Abstract:Orchidaceae is one of the largest families in angiosperms， with a wide range of species and wide distribution. It has high ornamental value because of its peculiar flower type， rich flower color and long-lasting flowering period. Orchids are also one of the most traded flowers internationally， with extremely high economic value. The flowering time and flower quality are important traits that affecting the ornamental value of orchid. However， due to the mismatch between the natural flowering period of most orchids and market demand， low flowering uniformity， and poor flowering quality， the development of the orchid industry is greatly limited. Therefore， how to regulate the flowering period and improve the quality of orchid is of great significance for the production and application of orchid. This article provides a review of the flower bud differentiation process， flowering regulation techniques， and molecular regulation mechanisms related to flowering in orchid， based on domestic and foreign research. It summarizes the characteristics of flower bud differentiation in orchid， the existing problems in basic research and technology related to flowering regulation in orchid plants， the flowering pathways related to orchid， and the flowering mechanism and flowering regulation techniques related to Phalaenopsis. It proposes potential research directions for flowering regulation mechanisms and techniques in orchid， in order to provide reference for flowering regulation research， large-scale production， and quality improvement in orchid.

Abstract:Pepper （Zanthoxylum bungeanum Maxim.） is an important economic crop， integrating flavoring， medicine， oil extraction and ornamental， which has a long history and is widely planted in China. China is the origin of pepper and has found 45 species， 13 varieties， rich resources. Pepper like sunshine and have strong survival ability. However， pepper makes the cultivation and promotion of the limitations for its relatively poor low temperature resistance. Low temperature is the main environmental factor， which seriously affects the yield and quality of pepper and impedes the sustainable development of pepper industry. In this paper， we reviewed the current research status at home and abroad from four aspects， including the growth morphology， evaluation of cold tolerance， physiological and biochemical changes， and molecular response mechanism of pepper. The results showed that there are two methods to characterize the low-temperature tolerance of pepper：Natural identification in the field and indoor low-temperature treatment. Related studies on physiological changes in pepper mainly focused on four aspects：water content， biofilm structure（relative conductivity， malondialdehyde）， antioxidant enzymes （superoxide dismutase，peroxidase） and osmotic regulating substances （soluble sugars， soluble proteins， free proline）. The exploration of molecular response mechanisms in pepper has revealed multiple metabolic pathways that work together in response to low-temperature stress in pepper.Finally， this paper analyzes and looks forward to the current research direction of pepper in response to low-temperature stress， in order to lay a foundation for further identification and evaluation of Zanthoxylum bungeanum germplasm resources， research on cold resistance and the creation and cultivation of cold resistant germplasm.

Abstract:China is one of the important distribution centers for Begonia， with the Guangxi karst mountains representing a particularly concentrated area for sect. Coelocentrum. The distribution characteristics of these species are defined by a high diversity， small populations， scattered distribution， and fragile habitats. In recent years， human activities have increasingly interfered with the natural habitats of wild Begonia populations. In order to further understand the diversity， distribution characteristics and population status of Begonia species in Guangxi， an in-depth survey was conducted from 2017 to 2022 in the western cities including Chongzuo， Baise and Hechi. This survey focused on 66 Begonia species （including 53 officially published species or subspecies and 13 suspected new species） across nearly 140 wild populations. The study primarily recorded the habitats and growth conditions， and analyzed the data in conjugation with the literature and herbarium specimens. The findings revealed that while the majority of wild populations were in good condition of growth and regeneration， human activities， especially infrastructure development， tourism expansion， and artificial collection， have had certain impacts on some wild populations， with a few at risk of extinction. The resources of Begonia in western Guangxi are extremely rich， including some species that have yet been discovered or published， and there are many taxa with high ornamental value and development potential， especially sect. Coelocentrum. Based on the survey of the distribution and growth conditions of wild Begonia resources in western Guangxi， this study summarized the overall distribution characteristics and diversity， and proposed suggestions on how to further develop and utilize of these resources while ensuring their protection.

