Induction of sex expression and genetic variability of melon (Cucumis melo L.)

Dinja (Cucumis melo L.) je ekonomski značajna jednogodišnja vrsta koja se gaji širom sveta. Pripada familiji Cucurbitaceae, koja pored ove uključuje i nekoliko drugih ekonomski važnih vrsta. Cilj ovog rada je bio da se izdvoji selekcioni materijal koji se odlikuje poželjnim osobinama, da se izvrši analiza nasleđivanja i odrede dobri kombinatori, da se oceni divergentnost uzoraka dinje uz pomoć molekularnih markera i da se utvrdi hemijsko jedinjenje sa najjačim dejstvom na promenu pola. Sva ispitivanja su sprovedena u toku dve vegetacione sezone (2010 i 2011) na 31 genotipu dinje (9 roditelja i 22 hibrida). Za ispitivanje ekspresije pola su korišćeni etrel, srebro nitrat i giberelinska kiselina. Karakterizacija prema UPOV deskriptoru je 31 genotip dinje podelila u grupe na osnovu ocena 6 grupa osobina. Utvrđen je veliki diverzitet između posmatranih genotipova kod većine posmatranih osobina. Izvršena je evaluacija 24 osobine dinje koje su bile podeljene u 4 kategorije: 1) morfološke osobine, 2) osobine polne ekspresije, 3) osobine ploda, 4) osobine kvaliteta ploda. Na osnovu rezultata ovih evaluacija određeni su genotipovi roditelja i hibrida sa maksimalnim i minimalnim vrednostima za sve posmatrane genotipove. Takođe, između genotipova hibrida su utvrđeni oni sa najboljim kombinacijama osobina. Morfološke osobine, osobine polne ekspresije i osobine kvaliteta ploda su nasleđivane na 6 ili čak svih 7 postojećih načina. Osobine ploda su nasleđivanje dominacijom boljeg roditelja. Kod posmatranih genotipova dinje je utvrđena pojava heterozisa. Najveća vrednost heritabilnosti u širem smislu za morfološke osobine i kod roditelja i kod potomstva je zabeležena za osobinu dužina peteljke ploda. Kod svake od posmatranih morfoloških osobina, osobina ekspresije pola, osobina ploda i osobina kvaliteta ploda se izdvojilo nekoliko genotipova sa dobrim OKS...Melon (Cucumis melo L.) is economically significant annual plant grown all around the world. It belongs to family Cucurbitaceae, which includes several other economically important species. The aims of this study were to: separate the breeding material with desirable properties; to analyze the inheritance mode and determine the good combiners; to assess the diversity of melon genotypes using molecular markers and to determine the chemical compound with the strongest effect on the sex expression. All tests were conducted during two vegetation seasons (2010 and 2011) on 31 melon genotype (9 parents and 22 hybrids). For the research of sex expression ethrel, silver nitrate and gibberellic acid were used. Characterization by UPOV descriptor divided 31 melon genotypes in 6 groups according to their traits. For most observed traits, a large diversity among the researched genotypes was found. Twenty-four melon traits were evaluated and divided into 4 groups according to: 1) morphological traits, 2) sex expression traits, 3) fruit traits and 4) fruit quality traits. Based on the results of this evaluation was determined the parent genotypes and hybrids with maximum and minimum values for all observed genotypes. Also, among the hybrid genotypes those with the best combination of features were determined. Morphological, sex expression and fruit quality traits were inherited in 6 or even 7 existing ways. Fruit traits were inherited by domination of the better parent. The heterosis was found in the researched melon genotypes. The highest value of heritability in broader sense for morphological traits, both for parents and for progeny, was found for trait length of the stem. For all the researched morphological traits, sex expression, fruit and fruit quality trait, several genotypes with good general combining ability were distinguished. Based on the results of principal components analysis a significant connection between and within group traits was found. Different correlations between observed traits were found. Simple correlation coefficients and their significance were different for different genotype types for which the correlation was found (monoecious parents, andromonoecious parents, monoecious hybrids)..