Abstract:The characteristics of 358 varieties released in last century at 18 European countries were studied systematically. Variations of plant height, kernel number per ear and 1000-kernel weight were very rich. Indeed, plant height has been decreased significantly since the beginning of last century, and kernel number per spike has been increased. No association was detected between released time and 1000-kernel weight. The influence of plant height and heading date on both kernel number/spike and 1000-kernel weight was also analyzed. Importantly, some accessions with breeding potential traits were recommended to breeders. Pedigrees of several varieties were also presented in this paper.
Abstract:The mature embryo sac fertility, formation and development of embryo sac of 141 accessions of O. rufipogon Griff. collected from the six sampling sites in Gaozhou, Guangdong Province were studied by using the technology of whole-mount stain-clearing confocal laser scanning microscopy (WCLSM). The results showed that some abnormal phenomena to different extent, such as abnormal embryo sac with non-female germ unit, abnormal embryo sac with polar nuclei in position, abnormal embryo sac with polar nuclei in number and embryo sac abortion, etc., were found in mature embryo sac. Those abnormal embryo sacs having abnormal fertility dued to no normal eggs, which caused seed setting rate to drop. The mean percentage of abnormal embryo sac of all the 141 accessions was 11.11% and the highest one was 67.86%. Development of wide rice in Gaozhou was similar to that of O. sativa L., which belongs to the Polygonum type. Abnormal phenomena in different periods of embryo sac development, including degeneration of megaspore, embryo sac abnormality during the periods of two to eight nucleate etc., were found in the plants with low seed setting rate. Few pollens were found on the stigma of 69 accessions observed after pollination, which would cause low percentage of fertilization. It was considered that a few of pollen grains on the stigma was one of the main reasons making seed setting rate decrease. The comprehensive factors resulting in the low seed setting rate of wide rice in Gaozhou were discussed in this paper.
Abstract:The beginning of blooming, the period of fruit ripening, beginning of leaf falling, ending of leaf falling, fruit development period, nutrition growth period of 301 to 480 peach cultivars were investigated at National Peach Genetic Collection in Zhengzhou. A kind of new descriptors and reference cultivars were given for peach by statistical data. These descriptors were recorded on 1 to 5 Grade. In generally, two reference cultivars were given, one USA cultivar, another cultivar which is planted widely in China.
Abstract:6 nurseries of INGER (International network for genetic evaluation of rice) including IRBPHN, IRGMN, IRBN, IRBBN, IIRON and IRFAON were carried out in Guangdong Academy of Agricultural Sciences of South China from 2001-2005. 1778 rice germplasm resources of INGER were tested. Numbers of germplasm with good agronomic characters were evaluated and selected for rice breeding. Nine new varieties used 4 gerplasm resources of INGER with good commercial qualities, high yields and resistance were passed the evaluation and made registration in Guangdong province and their plant area was up to 250000ha. These varieties made a great economic contribution and ecological effective in rice yield and management of brown plant hopper, rice blast and rice bacterial in the province. About 200 resistant gerplasm of rice were restored in the Plant Protection Research Institute and about 5000 gerplasm of rice were stored in the rice gerplasm store of the Rice Research Institute, Guangdong Academy of Agricultural Sciences. The gerplasm of rice from INGER in Guangdong take an important contribution in raising the level of studies on resistance to insect pest and disease, rice breeding and gerplasm utilization.
Abstract:In the paper, genetic variation of 52 transgenic insect-resistant cottons was analyzed using SSR and AFLP molecular markers. The results showed among 61 SSR primers 4 could produce polymorphic markers. A total of 102 DNA fragments was scored, among which 25(24.51%) bands were polymorphic. The number of DNA bands per primer ranged from 17 to 30. Nine AFLP primer combinations were selected to perform AFLP fingerprinting from 100. The total bands and polymorphic bands were 618 and 33(accounted for 5.34%), respectively. The number of DNA bands per primer combination ranged from 47 to 81. Mean pairwise genetic distance of 52 varieties (lines) was 4.21, with the range of 2.00 to 5.57. Mean genetic distance for each variety ranged from 3.73 to 4.75. The limited genetic variation was revealed by these results in the population. Based on dendrogram of SSRs and AFLPs, 52 varieties (lines) were divided into three SSR/AFLP-based groups (SAGs). However, SAGs was not accordance with geographic origins of tested varieties (lines).
