Breeding of a new mulberry [Morus] cultivar, Senshin

A new mulberry cultivar, Senshin, was bred at the National Institute of Sericultural and Entomological Science. It was selected from seedlings obtained by crossing the mother, Kyu 68-52, and father Oshimaso. Its resistance to dwarf disease had been studied at three experiment stations, in Tottori, Tokushima, Kagoshima Prefectures, for 5 years since 1988. Local adaptability has been tested at two experiment stations, in Gifu and Miyazaki Prefectures, for 4 years since 1994. Senshin was found to be superior to control cultivars in the resistance to dwarf disease and shoot cold injury. It was registered as Mulberry Nourin No. 19 and named Senshin by the Ministry of Agriculture, Forestry and Fisheries of Japan in August 1998. Senshin has the following characteristics: 1. It is a diploid cultivar belonging to Morus latifolia ROIRET. 2. Its form is characterized by moderate expansion resulting in tolerance to lodging. 3. Its medium shoots are long and fewer than those of Hayatesakari. The shoots are greenish brown and slightly zigzag. The internodal distance is somewhat short. 4. senshin has unloved thick, somewhat large, smooth, glossy leaves in spring to late autumn. The leaves are dark green and hardening in late autumn is nearly the same as that of Hayatesakari. The phyllotaxy is 2/5. 5. The sexual expression is predominantly pistillate, but with less sorosis. 6. The sprouting time in spring occurs a few days earlier than in the case of Hayatesakari. The young shoots grow vigorously and uniformly after sprouting. Resprouting after intermediate pruning in summer and autumn is vigorous. 7. Senshin has the same leaf yield and quality as Hayatesakari. 8. Senshin is highly resistant to dwarf disease and bacterial blight, but the resistance to powdery mildew is lower than that of Hayatesakari. Shoot tip cold injury is less pronounced than in Hayatesakari. Overall, Senshin can be easily cultivated in warm, open areas from the southern to eastern parts of Japan and is very adaptable to densely planted cultivation and mechanical harvesting in summer and spring pruning. Senshin is thus suitable for multiple silkworm rearing