Effect Of Stem And Foliage Scab Disease On The Growth And Yield Of Vsp-1 Sweet Potato Variety

Ruben  M. Gapasin,; Josefina  G. Nayga,

Effect Of Stem And Foliage Scab Disease On The Growth And Yield Of Vsp-1 Sweet Potato Variety

Abstract:

Sweet potato plants inoculated with scab at 2 and 4 weeks after planting (WAP) were severely infected a shown by deformation of leaves and stunted plant growth. Scab infection also caused early death of main vines. However. this was not observed in plants inoculated at 6 and 8 WAP. Significant difference in di ease severity ratings, leaf area and number and weight of marketable roots were observed among the different treatment but not in fresh vine weight, and number and weight of non-marketable roots. Total root yield of plants inoculated with scab at 2 and 4 V AP was reduced relative to the control by 27 :8% and 24.5%, respectively. Eight-week old inoculated plants had a yield reduction of only 4.40Jo.

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