнано намаляване на кълняемостта средно с 16.4%тни единици, дължината и теглото на първичния корен с 16.8 и 24.5%, дължината и теглото на кълна с 12.3 и 14.1%, индекса на жизненост на първичния корен и кълн с 32.5 и 32.8%, както и индексът на кълняемост със 17.4%. Инхибиращият ефект е средно 17.8%. Съществени доказани промени по отношение на проучваните показатели се установяват при повредените с прозорче от имагинирал зърнояд семена, при които кълняемостта намалява с 58.3% тни единици, дължината и теглото на първичния корен с 34.1 и 36.2%, дължината и теглото на кълна с 31.8 и 34.3%, индекса на жизненост на първичния корен и кълн с 81.1 и 82.1%, както и индексът на кълняемост със 83.1%. Инхибиращият ефект е средно 58.3%. Установено е, че повредените с прозорче от имагинирал паразитоид семена осигуряват по-добра възможност за растеж и развитие на растенията, докато повредените с прозорче от имагинирал зърнояд семена са с доказана ниска кълняемост, жизненост и посевни качества. Тези семена не могат да осигурят създаването на добре гарниран посев и стабилни добиви. Като толерантен към повредите от B. pisorum се очертава сорт Глянс

Stem formation at alfalfa varieties and correlative dependences with some main parameters

During the period 2006-2009 in IFC-Pleven were studied 9 alfalfa varieties: Europe, Prista 2, Prista 3, Prista 4, Obnova 10, Pleven 6, Dara, Multifoliate and Dama. In the first year of its development alfalfa formed on average 1.42 number of stems per plant. During second and third year their quantity increased to 2.14 and 3.83 number whereafter during fourth year they decreased to 3.28. In all years (except the first year) was found a trend of increase in stem number from spring to autumn regrowth with average values 2.11, 2.85 and 3.05 respectively. Average for the four-year period the greatest number of stems (over the average for the nine studied varieties – 2.67) formed the Multifoliate variety followed by Europe, Prista 4, Obnova 10 and Dama. The varieties which are characterized by less density of stand (number of plants per unit area) had a greater number of stems per plant (r = -0.530). Correlations with mean and high positive value were found between stem formation and amount and distributions of rainfall during vegetation period (r = 0.989), year of alfalfa development (r = 0.861), nodulation (r = 0.763), weight of root mass (r = 0.411) as well as correlations with mean negative value between number of stems and percentage of damaged stems by Apion seniculus (r = -0.456)

EFFECT OF BOTANICAL INSECTICIDES NEEMAZAL-T/S AND PYRETHRUM APPLIED ALONE AND IN COMBINATION WITH DIFFERENT ORGANIC PRODUCTS ON THRIPS TABACI POPULATION DENSITY

The trial was conducted with spring forage pea (Pisum sativum L.) from 2011-2013 in the experimental field of the Institute of Forage Crops, Bulgaria. The effect of three insecticides was studied:  NeemAzal T/S®, Pyrethrum FS EC (botanical insecticides) and Nurelle D (synthetic insecticide) applied alone and in combination with the growth regulators Polyversum (biological growth regulator and fungicide) and Flordimex 420 (synthetic growth regulator); and an organic foliar fertilizer known as Biofa on Thrips tabaci population density. The treatment was conducted once (at budding stage) and twice (at budding and flowering stages). Between the studied biological insecticides against Thrips tabaci (Thysanoptera: Thripidae) Pyretrum FS EC was distinguished by its higher protective effect and fast initial activity, while NeemAzal-T/S exhibited slow initial activity and a relatively weak increasing after-effect. Combined use of the bioinsecticides with the organic foliar fertilizer Biofa and growth regulator Polyversum established synergism. The synergistic effect was more pronounced in combinations with Biofa. The highest efficacy among the organic products was found under combined use of Pyrethrum FS EC and Biofa whose protective effect approximated that of Nurele D Chlorsyrine 550 EC. The double treatment of plants (at budding and flowering stages) with Pyrethrum and NeemAzal reduced the density of thrips by 28.9% and 20.1% respectively compared to the single application, without consideration of the method of use. The most efficient combination among organic products was the use of Pyrethrum with Biofa where the density of thrips decreased by 53.7%, followed by Pyrethrum with Polyversum (by 44.0%) and NeemAzal with Biofa (by 39.5%) irrespective of the stage of treatment

Efficacy of organic products against insect pests in alfalfa grown for seeds

Organic pesticides can be excellent alternatives to chemical pesticides. They occupy an important place in the plant protection sector. Evaluation of the efficacy was conducted using an alginate from seaweed (organic insecticide) and two organic fertilizers (highly concentrated complex organic fertilizer and natural CO2 fertilizer), used alone and in combinations to control major pests in alfalfa seed production such as alfalfa seed chalcid Bruchophagus roddi Guss., alfalfa plant bug, Adelphocoris lineolatus Goeze and pea aphid, Acyrthosiphon pisum Harr. We conducted field trials during three growing seasons. Treatments were carried out at the beginning of the flowering stage in second regrowth. The seaweed alginate had high efficacy and excellent control on the three insect species density one week after treatment (over 80%), while the complex organic fertilizer exhibited insecticidal action against pests and its effect exceeded 60% seventy days after treatment and provided a medium level of control. The mix of the two organic products provided the highest efficacy and long-lasting effects on the three insect species and additive effects were observed. The combination realized the highest seed yield and an increase of 29.7%. Treatment with organic products is suitable for organic farming

