Chemical control of spike disease of Sandal.
In experiments at Bangalore, S. India, on ca. 20-year-old Santalum album affected by spike disease in the forest and on 3-year-old potted S. album seedlings artificially infected by bud-grafting, three tetracycline compounds were applied to the trees either by spraying with an aqueous solution or by 'girdling', i.e. applying the compound to the stem as a paste after removing a portion of bark, the wound being sealed after application. The compounds were (a) demethylchlortetracycline hydrochloride, (b) tetracycline hydrochloride and (c) Benlate. When sprayed on, (b) and (c) were ineffective, but (a) apparently prevented any further increase in severity of the disease. When applied by 'girdling', (b) prevented further increase in disease severity, (c) checked the disease and resulted in signs of recovery of spiked shoots after ca. 5 months, and (a) arrested the disease and led to complete recovery of spiked shoots after ca. 60 days. The results are briefly discussed in relation to the recent attribution of spike disease to mycoplasma-like bodies [cf. FA 31, 4821].