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Abstract ［Objectives］ This study was conducted to provide technical standards for domestic Spathiphyllum variety description and resource evaluation.
［Methods］Through field trials and character surveys of the collected 83 Spathiphyllum varieties, after several revisions by fellow experts, and with reference to the Guidelines for Testing the Specificity, Consistency and Stability of New Plant Varieties: Spathiphyllum (TG/135/3) issued by the International Union For The Protection of New Varieties of Plants, the DUS testing guidelines for Spathiphyllum have been developed, and statistical analysis and other methods were used to study the traits for the guideline.
［Results］ Thirty two testing traits, including 11 mandatory traits, 8 basic traits, 10 new traits, and 3 optional traits were finally determined; five traits including plant height, plant width, and leaf length were divided into 7 grades, and 9 traits such as leaf width, spathe length, and spathe width were divided into 5 levels; and the observation method and trait code of the trait spathe depth were adjusted.
［Conclusions］The development of this guideline provides a basis for judging the specificity, consistency and stability of Spathiphyllum varieties, and is of great significance to the breeding and protection of Spathiphyllum varieties.
Key words Spathiphyllum Schott; Testing guideline; Characters; Evaluation
Received: May 27, 2021 Accepted: July 28, 2021
Peng ZHANG (1988-), male, P. R. China, assistant research fellow, devoted to research about DUS testing technology.
*Corresponding author.
Spathiphyllum Schott, also known as Baizhang, Baibaoyu, Baoyeyu, etc., is native to the Americas. It is a perennial herbaceous ornamental plant, as well as a familiar flower variety worldwide and one of the main flower varieties cultivated in China［1-2］. According to a survey on the consumption of potted flowers in Europe, more than 70% of consumers buy them to decorate their homes. Small-pot-diameter mini flowers are becoming more and more popular in the market. As early as 2010, sales in the Netherlands reached 19.90 million US dollars［3］. Spathiphyllum has unique flower posture, long flowering period, good tolerance to humidity, and wide adaptability. It has become an indoor ornamental plant which can be viewed and admired for flowers when there are flowers and for leaves when there are no flowers［4］. With the change of people’s aesthetic styles, the favorite Spathiphyllum varieties have changed from medium and large (plant height of 50-100 cm) to micro-small (plant height of 15-35 cm)［5］, which is in line with the low-carbon lifestyle advocated by people today. Therefore, the market demand is very large. In addition, it has the characteristics of short production cycle, fast turnover, high yield per unit area, low cultivation threshold, extensive habits, easy cultivation and maintenance, and southern provinces and large cities across China have successively propagated through tissue culture and multiplied seedlings. At present, the domestic production is mainly in Guangdong and Fujian, with an annual output of more than 90 million plants, and the domestic seedling quantity is as high as hundreds of millions. As the genus Spathiphyllum has not been included in China’s variety protection list so far, although many breeding companies have relatively mature varieties, they have not yet been circulated in the market, which is very unfavorable for the exchange of resources of Spathiphyllum varieties, breeding innovation and the development of the flower industry in China. Regarding the research of Spathiphyllum, a lot of research has been done on the Spathiphyllum from the aspects of photosynthesis, asexual reproduction, morphology, etc. In addition, there are also reports on tissue culture, plant growth regulator induction and hybrid breeding［7］. Liu et al.［8］ studied the photosynthetic characteristics and water use efficiency of five Spathiphyllum varieties, and showed that the instantaneous WUE of the Spathiphyllum varieties all reached the highest at 10:00, and watering between 8:00 and 10:00 could achieve the purpose of effective water use, which provides a basis for water management in the daily cultivation of Spathiphyllum. Liu et al.［9］ analyzed the genetic diversity of 23 samples of the genus Spathiphyllum using SRAP markers. According to the amplification results and the UPGMA clustering results, the 23 samples were divided into three groups, and the genetic diversity and genetic relationship of Spathiphyllum germplasms were analyzed at the molecular level, which provides a basis for the effective utilization and development of Spathiphyllum germplasm resources. However, there are no reports on the development of DUS testing guideline, character research, and variety evaluation of Spathiphyllum.