Abstract:Sichuan's complex and diverse terrain has nurtured rich plant resources. To clarify the geographic distribution and population size of buckwheat germplasm resources， in 2022-2023， the Wild Buckwheat Resource Survey Team（College of Life Sciences， Sichuan Agricultural University） conducted a survey and collection of resources in Sichuan province， China， mainly for the northwest and southwest mountains， and the Chengdu Plain， Sichuan Hills， including 30 counties （districts）. We collected a total of 156 wild plant germplasm resources of the genus Fagopyrum ［103 F. cymosum （Trevir.） Meisn.， 23 F. tataricum subsp. potanini， 3 F. esculentum subsp. ancestrale， 17 F. gracilipes （Hemsl.） Dammer. ex Diels， 5 F. leptopodum （Diels） Hedberg， 2 F. caudatum （Sam.） A. J. Li， 2 F. macrocarpum Ohsako et Ohnishi， 1 F. rubifolium Ohsako et Ohnishi］. The northwest of Sichuan province was found with the richest wild buckwheat species. F. cymosum （Trevir.） Meisn. is the wild buckwheat with the largest distribution， mainly distributed in the hilly areas of central Sichuan. The distribution of F. macrocarpum and F. rubifolium has extremely obvious regionality. There is a wide range of genetic variation between wild buckwheat resources in different habitats. Statistics on the companion plants of wild buckwheat resources show that Urtica fissa E. Pritz. and Bidens pilosa L. are the most numerous companion plants. This survey and collection not only enriches the buckwheat resource germplasm bank， but also lays the foundation for studying the distribution patterns of wild buckwheat and formulating protection measures.

Abstract:Based on the farmers' cognition and survey data， this article analyzed the Shaanxi excellent germplasm resources， which collected from the “Third National Survey and Collection of Crop Germplasm Resources”. These germplasm resources are mainly common bulk crops， with the highest number of vegetables crops and fruit， followed by grain crops. The characteristics of these superior resources are mainly high-quality， good appearance and strong adaptability， while taste is the most important quality trait concerned by farmers， followed by appearance and resistance. The distribution of crops is characterized by a higher concentration of fruit crops and vegetables in Guanzhong region and a greater amount of grain crops in southern Shaanxi region. The distribution pattern is influenced by both natural and human environments. Farmers' cognition can truly reflect farmers' subjective needs， choices of direction， and selection strategies or experiences. High quality is the main demand for farmers to retain resources， followed by appearance and adaptability factors. The selection direction is mainly to solve prominent problems， while taking into account other needs， leading to a significant correlation between main needs and their corresponding main superior traits， and secondary needs and their corresponding superior traits， with obvious signs of artificial selection. While the formation of excellent resources in Shaanxi province are influenced by the natural environment， artificial selection has made them more rich and colorful. The protection and utilization of Shaanxi excellent resources should fully consider the characteristics of resource distribution， focus on exploitation of resource value， and gradually improve the system of resource protection and utilization through establishing reasonable benefit mechanisms and management mechanisms.

Abstract:To enhance the utilization efficiency of wheat germplasm resources in China，broaden the genetic diversity of these resources， and identify superior parental lines for breeding to improve wheat quality， a study was conducted using 607 wheat germplasm samples from different time periods to comprehensively analyze the quality traits. Thirteen quality traits were evaluated using coefficient of variation，correlation analysis， and cluster analysis to access the quality characteristics of germplasm from different released periods. The results revealed significant variation in the 13 quality traits， with coefficient of variation ranging from 2.28% to 79.65%. Dough stability time exhibited the highest coefficient of variation， while viscosity peak time displayed the lowest dispersion， with greater dispersion observed among various trail indices of the germplasm resources from the periods after 2000. Comparative analysis of quality traits across different time periods showed a decreasing trend in protein content and wet gluten content of flour from local varieties（before 1949）to varieties from 1949 to 2000， and to varieties after 2000. Conversely， traits such as gluten index， developing time， and stabilily time， indicative of gluten strength， displayed an increasing trend over the years. Peak viscosity and breakdown exhibited a trend of varieties from 1949 to 2000 > local varielies > varieties from years after 2000， with significant differences observed among the three. Correlation analysis indicated varying degrees of correlation among the 13 quality indicators， with protein content， wet gluten content， and peak viscosity showing correlations with multiple other indicators， suggesting their potential as target traits for wheat breeding. The systemic cluster analysis categorized wheat germplasm into 6 groups， each displaying unique quality traits which are different from the quality traits of other groups. Group III was characterized by low flour water absorption and low gluten index， while group IV exhibited high protein content， high wet gluten content， and high peak viscosity. Additionally， four germplasms meeting the strong gluten standard based on protein content， wet gluten content， and stability time， and one germplasm meeting the weak gluten standard were identified. The findings of this study offer valuable insights and a theoretical foundation for the utilization of wheat germplasm resources and the breeding of high-quality wheat varieties in China.

