Screening and identification of salt tolerance soybean varieties and germplasms

Soil salinization is a globally prevalent abiotic environmental stress.The imbalance of ions caused by high concentrations of sodium chloride results in a 40%reduction in soybean yield.Soybean,as an important crop for soil quality improvement,necessitates the identification of salt-tolerant varieties and germplasms to effectively utilize and enhance saline-alkali land.In this study,we assessed the salt tolerance of 435 soybean varieties and germplasms during the seedling stage.Among them,Qihuang34,You2104,Hongzhudou,Pamanheidou,and Osage exhibited grade 1 salt tolerance rates surpassing other tested materials.Furthermore,Hongzhudou and Qihuang34 demonstrated higher salt tolerance during germination and emergence stages based on their elevated rates of emergence,salt tolerance index,chlorophyll content,and shoot fresh weights.Overall findings provide valuable resources for molecular breeding efforts aimed at developing salt-tolerant soybean varieties suitable for cultivation in saline-alkali soils.

Protection and Utilization of Chinese Giant Salamander Germplasm Resources

Chinese giant salamander(Andrias davidianus)is salamander germplasm resource that only distributed in China.It is the material basis of the evolution principle research,genetic research and artificial breeding.Since the 1990s,overharvesting,water pollution and habitat changes have seriously destroyed the germplasm resources of A.davidianus,their population density has decreased since then.Strengthening the protection and rational utilization of A.davidianus germplasm resources are key factors in impacting the healthy,stable and sustainable development of A.davidianus industry.Under the above background,we discussed the current problems with the protection for A.davidianus germplasm resources,put forward suggestions for the conservation of A.davidianus germplasm resources.It is expected to provide a reference to effective protection for A.davidianus germplasm resources,and provide a scientific foundation for further studies,so as to promote the high-quality development of related industry.

Evaluation and Exploration of Citrus Germplasm Resources in the Origin of Shatangju(Citrus flamea Hort.ex Tseng Shiyueju)

[Objectives]To protect the local rare citrus germplasm resources and further develop and cultivate new citrus varieties.[Methods]The germplasm resources of Shatangju(Citrus flamea Hort.Ex Tseng Shiyueju)in Sihui City of Guangdong Province and other 8 citrus varieties from the same origin were evaluated.The appearance characteristics of tree shape,the length and thickness of shoot at each shoot stage,the appearance characteristics of leaves and the fruit quality of each variety were investigated.[Results]Through the comparison of various citrus varieties grafted with sour mandarin,the results showed that the overall advantages of the length and thickness of the shoots of Shatang tangerine in summer and autumn were more prominent,which was conducive to fruit setting.The sprouting time of the three shoots of each variety was different,and there were sporadic sprouting phenomena in different seasons,so the growth was different,and the length and thickness of the shoots were different in different seasons.There were significant differences in shoot length and diameter among different varieties in the same season.The coefficient of variation of Shatangju's leaves was low,and the traits were stable;leaf shape,leaf base shape,leaf margin and other indicators among the three shoots of the same variety and the differences among the same shoots of different varieties were compared.All varieties had strong flavor,separately sweet and sour,sweet and sweet taste.Shatangju has many segments,orange pericarp,rough texture,easy peeling,and high oblate fruit shape.The orange pericarp was favored by the participants,while the rough and thick peel was not favored by the participants.[Conclusions]Based on the improvement of local varieties,it is recommended to improve the smoothness of pericarp,reducing the thickness of pericarp and improving the flavor of fruit will be conducive to increasing sales.In the cultivation process of various quality resources,especially in the period of fruit growth and development,the plan of nutrition and fertilization should be formulated according to the rules of fruit growth and development,the rules of yield formation and the rules of quality composition,so as to establish the integrated nutrient management system of various varieties.

Documentation Concordance,Sharing and Utilization of Tea Germplasm Resources in Yunnan

In this paper,the research achievements and progress of Yunnan tea germplasm resource in past sixty years are systematically reviewed from the following aspects：exploration,collecting,conservation,protection,identification,evaluation and shared utilization.Simultaneously,the current problems and the suggestions about subsequent development of tea germplasm resources in Yunnan were discussed,including superior and rare germplasm collection,tea genetic diversity research,biotechnology utilization in tea germplasm innovation,super gene exploration and function,the construction of utilization platform,biological base of species and population conservation.

