Study of Introduced Varieties of Perennial Grass Species Grown in the Conditions of Central Northern Bulgaria

Abstract

Abstract. Perennial grass species have many valuable qualities that can be used in solving the problem of producing more feed for livestock. In this regard, four introduced varieties of perennial grasses (Phleum pratense L., Agrostis alba L., Dactylis glomerata L. and Lolium perenne L.) were studied in the conditions of Central Northern Bulgaria. The total amount of green biomass (2011-2013 periods) ranged from 394.93 to 786.13 g m -2 as the arrangement was in the following ascending order: perennial ryegrass, white bentgrass, common timothy and cocksfoot. The digestibility of forage dry matter was from 52.54 to 56.93%. Potential energy feeding value was the highest in cocksfoot and protein feeding value was the highest in ryegrass. Evaluating rank of the general parameters for composition, enzyme digestibility and their arithmetical sum showed that rank 1 belonged to L. perenne, cv. Svyatoshynskiy and rank 2 was obtained for D. glomerata, cv. Horlytsya, followed by P. pratense, cv. Pidhiryanka and A. alba, cv. Halychanka.

Genetic basis of growth, spring phenology, and susceptibility to biotic stressors in maritime pine

“…It can remain in an endophytic form, that is, without causing any symptoms, until stressful environmental conditions, such as drought (Desprez-Loustau et al, 2006;Stanosz et al, 2002), hail storms (Zwolinski et al, 1990), or changes in the nitrogen concentration of the soil (Piou et al, 1991;Stanosz et al, 2004), weaken the host and trigger D. sapinea pathogenicity. Trees from all ages are affected (Chou, 1978;Georgieva & Hlebarska, 2017), though seedlings and old trees show increased susceptibility (Swart & Wingfield, 1991). The fungus can be found in many conifers, especially in the genus Pinus.…”

Yield Response and Competition Ability of Italian Ryegrass, Red Clover and Their Mixture to Different Technological Conditions�

“…Therefore DM production between 11 t/ha (Tp_25_N0) and 17 t/ha (Tp_12,5_N100) were recorded in this plots, values much higher than those harvested from the experimental plots sown with Italian ryegrass. There are many other researchers which pointed out the potential of red clover sown either pure or in mixture with a suitable perennial grass, to maintain high output of quality herbage without the aid of fertilizer N (McBratney, 1984; Queen et al, 2009;Georgieva et al, 2015;Kosev, 2015). There are several researchers which highlighted that perennial forage grasses have many valuable qualities, which can be used in obtaining of more Note: Tp_12,5_N0 -red clover, unfertilized, sown on 12.5 cm; Tp_12,5_N50 -red clover fertilized with N50P60K80, sown on 12.5 cm; Tp_12,5_N100 -red clover fertilized with N100P60K80, sown on 12.5 cm; Tp_25_N0 -red clover, unfertilized, sown on 25 cm; Tp_25_N50 -red clover, fertilized with N50P60K80, sown on 25 cm; Tp_25_N100 -red clover, fertilized with N100P60K80, sown on 25 cm; Lm_12,5_N0 -Italian ryegrass, unfertilized, sown on 12.5 cm; Lm_12,5_N50 -Italian ryegrass, fertilized with N50P60K80, sown on 12.5 cm; Lm_12,5_N100 -Italian ryegrass, fertilized with N100P60K80, sown on 12.5 cm; Lm_25_N0 -Italian ryegrass, unfertilized, sown on 25 cm; Lm_25_N50 -Italian ryegrass, fertilized with N50P60K80, sown on 25 cm; Lm_25_N100 -Italian ryegrass, fertilized with N100P60K80, sown on 25 cm; Mix_12,5_N0 -mixture, unfertilized, sown on 12.5 cm; Mix_12,5_N50 -mixture fertilized with N50P60K80, sown on 12.5 cm; Mix_12,5_N100 -mixture fertilized with N100P60K80, sown on 12.5 cm; Mix_25_N0 -mixture, unfertilized, sown on 25 cm; Mix_25_N50 -mixture, fertilized with N50P60K80, sown on 25 cm; Mix_25_N100 -mixture, fertilized with N100P60K80, sown on 25 cm.…”

On the Behavior of Certain Artificial Grasslands on the Slopes of the Central Balkan Mountain in Bulgaria

“…The nature of the study will determine the type of cooperation required (Romeo, 2000).Besides laboratory, pot, and field experiments were also conducted with cultivars and populations of meadow grasses created by the author (Mitev, 1997;2000, etc.). There is a tendency to develop cultivars with increased allelopathic potential that will allow them to successfully cope with local habitat conditions (Georgieva et al 2015).The idea arises to find another approach in this direction. The studies have shown that the increased allelopathic potential leads to overexpenditure of resources and, accordingly, lowers the productivity of grasslands (Mitev and Belperchinov, 1996;Mitev and Yasheva, 1998).It is possible to create more productive and sustainably developing meadow associations based on the existing potential.…”