Esvet Acikgoz

Production of sweet sorghum (Sorghum bicolor L. Moench) increases with increased plant densities and nitrogen fertilizer levels

Abstract The main aim of this study was to evaluate the effects of different intra-row spacings and nitrogen levels on forage, dry matter, seed yield and some other yield components of sweet sorghum (Sorghum bicolor L. Moench). Five intra-row spacings (5, 10, 15, 20 and 25 cm) and five N fertilization rates (0, 50, 100, 150 and 200 kg ha−1) were tested under irrigated conditions in Bursa, Turkey in 2002 and 2003 growing seasons. Yields decreased with increasing intra-row spacing, and increased up to 100 kg N ha−1. Five- or 10 cm intra-row spacings and 100 kg N ha−1 fertilization gave more than 80 tonnes (t) ha−1 forage or 30 t ha−1 dry matter yield based on pooled data of both years. The two-year average seed yield ranged from 3.15 to 4.53 t ha−1, with the highest yield being obtained from the combination of 10–20 cm intra-row spacing and 150 kg N ha−1. Five- or 10-cm intra-row spacings, and 100 or 150 kg ha−1 N fertilization regimes are suggested to maximize forage, dry matter and seed yield in sweet sorghum under similar soil and climatic conditions.

Annual Forage Legumes in the Arid and Semi-Arid Regions of Turkey

The cultivation of forage legumes, particularly vetches, is described with reference to the conditions of cultivation in Turkey. The uses of vetches are outlined and the problems of cultivation highlighted. Experiments to improve legume yields and those of subsequent cereal crops are also discussed.

Year-round nitrogen fertilization effects on growth and quality of sports Turf mixtures

Abstract The effect of three different nitrogen (N) levels applied monthly year-round on the growth and quality aspects of four different sports turf mixtures consisting of perennial ryegrass (Lolium perenne L.), tall fescue (Festuca arundinacea Schreb.), Kentucky bluegrass (Poa pratensis L.), creeping red fescue (Festuca rubra var. rubra L.), Chewings fescue (Festuca rubra var. commutata Gaud.), slender red fescue (Festuca rubra var. trichophlla), and Colonial bentgrass (Agrostis tenuis L.) were evaluated in this three year field irrigated study. Nitrogen was applied monthly at rates of low (2.5 g N m− 2), medium (5.0 g N m− 2), and high (7.5 g N m− 2) starting in the first month after the sowing date in November 1998 and continuing for 34 months. The seasonal average differences in color, quality, cover percentages, and clipping yields of the mixtures were not significant. In contrast, N treatments greatly affected these characteristics, and differences were statistically significant at all the individual sampling dates and for seasonal averages during the three years of this study. Turf color and quality were generally associated with the N fertility treatments. Increasing N significantly (P < 0.01) enhanced the color and quality ratings and increased clipping yields in all turf mixtures. Fall and winter fertilizations significantly (P < 0.01) improved color and quality of turf without winter damage in the experimental area with mild winters. In particular, the high (7.5 g N m− 2) rate resulted in decreased rooting at the both 0–15 cm and 15–30 cm depths.

EFFECTS OF NITROGEN APPLICATION TIMING ON GROWTH AND QUALITY OF A TURFGRASS MIXTURE

A 3-year field study was conducted to determine the influence of nitrogen (N) application timing on the growth and quality of a turfgrass mixture consisting of perennial ryegrass (Lolium perenne L.), Kentucky bluegrass (Poa pratensis L.), creeping red fescue (Festuca rubra var. rubra L.), and chewings fescue (Festuca rubra var. commutata Gaud.) under irrigated conditions. Nitrogen was applied annually at the rate of 30 g m−2 year−1, with six application regimes: control (no N), single spring (30 g m−2), single fall (30 g m−2), spring + fall (15 + 15 g m−2), spring + summer + fall (10 + 10 + 10 g m−2), and monthly from April through September (5 g m−2). Color, turf quality, clipping weights, and shoot density were correlated with fertilizer rates and application timing in this study. Fertilization monthly or every 2 months resulted in more uniform color and turf quality and less clipping weights than with comparable heavy spring and fall fertilizations. Heavy N applications in the fall did not cause winter injury and produced significantly darker color and more uniform appearance in early spring than other N applications. All N-fertilization regimes increased shoot density, but spring fertilization stimulated density the most. Nitrogen applied monthly or every 2 months was enough to enhance the color, turf quality, and shoot density of the turf during the growing season but did not greatly affect the growth rate.