Research on Background and Utilization of Germplasm Resources in Maize

[Objective] The research aimed at introducing the background and utilization of germplasm resources in maize.[Method] The research progress on genetic background and utilization of maize germplasm resources was comprehensively reviewed in this paper,including maize heterotic groups and heterotic patterns,their flexible application in breeding and the utilization of various types of original materials.[Result] The results show that germplasm resource is the premise and basis for maize breeding.In-depth understanding and a reasonable selection of germplasm resources can significantly improve the breeding efficiency and speed up the breeding process.At the same time,it is considered that the selection and construction of original materials in maize breeding can not be limited to the heterotic groups and heterotic patterns,but has to be used reasonablely according to different types of germplasm resources and individual breeding objective and idea as well.[Conclusion] This study had broadened the idea and provided inspiration for the maize breeding practice in China.

Study on Present Status of Plant Germplasm Resources Conservation and Countermeasures

Plant germplasm resources is the material foundation and key point for agricultural production, crop breeding and bioengineering. China is one of the centers for the origin of the cultivated plants worldwide, as well as one of the countries with most abundant plant resources and the highest biodiversity. Strengthening research in the conservation and utilization of plant germplasm resources is of significant value and importance. In this study, the present status of conservation, utilization, and existing problems of plant germplasm resources in China and around the world were reviewed; further, through analyzing measures taken by global countries for plant germplasm resources protection, countermeasures for plant germplasm resources conservation in China were also presented from three aspects, namely, collection and conservation, information network construction and national legislation and policies.

Research Progress on Germplasm Resources of Common Bean

The origin, classification, utilization and evaluation of germplasm resources, and breeding methods were introduced. The researches of biotic or/and abiotic stress, exploration of genomics and proteomics in common bean in recent years were reviewed in this paper, in order to provide theoretical reference for utilization and innovation of germplasm resources in common bean.

Screening of Drought Stress Indicators and Analysis of Drought Resistance in Cultivated Rice Germplasm Resources in Guangxi

This study aimed to screen drought stress indicators and analyze the drought resistance in 105 cultivated rice germplasm resources in Guangxi Zhuang Autonomous Region under drought stress in the whole growth period based on D value of seven morphological traits including panicle neck thickness,effective panicle number per plant,1 000-grain weight,filled grain number per panicle,total grain number,seed setting rate and yield per plant.According to the results,under drought stress,yield per plant exhibited significant positive correlation with panicle neck thickness and exhibited extremely significant positive correlation with other five morphological traits.Based on the identification and evaluation of comprehensive drought-resistance index D value,seven highly drought-resistant cultivated rice varieties were screened,accounting for 6.67％.Upland rice germplasm resources in Guangxi Zhuang Autonomous Region possess strong drought-resistance capacity,which could be used to screen highly drought-resistant rice germplasm materials.This study provided material basis and theoretical reference for breeding drought resistant rice cultivars in Guangxi Zhuang Autonomous Region.

Identification of Faba Bean(Vicia faba L.)Germplasm Resources in Hubei Province and Evaluation on Their Main Agronomic Traits

Through field observation and lab analysis, 13 agronomic traits, including plant height and effective branching number per plant, etc., of 207 faba bean （Vicia faba L.） germplasms saved in Crop Middle-term Genebank of Hubei Province were evaluated, moreover, the identification on the disease resistance and the quality was carried out on parts of germplasm resources. The results showed that the faba beangermplasm resources in Hubei Province were abundant, the variation range of agronomic traits like the growth period, plant height and 100-bean weight, etc., was great, and the range of choice was wide. In the aspect of quality, there were 9 germplasms withthe content of crude protein higher than 30%, and the variation range of amylose content in total starch was large, which provided excellent sources of parents for breedinq hi.qh-quality faba bean varieties in Hubei Province.