The guidelines for the testing of new plant varieties’ specificity, consistency and stability (DUS testing for short) are the technical and scientific basis for variety protection［10］. As early as 1990, the International Union For The Protection of New Varieties of Plants (UPOV) promulgated test guidelines for this species (TG/135/3)［11］, and Japan also promulgated corresponding test guidelines. Therefore, in order to protect the legal rights of breeders, improve the enthusiasm of breeding innovation, promote the process of breeding of Spathiphyllum and the development of Spathiphyllum industry, it is imperative to develop a Spathiphyllum DUS testing guideline suitable for China’s national conditions and with Chinese characteristics［12］. In December 2017, "Guideline for Testing the Specificity, Consistency and Stability of New Plant Varieties: Spathiphyllum", which was developed by Quality Standard and Testing Technology Research Institute, Yunnan Academy of Agricultural Sciences, was approved by experts from the Ministry of Agriculture. In this study, the traits of the collected species materials serving as the research object were screened, classified and evaluated for the Spathiphyllum testing guideline, hoping to provide a scientific basis for Spathiphyllum DUS testing technology. Materials and Methods
Material selection
The 83 Spathiphyllum varieties tested were all from Guangzhou Binfen Horticulture Co., Ltd., which began to be planted and managed in a unified manner in January 2016. According to the requirements of the UPOV technical document［13］, trait observation was carried out in a timely manner. The material information is shown in Table 1.
Experimental conditions
All materials were planted in the greenhouse of Shenwan Town, Guangzhou Zhongshan Binfen Horticulture Co., Ltd. The shading rate of the shading net was controlled at 65%-80%, and the air humidity was kept above 50%. The suitable temperature was 22-28 ℃. Specifically, the temperature was in the range of 25-30 ℃ from March to September and in the range of 18-22 ℃ from September to March of the second year, and the room temperature in winter was kept above 15 ℃. The cultivation medium was mainly peat, and flower pots were mainly 22 cm × 16 cm plastic basins. There were no less than 10 plants for each variety, with 2 repetitions. Other management measures were basically the same as the local conventional production of Spathiphyllum.
Data collection and analysis
Character selection and data collection were carried out in accordance with the requirements in the development of the UPOV technical document TGP/7 testing guideline. Quantitative traits were measured using a scale, and the visual traits were observed and corresponding data were collected strictly in accordance with the UPOV TG/135 /3 testing guideline.
Excel was used to calculate the minimum, maximum, average and standard deviation of 15 quantitative traits, and grade each quantitative trait according to the requirement that the grade difference was greater than or equal to 2 times the average standard deviation. Related parameters were calculated as follows: range=maximum-minimum, grade 1=range/(standard deviation mean×2); grade 2 was the smaller value of grade 1 according to 1, 3, 5, 7, 9; the grade difference was calculated according to grade difference=range/grade 2; and the grade number was the number of continuous different data distribution ranges determined according to the median and grade difference［14］. SPSS20.0 was used to analyze the correlation of the collected data.
Results and Analysis
Trait determination
The DUS testing guideline for Spathiphyllum finally determined the number of traits to be 32 (Table 2). The traits were mainly the mandatory traits required by the UPOV guideline TG 135/3 (trait with "*") in total, 11 in total, and 8 other basic traits, 10 new traits, 3 optional testing traits. The traits included 25 quantitative traits (QN), 4 qualitative traits (QL), and 3 pseudo-qualitative traits (PQ) by trait type. From the observation position, the characters involved in flowers were the most, followed by leaves, plants, and pedicels. Quantitative trait grading
Table 3 shows the minimum, maximum, standard deviation and average value of each of the 14 quantitative traits, including plants, leaves, pedicels, and buds of the 83 tested varieties. According to the requirement that the grade difference was greater than or equal to 2 times the average standard deviation, traits of the 83 varieties were divided into continuously distributed grading ranges. The 14 quantitative traits were divided into 5 and 7 grading ranges, including 5 traits such as plant height, plant width and leaf length which were divided into 7 grades and 9 traits such as leaf width, bud length and bud width which were divided into 5 grades (Table 4).
Correlation analysis between traits
By calculating the correlation coefficient between various quantitative traits, the results showed that except for trait 12 and trait 13, trait 2 and trait 18, trait 13 and trait 18, trait 4 and trait 24, and trait 12 and trait 24 which did not reach a significant level of correlation, the rest were all reached a significant correlation level (Table 5). Specifically, 95.89% among them reached a very significant correlation level, and the remaining 4.11% reached a significant correlation level. Except for a significant correlation with trait 4, trait 12, and trait 20, trait 30 (spathe depth) did not reach a significant level of correlation with other traits. In the guideline development process, it was relatively complicated to actually measure trait 30, and trait 30 was not a "*" trait in the UPOV testing guideline for this species (TG/135/3). Therefore, we considered changing the observation method of this trait from individual measurement (MS) to group observation (VG), and the trait code was changed into 1 (light), 2 (medium), and 3 (deep).
