Interventi genetici ed agronomici per la costituzione e la valorizzazione di genotipi di carciofo ad alta resa in “seme” per la produzione di olio
Author(s)
Temperini, Andrea
Date Issued
March 18, 2011
Type
Doctoral Thesis
Abstract
Many plants accumulate in the seeds or fruits lipids as material for high-energy reserves. These fats such as oil or margarine are used for human consumption, and industrial transformation (soaps, oils, solvents, etc.). Only a few species (olive, sunflower, corn, canola, castor, etc..), in particular those subjected to intensive breeding, are currently used to produce oil. Taking into account the nutraceutical importance of globe artichoke oil reported in literature, a research program aiming at obtaining high yielding hybrids characterized by good organoleptic quality was carried out during the years 2008-2010. Experimental trials were conducted both in Italy and in United States, more precisely at the ARSIAL Experimental Center of Cerveteri (Roma, Italy), at the experimental farm of Tuscia University (Viterbo, Italy) and in the experimental fields of the Big Seed Heart Company (Brawley, CA, USA). The work involved research areas on (i) the pollination technique, (ii) the development of lines and F1 hybrids characterized by high seed yield, and finally by good qualiquantitative characteristics of the seed oil in the tested genotypes. The study on the pollination technique in globe artichoke showed that, both under open air and greenhouse conditions, it is necessary to relocate the bee hives near the crop and to treat inflorescences of male-sterile clones by a sugar solution (10% of sucrose) allowing to increase flower visits by insect pollinators. Pollination by brush or by head rubbing were valuable techniques, particularly when the female plant is located far from the male one, for example in another field or under another tent. It was also observed that, to obtain high seed yield, it is important to use varieties or hybrids with a high vigor, not only expressed as size of the plant but as pollen production and number of heads per plant. In this respect, the results obtained showed the importance to well knowthe inbreeding depression effect in globe artichoke, in order to develop uniform, stable and vigorous lines In addition, these results along with the high level of allogamy observed in globe artichoke (96%), demonstrate the propensity of this species at the cross-fertilization that is typical of the predominantly cross-pollinated species.
Seed production per head was not affected by the relationship between male-fertile and male-sterile plants inside the tent. This means that, , to maximize seed production of male-sterile plants inside the tent, it is necessary to maintain high ratios of Mf/ms because
the lowest ratio (1/10), used in the test, did not show productive levels statistically different from those obtained by higher ratios. This indicates that pollen production of a male-fertile plant is capable of ensuring complete fertilization of at least 10 male-sterile plants. Anyway, it is necessary to take into account that pollen production depends both on the genotype and the environment, as well as on their interaction. These results may give an indication on the relationhip between Mf and MS plants to be used inside the tent, although it should be noted that other genotypes might have different optimal ratios. The use of uniform and stable male-sterile plants , obtained by continuing the selection as well as by crossing and micropropagation work in progress for several years at Tuscia University and Big Heart Seed Company, lead to the realization of F1hybrids and lines, characterized by high seed yield and good uniformity. The productive level shown by these F1 hybrids was found to depend on the productivity of the parental lines used in the hybridizations. On the basis of the results obtained, we can say that globe artichoke, in comparison with cardoon, can be considered as crops usable for the seed oil production. In fact, the seeds of our lines and F1 hybrids contain about 25% of oil, which has characteristics similar to the oil extracted from sunflower seeds. In particular, the percentage of unsaturated fatty acids is very high and is represented by oleic and linoleic acids; there are also good amounts of tocopherols (vitamin E). The values of the parameters observed showed that the oil extracted from globe artichoke seeds has a good nutritive value so that it is interesting its use as food. Moreover considering that globe artichoke has been little studied in breeding programs aimed at improving oil quality and increasing seed and oil production it is possible to envisage, in the near future, the use of this species for the seed oil production. The best results obtained in the thesis work have reported in the cards on the morphological description (descriptors, CPVO) as well as on the oil content and quality of the lines selected.
Additional information
Dottorato di ricerca in Ortoflorofrutticoltura
File(s)![Thumbnail Image]()
Name
atemperini_tesid.pdf
Size
6.56 MB
Format
Adobe PDF
Checksum (MD5)
d9b19800618b264a24b1b0227d8255ae