Varieties and their pollinators
A few varieties with recognized importance in different areas of the Galician forests (‘Amarelante’, ‘De Parede’, ‘Famosa’, ‘Garrida’, ‘Longal’, ‘Negral’, ‘Ventura’ and ‘Xudía’) and their pollinators (‘Negral’, ‘Rapada’ and ‘Picona’) were chosen to be planted in new forests of the area covered by the protected geographical indication ‘Castaña de Galicia’. These and other very productive traditional varieties, or with highly appreciated chestnut characteristics in their respective growing areas, are described, such as ‘Raigona’, ‘Luguesa’, ‘Inxerta’, ‘Branca’, ‘Puga de Afora’, ‘De Presa’ e ‘Loura’
Areas of traditional use of varieties
Table 1. Areas of traditional use of the sixteen grafted varieties described..
| Climate zone | Variety | Area of traditionale use | Altitude range(mamsl) |
| Area II: Northern and central interior of Galicia ‘De Parede’ | ‘De Parede’ | Eastern Mountain of ‘Lugo’ (‘Os Ancares’, ‘Folgoso do Courel’) and ‘Mariña de Lugo’ | 550-750 |
| ‘Garrida’ | ‘Chantada’ and ‘Tagoodda’ | 300-600 | |
| ‘Loura’ | Interior of Galicia (‘A Ulloa’, ‘Chantada’, ‘Tagoodda’ and ‘A Fonsagrada’) | 570-650 | |
| ‘Luguesa’ | Eastern mountain of ‘Lugo’, ‘Mariña de Lugo’ and ‘Fragas do Eume’ | 200-750 | |
| ‘Picona’ | ‘Becerreá’, ‘Samos’ and ‘Triacastela’ | 600-700 | |
| Area III:valley ‘Val do Si | ‘Branca’ | ‘Valdeorras’ (‘A Rúa’ and ‘Larouco’); ‘Terra de Castro Caldelas’ and ‘Quiroga’ | 350-700 |
| ‘Negral’ | ‘Valdeorras’ (‘O Barco’, ‘Carballeda’ and ‘Rubiá’) | 320-630 | |
| ‘Raigona’ | ‘Valdeorras’ (‘Carballeda’ and ‘Rubiá’) | 500-600 | |
| Area IV: Eastern mountain range of Galicia | ‘Amarelante’ | ‘Terra de Trives’ (‘Manzaneda’) and ‘Viana do Bolo’ | 550-950 |
| ‘De Presa’ | ‘O Courel’, ‘Os Ancares’ and neighboring municipalities | 700-800 | |
| ‘Famosa’ | Southeast of ‘Ourense’ (‘Gudiña’, ‘Riós’ and ‘Vilardevós’) | 500-950 | |
| ‘Inxerta’ | ‘O Bolo’, ‘Manzaneda’ and ‘Viana do Bolo’ | 570-930 | |
| ‘Longal’ | Southeast of ‘Ourense’ (‘Gudiña’, ‘Riós’ and ‘Vilardevós’) | 770-900 | |
| ‘Puga de Afora’ | ‘O Bolo’ and ‘Larouco’ | 500-800 | |
| ‘Rapada’ | East of Ourense (‘O Bolo’, ‘A Mezquita’ and ‘Viana do Bolo’) | 530-950 | |
| ‘Ventura’ | Southeast of Ourense (‘A Gudiña’ and ‘A Mezquita’) | 800-1000 |
Production characteristics and quality of varieties
Table 2. Description of the sixteen varieties by productive characteristics and quality of chestnut.