Collection and Preservation of Cashew Germplasms Resources Research Progress in China

The cashew tree is a typical tropical nut tree species in China, and the collection, identification and innovated utilization of excellent cashew germplasm resources are of great significance to increase the income of farmers and agricultural benefits in the tropical area of China. This study summarized the major advances on cashew germplasm resources in China, analyzed the major research progress and existing problems from the aspects of the collection and evaluation, resistances, genetic diversity of cashew germplasm resources, and put forward the work ideas to analyze the construction of core germplasm bank and the genetic stability of the major biological characteristics of cashew germplasm resources, which were of important significance for the improvement of the cultivar classification and resource evaluation system of cashew germplasm resources in China.

Evaluation and Screening of Aceraceae Germplasm Resources

[Objective] The aim was to screen out excellent Aceraceae germplasm resources which can be applied in gardens and urban landscape. [Method] The set of 17 biological traits of 24 Aceraceae species were observed and recorded. Taking into consideration aesthetic evaluation of different groups of people, the studied species were graded in quantitative scale. The species with higher overall score is considered better germplasm resource. [Result] The Aceraceae species with top ten highest overall scores were： Acer japonicum ＇Aconitifolium＇ （45.5）, Acer palmatum var. thunbergii （43.8）, Acer palmatum （41.8）, Acer elegantulum （39.2）, Acer elegantulum var. macrurum （39.2）, Acer rubrum （39.1）, Acer Cordatum（38.8）, Acer truncatum （38.3）, Acer olivaceum （37.7） and Acer acutum （37.3）. [Conclusion] The above ten species can be used preferentially as excellent Aceraceae germplasm resources for landscaping.

Fruit Anatomy of sect. Paracamellia with Reference to Their Significance of Germplasm Resources Exploitation

[Objective] To utilize the germplasm resources,new systematic evidence for the classification of sect.Paracamellia,genus Camellia is found in this article.[Method] Fruit anatomy of 10 species representing sect.Paracamellia was investigated.And the main component of sect.Paracamellia in the genus Camellia was studied by MVSP software.[Result] The exocarp was thin;mesocarp was broad,having a large number of stone cells;endocarp was lignified,and separated easily from seed.The principle components analysis suggested that the distance between species was far,showing far relation;the current study did not support the formation of Camellia grijsii（C.grijsii）and Camellia yuhsienensis（C.yuhsienensis）,Camellia shensiensis（C.shensiensis）should not be recognized as a variety of C.yuhsienensis.In addition,it also proved Ming＇s combining of Camellia confusa（C.confusa）and Camellia kissi（C.kissi）was unnatural.[Conclusion] The study provided theoretical basis for the development and application of sect.Paracamellia in the genus Camellia.

Study on Germplasm Resources of Tartary Buckwheat (Fagopyrum tataricum) in Shanxi Province

This study analyzed the tartary buckwheat recorded in the books Catalogue of Crop Germplasm Resources in Shanxi Province and Catalogue of Chinese Buckwheat Germplasm Resources by Excel 2003 and DPS 7.5 from the aspects of distribution areas,main agronomic traits and nutritional components,so as to lay a foundation for the selection of excellent buckwheat germplasm resources and improvement of buckwheat varieties.The results showed that different buckwheat varieties vary in plant height,node number of the main stem,grain weight per plant,grain weight per plant and kilo-grain weight.Compared with the national average values,buckwheat in Shanxi is higher in protein and fat,but lower in vitamin E and vitamin PP;it is rich in Ca,Mg,Cu,P,Se,Fe,Mn and Zn;and it contains 18 amino acids with the content of glutamic acid being the highest and the content of tryptophane being the lowest.After analyzing and classifying the tartary buckwheat germplasm resources recorded in Catalogue of Grop Germplasm Resources in Shanxi Province and Catalogue of Chinese Buckwheat Germplasm Resources,breeders could breed new varieties with high yield and quality and strong stress resistance by crossbreeding with these germplasm resources.

