No abstract

Orchard performance is influenced by weed competition. In this study, the effects of weed competition on nutrient contents, chemical and physical fruit quality properties were sought. The study was carried out in a high-density apple orchard ('Golden Delicious'/M.9) over two consecutive growing seasons. The effect of weed competition was studied at three different levels: weak, moderate and strong. Fruit firmness, soluble solids content, macronutrients (such as nitrogen, potassium and calcium) and potassium+magnesium/calcium ratio in fruit were significantly affected by weed competition. Strong weed competition negatively affected soluble solids content and potassium+magnesium/calcium ratio. In both trial years, soluble solids content was significantly higher in weak weed competition. In the first year of the study, soluble solids content ranged between 13.77±0.06% (strong weed competition) and 15.20±0.10% (weak weed competition). In the following year, soluble solids content values were determined as 13.13±0.23% in strong weed competition and 13.83±0.21% in weak weed competition. Weak weed competition showed superiority for fruit weight and potassium+magnesium/calcium ratio. As a whole, this study indicates that insufficient weed control in tree rows might be a limiting factor for fruit quality in high-density apple orchards.

Fruit production has to be adapted to climate change that is often associated with heat and water deficit episodes. To develop efficient strategies on how to manage commercial orchards under deficit water supply, we need to know the effects of water-stress on crop production. However, when the water supply is abundant apple growers often think that over-irrigation gives higher marketable fruit yield than potential evapotranspiration-based or sensor-based (e.g. tensiometer, dendrometer) irrigation. We therefore aimed to evaluate the effects of three water regimes, namely well-watered (100% of crop evapotranspiration -ETc, WW), 25% of ETc water deficit over the season (water-stressed, WS), and twofold of WW (200% of ETc, 2xWW), on midday stem water potential (SWP), crop yield and fruit quality of Pink Lady TM 'Rosy Glow' apples. As expected, SWP was lower in WS than in the others, but both WS and 2xWW decreased fruit yield, although 2xWW tended to increase yield in the >70% color class and ensured quite a constant amount of yield at each picking time. Soluble solid content (SSC) in fruit was higher in WS. As a whole, our results suggest that over-irrigation that is sometimes recommended to keep a safety margin should be considered with caution. Rather, a mild water-stress, between WS and WW in our experiment, may represent a good compromise for a good quality yield.

Son yıllarda dünyada çeşit tanıtımı ve yönetimi oldukça değişmiştir. Meyve endüstrisinde giderek artan rekabet yeni çeşitlerin potansiyel değerini almasını ve korumasını zorlaştırmaktadır. Bu nedenle çalışmada, elma ıslahındaki ilerlemeler, sektörün motivasyonunu etkileyen faktörler, ıslahçı hakları, ticari markalar gibi konulara ışık tutmak ve bunların elma endüstrisini nasıl şekillendirdiğini açıklamak amaçlanmıştır. Sürekli büyüyen bir sektörde yeni çeşitlerin başarı sağlayabilmesi için dikkate alınması gereken birçok faktör vardır. Sektörün ihtiyaçlarını ve tüketicilerin istediklerini anlamak ve bu ikisi arasındaki dengeyi kurmak hayati önem taşımaktadır. Yeni çeşitlerin pazara girmeyi başarabilmeleri için mutlaka sosyal, ekonomik ve ekolojik açıdan üstünlüklerinin olması gerekmektedir. Gelinen noktada yeni çeşitlerin yönetiminde küresel yönetim ve markalaşma kaçınılmazdır. Dolayısıyla ıslah programları küresel sorunları göz önünde tutarak etkin ve verimli ticarileştirme planlarına hızla uyum sağlamak durumundadır. Bu çalışmanın elma ıslah programlarında etkinliği ve bilinci arttırarak, potansiyel risklerin dengelenmesinde faydalı olabileceği düşünülmektedir.

Understanding the attributes of spur leaves in apple trees is essential to gain more insight into the complex process of fruit development and quality. However, limited literature is available about the spur leaf characteristics of the 'Amasya' apple cultivar. In this work, the Soil Plant Analysis Development (SPAD) and leaf area were investigated in flowering and non-flowering spur leaves of 'Amasya' and six common apple cultivars. Significant differences among cultivars were observed for the SPAD and spur leaf area. The median SPAD readings in 'Amasya' were 32.63 and 26.23 for the flowering and nonflowering spurs, respectively, which were the relatively low values among studied cultivars. The maximum SPAD value was measured in flowering spurs of 'Cripps Pink' (45.03). SPAD values were found to be lower in non-flowering spurs compared with flowering ones for all the studied cultivars, which confirms that decline in chlorophyll content coincided with a gradual decline in productivity. A notably significantly lower spur leaf area was found in 'Amasya', whereas the highest spur leaf area was in 'Cripps Pink'. However, no statistical difference was observed between flowering and non-flowering spur leaf areas within the same cultivars. The present results provided a general framework of SPAD and spur leaf areas in 'Amasya' and other apple cultivars when spurs had flowers or not. Knowledge of these characteristics provides a basis for building a model related to yield elaboration of apple trees.