OTIORRHYNCHUS LIGUSTICI L. (COLEPTERA: CURCULIONIDAE) II. METHOD FOR DETERMINATION OF THE DEGREE OF DAMAGE BY LARVA AND BIOCHIMICAL COMPOSITION OF THE ROOT SYSTEM IN DIFFERENT ALFALFA VARIETIES

DOI: 10.7904/2068 – 4738 – III(6) – 75

Ivelina NIKOLOVA, Nataliya GEORGIEVA, Anna ILIEVA

 Abstract: During the period 2006–2009 in the experimental field of IFC–Pleven were conducted studies with 8 varieties of alfalfa included in the Official variety catalog of Bulgaria (2005): Europe (France), Prista 2 (Obraztsov Chiflik, Ruse), Prista 3 (Obraztsov Chiflik, Ruse), Prista 4 (Obraztsov Chiflik, Ruse), Obnova 10 (IFC, Pleven), Pleven 6 (IFC, Pleven), Dara (IFC, Pleven) and Multifoliate (Obraztsov Chiflik, Ruse). For determination of the damage from the large alfalfa weevil Otiorrhynchus ligustici on the root system of plants was developed methodology depending on the root area and the damage area. The area of the roots was calculated by the formula S = (π * d * L) / 2, where π is 3.14; d–diameter of the root collar, L–length of the root. The area of the furrows оn the root system was product of length and width of the furrows. With the lowest percentage of furrows and tolerant to O. ligustici were Multifoliate, Prista 2 and Europe–respectively 10.38, 11.41 and 11.68%. Highly sensitive, with high percentage of damage were distinguished Dara, Prista 4 and Prista 3 (respectively 14.28, 14.05 and 13.58%). As a result of the caused damage the content of sugars and saponins increased as depending on the sensitivity of varieties the increase was different. In the tolerant varieties to the pest the increase in sugar content was less pronounced, but in the sensitive ones–stronger. In regard to the saponins the trend was reversed–the increase in the sensitive varieties was less and in the tolerant varieties–stronger which could be explained with the defensive reaction of plants to compensate the losses from damages of the pest.

Key words: alfalfa, varieties, method of damage degree, biochemical composition, Otiorrhynchus ligustici

OTIORRHYNCHUS LIGUSTICI L. (COLEOPTERA: CURCULIONIDAE) I. COMPARATIVE STUDY OF THE RESISTANCE OF ALFALFA VARIETIES

 DOI: 10.7904/2068 – 4738 – III(6) – 68

Ivelina NIKOLOVA, Nataliya GEORGIEVA

Abstract: From studies carried out during the period 2006–2009 in the experimental field of the IFC–Pleven with 8 alfalfa varieties included in the Official variety catalog of Bulgaria (2005): Europe (France), Prista 2 (Obraztsov Chiflik, Rouse), Prista 3 (Obraztsov Chiflik, Rouse), Prista 4 (Exemplary Chiflik, Rouse), Obnova 10 (EFC, Pleven), Pleven 6 (EFC, Pleven), Dara (EFC, Pleven) and Multifoliate (Obraztsov Chiflik, Rousse) it was found that in the year of the establishment of the stand there was partial damage from Otiorrhynchus ligustici. It was found that surface of caused damage was a major sign to determination ofthe degree ofinfestation from the insect pest as it increased from second tofourth yearon average from 5.6 to 42.1 cm2.Varieties of Multifoliate, Europe and Prista 2 were the least preferred and with low values of surface of damage, number and length of the gnawed furrows. These varieties can be used as sources of germplasm resistant to Otiorrhynchus ligustici.

Keywords: alfalfa, varieties, damage, Otiorrhynchus ligustici

 

DENSITY AND REDUCTION OF THE STAND AT ALFALFA VARIETIES (MEDICAGO SATIVA L.)

