Effect of plant density and shading applications on yield and yield components in faba bean (Vicia faba L.) varieties

This research was conducted over two years, from 2022 to 2023, in the trial area of Dicle University Faculty of Agriculture, Diyarbakir, Turkiye. The study was aimed to determined the effect of different plant densities and shading on the yield and yield components of some faba bean (Vicia faba L.) varieties. In the study used three faba bean varieties (Emiralem, Kuşadası, and Sorgun), two plant densities (10 plants/m2 and 20 plants/m2) and four shading applications (0%, 40%, 75%, and 95%). The experiment was arranged to the randomized complete blocks in split-split plot design with three replications. Main plot treatments consisted of cultivars. Sub-plot treatments were plant density. Sub-subplots treatments were also plant shading traetments. In the research; In order to examine the effect of variety, plant density and shade applications, yield and yield characteristics of freshly harvested plants and post-harvest plants during pre-flowering, full flowering and pod setting periods for two years, and growth parameters of vegetative characteristics were examined in seven different development periods in 2022. Plant traits such as plant height (cm), number of pods per plant, weight of pods per plant (g), number of seeds per plant, number of seeds per pod, and grain yield (kg/da) were examined. According to the combined analysis year, variety, plant density and shading treatments, year x variety, year x plant density, year x shading, variety x plant density and plant density x shading interactions for grain yield were significant. The highest grain yield of 155.53 kg/da was obtained from of 20 plants/m2, while the highest values of the number of pods and seeds per plant were obtained from a density of 10 plants/m2. However, as plant densities increased, yield characteristics decreased. For shading applications, the highest grain yield (184.79 kg/da) was in the 40% application, while the lowest seed yield (107.06 kg/da) was recorded in the 95% application. Intensive shading increased plant height but caused the plant stems to become spindly. Moderately shaded and unshaded plants had a higher number of pods, seeds per plant and grain yield than heavily shaded plants. The time to reach the CGR peak is the 53rd and 60th days in both plant densities. It was determined that 95% shade application did not achieve peak CGR value even during the flowering and pod setting periods, growth was delayed and it reached the highest value on the 67th day. Leaf area index reached its highest value in both plant frequencies on the 60th and 67th days. On the 32nd day, the LAI was 1.3 m2/m2 in 95% shading and 1.45 m2/m2 in 75% shading, while similar leaves were observed in 40% (1.22 m2/m2) and open field (1.16 m2/m2) applications. area index was determined.