Evaluation of bolting and flower characteristics in some Iranian spinach landraces

Spinach (Spinacia oleracea L.) is a leafy green, cool-season vegetable that is known for its nutritive value and is considered one of the most popular leafy vegetables in the world. It is believed to have originated from Iran and was transported to India and Asia and then later to the Mediterranean countries and Europe. Different cultivars areused for commercial cultivation of spinach in the world, but seeds of native spinach landraces around many parts of Iran is being used for cultivation. Spinach is a low-growing annual plant that grows as rosette plant and spinach plant bolts rapidly when day length and temperature increase. Morphological variation of Iranian spinach have been studied, but there is no information about reproductive growth and flowering habit of Iranian spinach landraces. This information may be useful to perform spinach breeding and seed production programs. In the present experiment, the bolting and flower characteristics of eighteen Iranian spinach landraces („Tabriz‟, „Arak‟, „Gorgan‟, „Qom‟, „Qoochan‟, „Birjand‟, „Koohbanan-Kerman‟, „Shiraz‟, „Shirvan‟, „Janat Abad‟-Qom, „Urmia‟, „Varamin-1‟, „Varamin-1‟, „Varamin- 1‟, „Qazvin‟, „Karaj‟, „Saleh Abad-Qom‟) were studied. A Korean spinach cultivar was used as a control. Twenty reproductive characters of all landraces evaluated according to standard descriptors. Results showed that Iranian spinach landraces had significant variability for reproductive parameters, including number of leaves before bolting, flower- stalk color and color intensity, flowering height and smoothness, male and female flower color, branching flower plant, compaction of the male and female inflorescence. All landraces presented variation in bolting time, full bloom and termination time of flowering and three landraces („Qazvin‟, „Qoochan‟ and „Arak‟) presented precocity. Plants of „Qazvin‟ and „Qom‟ and produced the lowest leaf before bolting (6 and 8 leaves, respectively). It was seen that some genotypes („Qazvin‟, „Urmia‟, „Tabriz‟ and „Shiraz‟) had more anthocyanin in male and female flower- stalk and flower- stalk of „Qazvin‟ contain the highest anthocyanin content. The color of flower-stalk was found to be a distinctive marker to assess the diversity among Iranian spinach landraces. „Janat Abad- Qom‟ was the most distinct landrace due to deep green color in the female and male flower. Plants of „Tabriz‟ had the highest flower-stalk (92 cm). Results of the present study may be useful to breeders to identify Iranian spinach landraces.

Keywords:

Spinach (Spinacia oleracea L.) , Reproductive Growth , Genetic Resources , Anthesis , Bolting , Flowering Date