Abstract:Candidate core collections of common wheat ( Triticum aestivum L. ) were established based on the geographical regions, ecotypes, 21 agronomic and botanic characters of basic collections (entire). The modern varieties were divided into 10 regions, the landrace into 28 sub-regions. In each region or sub-regions, numbers of entries were decided based on the square root of the basic collections with minor adjustment according to the genetic diversity and genetic richness indexes. Varieties or lines having made great contribution in the national wheat breeding and production are priority entries in sampling. The candidate core collections were established after all entries were re-planted and checked in the field. In the candidate core collections, there are 3283 landraces, and 1684 modern varieties, which takes 28.18% and 14.9% of the basic collections respectively. We are going to concentrate the candidate core collections to 10% of the basic collection by molecular markers. They will be the core collections of Chinese wheat germplasm. Statistics showed that there was no significant difference on variation between the candidate core collection and the basic collections except the awn and glumes. The corner mountainous region between the Southern Shaanxi and the Western Hubai, valley along Fenghe and Wei-he are the genetic diversity center of Chinese wheat landrace. In the modern varieties, Southwestern winter wheat region and Huang-huai winter wheat region have the highest genetic diversity.
Abstract:Core collection represents a maximum of the genetic diversity of the whole collection with a minimum of accessions and a minimum of redundancy. In order to test sampling of core collection, the study chose two groups at random among the core collection in Huanghuai summer sowing soybean, with 20 and 14 accessions , respectively; and selected 6 and 5 accessions respectively among the two groups of the reserve collection in Huanghuai summer sowing soybean, torally 45 materials. The study made use of 14 agronomic characters and 20 pairs of SSR primers. The core collection and the reserve collection were clustered together. The two groups in the core collection had 129 and 136 alleles, and the two groups in reserve collection had 76 and 71 alleles. The core collection add up to 86.00% and 86.62% of the diversity of the whole collection. The result indicates that the core collection include genetic diversity of the reserve collection at 70% level. The study provides the proof at molecular level for the evaluation of the availability of the core collection in soybean.
Abstract:Genetic variation, correlation, partial correlation and path coefficient of sensory quality traits of vegetable soybeans were analyzed based on 154 cultivars sampled from the major vegetable soybean producing areas. The results were as follows:The variation of the comprehensive sensory quality value,six first class sensory traits and five secondary sensory traits were all abundant enough; the variation of the first class sensory quality value was less than that of the secondary sensory traits; the genotypic coefficients of variation, heritability value, and selection potential were relatively large for 100-pod fresh weight, 100-seed fresh weight,and soluble sugar content(dry weight basis) ;but medium for pod length,pod thickness and pod width and relatively low for number of grain per pod. In vegetable quality breeding,the comprehensive sensor quality evaluation is the most important criterion. According to the correlation,partial corrlation and path coefficient anslyses, among the six first class sensor quality traits,i.e.appearance of grain and pod,cooked taste,mouth feeling of raw grain,grain color, cooked smelling,hand shelling of raw pod,the first three had significant and relatively large direct effect on the comprehensive sensor quality value; pod thickkness,pod length,and 100-pod fresh weight had significant direct effect on appearance of grain and pod; sweetness as well as soluble sugar content was a significant major factor to cooked taste;raw grain hardiness had significant negative effect on raw mouth feeling. In breeding for quality of vegetable soybean, the selection for comprehensive sensor quality should be based on the six first calss sensor quality traits with emphasis on appearance of grain and pod,cooked taste,and mouth feeling of raw grain;and the following component traits,such as 100-pod fresh weight, pod length, pod thickness, soluble sugar content, deli-ciousness,beany flavor,glutinosity and hardiness could be used as assistant indicators for a better evaluation of the sensor quality of breeding materials.
Abstract:Twenty eight taro materials in Yunnan province were analyzed using RAPD method, showing abundant genetic diversity at DNA level. Suitable random primer sequence and optimized PCR procedure of RAPD technique were screened out for Colocasia esculenta . The cluster analysis for RAPD markers were made and it was found that the result could be preliminarily classified by parts of botanic characters.
Abstract:The expression of wheat grain protein content in F1 as well as descendant F2 were studied. The result showed that the genes that control protein content transmitted to the descendants were mainly based on additive effect, but also with the non-additive effect. The grain protein content of F1 was highly related to the average value of both parents,and the protein content in descendant F2 appeared in normal distribution. The variance of general combining ability is larger than that of special combining ability. The heritability in broad and narrow sense were calculated.
Abstract:The purpose of this study was to find out reasonable number of markers in marker-assisted selection for backcrossing breeding in soybean. The lines lacking lipoxygenases with the genetic background of Ludou 4 were used as materials; their targeted genes were detected by IEF-PAGE, and the genetic background were analyzed using SSR markers,to obtain the ideal lines for further backcross. Through the relevant analysis of genetic background recovering ratio, the appropriate marker numbers and selection method in marker-assisted selection were established. A procedure was useful in marker-assisted background selection, that is, first to use limited number of markers to screen all the individuals, eliminate the individuals not fitting the requirements, then use more makers to screen the residuals. With this method, ideal individuals can be obtained with high efficiency. Some candidate lines were chosen for further backcrossing with Ludou 4 in order to accelerate development of near-isogenic lines of Loudou 4 with different types of lipoxygenase.