Abstract:To evaluate the tolerance of different maize materials to salt stress during the germination period and to explore the salt talerance of hybrid maize materials from different hybridization patterns during the germination stage. This study used a 160 mmol/L NaCl solution to treat 152 maize inbred lines and 303 hybrid varieties under salt stress. Distilled water culture was used as the control， and salt tolerance during germination was identified using a paper bed culture method in a culture dish. The results showed that salt stress treatment significantly reduced the germination potential， germination rate， and germination index of maize materials. Trait correlation analysis revealed a highly significant positive correlation between different traits. Using the salt tolerance rate during the germination period and combining with the clustering analysis results， the inbred and hybrid materials were divided into five salt tolerance levels： Level I （high tolerance， 4 inbred lines， 17 hybrids）， Level II （tolerance， 19 inbred lines， 58 hybrids）， Level III （moderate tolerance， 47 inbred lines， 120 hybrids）， Level IV （sensitive， 33 inbred lines， 71 hybrids）， and Level V （high sensitivity， 49 inbred lines， 37 hybrids）. Based on the analysis of identity-by-descent （IBD） segments， 146 inbred line materials were divided into 8 groups. The salt tolerance of different groups of inbred line materials was as follows： European maternal group>Complex group>Inbred line 330 group>PB group>Lancaster group>Tangsipingtou group>PA group>Reid group. The hybrid materials are divided into 23 hybridization patterns based on the different parent material groups， among which European maternal group×PB group is the optimal heterosis pattern for salt stress tolerance during germination. This study identified the salt tolerance of inbred lines and hybrid materials， and selected 4 high salt tolerant inbred line materials and 17 high salt tolerant hybrid materials.

Abstract:Saline-alkaline stress is a critical limiting factor for high-yield and stable production of rice. Elucidating the effects of different saline-alkali soils on rice panicle morphology， and screening saline-alkali-tolerant rice germplasm accessions are of great significance to the breeding of saline-alkali tolerant rice varieties. In the present study， normal paddy soil was used as control （CK）， with two different types of saline-alkali soil being used as experimental treatments. Treatment I and II focused on salt and alkali stresses， respectively. A total of 164 japonica rice germplasm accessions were examined for 11 panicle traits. Then， multivariate statistical methods， such as correlation analysis， principal component analysis （PCA）， linear regression analysis （LRA） and path analysis were used for a comprehensive evaluation of the panicle traits under different saline and alkaline adversities. Under the two saline-alkali treatments， spike length （SL）， grain number per panicle （GNP）， grain density （GD）， grain number of primary branch （GNPB）， primary branch number （PBN）， grain number of secondary branch （GNSB）， and secondary branch number （SBN）， were significantly reduced if compared to CK. Compared with treatment II， Treatment I showed significantly increased in SL， GNP， secondary branch grain density （SBGD）， GNSB， and SBN. These findings suggest that salt stress exerts a less substantial impact on these traits than alkali stress. Under different treatment conditions， variations on the correlation among 11 panicle traits were noted. Particularly， a significant positive correlation between the thousand grain weight （TGW） and seed setting rate （SSR） under the two saline-alkali conditions was detected， while no significant correlation under CK condition was found. PCA with 11 evaluation index from CK， treatment I and treatment II suggested three major components， with cumulative contribution rate of 80.412%， 86.441% and 83.861%， respectively. Using LRA and PCA， GNP， GD， GNPB and PBN were selected as the key indexes for evaluating panicle morphology of japonica rice under saline-alkali condition. Five saline-alkali-tolerant japonica rice accessions， namely Liaogeng 1201， Pinggeng 8， Fengdao 508， Song 820， and Ninghui 1， were identified through a comprehensive evaluation value D of panicle traits， and they can be used as valuable parental lines for rice-plant-architecture breeding under intricate saline-alkali environments.

Abstract:In order to investigate the salt tolerance of Shanxi foxtail millet during germination， identify candidate genes associated with this trait， and elucidate the genetic mechanisms underlying germination traits under salt stress， a total of 333 core germplasms from Shanxi， China， were selected for assessing salt tolerance during germination. A stress of 170 mmol/L NaCl stress treatment was applied in a controlled light chamber to determine the salt tolerance during germination. The subordinate function value method was used to categorize the salt tolerance grades of the millets， and a comprehensive evaluation D value of five related traits， namely， relative germination potential， relative germination rate， relative root length， relative shoot length， and relative germination index， was used to access salt tolerance at the germination stage. In conjugation with the resequencing results of core germplasm， a genome-wide association scanning （GWAS） for salt tolerance at the germination stage was carried out. The findings revealed significant variation in salt tolerance in the collection， which were classified into five categories using the comprehensive evaluation D-value， with 17 exhibiting high salt tolerance. GWAS identified 84 single nucleotide polymorphism （SNP） loci associated with salt tolerance during emergence. Functional annotation was performed on the genes where the significantly associated SNPs were located. This led to the identification of the salt tolerance candidate gene Millet_GLEAN_10019153， which is associated with emergence. The outcomes of this study offer valuable references for the identification of salt-tolerant cereal germplasm and the mining of salt-tolerant genes.

