Ligol

History

Ligol was selected in 1972 at the Research Institute of Pomology and Floriculture in Skierniewice by Andrzej Przybyła and Stanisław W. Zagaja^1,2. The institute’s catalogue names Jan Krzewiński as a third selector and records that the seedlings came from a cross of Linda and Golden Delicious made by Wacław Dzięcioł; Ligol’s breeding number was XIX-148-D1¹. Ligolina, also known as Ligol’s Sister, has the same parents and was selected by the same three in 1972 from a cross Dzięcioł made in 1963¹.

Ligol was entered in Poland’s national register on 14 April 1997³, and from that year it was also protected by plant breeders’ rights². Its share of the country’s apple-orchard area grew from 1.1 per cent in 1998 to 7.0 per cent in 2017, when it ranked fourth, after Idared, the Jonagold group and Šampion⁴.

The fruit

The fruit is large or very large, round-conical and distinctly ribbed around the eye^1,2. The tough, glossy, slightly greasy skin is greenish, turning yellow as it ripens, with a bright red flush over 40–70 per cent of the surface¹; on the sunny side a carmine-red flush can cover it completely². The flesh is cream, crisp, juicy and aromatic, sweet with some acidity^1,2. In the institute’s 2018 study, fruit picked for long storage had 11–12 per cent soluble solids and 0.4–0.5 per cent acidity, but fruit without a flush often had no more than 10 per cent, and such fruit is judged tasteless².

In Poland it is picked at the end of September or in the first ten days of October and eaten from late January until March or April¹. For long storage the institute advises picking at a starch index of 6–8, when the fruit is usually 65–70 N firm². Its 2018 storage study found that Ligol keeps three to four months in a normal atmosphere, up to eight in ultra-low-oxygen stores at 0–1 °C, and up to twelve there after treatment with 1-methylcyclopropene (1-MCP)². In store it is very prone to grey mould and bitter rot¹.

Growing

The tree is moderately vigorous, with a strong pyramidal crown made dense by many spurs and large leaves¹; the shade this casts hinders the fruit’s colouring². It flowers in mid-season, is diploid, and is a good pollinator of varieties flowering at the same time¹. It bears very early and heavily but tends to crop in alternate years¹. The fruit is prone to bitter pit; the tree is moderately susceptible to scab and powdery mildew, very susceptible to fire blight, and fairly hardy to frost¹.

Uses

Ligol is a dessert apple¹. Under the EU marketing standard it belongs to colour group B, so fruit of the Extra class must be flushed over at least half its surface².

Where the sources disagree

• Who selected it. The institute’s 2018 storage study names Przybyła and Zagaja²; its 2013 catalogue adds Krzewiński¹.
• Storage. The 2013 catalogue gives six months in cold store¹; the 2018 study gives three to four months in a normal atmosphere, unless the fruit is treated with 1-MCP or kept in a low-oxygen store².