Track Monitoring on Viability of Rice Germplasm Resources and Regeneration under Low Temperature Storage

53 rice germplasm resources warehoused during 1981-1984 were regarded as materials to monitor the viability at warehouse time and different years after warehoused. The results showed that seed germination rates of different rice germplasm resources assumed descending trend in storage, with annual decreasing rate between 0.12%-3.05% ; the seed germination rates of most cultivars were above 75% after stored for 26 years; forecasting analysis based on the germination rate of 75% as reference showed a huge difference of safe storage life for different rice germplasm resources, ranging from 12 to 50 years, even longer time. The results suggest that track monitoring on viability and regeneration of rice cultivars is of great importance for germplasm resources conservation.

Morphological Diversity Analysis of Red-seed Watermelon (Citrullus lanatus ssp. vulgaris var. megalaspermus Lin et Chao) Germplasm Resources

[Objective] This study aimed to analyze the morphological diversity of red- seed watermelon （Citrullus lanatus ssp. vulgaris var. megalaspermus Lin et Chao） germplasm resources. [Method] Multiple cluster analysis and principal components analysis on the morphological traits of 51 red-seed watermelon germplasm resources were carried out. [Result] The coefficient of variations （CVs） of 39 morphological traits in 51 red-seed watermelon idioplasm resources ranged from 5.37% to 66.95%, with an average of 22.87%. The average of Shannon diversity information indices was 1.55. Among them, the Shannon diversity information index of seed length was the highest （2.16） and that of seed shell figure pattern was the lowest （0.32）. In ad- dition, the morphological diversity information indices of quantity characters were higher than that of quality characters. The principal components analysis revealed that the variance contribution rates of the first, second and third principal compo- nents were 19.49%, 15.32% and 9.55%, respectively. Cluster analysis divided the 51 materials into three broad branches based on the morphological traits. There was only one material in the fist branch and two in the second branch, and all the three materials were wild. The other 48 materials were divided into the third branch and all of them were cultivars. [Conclusion] This study provided a theoretical basis for the protection and utilization of red-seed watermelon resources.

Characterization of 124 Flue-cured Tobacco Germplasm Resources

[Objective] This study aimed to characterize 124 flue-cured tobacco germplasm resources, and to provide reference for making the best use of the existing flue-cured tobacco germplasm resources. [Method] A total of 124 flue-cured tobacco germplasm resources were studied via field experiment and statistic analysis to investigate characteristics of their growth period, morphologic characters, main agronomic traits, and economic characters. [Result] There were significant differences among the 124 flue-cured tobacco germplasm resources in growth period, morphologic characters, main agronomic traits, and economic characters. The coefficients of variation （CV） varied in a range of 7.9%-22.5%. Among them, CV of bud stage was higher, and that of corolla length was lower. Many germplasm resources were attacked seriously by black shank disease at the end of field experiment, including those with disease index higher than 90, like Kutsaga 110, TI706, Ky 151, KM10, Longshe, Chaoxian Kangchi, Kutsaga 51E, Yongding No.1, and those with disease index among 75-90 such as Liaoyan No. 8, Lingnong No.2, Shandong Duoye, 581, Cunjingyan, KRK26, and Special 400. The tobacco root knot nematode invasion was light in some germplasm or never happened in other germplasm resources. TMV happened sporadically. CV 87, Yunyan 99, Yunyan 85, K326, Yunyan 87, Zhubuo No.1, T64 and T66 produced higher yield, production value, proportion of good leaves and sold at a higher price. Finally, we screened out the germpalsm resources with good comprehensive economic values and high disease resistance such as CV 87, Yunyan 99, Yunyan 85, K326, Yunyan 87, Zhubuo No.1, T64, T66, Honghuadajinyan, G-28, Taiyan No. 8, 77089-12, Yunyan 97, K346, V2, K149, NC567, NC297, Yunyan 201, Yunyan 203, KRK22. [Conclusion] This study provides reference for making better use of tobacco germplasm resources, and breeding new varieties.