Abstract:Lodging is a main problem affecting the yield of common buckwheat in central Gansu， China. This study used 76 common buckwheat germplasm resources from both domestic and international sources to investigate genetic diversity of 23 phenotypic traits that associate to lodging resistance. Through applying statistic methods such as Shannon-Wiener diversity index， correlation analysis， principal component analysis， regression analysis， cluster analysis and stepwise discriminate analysis， a comprehensive evaluation of the lodging resistance was conducted. The collection of common buckwheat exhibited high genetic diversity， with diversity indices ranging from 2.349 to 4.331 for different traits， among which the number of main stem branches was the smallest and the length of the second inter-node was the highest. Correlation analysis revealed correlations of varying degrees among the 23 traits. The principal component analysis showed that the first five principal components could represent 81.421% of the information of the 23 traits. Using a membership function method， a comprehensive score value （D） for lodging resistance was calculated， with an average D value of 0.469. The D value for Yuntianqiao 1 was the lowest （0.200） and the highest for TQ10-07（0.819）. Stepwise regression analysis identified eight traits， including plant height， stem height of center gravity， the first inter-node length and wall thickness， the second inter-node length， number of main stem branches， bending degree and stem resistance， as comprehensive evaluation indicators for lodging resistance of common buckwheat germplasm resources. Based on D value clustering， 76 materials were divided into four groups，among of which， 10 materials in class Ⅳ exhibited high lodging resistance and high D value， which could be used as parent materials for material innovation and breeding. This study showed that using a multivariate statistical analysis method for comprehensive evaluation of lodging resistance is feasible， providing a basis and reference for germplasm innovation and lodging-resistant breeding in common buckwheat in central Gansu， China.

Abstract:Broomcorn millet （Panicum miliaceum L.） is a diverse and ancient crop with rich germplasm resources. The use of fluorescent SSR markers enables the digital management and classification of these resources， facilitating their rational and efficient utilization. In this study， 258 broomcorn millet accessions from Inner Mongolia， China， were used to develop 12 fluorescent SSR markers， based on 85 pairs of conventional SSR markers previously developed by our research group， through multiple rounds of amplification， selection， optimization and modification （adding fluorescent labels to the 5'-end of the primers）. MapChart 2.32 was used to plot the chromosome location of these markers， ID Analysis 4.0 to assess the discriminating power of the markers， PowerMarker 3.25 and PopGen 1.32 for genetic diversity analysis， MEGA 11.0.10 for constructing the cluster diagram， and NTSYSpc2.11a for principal component analysis. A DNA molecular ID was created for the genotypes using a QR code generator. Genetic diversity analysis showed that there were 123 alleles in 258 materials amplified by 7 pairs of markers， with an average of 17.5714 alleles per marker. The mean values of effective alleles ， Shannon diversity index， Observed heterozygosity， expected heterozygosity ， Nei's gene diversity index and Polymorphism information content were 7.4622， 2.2270， 0.8021， 0.8372， 0.8353， and 0.8994. The results of capillary electrophoresis were encoded in a specific way， and only 7 pairs of fluorescent labels （RYW6， RYW8， RYW37， RYW40， RYW67， RYW124 and RYW125） were used to generate 258 strings and two-dimensional code DNA molecular identity cards of Inner Mongolia millet resources. This approach provided a molecular detection tool and theoretical basis for the classification management and rapid identification of the germplasm resources of Inner Mongolia broomcorn millet germplasm resources.

