Result of this study showed that application of drought stress have significant effect on plant height of Guinea and Napier grasses. Interaction between kind of grass and drought stress have significant effect too. Figure 1 showed plant height of Guinea decreased with increasing stress period treatment (DS2 to DS258). Treatment DS258 have lower plant height. However, decreasing
plant height of Guinea grass in DS25 follow D258 treatment. Napier grass showed decreased plant height in application D258 treatment. Napier grass have more tiller per pot than Guinea grass (Figure 2). Application DS2 treatment have tiller per pot did not significant difference with DS25 and DS258 treatment. Application drought stress treatment have same effect on tiller per pot of Guinea grass . Herbage mass of plant affect by all growth factors put on plant(Figure 3). Result of this study was showed that interaction of drought stress and kind of grasses have not effect on herbage mass. Furthermore, kind of grasses treatment showed effect to herbage mass, while drought stress treatment have significant effect to herbage mass. Decreasing Napier grass herbage mass have not significant difference with all treatment od period stress, while in Guinea grass herbage mass significance decreased by DS258 treatment.