Common Vetch ( Vicia sativa L.) Germplasm: Correlations of Crude Protein and Mineral Content to Seed Traits

In order to increase knowledge of seed nutritive value and to demonstrate its relationship in common vetch (Vicia sativa L.) germplasm, 388 common vetch accessions were grown under field conditions in 2008–2009 growing season in Bursa province of Turkey. Seeds were analyzed for seed minerals (Ca, Cu, Mg, Mn, P, S, Zn and K) and crude protein (CP) content. The accessions were grouped according to testa and cotyledon color and seed size, and the results were evaluated by analysis of variance to determine relationships between minerals and CP content, testa and cotyledon colors, and seed weight. In general, there was no significant difference between testa colors or cotyledon colors in minerals and CP content. However, seed weight was closely associated with minerals and CP contents in this study. Analysis of variance and correlation analysis showed that seed weight was closely associated with some minerals and CP content. The small seeds had significantly higher Ca, Cu, Mg, Mn, S, Zn and CP contents than medium and large seeds.

Pathogenicity, reproduction and foraging behaviours of some entomopathogenic nematodes on a new turf pest, Dorcadion pseudopreissi (Coleoptera: Cerambycidae)

Abstract Entomopathogenic nematodes (EPNs) in the families Heterorhabditidae and Steinernematidae have considerable potential as biological control agents of soil-inhabiting insect pests. In the present study, the control potential of the EPNs Steinernema carpocapsae (TUR-S4), S. feltiae (Nemaplus), S. carpocapsae (Nemastar), S. feltiae (TUR-S3) and Heterorhabditis bacteriophora (Nematop) against a new longicorn pest, Dorcadion pseudopreissi Breuning, 1962 (Coleoptera: Cerambycidae), on turf was examined in laboratory studies. Pathogenicity tests were performed at the following doses: 50, 100 and 150 Dauer Juveniles (DJs)/larva at 25°C. Highest mortalities (75–92%) of the larvae were detected at the dose of 150 DJs/larva for all nematodes used. Reproduction capabilities of the used EPNs were examined at doses of 50, 75, 100 and 150 DJs/larva at 25°C. S. carpocapsae (TUR-S4) had the most invasions (32 DJs/larva) and reproduction (28042 DJs/larva) at the dose of 100 DJs, and the highest reproduction (per invaded DJ into a larva) was observed in H. bacteriophora (Nematop) (2402.85 DJs) at a dose of 50 DJs. The foraging behaviour of the nematodes in the presence of D. pseudopreissi and Galleria mellonella L. (Lepidoptera: Galleriidae) larvae was studied using a Petri dish filled with sand at 20°C. All of the used nematodes accumulated near the larvae section of both insect species (32–53% of recovered DJs) with a higher percentage of S. carpocapsae (TUR-S4) (53%) and H. bacteriophora (48%) (Nematop) moving towards larvae of D. pseudopreissi, than the S. feltiae strains.

Effect of nitrogen fertilization on quality characteristics of four turf mixtures under different wear treatments

ABSTRACT The effect of three nitrogen (N) application regimes on the color, turf quality, cover, and clipping weights of four different sports type mixtures were evaluated under different wear frequencies for three years in an irrigated field. Nitrogen was applied monthly at rates of low (2.5 g N m− 2), medium (5.0 g N m− 2), and high (7.5 g N m− 2). The turf mixtures were subjected to four different wear treatments at frequencies of zero (control), once per week, once biweekly, and once per month for approximately eight months each experimental year. Wear treatments reduced turf color and quality, cover percentage, and clipping yield. Application of wear every week was detrimental to turf characteristics, whereas wear once every month generally had no significant effect. Nitrogen fertilization resulted in improved color and quality, and increased cover percentage and clipping yield.