Conclusions and Discussion
Variety resources need to be increased
At present, the main varieties of Spathiphyllum in China are SP cody color, Spathiphyllum superpetite, SP sensation mini, SP vicki lynn, Huaye, SP queen, SP mojo, SP starlight, etc., most of which are large and medium-sized varieties introduced from abroad. Combined with changes in consumer demand and preferences at home and abroad, there is a lot of room for promotion in terms of leaf color, plant type, and tillering ability, and new varieties of resources will emerge in endlessly. As Spathiphyllum has not yet entered the agricultural plant variety protection list, it has a certain impact on domestic Spathiphyllum breeding, but the selection of more new varieties is the general trend. The introduction of foreign excellent varieties and intensified innovation of self-bred varieties can also speed up the promotion of the protection of Spathiphyllum varieties. Testing character adjustment and guideline revision
Compared with UPOV’s existing testing guideline, the testing guideline developed by China have added 9 traits such as "plant: size", "leaf: shape", "leaf: tip shape" and adjusted the expression status of 14 traits such as "plant: bud number", "leaf: length", and "leaf: width", based on the actual situation of China’s Spathiphyllum variety resources, which is more suitable for the status quo of China’s Spathiphyllum variety resources.
However, with the advancement of Spathiphyllum breeding work, it may be necessary to revise the existing guideline. The 32 basic traits selected in this guideline can currently distinguish the existing domestic Spathiphyllum varieties, but with the advancement of related work, it is not limited to this. In actual work, when there are indeed differences between a variety and other varieties, but only using the traits in the guideline is not enough to distinguish, we can use traits not listed in the guideline to describe, as long as the unlisted traits meet the requirements for traits in the relevant technical documents［15］. With the introduction of new varieties of Spathiphyllum, the basic traits or selected traits will be adjusted to meet the needs for differentiation and evaluation of more varieties. The increase and decrease of traits, the adjustment of expression status and the improvement of standard varieties are the key contents of the guideline revision［16］.
Effective evaluation of variety resources
Studies have shown that DUS testing traits can be applied to morphological diversity analysis［17］. There are many varieties of Spathiphyllum in China, and self-bred varieties are confused with foreign resources, which is not conducive to the preservation, classification and identification of Spathiphyllum and limit the hybrid breeding and production promotion of Spathiphyllum to a certain extent. According to the morphological traits involved in the developed Spathiphyllum DUS testing guideline, the varieties can be effectively distinguished and used for resource evaluation more effectively. The development of this testing guideline is of great significance in terms of variety breeding and variety protection.
References
［1］ ZHOU H, GUO H. Effect of heavy metal lead on physiological and biochemical indexes of Spathiphyllum kochii plants［J］. Subtropical Agriculture Research, 2017, 13(3): 177-182. (in Chinese)
［2］ HAN L, XIU JR, DAI Y, et al. Effect of several factors on shoots growth and proliferation of Spathiphyllum floribundum in bioreactor［J］. Journal of Agricultural Science Yanbian University, 2016, 38(4): 313-316. (in Chinese) ［3］ LI LB, ZHANG H, YE J, et al. Effects of salt stress on physiological characteristics and chlorophyll content of Spathiphyllum kochii［J］. Northern Horticulture, 2018(15): 103-108. (in Chinese)
［4］ ZHANG GF, REN GT, ZHOU ZP, et al. Optimization of chromosome sectioning and karyotype analysis of Spathiphyllum floribundum［J］. Pratacultural Science, 2017, 34(3): 532-538. (in Chinese)
［5］ CHEN HX, WAN XF, KANG YH, et al. The introduction of five varieties of Spathiphyllum［J］. Subtropical Plant Science, 2012, 41(2): 62-64. (in Chinese)
［6］ ZHANG GF, LIU J, LIU C, et al. Study on induction of somatic embryogenesis of inflorescence of Spathiphyllum［J］. Jiangsu Agricultural Sciences, 2017, 45(23): 38-41. (in Chinese)
［7］ CHEN SP. Large-scale production of Spathiphyllum［J］. China Flowers & Horticulture, 2017(6): 30-31. (in Chinese)
［8］ LIU XR, LIAO FX, WANG JX, et al. Photosynthetic character and water use efficiency in Spathiphyllum［J］. Acta Agriculturae Boreali-occidentalis Sinica, 2015, 24(2): 142-145. (in Chinese)
［9］ LIU XF, LIAO FX, LI DM, et al. Genetic relationship analysis and cultivar identification of Spathiphyllum using SRAP marker［J］. Guangdong Agricultural Sciences, 2017, 44(11): 26-31. (in Chinese)
［10］ CHU YX, DENG S, HUANG ZC, et al. Selection and classification for amaryllis (Hippeastrum) DUS testing quantitative traits［J］. Journal of Plant Genetic Resources, 2016, 17(3): 466-474. (in Chinese)
［11］ UPOV. TG/135 /3 Guidelines for the conduct of tests for distinctness, uniformity and stability Spathiphyllum (Spathiphyllum Schott)［S］. Geneva: UPOV, 1990.
