RESUMEN
Phragmites australis (Poaceae) is a cosmopolitan reed grass, so far reported only in Eastern Region of Saudi Arabia. Our recent field exploration in the South West Region of Saudi Arabia resulted in documentation of this species in Gizan City (Jazan Region). The species is reported here as a first record in Jazan Region and an addition to Jazan flora. A note on distribution, ecology, and brief description of the plant is also provided.
RESUMEN
Work aimed at assessing status and introducing water conservation regimes for coffee production in southern Saudi Arabian highlands. Data on farm locations, altitudes, areas, practices, irrigation, tree density, and annual coffee production were analyzed. Field experiment using chlorophyll fluorescence and different irrigation regimes was conducted to examine effects of reducing irrigation frequency on photosynthesis. Results indicated that Coffea arabica L. is commonly grown at altitudes of 1300-1400â¯m. Plants grown at 4-6â¯Treesâ¯m-2 using 100â¯kgâ¯ha-1 mineral fertilizer produce an average of 3â¯tâ¯ha-1. High frequency 2-day-intervals irrigation regime practiced by farmers during the dry season presents ecological challenge to limited local artesian water resources. Changes in chlorophyll fluorescence under 14-day-intervals irrigation regime initiated water stress that markedly inhibited Photosystem II efficiency and quantum yield and increased non-photochemical energy dissipation. Applying a 7-day-intervals irrigation regime induced less inhibitory effects on Photosystem II. Results also indicated that shifting from 2-day-intervals irrigation regime to 7-day-intervals regime improves coffee agroecology and directs coffee production towards sustainability.