| Variety | Date of production | Size of chestnut (fruit) | Penetration of integument | Pericarp tear | Production rate | Conservation | Resistance to borers |
| ‘Amarelante’ | late | medium | a few, shallow | very low | high | very good | very resistant |
| ‘Branca’ | late | medium | a few, shallow | very high | high | good | resistant |
| ‘De Parede’ | medium | small | a few, shallow | low-very low | high | very good | very resistant |
| ‘De Presa’ | medium | big | a lot, fondas | very low-medium | low | bad | limited |
| ‘Famosa’ | late | big | a few, shallow | very low | medium | bad | limited |
| ‘Garrida’ | late | big | a lot, medium depth | very low | low | good | – |
| ‘Inxerta’ | medium | big | a lot, medium depth | very low | low | good | resistant |
| ‘Longal’ | late | medium | nonexistent | low-very low | low | very good | very resistant |
| ‘Loura’ | medium | small | a few, medium depth | very low | medium | good | resistant |
| ‘Luguesa’ | early | medium | a few, fondas | very low-low | high | good | resistant |
| ‘Negral’ | early | medium | a few, medium depth | very low | high | very good | very resistant |
| ‘Picona’ | medium | medium | a few, medium depth | low | medium | good | resistant |
| ‘Puga de Afora’ | medium | small | a few, medium depth | very low | low | good | very resistant |
| ‘Raigona’ | medium | medium | a few, shallow | very low | high | very good | very resistant |
| ‘Rapada’ | medium | small | a few, medium depth | very low | high | good | resistant |
| ‘Ventura’ | early | small | a few, shallow | very low | medium | good | very resistant |
Characteristics of pollinators
Varieties can be classified into four morphological types according to the length of filaments of the anthers, feature related to the amount of pollen contained in the anthers
- The longiestaminate inflorescences (with abundant pollen) have long filaments (> 5 mm) and produce a lot of pollen. Much of native chestnut are this type, but there are very few varieties with longiestaminate (Figure 7):
- The mesostaminate inflorescences (with low pollen) have short filaments (3-5 mm) and produce varying amounts of pollen.
- The brachystaminate inflorescences have very short filaments (
- The astaminate, inflorescences, without anthers, are totally sterile and fall prematurely without end forming.
For a good chestnut (fruit) production is required the presence of two pollinator varieties that meet the following requirements:
- They should be producers of abundant pollen, preferably ‘longiestaminates’. Among the recommended varieties for new plantations, only ‘Negral’ is ‘longiestaminate’; other chosen varieties produce little pollen (‘Amarelante’, ‘De Parede’, ‘Famosa’ and ‘Xudía’) or none (‘Garrida’ and ‘Longal’). Other interesting ‘braquiestaminadas’ varieties (eg ‘Raigona’, ‘Inxerta and ‘Luguesa’) aren’t major producers of pollen, although they produce a little, especially the last two. Consequently, three other varieties were chosen as potential pollinators; two of them, ‘Picona’ and ‘Serodia’, produce a lot of pollen; ‘Rapada’ is ‘mesoestaminado’, but it is a producer of abundant pollen. In the collection of varieties, there are some more ‘longiestaminado’ varieties, such as ‘De Lemos’, that could be tested as pollinator.
- There should be an acceptable synchronization between the emission of pollen, from the inflorescences of pollinator varieties, and the receptivity of the female flowers of the producing varieties. The pollen vectors are wind and insects. The varieties chosen as pollinator differ at the most in eight days on the dates of beginning of the issuance of the pollen. The earliest ones are ‘Serodia’ and ‘Picona’; ‘Negral’ is intermediate; and the ‘Rapada’ is later. Regarding the start of the receptivity of female flowers, the differences between varieties also reach about eight days at most; the earliest are ‘Rapada’ and ‘Ventura’; the latest varieties are ‘Amarelante’, ‘Famosa’ and ‘Garrida’, that have got a better synchronization with ‘Rapada’ than with other pollinators. Anyway, there are two facts that suggest that the lack of a perfect synchronization is not a fatal problem for pollination. One is that the receptivity of stigmas remains for a long period of time, about three weeks; the other is that pollen retains its viability for at least for five weeks after their release, although it is unknown if bees and other pollen vectors act when the inflorescences are wilted.
- Pollinators should have genetic compatibility with producing varieties, a feature that is determined by controlled pollinations. In tests with the Galician varieties ‘Amarelante’, ‘Famosa’, ‘Longal’, ‘Negral’, ‘De Parede’, ‘Garrida’ and ‘Ventura’, it is shown that the varieties ‘Picon’, ‘Serodia’ and ‘Negral’, all ‘longiestaminate’, have a good compatibility with the others, and that is why these three varieties can act as pollinators of all the tested varieties. The best results have been obtained with ‘Picon’ and ‘Serodia’. Only in the variety ‘Garrida’ best results were obtained with ‘Negral’.
