Somatic embryogenesis and plant regeneration were successfully established on Nitsch and Nitsch (NN) medium from immature zygotic embryos of six genotypes of grapevine (Vitis vinifera). The optimum hormone combinations were 1.0 mg dm⁻³ 2,4-dichlorophenoxyacetic acid (2,4-D) for callus induction and 1.0 mg dm⁻³ α-naphthalene acetic acid (NAA) + 0.5 mg dm⁻³ 6-benzyladenine (BA) for embryos production and 0.03 mg dm⁻³ NAA + 0.5 mg dm⁻³ BA for embryos conversion and plant regeneration. The frequency of somatic embryogenesis varied from 10.5 to 37.5 % among six genotypes and 15.5–42.1 % of somatic embryos converted into normal plantlets. The analysis of DNA content determined by flow cytometry and chromosome counting of the regenerated plantlets clearly indicated that no ploidy changes were induced during somatic embryogenesis and plant regeneration, the nuclear DNA content and ploidy levels of the regenerated plants were stable and homogeneous to those of the donor plants. RAPD markers were also used to evaluate the genetic fidelity of plants regenerated from somatic embryos. All RAPD profiles from regenerated plants were monomorphic and similar to those of the field grown donor plants. We conclude that somaclonal variation is almost absent in our grapevine plant regeneration system.

The pea (Pisum sativum L.) is an excellent protein source for livestock and human nutrition. However, its growth is hampered by several factors including powdery mildew (Erysiphe pisi DC) and lodging in irrigation areas. These limitations may be solved through combining a Canada powdery mildew-resistant pea (Mp1807) with green cotyledon cultivar (Graf) by means of sexual hybridization. A bred semi-leafless pea, cultivar Longwan No. 6, was selected and evaluated in multiple ecological zones to investigate and evaluate high-yield, adaptability, and resistance to root rot (Aphanomyces euteiches Drechs. f. sp. pisi) and powdery mildew from 2012 to 2014. The results revealed that Longwan No. 6 was characterized by lodging resistance and moderate powdery mildew resistance. The average grain yield of Longwan No. 6 is 2855.3 kg/hm² in spring sowing and is increased by 18.4% compared to the control cultivar (Longwan No. 1). The average grain yield of Longwan No. 6 is 2349.9 kg/hm² in winter sowing and is increased by 12.8% when compared to the control cultivar. The results indicated that Longwan No. 6 has a greater potential to increase yield and wide adaptability. Adopting the Longwan No. 6 pea cultivar contributes to improvements in pea production in irrigation areas.

Fusarium wilt (FW), caused by Fusarium oxysporum f. sp. pisi (Fop), has always been an important disease affecting pea production and causing severe yield losses in most pea-growing areas worldwide. Growing resistant pea cultivars is the most economical and effective method for controlling the disease. In this study, firstly, 21 Fusarium oxysporum isolates were identified as races 1 and 5 of Fop based on morphological and molecular characteristics, and the disease reactions of seven pea differential cultivars. Then, a detailed resistance evaluation strategy was established and validated by a death rate score, disease index, and percentage of leaves showing symptoms for each individual plant. Finally, a 1311 pea germplasm collection including 740 accessions from China and 571 accessions aboard or unknown sources was evaluated for resistance to a representative isolate PF22b of Fop race 5, and the results showed that 28 accessions and 164 accessions were highly resistant (HR) and resistant (R), respectively. Among these resistance accessions, 13 HR and 44 R accessions were collected from 19 provinces in China, most of which came from Sichuan, Tibet, and Gansu Provinces. The 15 HR and 120 R accessions were collected in 10 countries outside China or unknown sources, the majority of which came from the United States, Australia, and Russia. The findings would provide important information for using resistance pea cultivars to control Fusarium wilt. Incorporating these resistance accessions into breeding programs will contribute to improving the Fop resistance of pea cultivars.