Abstract:Monilinia fructicola is the predominant species causing peach brown rot in China， and developing resistant varieties is crucial through screening resistant resources against this disease. In 2022-2023， peach fruits with a maturity index of 8.0-8.5 were collected from National Peach Germplasm Resources Garden （Zhengzhou， China） for artificial inoculation and screening. In total，150 accessions were evaluated by uninjured inoculation， and 37 accessions by injured inoculation. The percentage growth of infected fruits per day （PGIF） and lesion diameter growth rate （LDGR） were used to evaluate brown rot resistance. A 9-grade resistance evaluation system was established based on the average value of PGIF and LDGR with 0.5 standard deviation， respectively. The resistance of different germplasm， flesh texture， fruit types， and origin were compared， and the correlation between resistance indexes and other fruit characters was analyzed. PGIF by non-destructive inoculation was 7.68%， and the CV value was 69.69%. In its resistance evaluation system，grade 1 included 11 accessions resistant to fruit brown rot， grade 2 included 34 accessions， grade 3 included 28 accessions， grade 4 included 21 accessions， grade 5 included 20 accessions， grade 6 included 14 accessions， grade 7 included 16 accessions， grade 8 included 4 accessions， and grade 9 included only 2 accessions. The LDGR was 0.82 cm/d， and the CV value was 31.69%. In its resistance evaluation system，grade 1 contains 1 accession with strong resistance， grade 2 contains 3 accessions， grade 3 contains 5 accessions， grade 4 contains 5 accessions， grade 5 contains 7 accessions， grade 6 contains 8 accessions， grade 7 contains 5 accessions， grade 8 contains 2 accessions， and grade 9 contains only 1 accession. It was found that landraces exhibit relatively strong resistance to brown rot. The LDGR was negatively correlated with fruit acidity， and the PGIF was negatively correlated with fruit hardness. Collectively， 11 accessions resistant to fungal invasion and 1 accession resistant to fungal expansion were identified using non-destructive and destructive inoculation methods， respectively.

Abstract:Leaf color is closely related to plant photosynthetic efficiency and grain yield of wheat. The physiological yellow leaves were present in an artificially synthesized wheat Y223. The F₁ plants derived from the cross between Y223 and a normal green leaf variety Jinzuo 82 displayed intermediate phenotype in leaf color. Seventeen days after the emergence of Y223’s flag leaves， the segregation ratio for green leaf， intermediate， and yellow leaf types in the F₂ population Y223×Jinzuo 82 fits to 1∶2∶1， showing incomplete dominance of Y223’s yellow leaves. Using the bulked segregant analysis method， F₂ individuals with contrasting phenotypes were selected to establish green leaf pools and yellow leaf pools. From 569 SSR markers distributed on 21 chromosomes of wheat， 12 markers with consistent polymorphism between parents and green/yellow leaf pools were identified. Nine of them were located on chromosome 2B. These markers were used to genotype the F₂ population， and the yellow leaf locus， designated YL-2B， was mapped by five markers. YL-2B was flanked by markers Xbarc200 and Xbarc55， with genetic distances of 2.3 cM and 3.8 cM， respectively. By comparing the characteristic of dominance/recessiveness， yellow leaf phenotype， and marker linkage， YL-2B proved to differ from the reported yellow leaf loci on chromosome 2B， indicating that it is possibly a novel locus. This study clarifies the inheritance mode and chromosome position of the yellow leaf locus carried by Y223， which provides a reference information for gene cloning and understanding leaf senescence mechanism.

Abstract:Plant height is one of the key factors determining yield and stability in maize. This research aims to increase the individual yield of maize by optimizing the plant architecture. We have discovered a dwarf mutant， d309， in the mutagenized material of the maize variety B73， which was stably inherited through continuous selfing. Genetic analysis revealed that the phenotype of the d309 mutant is controlled by a single recessive gene. Compared to the B73 inbred line， the d309 mutant exhibited a significantly reduced plant height and shortened internodes. Cytological studies indicated that the cell length between the 5th and 6th internodes of the d309 mutant was significantly reduced. By constructing an F₂ population from the cross of d309 and PH6WC and employing BSR-seq technology， the mutation site was mapped to an interval of 3.47-17.47 Mb on chromosome 3. Further gene mapping localized the mutation site between two molecular markers， 5-4 and 5-7， within which there is only one open reading frame（Zm00001d039634） encoding gibberellin 3-oxidases （GA3ox）， which has been reported as Dwarf1. Sequencing results showed that the d309 mutant has a single nucleotide mutation in the CDS region of the Zm00001d039634 gene， leading to an amino acid sequence change. Protein structure prediction suggested that the mutation site is located within the Fe（II）2OGD （iron 2-oxoglutarate dioxygenase） domain. The dwarf phenotype of the d309 mutant was observed to be rescued upon exogenous application of gibberellins， thereby confirming d309 as a gibberellin biosynthesis-deficient mutant. Additionally， the d309 mutant differs from the reported Dwarf1 allelic mutants in its mutation mechanism， indicating that d309 is a new allelic variant of the Dwarf1 gene.

