Relative susceptibility of some new promising sugarcane varieties to the pink borer, Sesamia cretica lederer and the purple- lined borer, Chilo agamemnon blezynski [electronic resource].

Includes references.

Six new promising sugar cane varieties were used to evaluate their relative susceptibility to shoot borer pink borer (PB), S. cretica and stalk borer the purple lined borer (PLB), C. agamemnon in both plant cane and 151 ratoon. All the promising varieties except G 95- 19 and G 95-21 were relatively highly tolerant to PB recording less dead hearts % than GT 54-9 (the major commercial variety). The plant cane was more sensitive to shoot borer than 151 ratoon. The sensitivity of the tested cane varieties differed significantly against PLB attack measured as bored stalk and bored joints percentage. Nothing of the tested varieties is immune to PLB infestation, meantime, all the new varieties showed relative higher degree of tolerant to stalk borer attack except G 95- I 9 than the commercial variety GT 54-9. The 1st ratoon was more susceptible to stalk borer attack than the plant cane. When the sensitivity was measured as girdled stalks percentage , the 151 ratoon was more sensitive than plant cane. Girdled stalks percentage positively but insignificantly correlated with borer stalks %, while, it correlated positively but significantly with bored joints %. Breakage stalks percentage as a measurement of the sensitivity reveal that, GT 54-9 and G 95-19 were the most susceptible varieties which exhibited the highest breakage stalks %, while, the other new promising varieties were relatively more tolerant. No. of holes/stalk, No. of holes/joint and No. of holes/infested joint significantly differed amongst the used varieties in both plant cane and 151 ratoon. Varieties could be classified according to its susceptibility as follows: high susceptible G 95-19, moderate susceptible GT 54-9, G 95-21, F161 and PH8013 and low susceptible G 84-47 and G 85-37.

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