Plant Pathogens at Work: Progress and Possibilities for Weed Biocontrol Classical versus Bioherbicidal Approach

Fig. 3. Biological control of Hamakua ‘Pa-makani,’ Ageratina riparia, with Entyloma compositarum, the white smut fungus introduced from Jamaica in 1974. (A) Nonseptate, hyaline, slender, arcuate conidia (30-40 x 3-3.5 μm) ofE. compositarum. Scale bar = 12 μm. (B) Abaxial surface of a diseased ‘Pa-makani’ leaf showing the characteristic white sporodochia, containing masses of spores of E. compositarum. (C) Infestation of A. riparia at 900 m elevation at Palani ranch, North Kona, Hawaii, before inoculations in December 1975. (D) Striking biological control of the ‘Pa-makani’ weed at Palani ranch, a site at 900 m elevation, 8 years after inoculation with the biocontrol fungus. (E-H) Biological control of banana poka Passiflora tarminiana with Septoria passiflorae introduced from Ipiales, Colombia in 1993. (E) Filiform, multiseptate, hyaline conidia of S. passiflorae (35-52 × 1.5-2 µm). Scale bar = 24 lm. (F) Symptoms of septoria leaf spot on banana poka leaves 30 days after inoculations with ‘lei inoculum.’ Notice necrotic dry leaves, remains of the original lei that was placed below the symptomatic leaves. (G) Piha-road bordering the US Department of the Interior-Fish and Wildlife Preserve Photopoint No. 2, 1850 m elevation, before the 1997 inoculation with S. passiflorae. Notice the banana poka vine climbing to the top of the koa forest. (H) Photopoint No. 2 showing 99% banana poka biomass reduction 6 years after inoculation. Reprinted from Biological Control, Volume 33, Issue 1, Eduardo E. Trujillo, History and success of plant pathogens for biological control of introduced weeds in Hawaii, pp. 113-122, Figure 2, 2005, with permission from Elsevier. Use of (G) and (H) by permission of the American Phytopathological Society. Reprinted from Biological Control, Volume 33, Issue 1, Eduardo E. Trujillo, History and success of plant pathogens for biological control of introduced weeds in Hawaii, pp. 113-122, Figure 2, 2005, with permission from Elsevier.



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Plant Pathogens at Work: Progress and Possibilities for Weed Biocontrol Classical versus Bioherbicidal Approach