Diversity among Coffea arabica populations in southwestern Saudi Arabia as revealed by their morphometric features

Coffee (Coffea arabica L.) is one of the most important agricultural commodities traded worldwide. The livelihoods of millions of households in Asia, Africa and America depend on it. The sustainability of the supply chain of this crop is increasingly under threat due to the impact of climate change in the main producing countries in the tropics and sub-tropics. The resilience of these agro-ecosystems will depend on the ability of breeders to develop new coffee varieties that can better adapt to changing environmental conditions. Therefore, studying the diversity of coffee populations in the Arabian Peninsula could reveal agronomically interesting genotypes that can be exploited in breeding programs. The objective of the study was to evaluate the diversity among coffee populations in southwestern Saudi Arabia using quantitative morphological, pomological and agronomic traits. The analysis of variance of the data showed differences among the accessions for most of the measured quantitative traits. The accessions varied in growth habit, canopy shape and cherry, bean and leaf dimensions. Cherry fresh mass ranged from 96.5 to 234.8 g in 100 cherries while 100-bean dry mass varied from 9.3 to 22.5 g. The hierarchical cluster analysis divided the accessions into four main groups. The study revealed considerable variability among the 61 accessions. Based on this investigation, accessions KSA-7R, KSA-8 and KSA-9R from Tallan valley, KSA20, KSA21 and KSA52 from Fayfa, KSA38 from Eddayar district, KSA10 and KSA60 from Assir region and KSA61 from Jebel Shada are recommended for further investigation for their promising agronomic traits