Nyska R.,Galilee Scientific Research Institute |
Nyska R.,Hebrew University of Jerusalem |
Shafir S.,Hebrew University of Jerusalem |
Goldway M.,Galilee Scientific Research Institute |
And 2 more authors.
Scientia Horticulturae | Year: 2014
Loquat (Eriobotrya japonica Lindl.), a member of the Rosaceae, carries the RNase-dependent gametophytic self-incompatibility (GSI) fertilization system. However, some cultivars, including the Israeli 'Yehuda' and 'Akko 1', are self-compatible (SC). Since SC cultivars are not dependent on pollen donors, they are usually planted in 'solid blocks'. Nevertheless, in some SC Rosaceae species, such as apricot, cherry and almond, enhanced self- or cross-pollination increases fruit set. To determine whether enhanced pollination can improve 'Yehuda' and 'Akko 1' fruit set and fruit size relative to spontaneous self-pollination, the impact of introducing honey bees and the effect of cross-pollination were examined. We found that honey bees are highly attracted to 'Yehuda' and 'Akko 1' flowers, and fruit size in both cultivars was positively correlated with the number of seeds per fruit. In a net-caged tree experiment, fruit set of 'Yehuda' and 'Akko 1' benefited from the presence of honey bees. However, fruit set was also relatively high for the caged trees without honey bees which underwent spontaneous self-pollination, and commercial fruit thinning was required for all treatments. For both cultivars, seed set after spontaneous self-pollination was the same as for self-pollination in the presence of honey bees. The impact of cross-pollination between different cultivars moderately increased 'Yehuda' fruit set and 'Akko 1' seed set. Taken together, the results suggest that spontaneous self-pollination meets the pollination requirements for the SC loquat cultivars 'Yehuda' and 'Akko 1', and that the presence of pollen donors and/or honey bees confers a minor commercial advantage. © 2014 Elsevier B.V. Source
Raz A.,Galilee Scientific Research Institute |
Raz A.,Hebrew University of Jerusalem |
Stern R.A.,Galilee Scientific Research Institute |
Stern R.A.,Galilee College |
And 3 more authors.
Journal of Horticultural Science and Biotechnology | Year: 2014
The European apricot (Prunus armeniaca) cultivar ‘Earlicot’ has high economic potential due to its high-quality fruit and early yields. ‘Earlicot’ has recently been introduced into Israeli orchards. The climate in Israel is relatively warm, although cold enough for cultivating high-quality stone fruit. However, the full potential of this new apricot cultivar was not being realised. The aim of this work was to understand the reasons for the low performance of ‘Earlicot’ and to identify methods to overcome them. In a 2-year study, we observed that ‘Earlicot’ flowered poorly. The problem of poor flowering and hence fruit-set was improved and yields tripled following application of the gibberellin inhibitor, uniconazole, at 500 mg l–1 [1% (v/v) Magic™] during the period of floral differentiation (mid-May). In addition, we found significant positive relationships between the proximity of ‘Earlicot’ trees to the polleniser ‘Earlygold’ and the efficiency of fertilisation, as determined by the genetic marker S8-RNase, the fruit-set percentage, and fruit yield. We also identified the early apricot flowering cultivar ‘311’ to be a fully-compatible polleniser for ‘Earlicot’. Fullcompatibility for cross-pollination will assure high fruit yields in ‘Earlicot’. © 2014 Journal of Horticultural Science & Biotechnology. All rights reserved. Source