Research On Dynamic Photosynthetic Characteristics Of Gladiolus And Nutrient Accumulation In Corm

Photosynthetic characteristic of gladiolus and nutrient accumulation dynamic of its new corm were studied with ECA-PB0402 photosynthetic analyzer and pocket PEA in Bashang Plateau with a cold climate surported by Zhangbei Experimental Station, Agricultural University of Hebei.1.The light compensation point was 174.8μmol photons/(m².s),the light saturation point was 2145μmol photons/(m².s)The optimum temperature was 25℃,the Pn decreased when the temperature be higher than 25℃,Fv/Fm decreased when the temperature be higher than 30℃.It showed that gladiolus was restrained when at high temperature,the inactivation of PSâ…¡reaction center.,the function of PSâ…¡descending.When the temperature was over 40℃,the chlorophyll fluorescence abduction curve of gladiolus presented amphibolously O-K-J-I-P five type.This wad accounted for over 40℃.The water cracking system of PSâ…¡of glaliolus and the start part of pre-acceptor of Q_A was restrained.And oxygen expanding compound(OEC)was injured.In addition,the relation of the dark respiration function and temperature was linearity and according to the higher of temperature it became augment.2.The leaves of gladiolus had distinctly Diurnal change law.In the abundance of water and fertilizer condition of sunny day on June and July Pn was single apex curve,and its had a little declined at noon.And also was that AQY,and Fv/Fm.Which was made out that at noon in the sunny day the centre of PSâ…¡losed the reversible activities and its function decreased who happened to light and temperature restained.In August Pn had the double apex curve,which had the noon-broken.3.Pn of the leaves was presented good disciplinary variety according to the season. The entironment of June and July such as illumination,temperature,air humidity and the like,was well adapted to the growth of gladiolus.In the phases the photosysthesis ability was in a higher level which is an important period of growth of upside parts of gladiolus. In August high temperature and strong lights made gadiolus low photosysthesis ability, which was showed temperature and light restraining.In the long sunlight of Bashang new corms stopped their growth and the minish of storeroom also made Pn decreased as while. In Sep With the Improvement of the circumstance the photosysthesis ability ascended at first and descended gradually with the senescence of the leaves. 4.In greenhouse Pn of leaves was single apex curve Diurnal and change of bearing period.Because of the weak light and high temperature in greenhouse was made the less photosynthetic production and higher plants,smaller diameter,fresh weight and net weight than the field,while the fresh and net weight had none of remarkerable difference.5.It was made the leaves of Pn changes daily with shading.20%-shading,30%-shading was assumed a double apex curve of Pn daily.While was 60%-shading the curve was sigle apex curve.And shading was not influence the Pn of that in season.60%-shading was increased the height while decreased the diameter,the fresh and net weight of the corms, the rate of cutting flowers.6.Sowtime was little influenced of the Pn of leaves in season.After May 5^ththe gladiolus was none of flowers in gear and the weight of new corms severely decreased which couldn't ripe.So the latest sowtime must before May 5^th.7.The plants of gladiolus was resumable in the frost of Sep in Bashang.It was different with the process in the field and simple shed.In the field the severest frost happened at 7:00 in the day,while the simple shed was in the second day.And the frozen harm was non-resumable with the inner structure harm of the cells and the chlorophyll fluorescence abduction curve almost disappeared,losed their photosynthetic ability.8.The new corms growed slowly at first and then quickly.Water contain decreased gradually with the ripeness degree.In the beginning time of florescence with the long light the weight of new corms decreased slightly.And it's the main period of accumulating net substance after florescence,which accumulated 74.3%fresh substance and 77.6%net.9.Cutting flowers made the bearing time longer and the ripeness degree of new corms decrease,while the flesh weight and net weight was higher than that of non- cutting flowers'.