OBJECTIVESeed dormancy mechanisms, breaking dormancy and the optimal germinating conditions were studied to improve reproductive efficiency and quality standard of Pseudostellaria heterophylla.

METHODThe P. heterophylla seeds were stratified into wettish sand for 65 days under the temperature of -2-3 degrees C, embryo length and germination dynamic change of seeds were measured in prophase every other 10 days and in middle every other 5 days. The influences on seed germination and seedling growth under different temperatures, germination beds were investigated.

RESULTThe P. heterophylla seeds embryo morphology was unchanged in stratification. The seeds could not germinate at stratification within the first 35 days. The germination rate and germination energy of seeds increased with the stratification time after 35 days. Germination rate, germination energy, plant height and fresh weight under the 10 degrees C were significantly higher than those under other temperatures. Germination rate, germination energy, plant height, fresh weight and dry weight of plant in sand bed were higher than those of plant in other beds, and seed mildew rate and abnormal seedling proportion of plant in sand bed were less than those of plant in other beds.

CONCLUSIONThe dormancy of P. heterophylla seeds is mainly the physiological post-maturation. The optimal germination conditions of seeds is 10 degrees C the culture of sand. The dormancy was broke under -2-3 degrees C of wettish sand for 45-50 days in practice.

Caryophyllaceae ; growth & development ; Germination ; Light ; Plant Dormancy ; physiology ; Seeds ; physiology ; Temperature

OBJECTIVETo study the seeds dormancy release and physiological change of Thesium chinense.

METHODTo release dormancy, the seeds of T. chinense were treated with chemical reagent and stratification under 3-5 degrees C.

RESULTWhen washed with flowing water for 24 h, then soaked in 500 mg x L(-1) GA3 for 24 h, finally, treated with stratification method under 3-5 degrees C for 150 day, the split rate of T. chinense seeds reached 22%, crude fat decreased 50%, total sugar and dissolvability sugar increased 3-4 times, ABA decreased more than 90%, GA3 increased more than 5 times.

CONCLUSIONThe seeds dormancy of T. chinense can be released with the method of washing with flowing water for 24 h, then soaking in 500 mg x L(-1) GA3 for 24 h, finally, treated with stratification method under 3-5 degrees C for 150-180 day.

Abscisic Acid ; pharmacology ; Carbohydrates ; analysis ; Cold Temperature ; Fats ; analysis ; Germination ; physiology ; Gibberellins ; pharmacology ; Magnoliopsida ; drug effects ; physiology ; Plant Dormancy ; drug effects ; physiology ; Plant Growth Regulators ; pharmacology ; Plants, Medicinal ; drug effects ; physiology ; Seeds ; drug effects ; physiology ; Time Factors ; Water ; pharmacology

The germination rate and longevity of seeds of Gastrodia elata Blume have been observed for 48 weeks using Mycena osmundicola strain H-21, one of fungi stimulating seed germination. Storage condition of post-harvest seeds was observed in the different temperature ranges of -30degrees C, -5degrees C, 5degrees C and 30degrees C for 48 weeks. After storage period of 48 weeks, the germination rate of G. elata was 65.7% at 5degrees C and 71.6% at -5degrees C, respectively. Although the germination rate of G. elata was 77.3% for 11 weeks at 25degrees C, the germination rate had been decreased gradually to 49.3% at 13 weeks, 0.3% at 23 weeks and then 0% at 25 weeks. The germination rate was reached to the level of 10% for 2 weeks at -30degrees C and then decreased to 0%.
Fungi* ; Gastrodia* ; Germination* ; Longevity

OBJECTIVECurrent study was conducted to investigate the seed physiological characteristics of Tulipa edulis and improve germination rate.

METHODAnatomical characteristics was observed. Seed water absorption curve was tested by soaking method. Dynamic of embryo development and germination rate as well as germination index under different conditions were recorded. And the biological test of cabbage seed was used for detecting the germination inhibitors.

RESULTThe embryo rate of newly matured seeds was about 10%, and there was no obstacle of water absorption on testa of T. edulis. The optimum method for embryo development was exposure to 300 mg x L(-1) gibberellin solution for 24 hours, and stratification at 25 degrees C for 70 days followed by stratification at 5 degrees C for 40 days. The germintion rate and germination index of dormancy-broken seeds under the dark environment at 10 degrees C and 15 degrees C were significantly higher than those under other conditions. Additionally, there were some germination inhibitory substances in dry seeds.

CONCLUSIONThe seed of T. edulis can be classified as having complex morphophysiological dormancy, and the morphological embryo dormancy played a leading role. Warm and cold stratification resulted in a fast dormancy breaking effect, and a high germination rate more than 90% could be obtained under the optimum conditions.

Germination ; physiology ; Seeds ; physiology ; Tulipa ; physiology

OBJECTIVEThe aim of this study was to optimize the testing methods for seed quality, and to provide a basis for establishing seed testing rules and quality grading standard of Glycyrrhiza uralensis.

METHODReferring to the International Seed Testing Rules made by ISTA and Rules for agricultural seed testing (GB/T 3543-1995) issued by China, the seed quality of G. uralensis from different collection areas was measured.

RESULT AND CONCLUSIONThe seed testing methods for quality items of G. uralensis, including sampling, purity analysis, verification of genuineness, weight of 1 000 seeds, percentage germination, moisture content and seed viability of G. uralensis had been initially established.

