1887

n African Entomology - (Lepidoptera: Pyralidae) resistance in sugarcane ( sp.) : effects of spp., stalk rind, fibre and nitrogen content

Volume 22, Issue 4
  • ISSN : 1021-3589
USD

 

Abstract

Sugarcane cultivar resistance to is the best strategy to control the stalk borer. The present study aimed to establish the influence of stalk rind hardness, fibre and nitrogen content, and the effect species associated with infestation, on borer damage and performance in different sugarcane cultivars. In two glasshouse trials, larvae were inoculated into 7-month-old stalks of seven cultivars with different resistance ratings via wounds created in the rind. In one of the trials, -beneficial fungal strain pseudonygamai SC17 and antagonistic PNG40 were inoculated into the stalk of N41 and NCo376 three weeks before larval inoculation. Rind hardness and fibre content were higher in resistant cultivars and mature stalk parts, whilst nitrogen content was lower in these genotypes and in older tissues. However, survival, damage and growth indicators were not entirely consistent with known resistance ratings of cultivars, possibly due to the absence of the rind effect owing to mechanical wounding and differential effects of fibre and nitrogen in the cultivars. The absence of rind protection did not affect resistance in N29 and N33 upper internodes. infection was higher in the bottom of the stalk compared to the top in both N41 and NCo376. The least length bored was exhibited in the bottom internodes of NCo376 (3.3 cm) and N41 (1.7 cm) infected with PNG40, whilst SC17-colonized NCo376 stalks experienced the most damage (8.2 cm). The contribution of stalk rind hardness, fibre and nitrogen content to resistance in sugarcane may vary in different cultivars and stalk parts, whilst biochemical defences possibly play a larger role in some genotypes. Infection by species, especially in lower internodes, may have variable effects on resistance to the borer depending on the fungal strain present.

Loading full text...

Full text loading...

Loading

Article metrics loading...

/content/ento/22/4/EJC163594
2014-12-01
2016-12-10

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error