Abstract:Single PCR reaction with two pairs of PCR primers designed on the markers respectively tightly linked with Cf-9 and Tm-1 genes in tomato, which be resistant to leaf mold and tomato mosaic virus. For the genes the PCR products were almost completely correspond to the amplified bands produced by single PCR primer. Among them, 560bp fragment linked with Cf-9 gene was amplified in both resistant and susceptible tomato lines. The amplified bands from susceptible and resistant lines were distinguishable after cleavage with the restriction enzyme TaqI. Genotype with Cf-9 gene could produce respectively 450bp, 330bp and 290bp bands. Susceptible genotypes could produce respectively 450bp and 290bp fragments. 750bp fragment linked with Tm-1 gene was amplified in resistant tomato line. The amplified bands could not be cleavaged with the restriction enzyme TaqI. The replicated stable results proved that two resistant genes could be identified simultaneously by using corresponding PCR primer under adaptable condition. This system compared with single primer PCR would be time saving, less labor and low cost. It could bevery useful for marker-assisted selection during early stage in tomato and efficiently speed up breeding procedure.
Abstract:Random amplified polymorphic DNA (RAPD) markers were used to estimate genetic diversity of Liriodendron. Fourteen primers generated 235 bands from 131 samples. It was indicated that Liriodendron has high genetic diversity. (1)The polymorphic bands percentage of L.chinense (Hemsl.)Sarg., L.tulipifera L. and hybrid clones ware 88.98%,91.06% and 89.98% ,respectively. (2)The genetic variation was observed within populations. (3)Clustering data indicated that the hybrid clones is close to L. tulipifera L. in heredity. Basic data were provided for further studies on the genetic variation, selection and evaluation of Liriodendron.
Abstract:Effect of 300mmol/L NaCl stress on salt injury index, electrolytic leakage, proline content and soluble sugar content in pumpkin seedlings of 19 varieties was investigated. The results showed that salt injury index, electrolytic leakage, proline content and soluble sugar content increased with prolonging time of NaCl stress. It was suggested that salt injury index and electrolytic leakage could be suitable for selecting salt tolerance of different pumpkins. In this research, it was also found that Q1(Cucurbita moschata Duch. Qingli) was the most salt-tolerant of salt stress, H2(Cucurbita maxima Duch. Heimi) and H3(Cucurbita ficifolia Bouche.) were sensitive to salt stress, and others were in middle.
Abstract:The grain yields and nitrogen use efficiencies of 29 varieties were studied. The results indicated that there were huge differences on grain yields among the tested varieties. Based on the Cluster analysis of the grain yields from deficient-N condition, the tested varieties were classified into three categories, including high-N efficiency group, mid-N efficiency group and low-N efficiency group. The high-N efficiency group contained few tested varieties. Under deficient-N condition, there were little differences on total nitrogen content of plant at maturity stage among the tested wheat varieties. The nitrogen concentration of plant, biomass, nitrogen use efficiency (NUE), nitrogen uptake efficiency (UPE) and nitrogen utilization efficiency (UTE) were all the highest in varieties with high-N efficiency, then next in varieties with middle-N efficiency, and the lowest in varieties with low-N efficiency. The high efficiency of nitrogen in wheat under nitrogen stress condition comes from the higher acquisition capacity, assimilation and metabolic capacity.
Abstract:In order to screen watermelon varieties in salt tolerance, germination experiments of 23 genotype watermelon varieties were done in 7 NaCl concentration . The results showed germination rate decreased with the NaCl concentration increasing and in mostly varieties were equal or increased comparing with those treated in 40-80mmol/L. Under 80-160mmol/L NaCl stress, the significant correlation was existed between 1000-grain weight and germination rate, among which the largest correlation coefficient was 0.606. Effects of the same NaCl concentration on the lateral root numbers, root length, root fresh weight, hypocotyls length and salinity injure index among different watermelon varieties were different ,and the results indicated that the tetraploid watermelon possessed higher salt tolerance than diploid. By the dendrogram of cluster analysis according to 5 principal components (germination rate, lateral root,et al), 23 varieties were affiliated with 4 clusters and the second cluster were identified to be best and salt tolerance of 6 varieties were better.
