Influencia de un injerto en el perfil de ácidos grasos y algunas propiedades fisicoquímicas de la semilla y el aceite de semillas de sandía

This study aimed to investigate the effects of grafting on the fatty acid profile and some physicochemical properties of watermelon seed and seed oil. The ‘Crimson Tide’ cultivar was used as the scion while two wild watermelon (Citrullus lanatus var. citroides (A1 and A2)), one Lagenaria siceraria (A3) and one Cucurbita maxima Duchesne x Cucurbita moschata Duchesne (A4) were used as rootstocks. The use of rootstock significantly influenced the fatty acid profile and the physical parameters of seeds and seed oils. The highest linoleic acid ratio was found in the seed oil from A1 and A2, the oil from A3 had the highest oleic acid ratio. The results showed that the content and acid value in seed oils were improved, and that total phenolic compounds and antioxidant activity of both seed and oil were decreased by grafting. Wild rootstocks can be used in watermelon cultivation to obtain a watermelon seed which is rich in linoleic acid.El objetivo de este estudio fue investigar los efectos del injerto en el perfil de ácidos grasos y algunas propiedades fisicoquímicas de la semilla y el aceite de semillas de sandía. El cultivar ‘Crimson Tide’ se utilizó como vástago, mientras que dos sandías silvestres (Citrullus lanatus var. Citroides (A1 y A2)), una Lagenaria siceraria (A3) y una Cucurbita maxima Duchesne x Cucurbita moschata Duchesne (A4) se utilizaron como portainjertos. El uso de portainjertos influyó significativamente en el perfil de ácidos grasos y los parámetros físicos de semillas y aceites de semillas. La proporción de ácido linoleico más alta se encontró en el aceite de semillas de A1 y A2, el aceite de A3 tuvo la proporción de ácido oleico más alta. Los resultados mostraron que el contenido de aceite y el índice de acidez mejoró y los compuestos fenólicos totales y la actividad antioxidante tanto de la semilla como del aceite se redujeron mediante el injerto. Para obtener un aceite de semillas de sandía rico en ácido linoleico, se pueden utilizar portainjertos silvestres en el cultivo de sandía

The effects of anti-mitotic agents on dihaploidization and fertility in winter squash (Cucurbita maxima Duch.) and pumpkin (Cucurbita moschata Duch.) androgenic haploids

Double-haploidization (DH) is one of the favorable techniques to obtain 100% pure double haploid plants (DH’s) for generating the new F1 cultivars in a short time. The fecundity of this technique depends on the high quantity of haploids and also fertile DH’s. However, there are no comprehensive reports on the chromosome doubling and fertility (fruit and seed-set) of winter squash and pumpkin haploids, currently. Thus, to obtain high frequency and fertile DH’s, the efficiency of different anti-mitotic agents (colchicine, amiprophos methyl, trifluralin and oryzalin) was tested at various concentrations and exposure times for both in vitro and in vivo conditions. Haploid plantlets recovered from anther cultures of winter squash and pumpkin lines were used for DH program. The haploid plants were wholly immersed in aqueous solutions of antimitotic agents in vitro and apical parts of haploid plantlets were treated with anti-mitotic agents three times in vivo. Since some plants remained haploid, and the highest DH efficiency was obtained from multiple treatments of colchicine to shoot tips of haploid plants in the rate of 93.3%. In vivo multiple treatments of 1% colchicine for an hour was found to be the best doubling procedure for the recovery of high-frequency fertile DH’s in our winter squash and pumpkin breeding program

Obtention of haploid embryos and plants through irradiated pollen technique in squash (Cucurbita pepo L.)

The influence of gamma ray doses (25, 50, 75, 100, 200, 300 and 400 Gy) and genotypes (Eskenderany F1, Acceste F1, Sakiz, Urfa Yerli) on the induction of haploid embryos obtained by irradiated pollen technique was studied in squash (Cucurbita pepo L.). Different shapes and stages of embryos were derived from seeds extracted from fruits harvested 4-5 weeks after pollination. As a result of the present study, haploid embryos and haploid plants were obtained, with haploid production strongly influenced by gamma ray doses, embryo stages and genotypes. Gamma ray doses of 25 and 50 Gy gave the highest parthenogenetical response. All of the point shape, globular shape, arrow tips and stick-shaped embryos developed into haploid plants. However, only 53.8% of torpedo and 23.1% of heart-shaped embryos gave haploid plants. In contrast, cotyledon-shaped and amorphous-shaped embryos produced only diploid plantlets. The number of embryos per 100 seeds was the highest in 'Eskenderany F1' and 'Sakiz' genotypes. After in vitro culture, a total of 93 haploid plantlets were obtained

Evaluation of seed yield, oil and mineral contents inbred pumpkin lines (Cucurbita pepo L.) under water stress

Water stress is one of the main constraints which could limits crop productivity, especially in arid and semi-arid regions characterized limited water resources. This study was conducted to investigate the seed yield, oil and mineral contents of 44 lines and 4 commercial pumpkin varieties (2 local and 2 hybrids) in irrigated and drought stress conditions. The study was conceived as a randomized block design with three replications and carried out during the 2017 growing season. On average, the irrigated plots produced 161.27 kg da⁻¹ seed yield whereas it was 33.67 kg da⁻¹ in non-irrigated plots. The highest yield among the commercial pumpkin varieties was obtained from the G2 hybrid variety in the irrigated conditions. On the other hand, in the non-irrigated plots, higher seed yields were obtained from G9, G34, and G36 pure lines. Drought resulted in a remarkable decrease in the total oil content and significant increase in the amount of Ca and Zn in pumpkin seeds. These results clearly indicated that G9 line, which has the highest seed yield in both irrigated and drought conditions, can be utilized as a recommendable parental pumpkin line in future hybrid breeding efforts