Improvement of wheat by cytoplasmic breeding
Cytoplasm substitutions of the wheat cytoplasm by alien cytoplasms of wild and
primitive wheat relatives were carried out in Israeli wheat. An alloplasmic wheat line which contained the cytoplasm of the wild Aegilops variabilis from Israel was found to have significant superiority in yield when compared to the euplasmic cultivar. Furthermore this new wheat cultivar "Barnir" was found to outyield in dry as well as in irrigated wheat areas and to excel in protein stability in medium as well as in high levels of yield performance. It has excellent gluten index and high tolerance to the sunn pest - Eurygaster integriceps.
Improvement of grain protein content in wheat
Donors of high grain protein content from wild wheat species as well as from high protein wheat cultivars from different geographical regions of the world are hybridized with Israeli wheats. The various hybrids are subject to double haploid production. The new wheat breeding lines are tested for their agronomic performance in parallel to the selection for high grain protein content. First lines to be developed were found to surpass the best Israeli wheat by 2-3 percent of protein content.
Genetic improvement of baking quality in wheat via cell engineering
The lB/lRS wheat-rye translocation line is superagronomic wheat which is defected in very poor baking quality. The use of inductive somaclonal variation was attempted to develop new electrophoretic profiles of wheat storage proteins in this translocated line. A few lines were developed with in vltro variation in both gliadins as well as in glutenines. These changes includes an appearance of new proteins and also an elimination of existing ones. A selection of one out of these lines lead to the development of a super agromic wheat with exceptionally high baking quality which is equalizing to that of the Australian prime hard spring wheat. This line turned to be cv. "Ruta" which was adopted by leading companies in the milling and baking in dustries.
Screening and use of wild wheat relatives as donors for resistance to 'take-all' disease
Three hundred and fifty accessions of Triticum dicoccoides and 30 accessions of Aegilops speltoides, Ae. Variabilis, Ae. Squarrosa and Ae. Longissima were screened for resistance to 'take-all' (Gaeumannomyces graminis var. tritici). One accession of Ae. squarrosa, the fonor of the D genome of bread wheat, was found to be resistant. The resistance from this genotype is currently being transferred to wheat by hybridization via T. durum (genome formula AABB) followed by chromosome doubling to produce amphiploid (genome formula AABBDD). The synthetic wheat which was produced was found to retain the resistance to the fungal pathogen. Hybridization between the resistant amphiplid and commercial susceptible cultivars of bread wheat is currently being carried out.
Transfer of leaf rust resistance from Aegilops speltoides to bread wheat
Leaf rust caused by Puccinia triticina is one of the major diseases of wheat. Transfer of genes for resistance to this disease is of special importance in the effort to control this pathogen world-wide. Selections in the wild species Aegilops speltoides indigenous to Israel were found to have an exceptionally wide range of resistance to leaf rust (all the leaf rust races from countries from five world continents). This species is known also to have the ability to suppress the activity of the diploidizing mechanism in wheat, which reduces or eliminates homologous intergenomic transfers.
Ae. speltoides is, therefore, used as a genetic resistance source and inducer for the homologous transfer. A new bread wheat cultivar cv. Benedictus-16 has been already released from this program. It excels in yield performance and in high quality in the Bet-Shean valley and Lachish region.
Transfer to wheat of stripe rust resistance - Yr 15 gene from the Israeli Triticim dicoccoides
Stripe rust (yellow rust) caused by Puccinia striifonnis is one of the most devastating diseases of wheat thoughout the world. The disease has developed in the last decade new virulent races for which the prevalent resistance genes have become ineffective. Against that the resistance Yr-15 gene from the Israeli T. dicoccoides was found resistant to 20 stripe rust races from six countries and to all Israeli races of the pathogen. The stripe rust resistance is being transferred to Israeli wheat for the production of new resistant super agronomic wheat cultivars. The new commercial wheat cultivar Miss Po has already been released from this program.
Transfer and incorporation of alien genetic resistance to the cereal cyst nematode from wild wheat relatives
Cereal cyst nematodes (CCN), especially the species Heterodera avenae, are common and cause severe damage to the wheat crop in many countries all over the world. In Israel, the nematode has been a prominent pest of wheat since the late 1960's and early 1970's. Most of the centers of infestation were found in the northern Negev and the coastal plain. In a preliminary study, wild collections of Triticum dicoccoides, Aegilops squarrou. Ae. longissima and Ae. variabilis were surveyed for resistance to H. avenue. Four genotypes of Ae. variabilis growing naturally in areas infested with CCN were found to be resistant. Resistance was also found in three genotypes of T. dicoccoides and one genotype of Ae. squarrosa. These genotypes were resistant also to H. latipons, another cyst nematode species occurring in Israel. A program of hybridization between the resistant donors T, dicoccoides and Ae. squarrosa and bread wheat has already led to development of an Israeli wheat with enhancement of four fold tolerance to CCN compared to a current commercial wheat used in Israel.
Development of novel cereals as forage crops for hay and silage production
Bread and Durum wheats exhibit limited variability in forage characters in both protein content (9-10%) as well as in digestibility (64-68%). This limitation stems from the fact that the varieties of these species had been primarily bred as bread and pasta wheats and their forage quality characteristics were examined, if at all, during the final steps of the breeding process. Therefore a research program is conducted where high quality of feeding characters are the primary targets to be improved. The desirable characteristics for forage quality of high digestibility and high protein content are transferred into wheat from the gene pool of the wild wheat relatives. The new commercial forage wheat cv. "Miss Po" (line 37) was released successfully from this program.
Development of durum wheat with high pasta quality adapted to Mediterranean agro-ecological scenario
The relative limited world area which is ecologically suitable for Durum wheat cropping includes Israel within the Mediterranean basin. The increasing world demand for Durum wheat in the global grain trade calls for production increase of this grain wherever this cereal is adapted. Therefore a research effort is devoted to develop in Israel durum wheat of high pasta quality, resistant to the local biotic stresses and avoidable of the abiotic ones in semi arid area. The incorporation of leaf and yellow rust resistances from Israeli wild wheat relatives into American ellite desert durum wheats has already led to the production of the first desirable Israeli durum wheat cultivars: cv. Gvati, cv. Eliav and cv. Uzan. The new durum cultivars excel in high pasta quality and good yielding performance.