SOIL WATER STRESS EFFECT WITH DIFFERENT IRRIGATION SCHEDULE DURING EMERGENCE AND SEEDLING STAGE IN Capsicum frutescens L. and Capsicum annuum L.

Abstract

The emergence and seedling development of a semi-domesticated hot pepper cultivar (C. frutescens), as a family-plot cultivated crop with attributes of water deficit tolerance adapted to the environmental conditions of arid zones, was studied and compared with a commercial variety of green pepper (C. annuum), one of the most cultivated crops in northern Mexico. An experimental design was carried out with both pepper species, under five treatments of water deficit. Results show a lower rate of emergence, a lower emergence percentage, and also a difference of 7 days to emerge for the semi-domesticated species as compared to the commercial species. Water deficit did not evidence effects on the development of the semi-domesticated hot pepper; its root length, height, and dry biomass production per plant were not influenced by the water deficit treatments. On the contrary, the commercial species C. annuum evidenced a reduction in height and dry biomass production under the most stressing treatment of water deficit, showing a higher vulnerability to water deficit. C. frutescens shows a slower emergence rate than C. annuum, the cultivated species, which implies an adaptation mechanism inherent to its semidomesticated condition to natural drought cycles, to which is commonly exposed. Water deficit treatments did no affected its growth, even under the extreme irrigation condition of 26 days without irrigation, equivalent to a water tension of -3.2 MPa. Results show a lower sensibility of C. frutescens to water scarcity, which suggests low water requirements for this species, representing in consequence a feasible option for arid and semiarid regions, where water deficit in soils is a typical condition of dominant ecosystems.