The saffron dormancy period begins after drying above-ground parts, including actual and apparent phases. The differentiating reproductive organs during apparent dormancy need to be induced under optimal temperature conditions, while saffron farms are free of vegetation after the drying phase. Covering the soil surface during the summer season may be advantageous to counter such a major constraint. The current study was conducted at the experimental station of the Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, from 2018-to 2019 and repeated from 2019-to 2020. A split-split plot arranged in a randomized complete block design with three replicates was used. Limited moisture of white bean (10 d irrigation as lower interval and 20 d irrigation as higher interval), glycine betaine foliar application (0 and 10 mM), and planting patterns (sole saffron, sole white bean, and saffron + white bean intercrop) were considered as the main plot, subplot, and sub-sub plot, respectively. Higher irrigation intervals resulted in increased soil temperatures, while glycine betaine had an inhibitory effect against heat stress. The Saffron flower number significantly improved after applying 10 mM glycine betaine. Furthermore, the maximum middle- (5–10 g) and large-sized (> 10 g) daughter corms and land equivalent ratio were recorded when 10 mM glycine betaine was applied in saffron + white bean intercrop. A similar response was also recorded in N and P concentration in the middle- and large-sized daughter corms. Considering the water restriction in arid and semi-arid areas, saffron-white bean intercropping, concurrent with 10 mM glycine betaine application, can play a pivotal role in regulating soil temperature and increasing land equivalent ratio.

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