| The rust is one of the most important diseases in plants. Gymnosporangium asiaticum and G. yamadae are the pathogens of rusts in pear, apple, Chaenomeles sinensis, Chaenouzeles speciosa, Mains halliana and Cupresssceae plants and cause serious loss in these plants. The rust of Aecidium fraxinibuangeanae causes a severe white wax yield reduction in the important white wax production areas, like Leshan, in China. Rusts are severe diseases in many important medicinal and valuable wild plants in China, such as Aecidium schisandrae, A. sambuci, A. elaeagni-umbellatae, A. elaegni,A. asterum and so on.Tuberculina is an important hyperparasite of rusts in nature. Controlling plant rust diseases by hyperparasite is one of the most important biological control. Plants - Rusts - Hyperparasites composed a special " food chain " - " parasite chain " . Studies on biocontrol with hyperparasites are great theoretical and practical significance and will create a new field of study in China.This study is for the first time home and abroad to study the 6 species of Tuberculina, including Tuberculina pyrus on G. asiaticum and G. yamadae, T.fraxinis on A. fraxinibuangeanae, T. schisandrae on A. schisandrae, T. elaeagni on A. elaeagni-umbellatae and A. elaegni, T. sambuci on A. sambuci and T. persicina on A. asterum. Important research results and big progress have been achieved. The following are the main innovative research contents and the main conclusions. 1. Identification of the rust pathogen parasited by the hyperparasite (Tuberculina)Eight rust pathogens parasited by the hyperparasite (Tuberculina) were collected from Sichuan province and Chongqing city and identified. A. fraxinibungeanae parasited on Franxinus chinensis var. rhynchophylla, A. schisandrae parasited on Schisandra sphenanthera and A. asterum parasited on Aster albescens are newrecords of rust host in China .2. The distribution, habitat, hyperparasitism and morphological characteristics of the sporocarp structure2.1 The distribution and habitat of hyperparasite (Tuberculina spp.)The distribution of Tuberculina was investigated in eighteen cities and counties in Sichuan province and Chongqing city. The results showed that T. pyrus , T.fraxinis, T. schisandrae, T. elaeagni, T. sambuci and T. persicina were distributed in nine cities and counties in Sichuan province and Chongqing city including Emei shan city, Baoxing county , Ya'an city , Tianquan county, Pingwu county, Langzhong city , Guang'an city ,Wan county and Yunyang county. T. pyrus was distributed in eight of these cities and counties (excluding Tianquan county). These indicated the wide distribution and the abundant species of the hyperparasite (Tuberculina).The habitats of Tuberculina belong to the sub-tropic and wet quarter breeze weather. The habitats of Tuberculina were distributed from Yunyang county, Chongqing (with an elevation of 330 m, the highest temperature reaches over 40癈 in summer) to Baoxing (Qiaoqi) , Sichuan (with an elevation of 2 050 m , the lowest temperature reaches -10癈 in winter). It showed that the hyperparasite possessed a wide ecological adaptability.2.2 The hyperparasitism of Tuberculina and the morphological characteristics of the sporocarp structureThe common characteristics of the hyperparasitism of Tuberculina are: the hyperparasite appeared on both sides of the leaf with spots. And the hyperparasite on the lower leaf surface could control the rust. Early in the hyperparasitism, pale brown blisters could be visualized on the epiphyllous rust lesion. The blisters enlarged gradually , and their epidermis broke , giving off pale brown spores (conidia) . No capillary aecidia protruded on lower leaf surface. Later T. fraxinis, T. pyrus ( from Baoxing, Yaoji) and T. elaeagni produced the sclerotia on the place hyperparasitizd.The morphological characteristics of the sporocarp structure are: the sporodochia of hyperparasite grew along the surface. The conidiophores were fence-like, compact, colorless, stick-shaped ,with no branches ,They were wider at...
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