APS-Journal Jan 2017

M andarin

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Table 3. Fruit weight and soluble solids concentration of Robinson OP ‘GS’ × C. kinokuni segregating population for genetic seedlessness Fs as separated by presence or absence of fruit neck. Phenotype Genotypes (no) Fruit (no) Weight (g) SSC (%) Neck 138 396 100.31 a z 8.95 a Flush (no neck) 40 108 100.70 a 9.05 a z Similar letters within a column indicates means not significantly different, Tukey’s test, α=0.05.

SSC (Table 3). However, this characteristic was associated with the mean fruit weight in the ’G96-01’ × C. kinokuni ‘Mukaku kishu’ PI539530 segregating population, with fruit from genotypes with enlarged neck having an average weight of 90.7g in comparison with their flush counterparts of 137.9g. Sim- ilarly, fruit from genotypes with a neck had a SSC of 9.7 in comparison with fruit with no neck with an average SSC of 10.2. For all the segregating populations SSC was not corre- lated with fruit weight. Conclusions  In the pursuit of developing a seedless cit- rus cultivar with a heritable seedless trait, it is important to identify and understand any affects that this trait may have on fruit size and sugar content. The research presented shows that the four families of F1 breed- ing populations segregating for the seedless ( Fsfs ) trait, have no significant difference in fruit weight (g) or SSC (%) from their seeded counterparts. In addition, the presence of a neck at the stem segregated in a 3:1 (+/-) fashion among these populations. This trait had no consistent effect on the measured pa- rameters in this study. Literature Cited Chao, C.C.T. 2005. Pollination study of mandarins and the effect on seediness and fruit size: impli- cations for seedless mandarin production. Hort- Science. 40:362-365. Chavez, D. J. and J.X. Chaparro. 2011. Identification of Markers Linked to Seedlessness in Citrus kinokuni hort. ex Tanaka and Its Progeny Using Bulked Seg- regant Analysis. HortScience. 46:693-697.

Denney, J. O. and G.C. Martin. 1990. Xenia and metaxenia: definitions and other boundaries. Hort- Science. 25:1169-1169. Futch, S. H. and L.K. Jackson. 1993. Pollination of Citrus Hybrids. UF/IFAS. EDIS Doc.#HS182. García-Martínez, J. L. and M.A. García-Papí. 1979. The influence of gibberellic acid, 2, 4-dichloro- phenoxyacetic acid and 6-benzylaminopurine on fruit-set of Clementine mandarin. Scientia Hort. 10:285-293. García-Papí, M.A., and J.L. García-Martínez. 1984. Endogenous plant growth substances content in young fruits of seeded and seedless Clemen- tine mandarin as related to fruit set and develop- ment. Scientia Hort. 22:265-274. Hearn, C. J., P.C. Reece, and R. Fenton. 1968. Effects of pollen source on fruit characteristics and set of four citrus hybrids. Proc. Fla. State Hort. Soc. 81:94-98. Khan, I. A. (Ed.) 2007. Citrus genetics, breeding and biotechnology. CABI. pp. 198-205. Nesumi, H., M. Nakano, and T. Yoshida. 2001 Mode of inheritance on the abnormal development of impregnated ovules derived from Mukaku-kishu. J. Jpn. Soc. Hor. Sci. 70 (Suppl. 2):403 (abstr) [in Japanese]. Spiegel-Roy, P. and E.E. Goldschmidt. 1996. The biol- ogy of Citrus. Cambridge Univ. Press. pp. 41. Vithanage, V. 1991. Effect of different pollen parents on seediness and quality of ‘Ellendale’tangor. Sci- entia Hort. 48:253-260. Wallace, H. M. and L.S. Lee. 1999. Pollen source, fruit set and xenia in mandarins. J. Hort. Sci. Biotech- nol. 74: 82-86. Wallace, H. M., B.J. King, and L.S. Lee. 2002. Pol- len flow and the effect on fruit size in an 'Imperial' mandarin orchard. HortScience 37:84-86. Yamasaki, A., A. Kitajima, N. Ohara, M. Tanaka, K. Hasegawa. 2009. Characteristics of arrested seeds in Mukaku Kishu-type seedless citrus. J. Jpn. Soc. Hor. Sci. 78:61-67.