Germination ; Glycyrrhiza uralensis ; chemistry ; physiology ; Seeds ; physiology

OBJECTIVETo optimize the testing methods for seed quality, and provide basis for establishing seed testing rules and seed quality standard of Oldenlandia diffusa.

METHODAccording to the related seed testing regulations, the seed quality of O. diffusa from different producing areas was measured.

RESULT AND CONCLUSIONThe testing methods for seed of O. diffusa was established, including sampling, purity analysis, weight per 1 000 seeds, seed moisture content, seed viability and percentage germination.

Germination ; Oldenlandia ; chemistry ; Seeds ; chemistry ; physiology

OBJECTIVETo analyze the genetic difference of biological characters on germplasm resources of Sophora alopecuroides.

METHODTwenty-three populations of S. alopecuroides from Ningxia, Gansu, Qinghai, Xinjiang and Inner Mongolian were used to analyze the seed size, 1 000-grain weight, and germination characteristics and so on.

RESULTIt showed that there were significant differences in seed size, 1 000-grain weight and the vitality of seeds. The biggest seed of S. alopecuroides was 4.7 mm x 3.5 mm, and the smallest was 3.8 mm x 2.9 mm, and the 1 000-grain weight was 15-26 g. Results of seeds vitality in 8 populations indicated that the highest vitality of seeds were No. 103 and No. 122. The germination index was 36.51 and 36.24 respectively, and the vitality index was 1 323.49 and 1 274.56. The coefficient of variation in seed traits exceeded 10% except the seed size.

CONCLUSIONThere are some differences and different heredity background in various S. alopecuroides germplasm resources.

Genetic Variation ; Germination ; Sophora ; classification ; genetics ; physiology

N-Methylhydrasteine hydroxylactam and 1-methoxyberberine chloride, both alkaloids, extracted from Corydalis longipes have been assayed for their activities against two powdery mildews. The spore germination of Erysiphe cichoracearum on detached leaf of balsam(Impatiens balsaminia) following pre- and post-inoculation treatments by their mixture has shown high efficacy against the pathogen at 100, 200 and 300 microg/ml. The mixture was also effective at both pre- and post-inoculation treatments at 500, 1000, 1500 microg/ml doses against E. pisi causing pea powdery mildew in pea(Pisum sativum) under field conditions. The significant efficacy of the mixture of two compounds against spore germination on detached leaves of balsam and also under field conditions in pea warrants its inclusion in trials against some other diseases under field conditions.
Alkaloids* ; Corydalis* ; Germination ; Peas* ; Plants* ; Spores

Leaf water potential of peanut subjected to drought stress is positively related to the oil content of peanut kernels. The aim of this study was to directly screen the high oil mutants of peanut and create the new peanut varieties using hydroxyproline as water potential regulator. In vitro mutagenesis was carried out with the embryonic leaflets of peanut variety Huayu 20 as explants and pingyangmycin as a mutagen added into the somatic embryo formation medium. The formed somatic embryos were successively transferred to somatic embryo germination and selection medium containing 6 mmol/L hydroxyproline (at -2.079 MPa water potential ) to induce regeneration and directionally screen high oil content mutants. After that, these plantlets were grafted and transplanted to the experimental field and 132 high oil mutants with oil content over 55% were obtained from the offspring of regenerated plants. Finally, among them, the oil contents of 27 lines were higher than 58% and of 2 lines were higher than 60%. A new peanut variety Yuhua 9 with high yield and oil content was bred from the regenerated plant progenies combining the pedigree breeding method. The yield was 14.0% higher than that of the control cultivar in the testing new peanut varieties of Liaoning province, and also it has passed the national registration of non-major crop varieties. Yuhua 9 with an oil content of 61.05%, which was 11.55 percentage points higher than that of the parent Huayu 20, was the peanut cultivar with the highest oil content in the world. The result showed that it was an effective way for directional breeding of high oil peanut varieties by means of the three-step technique including in vitro mutagenesis, directional screening by reducing water potential in medium and pedigree selection of regenerated plant progenies.
Arachis ; Droughts ; Germination ; Mutagenesis ; Plant Breeding

Trichoderma strains were evaluated under field conditions to assay their efficacy in suppressing Alternaria fruit rot disease and promoting chili plant growth. The experiment was conducted at the Botanical Garden, Rajshahi University, Bangladesh from July 2006 to March 2007. Application of Trichoderma harzianum IMI 392432 significantly (p = 0.05) suppressed the disease compared to Alternaria tenuis (T2) treatment and improved both growth and yield. The treatment T4 (T. harzianum IMI-392432 + A. tenuis) was most effective in reducing disease percentage (72.27%) compared to A. tenuis (T1) treatment. The highest seed germination rate (85.56%) and the highest growth and yield (12.5 g/plant) was also recorded in the same treatment (T4), followed by T5 (T. harzianum IMI-392433 000000 + A. tenuis), T6 (T. harzianum IMI-392434 +A. tenuis), T2 (T. virens IMI-392430 + A. tenuis), and T3 (T. pseudokoningii IMI-392431 +A. tenuis) treatment, while single treatment with A. tenuis significantly decreased these values.
Alternaria ; Bangladesh ; Fruit ; Germination ; Plants ; Seeds ; Trichoderma