Abstract:Leaf color mutants are valuable tools for elucidating the mechanisms of chlorophyll biosynthesis and chloroplast development， and they play a significant role in understanding plant growth and development processes. In this study， green-leafed tomato material CR11A and yellow-leafed tomato material CH09-805 were used as parents to construct a genetic population to clarify the genetic rules of leaf color. Leaf chloroplast ultrastructure observation and chlorophyll content determination were performed on plants with different leaf colors. Furthermore， BSA-Seq and molecular marker screening were used for leaf color gene mapping and candidate gene analysis. The results showed that the F₁ plants had green leaves， and the F₂ population exhibited a segregation ratio of 12（green）∶3（yellow）∶1（golden）， indicating that tomato leaf color traits are controlled by two pairs of genes with dominant epistasis. Observation of chloroplast ultrastructure and determination of chlorophyll content revealed that the chloroplast ultrastructure of golden yellow leaves was severely damaged， and their chlorophyll content was significantly lower than that of pale yellow and green leaves. Using BSA-Seq and molecular marker screening， the tomato leaf color gene Sllc1 was mapped to a 114.53 kb physical distance on chromosome 7. The candidate interval included 13 annotated genes. Based on gene annotation information and expression identification， Solyc07g053630 and Solyc07g053640 were identified as candidate genes for Sllc1. This study identified candidate genes for tomato leaf color， providing important material and gene resources for elucidating the molecular mechanisms of tomato leaf color formation.

Abstract:Guava variants are abundant and fruit texture varies considerably between varieties. The softening degree of fruit determines its edible taste， transportation， storage and shelf life and other commodity values. In order to explore the regulatory genes affecting the texture softening of guava fruit， transcriptomic sequencing was performed on two cultivars，Fenhongmi（crisp）and Xigua No.2（soft）at the firm ripening stage and soft ripening stage. The results showed that the number of differentially expressed genes was the highest among two varieties at soft maturity stage. GO annotation showed that differentially expressed genes were mainly enriched in molecular functions such as binding activity and catalytic activity， and KEGG metabolic pathway analysis showed that differentially expressed genes were mainly enriched in photosynthesis， photosynthetic antenna protein， galactose metabolism and plant hormone signal transduction pathways. The difference of texture of the two varieties in soft ripening stage is closely related to the regulation of cell wall metabolism， lignin biosynthesis pathway， plant hormone metabolism genes and transcription factors. The up-regulated expression of J3R85008159_PG and J3R85010291_XTH is an important factor promoting the softening of guava. J3R85010291_TCH4 may regulate fruit softening by reducing the mechanical strength of cell wall. Down-regulated expression of lignin synthesis pathway genes （J3R8506005_CAD， J3R8502863_POD， J3R8507303_POD， J3R8500836_LAC and J3R8507803_LAC） delayed lignin accumulation and promoted fruit softening. ABA pathway regulatory genes （PYL and SnRK2）， ethylene pathway regulatory genes （ETR/ ERS， EBF1/2， EIN3） and related transcription factor family genes （J3R85017767_MYB、J3R85004770_MYB、J3R85004060_NAC、J3R85006932_NAC、J3R85012461_ERF 、J3R85010726_bHLH、J3R85003109_bHLH、J3R85014989_bHLH、J3R85015176_WRKY、J3R85014001_WRKY、J3R85014684_WRKY、J3R85010736_ WRKY） may synergistic regulate the expression of cell wall metabolic genes and thus affect the softening process of guava.

Abstract:Drought resistance is a complex quantitative trait of the interaction between crops and drought environment， accurate evaluation of drought resistance phenotype is the basis for mining drought resistance genes and exploring drought resistance genetics， it is very important for water-saving and drought-resistant rice breeding. The method system for the evaluation of drought resistance of rice germplasm during whole growth periods in the field has always been a technical problem concerned by drought-resistant breeding workers. Aims at this problem， we exploring and optimizing the conditions for assessing drought resistance based on many years of the evaluation and research of rice drought resistance in the field. The standard technical regulations for drought resistance evaluation in the field of rice germplasm during whole growth periods were summarized and normalized. It mainly includes general requirements， land preparation， the methods of planting， water management， fertilization， prevention of diseases， pests and weeds and drought resistance evaluation， so as to provide technical reference for drought resistance evaluation of rice germplasm during whole growth periods. The technical regulations are applicable to the evaluation of drought resistance during whole growth periods during the winter in Sanya city， Hainan province （from mid-November to early-April of the next year）.