RAPD Analysis of Germplasm Resources of Kudingcha Species in Oleaceae

The random amplified polymorphic DNA marker （RAPD） was applied to detect the genetic relationships and diversity among 21 germplasm materials of Kudingcha species in Oleaceae, which involved 8 species, i.e., Ligustrum robustum （Roxb.） Blume, L. henryi Hemsl., L. japonicum Thunb, L. japonicum Thunb. var. pubscens Koidz, L. lucidum Ait., L. pedunculare Rehd, Osmanthus masumuranus Hayata, and L. delavayanm Hariot. 20 RAPD primers selected were applied for the amplification on the 21 germplasm materials mentioned above. 427 bands were obtained, and the percentage of polymorphic bands （PPB） was 97.7%. The genetic similarity coefficients （GS） ranged from 0.1522 to 0.8322 with an average of 0.5466. There was a significant genetic difference among germplasm materials of Kudingcha species in Oleaceae, and UPGMA cluster based on the GS of RAPD could distinguish all test germplasm materials clearly and indicated the relationship of the 8 species mentioned above, all of which indicated that RAPD markers could be used for the studies of genetic diversity and relationship and classification of germplasm resources of Kudingcha species in Oleaceae. Analysis results of RAPD showed that L. japonicum Thunb. var. pubscens Koidz has closer genetic relationship with L. pedunculare Rehd and further genetic relationship with L. japonicum Thunb. among all tested species. The authors suggest that further research is needed to study whether L. japonicum Thunb. var. pubscens Koidz should be classified into a variata of L. japonicum Thunb, or should be considered as an independent species. The analysis results supported that L. pururascens Y. C. Yang should be combined into L. robustum （Roxb.） Blume.

Germplasm resources of three wood plant species enriched with nervonic acid

Nervonic acid(NA)is a very-long-chain monounsaturated fatty acid with pharmaceutical and nutraceutical functions that plays an important role in treating several neurological disorders.One major source of NA is plant seed oil.Here we report fatty acid profiles of seeds and germplasm diversity of six plant species,including three woody plants with high amounts of NA-enriched seed oil,Malania oleifera,Macaranga adenantha,and M.indica.M.oleifera had the largest seed(average 7.40 g single seed),highest oil content(58.71%),and highest NA level(42.22%).The germplasm diversity of M.oleifera is associated with its habitat but not elevation.Seeds of M.adenantha contained higher NA levels(28.41%)than M.indica(21.77%),but M.indica contained a significantly higher oil content(29.22%)and seed yield.M.adenantha germplasm varied among populations,with one population having seeds with high oil content(22.63%)and NA level(37.78%).Although M.indica grow naturally at a range of elevations,no significant differences were detected between M.indica populations.These results suggest that M.indica and M.oleifera have greater potential as a source of NA,which will contribute to constructing a germplasm resource nursery and establishing a selection and breeding program to improve the development of NA-enriched plants.

Safe conservation and utilization of peanut germplasm resources in the Oil Crops Middle-term Genebank of China

Peanut(Arachis hypogaea L.)is an important oil and cash crop in the world.Peanut germplasm collected in China are abundant,which provides important material guarantee for peanut breeding and industrial development.Here,the safe conservation technology and indicators of peanut germplasm resources in the Oil Crops Middleterm Genebank of China were expounded from three processes of storage,monitoring,reproduction and renewal.We summarized and reviewed the situation of conservation and utilization of peanut germplasm resources in the Middle-term Genebank in the past 20 years.The future research direction of peanut resources in the Oil Crops Middle-term Genebank of China is prospected.

Progress of the Research on the Conservation of Crop Germplasm Resources in China

In the last 20 years, China has made considerable achievements in the conservation of crop germplasm resources. A network for crop germplasm conservation has been established by the end of 2002, which includes a national long-term seed genebank and its duplicated genebank, 8 national medium-term seed genebanks, 30 national field genebanks. 2 national in vitro genebanks, and 3 in situ conservation sites including 1 for wild soybean and 2 for wild rice. More than 334 000 crop germplasm accessions are currently stored in the national long-term genebank, covering 35 families, 192 genera and 712 species, which rank in the first place in the world. More than 43 000 accessions of vegetatively propagated crops and perennial crops covering more than 900 species are conserved in the national field genebanks. In addition, 2 300 accessions are stored in the national in vitro genebanks. This paper reviewed the latest advances of techniques for safety preservation of stored germplasm in seed genebank, ultra-dried seed storage and in vitro preservation in China and discussed current highlights in germplasm conservation.