Study On The Occurrence Pattren Of Lilium Pumilum Flower Bud Trichome And Pollen Morphology Of 30 Lilies

Plant tirchome is of great significance to plant growth and defense,and L.pumilum has many excellent traits such as cold resistance and disease resistance that another lilies do not possess,and is an important genetic resource for lily breeding and variety improvement.Based on previous field investigations,this experiment used L.pumilum with flower buds without trichome and flower buds with dense trichome as materials,and recorded the phenotypic growth differences and the microstructure of trichome between the two during the development period of L.pumilum flower buds.Reverse breeding provides materials.The physiological characteristics of plant pollen are mainly regulated by genes,and are hardly affected by the external environment.It has a high degree of conservation and stability.The lily has a large pollen reserve,is easy to collect,and has obvious morphological characteristics.Therefore,different wild lily species are discussed from the perspective of palynology.The evolution and classification of lily varieties,combined with the results of traditional morphological taxonomy,will provide us with a more comprehensive reference in the classification of lily plants,resource development and germplasm innovation.The result test is as follows:1.In the early stage of trichome growth,the phenotypic characteristics of the two types of L.pumilum are not significantly different.As the trichome grows into a vigorous period,the plant height,stem thickness and flower bud length of L.pumilum are related to the related morphological indicators of L.pumilum.There are significant differences,and then when the trichome growth enters the end stage,the difference in the morphological indexes of the trichome of L.pumilum with trichome and L.pumilum without trichome gradually decreases,and there is no significant difference between the two.It shows that the growth changes of the trichome in different growth periods affect the changes of the morphological indicators of the plants themselves to a certain extent,and there is a certain positive correlation between them.Using 350 L.pumilum bulbs from the areas where the L.pumilum with trichome population is randomly planted,we estimate that the natural separation ratio of the L.pumilum with trichome plants in the field is about 57.99%.2.There are three occurrence positions of trichome and the growth status of different positions is different.The first type occurs in the trichome with the outer ring tepals of L.pumilum with trichome,which grows densely and vigorously;the second type occurs in the inner ring tepals and outer ring The tepals connect the trichome of the exposed parts,which are sparsely arranged and longer in length;the third type occurs in the trichome of the top leaf axils of both the L.pumilum with trichome and the L.pumilum without trichome,which are sparse and short and wither earlier;There are one species occur very rarely in the leaf axils of the stems of L.pumilum,with thick and thick trichome and short length.3.Scanning electron microscopy observed the trichome types of L.pumilum with trichome during the period of vigorous growth: Type I belongs to the apical cell size does not change,Type II belongss to the apical cell size is enlarged,all the trichome cells are rod-shaped,and no trichomes with branches and obvious secretions are found;Where the trichome is densely distributed,the trichome per unit area reaches 180～22.4.Clustering results based on pollen morphological characteristics: L.leichtlinii,L.pumilum and L.cernuum,L.duchartrei and L.davidii in the Sect.Sinomartagon gather together;L.sargentiae,L.leucanthum and L.sulphureum of the Sect.Leucolirion gather together with the L.tigrinum,L.dauricum and L.rosthornii in the Sect.Sinomartagon,and L.brownii in the Sect.Archelirion;The L.longiflorum of the Sect.Archelirion and the L.speciosum of the Sect.Sinomartagon gather together;Finally,the L.medeoloides of the Sect.Martagon and L.concolor of the Sect.Sinomartagon of the curled petal group Grouped separately into one category.most wild species can split according to the characteristics of Lilium,but some wild species are not included in the group or appear in other groups of Lilium.There are multiple differentiations in the curled petal group,and the composition is complicated.The classification position of Lily trichome is complicated,which needs further research to detemine.The pollen clustering results of 12 cultivars and 7 wild species are basically in line with the classification criteria of nine hybrid lines of Lily: the first group includes of L.pumilum,L.cernuum,L.davidii,L.leucanthum,and Asiatic hybrids’ ’Golden Passion’,’Buzzer’,’Performer’ and the‘Aladdin’ of the LA Hybrids;The second group includes the LA hybrids’ ’ Jessica’ and L.longiflorum;the third group includes all the Oriental hybrids ’Sunny Okinawa’,’Siberia’ and ’Muscadet’ and the OT hybrids ’Judith’,’Robert’ and ’Beijing moon’,the parent L.brownii of the Trumpet lilies and the parent L.speciosum of the Oriental hybrids,and the ’Bright Diamond’ of the LA hybrid line.It is concluded that pollen morphology is a relatively efficient and feasible method for classification of Lilium plants,but it is not comprehensive to classify Lilium only by pollen morphology.It needs to be combined with Cytology,Isozyme,RFl D,RAPD and other research results to jointly judge.5.Both the wild and cultivated varieties of lily have a single-groove germination hole and a single-row spine.The outer wall of the pollen has different sizes and shapes.The ridges are composed of particles with different shapes,sizes and arrangements.The shapes of the ridges are round,oval and rectangular.The mesh ridge particles of L.longiflorum are not obvious,with tubular membrane patterns.