Growth, phenology and chlorophyll fluorescence of habanero pepper (Capsicum chinense Jacq.) under water stress conditions

The irrigation methods offer a good alternative for increasing water use efficiency. The main purpose of this study was to identify the best irrigation level for Habanero pepper (Capsicum chinense Jacq.) plants based on available water capacity (AWC) of substrate. An experiment carried out with three irrigation levels (20, 40 and 60% of AWC) and five genotypes (H225, H241, H244, H226 and Jaguar). The irrigation level of 20% decreased the soil water potential to cause water stress in plants. At an irrigation level of 40%, average jaguar plant height (92 cm) and H241 (79 cm), genotypes were greater than under the other treatments. Average leaf area of H225, H241 and H244 plants was at least 48% greater than Jaguar plants. Average total dry matter of H241 and Jaguar plants, were 30 and 28% greater than H226 plants; and values of maximum photochemical quantum yield (Fv/Fm), relative electron transport rate and effective photochemical quantum yield of photosystem II were higher in H241, H244 and H226 plants; i.e. they are less probably due to photo inhibition damage. However, flowering time was earlier in plants with an irrigation level (IL) of 20% than plants with an IL of 40%, this was a consequence of stress due to water deficit. The 60% irrigation treatment caused flooding and all genotypes died before the inflorescence stage. These results suggest the enforcement of a suitable irrigation level based in available water capacity of substrate coupled with a vigorous genotype can encourage healthy plants and high water use efficiency