Epinasty response on petiole angle of Capsicum frutescens L. in flooding stress

Abstract

Capsicum frutescens L. which belongs to Solanaceae family is one of the most important horticulture crops in the world that is very susceptible to water stresses including flooding stress. Flooding stress had been reported to affect tomato petiole epinasty, but in Capsicum frutescens L. there is no information yet. The aims of this study were to determine the effect of flooding on the petiole angle of Capsicum frutescens L. and to know the effect of abiotic factors such as temperature, and humidity in alteration of petiole angle. Three varieties of Capsicum frutescens L. with different characteristics, i.e. Cakra Hijau, Mhanu XR, and Sret were used in this study and grown in the greenhouse. Thirty days after transplanting, the treated plants were flooded:1-day flooding without periodic flooding (P0),  1 time periodic flooding (P1) and 2 times periodic flooding (P2). Control (C) plants were grown without flooding treatment. Petiole angle of all plants (control and treatment) was recorded at 3, 6, 18, and 24 hours during flooding period using transparent protractor. Data were analyzed statistically using Kruskal Wallis test. The result showed that petiole angle of plant that treated with flooding was significantly different with control. Plant that treated with periodic flooding (P1 and P2) showed larger changing of the degree of petiole angle of Capsicum frutescens L. compared to that without periodic flooding (P0). Flooding duration of 24-hours has increased the degree of petiole angle larger than 3, 6, 18 hours. The responses of each variety to the flooding treatment were different but not significantly based on Kruskal Wallis test. The petiole angle alteration of Capsicum frutescens L. also influenced by temperature and Relative Humidity (RH), in this study significant positive correlation with coefficient correlation 0,440 (p<0,05) between petiole angle and temperature and significant negative correlation between petiole angle and RH with coefficient correlation – 0,367 (p<0,05) using Spearman’s correlation test were obtained. However, in this study the petiole angle of Capsicum frutescens L. more influenced by flooding than temperature and humidity that indicates epinastic response of petiole.

Keyword: Capsicum frutescens L., epinasty, periodic flooding, variety