Abstract:Identification and evaluation of major agronomic and quality traits in the newly introduced Italian wheat were carried out. The results showed that they performed well in terms of the content of protein and wet gluten and plant height, grain number of per spike. The corre/ation analysis indicated that the higher value of sedimentation and content of wet gluten and protein were related to short stalk and earlier heading.
Abstract:The peroxidase isozyme of functional leaves of Allium ascalonicum L. , A. cepa L. and A. fis-tulosum L. was analysed. The relationships among three species and the relationships among the varieties of A. fistulosum L. were distinguished. The relationship between A. ascalonicum L. and A. cepa L. was nearer than that between A. ascalonicum L. and A. fistulosum L.
Abstract:A study on inheritance of resistance to bacterial speck disease was carried out by conventional crossing between two resistant and three susceptible varieties of tomato. Resistance in F1, F2 or BC1 was identified by inoculations with bacterial of PST. All the Ft progeny is resistant to the disease. The resistance of F2 progeny was statistically consistent with the ratio of 3 to 1, and the BC1 progeny was accord with the ratio of 1 to 1. The results showed that a single dominant gene controlled the resistance in the two tomato varieties, Hong Zhen Zhu and Mei Wei Ying Tao.
Abstract:Content of crude starch of totally 332 newly collected accessions of sweet potato were evaluated. 58 varieties were identified as germplasm with high crude starch. 36 varieties were found to have both high starch content and high dry matter content. 5 varieties were identified as drought tolerant germplasm. 29 varieties had storage tolerance. Several varieties were identified as the accessions with excellent high starch content by comprehensive evaluation.
Abstract:The pedigrees of main seedless grape varieties and entries bred in the world were analyzed. The results showed that Thompson Seedless was the main seedless source in seedless grape breeding. Most of seedless varieties and entries were the derivatives of the old varieties. Monukka and Russian Seedless are the seedless sources of some seedless varieties. Besides the segregation of characteristics due to sexual reproduction, natural mutation is an important sources of variation in seedless grapes.
Abstract:The South and South-west parts of China are rich of wild rice resources because of the humid and warm climates. There are three species of wild rice in China, that is O. rufipogon , O. officinalis and O. meyeriana . Based on previous investigations, O. rufipogon is the most endangered wild rice species and Chinese government began to carry out in-situ conservation programs from 2000. During the construction of in-situ conservation of wild rice, four different methods were applied. This paper described the methods and discussed the related issues of in-situ conservation in China.
Abstract:Recently, the applications of near-infrared reflectance spectroscopy (NIRS) in quality analysis are more active in plant breeding. The applications of NIRS in quality analysis and evaluation of germplasm, plant breeding programs, etc. were discussed.
Abstract:According to wheat breeders' experiences, the paper explained the importance of selecting Bridge materials. Wheat breeding generally deperds on two aspects, one is dwarf male - sterile wheat improvement and enhancement in agronomic characteristics and high quality, the other is pyramiding the genes of controlling big grain, big spike, powdery mildew and other diseases resistance.
Abstract:Using acid polyacrylamide gel eletrophoresis(APAGE), the gliadin variation of 11 Ae. kotschyi accessions and its progentiors, 2 Ae. longissima accessions and 6 Ae. umbellulata accessions were analyzed. Thirty-two gliadin bands were separated by electrophoresis and thirty-one out of them showed polymorphism (96.88%). Each material had 10 to 17 bands and only 1 band was involved in all of the 11 Ae. kotschyi accessions . The genetic distance (GD) of 11 Ae. kotschyi accessions based on gliadin ranged from 0 to 0. 704, with an average of 0.409. The patterns separated in the 11 Ae. kotschyi accessions were mostly derived from Ae. longissima or Ae. umbellulata , though 8 bands weren't found in the two progentiors. Polymophism of Ae. kotschyi (96.88 % ) was obvious higher than Ae. longissima (52. 94 % ) or Ae. umbellulata (88. 89 % ); 4 out of the 11 Ae. kotschyi accessions had specitie bands. It probably indicated that the r region in Ae. kotschyi had been changed in comparison with that of Ae. longissima or Ae. umbellulata .
Abstract:The upland rice variety IRAT359 has no fine hair in leaf and grain husk. It has higher tillering a-bility and drought resistance, and higher grain yield and grain quality. It can be cultivated in Yunnan, Guizhou, Sichuan and Guangxi provinces with irrigation condition, as well as Yangzhi river area with more amount of rainfall.
Abstract:The karyotype of Caragana microphylla Lam. was analyzed on the lever of cells It couldbe concluded that the Chromosome number of the somatic cells is 2n = 16. The karyotype formula is 2n = 2x = 16 = 14m (2SAT) +2M.The result of chromosome examination showed that it belongs to"1A"type according to Stebinns karyotypic asymmetry.