Abstract:
Potato productivity in Indonesia is relatively low, this could be due to seed quality,
climate, agriculture, and lack of knowledge about pests and disease. Synthetic
pesticides are a common choice for dealing with pests and diseases, but their excessive
use can be dangerous to humans health and the environment. An alternative to
minimizing the negative effects of using synthetic pesticides is to use several potential
plant extracts as biopesticide such as Nicotiana tabacum (tobacco), Morinda citrifolia
(noni), Cymbopogon citratus (lemon grass), Dioscorea hispida (gadung tuber), Piper
betle (betel) and Capsicum annum (chilli). The purpose of this study was to examine the
potential of six types of plant extracts as biopesticide for potato plants. Sample were
extracted by maceration method, and phytochemical screening was carried out by
GC-MS, then antimicrobial activity testing using well difusion and MIC by HTS
methods, against bacteria Ralstonia solanacearum, Xanthomonas citri, potato tuber
isolate and potato leaves isolate. Field tests were carried out on potato plant in Batur
village, Banjarnegara district, Dieng plateau, Central Java. Noni extract produced the
best antibacterial activity in the four types of bacteria with consecutive minimum
inhibitory concentrations, R. solanacearum 6.25 %; X. citri 12.50 %; Potato tubers
Isolate (I.K) 6.25 %; and Potato Leaves Isolates (I.D) 12.50 %. Phytochemical screening
result showed the presence of several compounds such as alkaloid, tannin, flavonoid,
steroid, and saponin. Potato plants that are treated with a mixture of all extracts get the
highest yield of 15,99 tons/Ha or 10 % higher than the yield treated by syntetic
pesticides 14,49 tons/Ha