Demonstration of interspecific crosses between Nicotiana benthamiana and Nicotiana tabacum for intragenesis and the transient production of valuable small molecules and proteins

Intragenesis is classified as New Plant Breeding Techniques and agroinfiltration provides a simple, rapid and reproducible technique for transient gene expression. Sexual compatibility is a perquisite for the use of interspecies genetic components. In the present study, genetic crosses between Nicotiana benthamiana and N. tabacum have been achieved and viable progeny obtained. Resulting F₁ progeny were phenotyped and classification into three groups was observed. These phenotypes included N. benthamiana Lab-like phenotypes termed "BEN", representing 64 % of the progeny, while 8 % had observable N. tabacum phenotypes termed "TAB". Finally, 28 % represented a hybrid phenotype "HYB". Male sterility was present in group TAB and HYB. In order to assess the amenability of the progeny to agroinfiltration and to evaluate the potential of the new chassis with increased biomass and growth properties, the transient production of ketocarotenoids was performed. The progeny with BEN phenotypes showed increased ketocarotenoid production (∼1330 μg/g DW) compared to the control (∼550 μg/g DW). However, the increased leaf size found in the TAB and HYB progeny yielded greater ketocarotenoid levels per leaf (∼800 and ∼700 μg/g DW), when compared to the traditional N. benthamiana Lab accession. Further progeny of BEN and clonally propagated HYB were tested, but the beneficial traits for transient expression could only be attributed to the F₁ progeny cultivated from seed.