Endophytic Ability of Different Isolates of Entomopathogenic Fungi Beauveria bassiana (Balsamo) Vuillemin in Stem and Leaf Tissues of Maize (Zea mays L.)

Abstract

The present study was conducted to examine the ability of six promising indigenous isolates of Beauveria bassiana (NBAII-Bb-5a, 7, 14, 19, 23 and 45) as an endophyte in maize stem and leaf tissues. Maize seedlings (var. Nithyashree) were inoculated with conidial suspensions and were examined for endophytic establishment in leaf and stems at different intervals during 15-90 days after treatment. All six isolates showed colonization in stem and leaf tissues with varying abilities of colonization and persistence. The mean percent colonization ranged from 7.41 to 20.37 % in older stem tissues and 3.70 to 21.29 % in young stem tissues and in leaf, it ranged from 6.46 to 27.78 % in older leaf tissues and 11.11 to 26.85 % in young leaf tissues. Among six isolates tested, Bb-23 isolate recorded the maximum mean colonization in older stem (20.37 %), older leaf (27.78 %) and in young stem (21.29 %). Bb-5a isolate showed maximum mean colonization in young leaf tissues (26.85 %). Persistence of inoculated fungal isolates decreased with increase in age of the plant. No physical symptoms of damage were observed in any of the B. bassiana treated plants. No colonization of B. bassiana was observed in the untreated control maize plants. The results obtained in plating and PCR techniques were similar with regard to the confirmation of endophytic establishment of B. bassiana. This study indicated the possibility of using B. bassiana as an endophyte in maize for management of maize stem borer, Chilo partellus.

Endophytic establishment of Beauveria bassiana and Metarhizium anisopliae in maize plants and its effect against Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) larvae

“…1 Effectiveness of the commercial strains Beauveria bassiana Bb-18 and Metarhizium anisopliae Ma-30 in the control of the second instar of Spodoptera frugiperda larvae host plant part and the method used. Renuka et al (2016) observed that stems of Z. mays were also colonized by B. bassiana; however, the availability and persistence on the plant tissues varied according to their age (high persistence in young tissues). Despite several authors have demonstrated that B. bassiana as endophyte of maize, others have been revealed that after the inoculation of this EPF on maize seeds, no colonization of plant tissues was obtained (Tall and Meyling 2017).…”

Colonization of Beauveria bassiana (Balsamo) Vuillemin strains in maize (Zea mays L.) and their efficacy against stem borer Chilo partellus (Swinhoe)

“…In the present study, B. bassiana strains exhibited better tissue colonizing ability in mature/young stem and leaf tissues when they were applied as oil formulation through foliar application. In another study (Renuka et al, 2016) oil formulation spray of B. bassiana isolates exhibited better endophytic ability when compared to aqueous conidial suspension spray. This might be due to loss of viability, decreased conidial germination on leaf surfaces.…”

“…In our earlier studies through laboratory bioassay (Renuka et al, 2015;2016), six promising strains of B. bassiana 7,14,19,23 and 45) were identified against C. partellus and were established as endophytes in maize stem and leaf tissues by artificial inoculation through foliar sprays of conidial suspensions.…”

Endophytic Entomopathogenic Fungi: A Valuable Biological Control Tool against Plant Pests

“…sorghum FA [73,77] SD [77] tobacco FA [82] ST [82] RD [82] wheat FA [82,94] SD [96,97] ST [94] RD [82] soybean FA [82] corn FA [95] maize FA [74,84,98] SI [74] RD [82] ST [32] potato FA [99] coffee FA [76,100] SI [76] SD [76] tomato FA [81,101] SD [17,27,34,103] SI [104] RD [81] ST [103,104,107] grapevine FA [31,90] banana SI [108] RD [108] fava bean ST [56] common bean ST [16] SD [78] cotton ST [27,70] soybean RD [82] cassava SD [109] sweet pepper SD [57] rice FA [110] Table A1. Cont.…”