The Development of Lulo Plants (Solanum quitoense Lam. var. septentrionale) Characterized by BBCH and Landmark Phenological Scales

Abstract

ABSTRACT The landmark and the Biologische Bundesantalt, Bundessortenamt, and Chemische Industrie (BBCH) scales describe the phenology of lulo plants. The landmark scale comprises six main stages, 1.0 seed germination, 2.0 seedling growth, 3.0 early vegetative growth, 4.0 leaf development, 5.0 floral, and 6.0 fruit development. Seed gemination stages describe seed sowing, imbibition, and subsequent germination. Seedling growth stages include the emergence of hypocotyl hook, seedling growth, the development of cotyledons, and true leaves. During the early vegetative shoot stages, plants increase in height, pubescence turns dark, cotyledons abscise, and thorns become visible at the base of the leaf. Leaf development stages comprise the emergence of young, true leaves, and leaf expansion. During this period, leaf color changes from light green to mature dark green and ends with leaf senescence. Floral development stages include the emergence of the swollen generative buds, early floral-bud development, inflorescence enlargement, anthesis in hermaphrodite or male flowers, and floral parts decay and abscission. Fruit development stages include fruit developing below the petals, the light green tiny fruit enlarges forming the small, enlarged, intermediate, and light green fruit. Fruit turns dark green until reaching the mature dark orange color. The BBCH scale depicts eight principal stages such as seed germination, leaf development, formation of side shoots, inflorescence emergence, flowering, fruit development, fruit maturation, and senescence. The BBCH mesostages and secondary growth stages were described and coded according to the two- and three-digit-code system. The secondary stages were used as precise steps during development of the plants. Flower and fruit production occurred throughout the year. This research can be used to better understand the flowering and fruiting process and it can be applied to breeding and production programs.