Platinum (II) Compounds With Antitumor Activity Studied by Molecular Mechanics

A series of Pt(ll) complexes with antitumor properties: [1,2-bis(2,6-dichloro-4-hydroxyphenyl)ethylenediamine]PtL2 (meso-1-PtL2) and [erythro-1-(2,6-dichloro-4-hydroxyphenyl)-2-(2-halo-4-hydroxyphenyl)ethylenediamine]PtL2, [2L=2Cl−,2I−,SO42−; halo = F (erythro-8-PtL2),halo = Cl (erythro-9-PtL2)] has been modelled by molecular mechanics (MM). The MM calculations were carried out for different isomers and ligand conformations meso-δ, meso-λ, d,l-δ, d,I-λ. The compounds with the lowest MM energies have the same geometries as those obtained by X-ray analysis. The calculated MMX energy orders: meso-1-PtL2 < erythro-9-PtL2 < erythro-8-PtL2 for L=I−, Cl− and SO42− are reverse to the known antitumor activity order - the lowest energy complex (the most stable one)is the one with the highest estrogen activity (meso-1-PtL2). The type of the leaving group (L) does not alter the energy order, which is in agreement with the biological experiments that show a slight dependence of the estrogen properties on the leaving group type

Variation in allelopathic tolerance of vetch cultivars to Sorghum halepense L. (Pers.) extracts

Using allelopathic tolerance of crops and cultivars is considered a promising supplement to weed control strategies. In order to evaluate the allelopathic tolerance of vetch cultivars to Sorghum halepense extracts in germination and initial growth of the crop, a multi-factorial lab experiment was carried out based on a completely randomized design with four replications. The experimental factors were nine vetch cultivars ('Liya', 'Lorina', 'Moldovskaya', 'Obrazets 666', 'Asko', 'Violeta', 'Viola', 'Beta WP', and 'Panonskaya'), two aqueous extracts (of shoot and root biomass of S. halepense) and four concentrations of the extracts (1.0%, 5.0%, 10.0% and distilled water as a control). An analysis of variance showed a significant influence of the studied factors. The results revealed variation in responses of the nine cultivars to the allelopathic effect of S. halepense. The extracts applied at different concentrations had a significant inhibitory effect on seed germination (from 2.8 to 27.3% for different cultivars), germ length (from 4.6 to 48.7%) and germ weight (from 3.6 to 34.0%). The lowest concentration (1.0%) also had a stimulating effect on growth parameters, most pronouncedly in two cultivars ('Beta WP' and 'Viola'). Total effects of the weed extracts on seed germination and initial development selected 'Beta WP', 'Violeta' and 'Obrazets 666' as the most tolerant cultivars, as opposed to 'Liya' and 'Panonskaya', which were more sensitive. The cultivars with seeds that have greater biomass per 1000 seeds, higher seedling vigour index and protein content were found to be less sensitive to the suppressing effect of S. halepense extracts. These cultivars can be successfully used in organic fields with high density of S. halepense or in a conventional production system with a reduced use of herbicides

Optimization of Neutral Comet Assay for studying DNA double-strand breaks in pea and wheat

This study describes an adaptation of the Comet assay under neutral conditions for mono- and dicotyledonous plants pea (Pisum sativum L.) and wheat (Triticum aestivum L.). Modifications concern lysis and electrophoresis steps, respectively. Electrophoresis was carried out varying the intensity of the electric field. A linear relationship between the percentages of DNA in the tail from control background with alteration of intensity was found. Trypan blue dye exclusion test was used in order to determine the intactness of nuclear membrane of the isolated nuclei from both plant model systems. Assessment was conducted on non-irradiated and irradiated nuclei on a monolayer with three doses of UVC. It was found that the share of intact nuclei (trypan blue negative ones) is about 95% in controls. Gradual dose-related increase of damaged nuclei was observed in both species, reaching statistical significance only at the higher dose applied

Is the C=O frequency shift a reliable indicator of coumarin binding to metal ions through the carbonyl oxygen?

The coumarin ligand, 4-hydroxy-3-nitro-2H-chromen-2-one (Hhnc) and its Cu(II) and Ag(I) complexes were studied by DFT calculations at B3LYP/B1 and PW91/B1 levels. MEP of the deprotonated ligand, hnc-, and energy calculations of model metal complexes predicted the ligand binding to the metal ion through the hydroxyl and the nitro oxygens in agreement with experiment. Based on precisely selected Cu/Ag model complexes with hnc-, a relation between the vibrational behaviour of the ligand donor groups and the ligand binding modes in the complexes was deduced. The observed carbonyl m(C=O) downshift (50–90 cm-1) is attributed to intermolecular H-bonding formed between the C@O group and lattice water molecules or due to the C@O binding to the metal ion in case of bridging coumarin ligand (in Aghnc). Much larger m(C=O) downshift (~220–240 cm-1) is predicted in case of monodentate or bidentate (with the nitro group) bonding of the carbonyl C=O group to the metal ion

Nutritive value responses to biological products in alfalfa forage (Medicago sativa L.)

The effects of the biological insecticides Madex and Agricolle, applied alone or in combination with the biological fertilizers Lithovit and Nagro, on chemical composition and enzyme in vitro digestibility, as well as energy feeding value of alfalfa dry mass were studied. Treatments were carried out at the beginning of the flowering stage during the second cutting for control of economically important pests, testing a method of organic pest control. Independent and combined applications of several biological products were found to influence positively the chemical composition, enzyme in vitro digestibility, and energy and protein nutritional value of alfalfa feed. An optimal combination of decrease in the content of plant cell wall fiber components and a significant increase in forage enzyme in vitro digestibility was revealed after the application of Agricolle and a combination of Agricolle and Nagro. Digestibility reached 60.4 and 59.9%, respectively, which is an increase of 12.0 and 11.0%. Alfalfa low fiber, high protein content, and digestibility made a very good complement to grains and other forages in dairy rations after treatment with biological products