Effect of Seeding Rate and Nitrogen Fertilization on Proso Millet Under Dryland and Irrigated Conditions

ABSTRACT Proso millet (Panicum miliaceum L.) is a short-season grain crop in semi-arid regions of North and South America and Asia. The objective of this study was to evaluate seeding rates and nitrogen (N) fertilization on proso millet seed yield, crude protein levels, and biomass yield under irrigated and dryland conditions in a Mediterranean-type transition climate near Bursa, Turkey. Seeds per panicle, panicle length, seed weight per panicle, fertile tillers, protein yield, and plant height were also evaluated. Results indicated seeding rate did not affect seed yield significantly. Seed and protein yield increased with increasing N doses although biomass did not significantly increase. Panicle length, seeds per panicle, and seed weight per panicle decreased with increasing seeding rates. This study proved proso millet can be grown for grain and forage as a short-season dryland and irrigated rotational crop in a Mediterranean-type climate.

EFFECTS OF DIFFERENT SEEDING RATES ON FORAGE YIELD AND QUALITY COMPONENTS OF PEA CULTIVARS UNDER BURSA CONDITIONS

The aim of this study was to investigate the effects of seeding rate on yield and quality components in forage pea cultivars. Four pea cultivars (Ulubatli, Kirazli, Golyazi and Urunlu) and five seeding rates (75, 100, 125, 150 and 175 viable seeds m) were used in this study. Field experiments were carried out from 2009 to 2011 during the winter growth period at Uludag University, Faculty of Agriculture, Agricultural Research and Application Center in Bursa, Turkey. The experimental design was a randomized complete block desing with three replications. Dry matter yield, crude protein ratio and yield, acid detergent fiber, neutral detergent fiber, total digestible nutrients and relative feed values were determined. Significant differences were found among the pea cultivars and seeding rates in all measured characteristics in both years. The highest dry matter yield was obtained from the Kirazli cultivar at 125 seed m. The digestibility of the Golyazi cultivar was higher than the other cultivars. On the other hand, the digestibility of the forage decreased as the seeding rate increased.The aim of this study was to investigate the effects of seeding rate on yield and quality components in forage pea cultivars. Four pea cultivars (Ulubatli, Kirazli, Golyazi and Urunlu) and five seeding rates (75, 100, 125, 150 and 175 viable seeds m-2 ) were used in this study. Field experiments were carried out from 2009 to 2011 during the winter growth period at Uludag University, Faculty of Agriculture, Agricultural Research and Application Center in Bursa province, Turkey. The experimental design was a randomized complete block desing with three replications. Dry matter yield, crude protein ratio and yield, acid detergent fiber, neutral detergent fiber, total digestible nutrients and relative feed values were determined. Significant differences were found among the pea cultivars and seeding rates in all measured characteristics in both years. The highest dry matter yield was obtained from the Kirazli cultivar at 125 seed m-2 . The digestibility of the Golyazi cultivar was higher than the other cultivars. On the other hand, the digestibility of the forage decreased as the seeding rate increased.

Effect of plant growth-promoting Bacillus sp. on color and clipping yield of three turfgrass species

ABSTRACT A two-year irrigated field study was conducted to determine the effects of plant growth-promoting rhizobacteria (PGPR; Bacillus subtilis OSU-142 and Bacillus megaterium M3) as biofertilizer, and in combination with a chemical nitrogen (N) fertilizer, on turf color and clipping yield, and interaction of biofertilizer and chemical N fertilizers in perennial ryegrass (Lolium perenne L.), tall fescue (Festuca arundinacea L. Schreb.), and Kentucky bluegrass (Poa pratensis L.). The three turf species were tested separately in split-plot design experiments with three replications. Three fertilizer sources (ammonium nitrate only, ammonium nitrate + B. megaterium M3, and ammonium nitrate + B. subtilis OSU-142) were the main plots. N applications with monthly applications of 0.0, 2.5, 5.0, and 7.5 g N/m2 were the subplots. Color ratings and clipping yields increased with increasing chemical N fertilizers in all species. Both Bacillus sp. significantly increased color ratings and clipping yields in perennial ryegrass and tall fescue. However, there were no significant differences among the three fertilizer sources in color and clipping yield of Kentucky bluegrass. The experiments showed that there is a small but significant benefit from applying biofertilizers for turf color, and that N fertilization may be reduced in some turf species when biofertilization are made for this purpose.