Two years of research were carried out to evaluate the effects of various sewage sludge and nitrogen doses on the turf performance of perennial ryegrass (Lolium perenne L.) under Mediterranean-type climatic conditions. Four nitrogen sources (NS) [NS1: ammonium nitrate (26%), NS2: Bursa City’s wastewater treatment plant’s waste, NS3: biogas production plant reactor waste, and NS4: food processing and canning factory’s sludge waste] were used in the research. Four different nitrogen doses (0.0, 2.0, 4.0, and 6.0 g m⁻²) were applied. The sewage sludges were analyzed before the start of the research. It was determined that the heavy metal concentrations were below the limit values, and the plant nutrient content was high. Turfgrass color and quality observations were taken in the study, and turfgrass clipping yield was determined. The 4.0 g m⁻² nitrogen dose provided acceptable turf color and quality values among the sewage sludges. NS4 showed the best turf performance among the sewage sludges. Despite increased turf color and quality values, sewage sludge produced a low clipping yield. Food processing and canning factories’ sewage sludges can be alternatives to a nitrogen source.

Doubled haploid technology has become an increasingly popular and important tool for developing new maize lines (Zea mays L.) breeding. Conventional maize breeding requires repeated self-pollination for about six to ten generations to obtain homozygous inbred lines. Completely homozygous lines can be produced in only two generations by using doubled haploid technology. In vivo induction of the maternal haploid method was used for the production of doubled haploid lines. 32 different donors pollinated with haploid inducer line Stock6. Haploid seeds were identified visually by using dominant anthocyanin color marker genes R1-nj. Haploid induction rates (HIR) and chromosome doubling rate (CDR) were determined. 488 putative haploid seeds were obtained. The average haploid induction rate was calculated as 2.0%, the average chromosome doubling rate was 52,3%. Results of this study 20 doubled haploid lines were developed.

Background: Maize (Zea mays L.) is a widely cultivated cereal crop for silage production due to its high biomass yield and nutritional value. Developing high-yielding and nutritionally superior hybrids is increasingly vital in the face of climate change and rising global forage demand. Doubled haploid (DH) technology accelerates hybrid development by enabling the rapid production of fully homozygous pure lines. This study aimed to evaluate silage maize hybrids derived from DH inbred lines for the effects of yield and nutritional quality. Methods: Eight recently developed hybrids (derived from doubled haploid inbred lines: S1, S2, S6, S9, and S11; derived from conventional inbred lines: S7, S8, and S10) and four commercial silage checks (S3, S4, S5, and S12) were used in this study. The experiments were arranged in a randomized complete block design with three replications. In this study, agronomic traits including plant height, ear ratio, stem ratio, and forage yield were evaluated, along with forage quality parameters such as dry matter, crude protein, neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL), and relative feed value. Results: Genotypes S6 and S9 provided higher forage yield, plant height, ear ratio, and a lower stem ratio. All genotypes of dry matter, crude protein, NDF, and ADF values were within the desired range. DH-derived hybrids outperformed checks and those derived from conventional inbred lines regarding forage yield and the investigated agronomic traits. The DH technology has great potential in developing high-yielding hybrids in a short time in silage maize breeding.

This research was conducted to determine the effects of different nitrogen sources and rates on some warm-season turfgrasses under Mediterranean-type climate conditions in 2017-2018. The experimental design was a split-split plot with design with three replicates; turfgrass species as the main plot, nitrogen sources as the subplots, and nitrogen doses as the sub subplots. The main plots consist of four nitrogen sources: two slow-release fertilizers, one organomineral fertilizer, and one sewage sludge. Subplots consist of three warm-season turfgrass species; zoysiagrass (Zoysia japonica Steud.), hybrid Bermudagrass (Cynodon transvaalensis x Cynodon dactylon), seashore paspalum (Paspalum vaginatum Sw.), and one cool-season turfgrass species, tall fescue (Festuca arundinacea Schreb.). The nitrogen doses were as follows; 0.0, 2.0, 3.0 and 4.0 g m-2. Turf color and quality were evaluated visually monthly. Also, clipping weight is determined. According to the result, slow-release and organomineral fertilizers can be assessable as N sources that will meet the nutritional needs of the turfgrasses. Zoysiagrass and seashore paspalum showed almost equivalent scores and gave sufficiently dark turf color and quality. Turfgrass should be fertilized at least with 3.0 g m−2 N to provide acceptable turf color and quality.

This study was carried out to determine the forage production potentials of different sweet sorghum genotypes under Mediterranean-type climate conditions as the second crop in 2020. Three different sweet sorghum genotypes (Erdurmuş, Uzun varieties, and M81-E line) and four nitrogen doses (0.0, 7.5 12.5, 17.5 kg da-1) were used in this research. The experimental design was a randomized complete block with three replications. Some parameters such as plant height, stem diameter, plant number per m2, leaf number, leaf and stem ratio, forage yield, and dry matter yield of sweet sorghum genotiyps were investigated in the experiment. According to the results, M81-E gave the highest values in terms of stem diameter, leaf number, forage yield, and dry matter yield parameter compared to other genotypes. Forage yield values of the genotypes were between 2969.9 and 5815.0 kg da-1 and dry matter yield values were 1105.7 and 2837.8 kg da-1. Forage yield values vary between 2920.1 and 4674.6 kg da-1 for the nitrogen doses. The highest forage yield was obtained at 12.5 and 17.5 kg da-1 nitrogen doses, which were in the same statistical group. Fertilization can be made with a 12.5 kg da-1 nitrogen dose in sweet sorghum due to the negative environmental effects of chemical fertilizers.

This research was conducted to determine to effects of different irrigation levels and nitrogen doses on the various warm-season turfgrasses at DELETED by JAS for two years in a row. The experimental design was the randomized blocks in a split-split plot design with three replications. The main plot was irrigation levels (I1=25%, I2=50%, I3=75%, and I4=100% of pan evaporation), subplots were turfgrass species [hybrid Bermudagrass (Cynodon transvaalensis x Cynodon dactylon) cv. Tifdwarf, seashore paspalum (Paspalum vaginatum Sw.) cv. Seaspray, zoysiagrass (Zoysia japonica Steud.) cv. Zenit], and sub subplots were nitrogen doses (monthly 0.0, 1.25, 2.5, and 5.0 g N m-²). Visual turfgrass color and quality, clipping yield, leaf relative water content, loss of turgidity, chlorophyll content, and electrolyte leakage were measured. According to the results, significant differences were determined among irrigation levels, turfgrass species, and nitrogen doses for color, quality, clipping yield and physiological parameters. Turfgrass visual color, quality and clipping yield were shown to decrease significantly with decreases in irrigation water and N fertilizer. The study findings demonstrated that under a non-limiting water supply, irrigation could be decreased by adjusting N fertilizer rates with I3N3 treatments can maintain acceptable turfgrass visual color and quality under Mediterranean climatic conditions. In addition, at 25%(I1) deficit irrigation level, leaf relative water content, chlorophyll content decreased significantly, while an increase was determined in loss of turgidity. This research indicated that under 75%(I3) deficit irrigation and N3 nitrogen dose, acceptable quality can be maintained with ‘Seaspray’ seashore paspalum under Mediterranean climate performed.