DOI:10.7904/2068 – 4738 – III(6) – 18

Natalia GEORGIEVA, Ivelina NIKOLOVA

 Abstract: With purpose to study the density and reduction of stand at 9 alfalfa varieties (Europe, Prista 2, Prista 3, Prista 4, Obnova 10, Pleven 6, Dara, Multifoliate and Dama)during 2006–2009 period in IFC–Pleven is carried out an experimental activity. The average density of stand at studied alfalfa varieties during the first year of development was 1313 plants/m2. The reduction during next three years was disproportionately and was the strongest pronounced during the second year–by 58.3% to the density of the stand in the previous year. During the third experimental year the reduction of alfalfa was still strong pronounced albeit with a lower value (51.1%) and during the fourth year it was 5 times less than that during the previous two years at average value of 10.6%. In the end of four–year experimental period the reduction at different varieties was in limits from 68.6% (Obnova10) to 85.7% (Dara) at average value for the species of 81.8%. It is established correlations with high negative value among the stand density and root mass weigh/plant (r=–0.811) and diameter of root collar (r=–0.692), and a correlation with medium negative value between the stand density and number of stems/plant (r=–0.488).

Key words: alfalfa, varieties, stands density, reduction

 

BIOCHEMICAL TRAITS AND CORRELATION ASSOCIATIONS BETWEEN CHEMICAL COMPOSITION AND SOME PARAMETERS YIELD IN BIRDSFOOT TREFOIL

Boryana  Georgieva CHURKOVA

Abstract:The field trial was conducted during the period 2002–2005 in the Experimental field of the IMSA Troyan for determination of the biochemical traits and correlation associations between chemical composition and some parameters yield in birdsfoot trefoil. There were included for study varieties Targovishte 1–St (Bulgaria) and 4 specimens of birdsfoot trefoil: local population (Hungary). K–30 (Serbia), Pulavskii (Poland) and Viking (USA). The studied accessions birdsfoot trefoil differed in chemical composition. The variety Viking (19.07%) was characterized with highest content of crude protein and lowest values of crude fibber (27.75%). Was positive correlation between the height of stems (r = 0.6229) and dry mass yield (r= 0.5271) and weak strength of correlation between the content of crude protein and the height stems (r = 0.4238). The registered quality traits a forage of birdsfoot trefoil formed under conditions of set on light grey pseudo podzolic are interest in the breeding.

Key words: birdsfoot trefoil, varieties, populations, chemical composition, correlation associations

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CHARACTERISTICS OF VARIETIES AND POPULATIONS BIRDSFOOT TREFOIL FOR SEED YIELD UNDER THE SOIL AND WEATHER GROWING CONDITIONS OF THE TROYAN REGION

Boriana CHURKOVA, Vladimir LINGORSKI

Abstract: During the period 2008–2010 in the experimental field of RIMSA Troyan on light gray pseudo podzolic soil were tested in the following varieties and populations birdsfoot trefoil; Shumen, Nesebar, Kiten, Tryavna, Sadovo, as well as genotypes of the varieties: V. Podolyanskii (Russia), Dedinovskii (Russia), Martanskii (Russia), Zora (Serbia), Bokor (Serbia), Smolenskii (Russia). The results from seed yield showed wide ranges of variation for the different years and on mean for the period: The tested varieties and populations were with high productive potential for the seeds yield. The differences in Number of pods/raceme, Number of racemes / plant, Number of seeds / pod, 1000–seed weight and conditioned also different values of formed seed yield of the tested varieties and populations. The seed yield average for the period of study in all tested cultivars and populations were superior the standard variety Targovishte 1.The highest seed yield was obtained from the Dedinovskii variety–0.260 t/ha, followed by Zora and Bokor–0.255 t/ha for a three year period. The higher seed yield of the tested birdsfoot trefoil varieties compared with the standard is due to the formation of the larger Number of pods/raceme, Number of racemes/plant, Number of seeds/ pod and 1000–seed weight. The correlation between seed yield and 1000–seed weight was very strong correlation (r=0.861786).

Key words: birdsfoot trefoil, varieties, populations, seed yield, structural elements, correlation associations

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