Abstract:Four lines including Jinhan125,Xiye501 and their cross offspring were selected as test materials. Physiological and ecological indexes relevant to drought-tolerance in seedling and flower-podding stage were determined by laboratory testing and field observation. In the condition of normal water supply and drought stress,the flower-podding stage was the most sensitive stage to water content in whole stages. We determined relative water content,ability of water holding,proline content,activity of POD,SOD,EST and analyzed their bands. The result indicated that the order of drought-tolerance was as follows: Jinhan125,73-1,73-2,Xie501,73-3,73-4.
Abstract:This paper made an identification about six agronomic trait of Yihui 1577 including lemma hair, phenor reaction, the first and second internode's length, the hull color while heading, leaf hair and grain shape with the morphological index method founded by Prof. Chen Kansheng. This study has proved Yihui 1577 belonging to japonicalinous restorer line. Yield combination analysis of Yihui 1577 was made by partial complete double cross design with 4 CMS lines and 6 restore lines. The result showed that the general combination ability effect value of Yihui 1577 and Minghui 63 was 0.226 and -0.113, indicating Yihui 1577's general combination ability was prior to Minghui 63's.
Abstract:Thirty hybrids and their 13 parents (3 male sterile lines and 10 restorer lines) were studied on the combining ability and heterosis for rice quality. The results showed that:(i) Most quality traits of rice hybrids had the measurements between their parents and no significant heterosis except the grain weight showed the over-high-parent heterosis, grain chalkiness had positive average heterosis. (ii) Male sterile lines and restorer lines had a great effect on the hybrid rice quality. Grain length, grain width and amylose content heavily depended on the male sterile lines, but head rice rate, grain weight, chalky grain rate, grain chalkiness and alkali spreading value greatly depended on the restorer lines than the male sterile lines. (iii) Parents Guangzhan 63-4S, Yangdao 6, R527 and Zhenhui 084 had good GCA and SCA,and can be widely used for new quality hybrids breeding. Teqing and Yanghui 559 had the low GCA and SCA and less significance for rice quality breeding.
Abstract:Rice anthocyanin is an important bioactive compound that has been the highlight of functional rice research and development. Current researches on biosynthesis and component of rice anthocyanin, especially on the influence elements, genetics research and molecular mechanism of rice anthocyanin content, and the identification, screening and innovation of rice germplasm with high anthocyanin content were reviewed. The strategy of corresponding researches on functional rice for high anthocyanin content was discussed furthermore.
Abstract:A lot studies in wheat molecular biology need to do PCR testing to many accessions of wheat samples. Thus it is very necessary to establish a rapid DNA isolation in wheat. A rapid DNA isolation method built in rice and maize was tried in wheat after performing some modifications. The modified DNA extraction method needs even less time. With the DNA isolated with this method, 1.5kb fragment could be amplified stably. Besides the DNA quantity extracted with this method was quite considerable, one sample could meet 50-100 PCR reactions. So the DNA samples from this rapid isolation method can also be used to do primer selection, gene mapping or other PCR assays.
Abstract:According to the principle that geographical and genetical distant materials have high heterosis because of genes complement, we crossed high yield and good agronomic characters line origining from Japanese soybean blood as female parent and a promising line having high protein content and derived from wild soybean as male parent. The soybean frogeye leaf spot was inoculated in early generations, and in advanced generations the quality had been analyzed and the soybean phytothora rot was inoculated. By directed selective breeding the new elite soybean germplasm that have multiple high protein, diseases resistance and high yield genes was derived, it had abundant genetic basis, its protein content was above 45 %, and it was resistant to frogeye leaf spot and phytothora rot.