Moreover, spores from submerged cultivation were able to colonize oilseed rape leaves via leaf application.
Polygalacturonases have been studied in tomato abscission zones [ 31], in oilseed rape and Arabidopsis leaf and flower abscission zones [ 32], while celluloses have been studied in cotton [ 33], citrus fruit [ 34] and red raspberry abscission zones [ 35].
Finally the virulence of the produced spores was checked in a bioassay with Plutella xylostella and their potential to colonize oilseed rape leaves via a leaf application was investigated.
To the best of our knowledge, this is the first report of fermentation of an endophytic B. bassiana strain in a low-cost culture medium to very high yields of TS, which are able to penetrate oilseed rape leaves via a leaf application.
Fig. 5 Amount of soluble hydrogen peroxide per gram of leaf tissue from oilseed rape treated with nutrient solution containing IONs and challenged with drought for 5 days (n = 16, p value = 0.004).
But some of the proteins present in leaf apoplast of oilseed rape or belonging to secreted proteins of Arabidopisis [this study, [ 28, 35]] were not found in xylem saps [ 2, 3].
The N-amino acid amounts were deduced by using an average value for molecular mass (110 g.mol−1) and the N ratio (7.86) obtained from previous studies in leaf samples of oilseed rape was used to determine the N-amino acid amounts.
The formulation was brushed onto the 9th secondary leaf tips of seven oilseed rape plants and afterwards, endophytic B. bassiana was detected in the tissue of the untreated leaf base by PCR and microscopy.
Among the identified proteins we confirmed the presence of chitinases, peroxidases, proteases, glucanases, germins, and some proteins involved in cell wall modifications in the leaf apoplast of healthy oilseed rape.
