Yield of 'Royal Gala' apple trees in response to pruning before or after leaf drop

Abstract

The objective of this work was to evaluate different pruning times, performed before or after natural leaf drop, regarding their effects on the yield of 'Royal Gala' apple (Malus domestica) trees. The experiment was carried out in Vacaria, in the state of Rio Grande do Sul, Brazil, on seven-year-old trees in four harvests from 2008/2009 to 2011/2012, using a randomized block design. The following pruning times were tested: 46 days before leaf drop (DBLD); 25 DBLD; 5 DBLD; 15 days after leaf drop (DALD); 36 DALD; 55 DALD; and 75 DALD. All pruning times before natural leaf drop reduced yield per tree and fruit set. Among the pruning times before leaf drop, 46 DBLD resulted in the lowest yield. Pruning performed after natural leaf drop, still during dormancy, resulted in a higher yield per tree, in comparison with pruning times before leaf drop. The effect of pruning times on average fruit mass, pulp firmness, content of soluble solids, titratable acidity, and soluble solids/titratable acidity ratio differed between harvest years. Pruning performed at different times, before natural leaf drop, causes yield reduction in 'Royal Gala' apple trees, and the pruning time at 46 DBLD results in the lowest yield.

The Growth Activity and Productivity of Apple Trees Depending on the Form of the Crown and the Time of Pruning

“…Crown pruning during the growth season inhibits vegetative growth (Kweon & Sagong 2022), and according to de Almeida and Fioravanço (2018) and Gościło (2013), increases the fruit yield in the following year. However, according to Bound and Summers (2001), summer pruning reduces the content of dry soluble substances in fruits.…”

Metabolic Response of Malus domestica Borkh cv. Rubin Apple to Canopy Training Treatments in Intensive Orchards

“…Factorial analyses also confirmed the significant dependence of accumulation of carbohydrates in leaves on years (Figure 4). In deciduous plants, such as apple trees, the carbohydrate reserve levels vary during the growth cycle; they are low during the blossom period and the beginning of fructification and high at the end of the growing season [44,52]. During the harvest, sugars are no longer transported to apple fruits; thus, more of them are retained in the leaves and intensively transported in storage locations for the winter [53][54][55][56].…”

Influence of Delaying Winter Pruning on Shoot Growth and Fruit Quality of ‘Fuji’/M.9 Apple Tree

“…사과나무의 정지 및 전정은 대부분 잎이 없는 겨울철 휴면 기에 이루어지는데 [5,6], 이는 휴면기 전정(겨울전정, 동계전 정)의 꽃눈 수 조절에 의한 영양생장과 생식생장의 균형 및 수관 내 광투과율 증진에 대한 효과가 생육기 전정(여름전정, 하계전정)에 비해 높기 때문이다 [6][7][8][9]. 그러나 휴면기(겨울철) 기온이 -20°C부터 -40°C 사이로 내려가기 2주 전에 사과나 무를 강하게 전정하면 동해가 심하게 발생하므로 겨울철에 극심한 저온이 예측될 경우에는 전정을 지연시켜야 하는데, 만약 사과나무를 개화기까지 동계전정을 지연시키면 영양생 장 및 이듬해 개화율이 크게 감소될 위험이 높다 [3].…”