AYA and HANA: New Seedless Mandarin’s Triploid Hybrids Selected in Morocco

Seedlessness is a major objective in Morocco Citrus improvement programme. Triploidy has played
an important role in the development of new seedless mandarin cultivars for fresh fruit market and has
received increasing attention for the consumers. Citrus triploid hybrids can be recovered through 2x x
2x taking advantage of the unreduced (2n) gametes formation. 2x x 4x and 4x x 2x sexual
hybridizations are also widely exploited. In that case, many series of diploid crosses were assessed.
At maturity, the fruits have been harvested, and small embryos were extracted from undeveloped
seed and cultured on the medium of Murashig and Skoog supplemented with 1mg/l gibberellic acid
according. Triploids seedling selected by flow cytometry analysis were budded on Troyer citrange and
planted in INRA domain with spacing 6 m X 3 m. Two new seedless selections of mandarins have
been evaluated in a citrus breeding program at Morocco INRA: Hana and Aya that were compared
with their female parent clementine Sidi Aissa. These promising seedless mandarins were identified
by easy-peeling, juicy fruits, have a pleasant taste and are sweet like the Sidi Aissa Clementine.
These clones, showing commercial interest, were described and registered in Moroccan official
catalogue. Triploidy confirmed its importance in obtaining seedless hybrids. This study is significant
because it is the first triploids Citrus selection work in Menzeh INRA in Morocco. We found
considerable differences most of the pomological characteristics. To make an objective comparison of
fruit quality, precocity, and yield of these selected genotypes, they all need to be grown using many
rootstocks, soils, climates, and cultural practices. Adaptation studies will also be required for the
selected mandarins triploids. Therefore, selected in the first stage of selection should be studied in the
second stage of selection.