EVALUATION OF YIELD EFFICIENCY AND WINTER HARDINESS OF QUINCE ROOTSTOCKS FOR 'CONFERENCE' PEAR

F. Maas
The aim of this study was to compare and evaluate the effect of five different types of quince rootstocks on the growth, production efficiency and fruit size of ‘Conference’ pears. Next to the standard rootstocks MC and Adams, C.132, MH and Eline® were used. Trees were planted at two different locations in The Netherlands, in the experimental orchard of Applied Plant Research, Wageningen UR in Randwijk and in a commercial orchard in Krabbendijke. Trees were grown for five years with (Randwijk) or without (Krabbendijke) fertigation.
No differences were observed between trunk growth of ‘Conference’ grafted on these five rootstocks. In Randwijk shoot growth was the highest and comparable for trees on Adams, Eline® and MC. Significantly less shoot growth was observed for trees on quince MH. The level of shoot growth on C.132 was between that on MH and the other three quince types.
Independent of rootstock, fruit production started in the second year after planting of the two year old nursery trees in the orchard. The highest initial yields were observed for trees on Adams, MC and Eline®, a somewhat lower production on C.132 and the lowest for trees on MH. Cumulative yields per tree over 5 years amounted to 50 kg for trees on Adams, MC and Eline®, 36 kg on C.132 and 35 kg on MH with a similar average fruit weight of 216 g and 73% of the yield consisting of fruits with a diameter >65 mm. ‘Conference’ on Eline® produced fruits with significantly less russeting than on any of the other quince rootstocks.
A severe frost period in February 2012, with temperatures down to -23°C, caused damage only to trees of which the rootstock shank was not protected by a layer of compost during the winter. Immediately after the frost period the degree of damage, judged on basis of the amount of brown discoloration of the bark tissue, was the highest in Adams and MC, intermediate in Eline® and MH, and absent in C.132. However, at the end of August 2012 a large proportion of the trees on C.132 that had not been covered by compost showed leaf yellowing and reduced vigour. These symptoms were not observed on any of the other unprotected rootstocks. In 2013 five of the eighteen trees on unprotected C.132 died. In September 2013, 19 months after the frost period, Eline® had the darkest green leaves and showed the least brown discoloration of all five types of quince rootstocks that had not been protected by a layer of compost during the winter. No differences in leaf colour or any brown discoloration of the bark tissue was observed in any of the five types of quince that had been covered by compost during the winter.
The initial production levels of the non-fertigated trees in Krabbendijke were much lower than those of the fertigated trees in Randwijk. Without fertigation the production was the highest on quince Adams, about 30% higher than on MC and Eline®. Yields on C.132 and MH were 35 and 65% lower than on MC. Fruit size was also less for trees grown without fertigation. Quince Adams produced the highest proportion of fruits in the size class >65 mm (64%) and MH the lowest (53%).
In conclusion, in the fertigated orchard ‘Conference’ produced the best and alike on Adams, MC and Eline®. Without fertigation Adams proved the most productive rootstock followed by MC and Eline®. Eline® proved to be the most frost resistance rootstock when rootstock shanks were not covered by compost during the winter.
Maas, F. (2015). EVALUATION OF YIELD EFFICIENCY AND WINTER HARDINESS OF QUINCE ROOTSTOCKS FOR 'CONFERENCE' PEAR. Acta Hortic. 1094, 93-101
DOI: 10.17660/ActaHortic.2015.1094.8
https://doi.org/10.17660/ActaHortic.2015.1094.8
Cydonia oblonga, Pyrus communis, frost damage, Adams, C.132, MC, MH, Eline®, russeting
English

Acta Horticulturae