Mevlüt Türk

Effects of phosphorus fertilisation and harvesting stages on forage yield and quality of narbon vetch

Abstract The effects of five different phosphorus rates (0, 30, 60, 90 and 120 kg ha‐1) and three different harvesting stages (beginning of flowering, full flowering, and seed filling) on forage yield and quality of narbon vetch (Vicia narbonensis L.) were evaluated under the Mediterranean conditions of Turkey in 2005 and 2006 growing seasons. Dry matter (DM) yield, crude protein (CP), N, P, K, Mn, Cu, Fe, Zn, Ca, Mg, acid detergent fibre (ADF) and neutral detergent fibre (NDF) were determined. Phosphorus rates and harvesting stages significantly affectedmost of the quality components determined in narbon vetch. Phosphorus applications increased DM yield, CP, N, P, Ca and Mg contents, decreased K, Fe, ADF and NDF, and had no effect on Mn, Cu and Zn. Harvesting at the late stages caused a reduction in forage quality. Crude protein, N, P, K, Cu, Zn and Mg contents decreased with advancing stages, while Ca, ADF and NDF contents increased.

Effects of fertilisation and harvesting stages on forage yield and quality of hairy vetch (Vicia villosa Roth.)

Abstract This study aimed to determine the effects of five phosphorus rates (0, 30, 60, 90 and 120 kg ha‐1) and three harvesting stages (beginning of flowering, full flowering, and seed filling) on forage yield and quality of hairy vetch (Vicia villosa Roth.). Dry matter (DM) yield, N, P, K, Mn, Cu, Fe, Zn, Ca, Mg, acid detergent fibre (ADF) and neutral detergent fibre (NDF) were determined. Phosphorus rates and harvesting stages significantly affected most of the components determined in hairy vetch. Phosphorus applications increased DM yield, N, P, Ca and Mg contents but decreased K, tetany ratio (K: (Ca + Mg)), ADF and NDF and had no effect on Mn, Cu, Fe and Zn. Harvesting at the late stages caused a reduction in forage quality. Contents of N, P, K, Cu, Zn, Mg and tetany ratios decreased with advancing growth while DM yield, Ca, ADF and NDF contents increased.

Use of canopy-and leaf-reflectance indices for the detection of quality variables of Vicia species

Laboratory determinations of plant-nutrient contents are time consuming and costly. Measurements of reflectance may provide a rapid and accurate means of estimating plant quality variables. This study was conducted to determine relationships between nitrogen (N), phosphorus (P), potassium (K), acid detergent fibre (ADF) and neutral detergent fibre (NDF) contents of Vicia sativa, Vicia pannonica and Vicia villosa and their canopy- and leaf-reflectance indices. Canopy- and leaf-reflectance measurements were made by using a portable spectroradiometer and a plant probe. Linear equations between each forage quality variable and the simple ratio of reflectances in the near-infrared (R NIR) to red regions (R Red) of the electromagnetic spectrum, R NIR/R Red, or the normalized difference vegetation index, NDVI, had coefficients of determination, R 2, of 0.45 ≤ R 2 ≤ 0.80 and 0.49 ≤ R 2 ≤ 0.85 at wavelengths of 760 and 640 nm, respectively. Validation of developed equations indicated that all quality parameters could be predicted by either NDVI or R NIR/R Red. Our results suggest that N, P, K, ADF and NDF contents of vetch species can be estimated at the beginning of the flowering stage and throughout the seed-filling stage using remote-sensing data of both canopy- and leaf-reflectance indices.

EROSION AND MEADOW-PASTURE RELATIONSHIPS

Erozyon, jeolojik surec icerisinde ruzgar ve suyun etkisi ile olusan dogal bir olaydir. Turkiye, erozyonun dunyada en fazla goruldugu ulkeler arasinda yer almaktadir. Erozyonun tamamen onlenmesi imkansizdir. Ancak belli yontemler uygulanarak etkisi ve hizi azaltilabilir veya kontrol altina alinabilir. Bu yontemler arasinda yanlis tarim uygulamalarina, meralarda asiri ve erken otlatmaya, mera ve orman alanlarinin tahrip edilmesine son verilmesi ve agaclandirma faaliyetlerinin artirilmasi yer almaktadir. Bu yontemlerin yaninda asiri otlatmaya dayanikli, kendini cabuk yenileyebilen, gelismis kok yapilariyla topragi siki tutan, su ve ruzgar erozyonuna karsi koruma saglayabilen ve topraga organik madde kazandiran yem bitkilerinin ekilmesi erozyonun siddetini buyuk olcude azaltacaktir. Anahtar Kelimeler: Erozyon, Cayir, Mera, Yem bitkileri