Registration of ‘Boyero UNNE’ Bahiagrass

Abstract

‘Boyero UNNE’ (Reg. No. CV‐5, PI 676021) bahiagrass (Paspalum notatum Flüggé) was registered with the National Register of Plant Cultivars and the National Register of Property for Plant Cultivars, Ministry of Agriculture, Livestock Exploitations, and Fisheries of Argentina, Resolution no. 276 in August 2012 (Reg. No. 3213) and released by the National University of the Northeast (UNNE), Faculty of Agricultural Sciences (FCA), Corrientes, Argentina. Boyero UNNE is a tetraploid, highly apomictic F1 hybrid developed between an experimentally obtained female parent, reproducing sexually, and an apomictic, wild bahiagrass genotype. It is the first registered cultivar of a tetraploid apomictic P. notatum developed by breeding through a sexual × apomictic hybridization scheme, exploiting apomixis and plant selection in the F1 progeny. The new cultivar has a more upright growing habit than tetraploid bahiagrass cultivars currently in use or wild tetraploid biotypes. It can produce approximately 19% more forage dry matter than its apomictic male parent, largely exceeding (20–51%) the wild bahiagrass type currently found in natural pasturelands of northeastern Argentina, and it produced 4 to 26% more than the cultivar Argentine at three locations in Florida, USA.

Transference of natural diversity from the apomictic germplasm of Paspalum notatum to a sexual synthetic population

“…No. CV‐5, PI 676021) (Urbani et al, ). An interesting attempt to increase the available sexual tetraploid germplasm has been made by Quesenberry et al ().…”

How to Become an Apomixis Model: The Multifaceted Case of Paspalum

“…Heterosis for traits of interest, such as forage yield and cold tolerance, have been repeatedly reported in P. notatum [ 72 , 73 , 75 , 134 ] and for interspecific hybrids between P. plicatulum and P. guenoarum [ 70 , 135 ]. An apomictic hybrid of P. notatum identified as upright and fast-growing was recently released as a forage cultivar named Boyero UNNE, resulting from a collaborative research between the University of Florida and the National University of the North-East, Argentina [ 136 ].…”

“…This can be achieved by assessing phenotypic homogeneity in the progeny or by female gametophyte observations [ 74 , 75 ]. Moreover, random MMs are used in progeny tests, to determine the apomixis expressivity, and the genetic stability of an apomictic cultivar [ 136 ]. This is an important point to consider before going forward with the breeding process, because a relatively high expression of sexuality will reduce the stability of the new cultivar in a few years.…”

“…Superior apomictic hybrids usually need to go through a multiphase forage evaluation procedure [ 142 ]. The genetic homogeneity of the progeny coming from each selected line can be tested with random markers [ 136 ], to ensure the high expressivity of apomixis among the best lines. Phase 2 allows the selection of the best sexual genotypes that were crossed in phase 1, and these are polycrossed to generate an improved sexual population (phase 3 in Figure 7 ).…”

Reproductive Systems in Paspalum: Relevance for Germplasm Collection and Conservation, Breeding Techniques, and Adoption of Released Cultivars

“…This technique was developed by Young et al (1979) and recently modified by Zilli et al (2015); it requires plants at flowering stage and provides reliable information about expressivity of apomixis (Ortiz et al, 1997) and also is inexpensive, rapid, and straightforward (Zilli et al, 2018). Flow cytometry on seeds was used in P. notatum (Urbani et al, 2017), P. simplex (Brugnoli et al, 2014), P. malacophyllum (Hojsgaard et al, 2016), P. rufum (Delgado et al, 2014), and in inter-specific hybrids of the Plicatula group of Paspalum (Aguilera et al, 2015). This technique provides similar information to embryo sac observation, but determining expressivity of apomixis at seed stage, though giving a more accurate approximation to what is expected in the progeny, comes at a higher cost in comparison to embryo sac observations.…”