［12］ LI HY, SHEN Q, WANG XS, et al. Test guideline of distinctness, uniformity and stability for eggplant variety［J］. Chinese Agricultural Science Bulletin, 2016, 32(31): 34-39. (in Chinese)
［13］ ZHANG XM, XU ZJ, LV B, et al. Associated document to the examination of distinctness, uniformity and stability and the general introduction to the descriptions of character (document TG/1/3)［M］. Beijing: China Agriculture Press, 2012: 1-114(in chinese).
［14］ CHU YX, DENG S, YANG XH, et al. Selection and assessment for Alstroemeria DUS testing traits［J］. Journal of Plant Genetic Resources, 2017, 18(3): 472-482. (in Chinese)
［15］ TANG H, LI RY, YANG XH. Associated document to the general introduction to the examination of distinctness, uniformity and stability and the development of harmonized descriptions of new varieties of plants (document TG/1/3)［M］. Beijing: China Agriculture Press, 2017: 1-214(in chinese).
［16］ New Plant Variety Testing Center of the Ministry of Agriculture, National Standardization Technical Committee for Testing New Varieties of Plants. TGP/7 Development of tset guidelines［M］. Beijing: China Agricultural Science and Technology Press, 2006: 11-19. (in Chinese)
［17］ LU BS, WANG RH, WANG FG, et al. Phenotypic diversity of maize inbred lines based on DUS testing traits［J］. Journal of Plant Genetic Resources, 2010, 11(1): 103-107. (in Chinese)
［Methods］Through field trials and character surveys of the collected 83 Spathiphyllum varieties, after several revisions by fellow experts, and with reference to the Guidelines for Testing the Specificity, Consistency and Stability of New Plant Varieties: Spathiphyllum (TG/135/3) issued by the International Union For The Protection of New Varieties of Plants, the DUS testing guidelines for Spathiphyllum have been developed, and statistical analysis and other methods were used to study the traits for the guideline.
［Results］ Thirty two testing traits, including 11 mandatory traits, 8 basic traits, 10 new traits, and 3 optional traits were finally determined; five traits including plant height, plant width, and leaf length were divided into 7 grades, and 9 traits such as leaf width, spathe length, and spathe width were divided into 5 levels; and the observation method and trait code of the trait spathe depth were adjusted.
［Conclusions］The development of this guideline provides a basis for judging the specificity, consistency and stability of Spathiphyllum varieties, and is of great significance to the breeding and protection of Spathiphyllum varieties.
Key words Spathiphyllum Schott; Testing guideline; Characters; Evaluation
Received: May 27, 2021 Accepted: July 28, 2021
Peng ZHANG (1988-), male, P. R. China, assistant research fellow, devoted to research about DUS testing technology.
*Corresponding author.
Spathiphyllum Schott, also known as Baizhang, Baibaoyu, Baoyeyu, etc., is native to the Americas. It is a perennial herbaceous ornamental plant, as well as a familiar flower variety worldwide and one of the main flower varieties cultivated in China［1-2］. According to a survey on the consumption of potted flowers in Europe, more than 70% of consumers buy them to decorate their homes. Small-pot-diameter mini flowers are becoming more and more popular in the market. As early as 2010, sales in the Netherlands reached 19.90 million US dollars［3］. Spathiphyllum has unique flower posture, long flowering period, good tolerance to humidity, and wide adaptability. It has become an indoor ornamental plant which can be viewed and admired for flowers when there are flowers and for leaves when there are no flowers［4］. With the change of people’s aesthetic styles, the favorite Spathiphyllum varieties have changed from medium and large (plant height of 50-100 cm) to micro-small (plant height of 15-35 cm)［5］, which is in line with the low-carbon lifestyle advocated by people today. Therefore, the market demand is very large. In addition, it has the characteristics of short production cycle, fast turnover, high yield per unit area, low cultivation threshold, extensive habits, easy cultivation and maintenance, and southern provinces and large cities across China have successively propagated through tissue culture and multiplied seedlings. At present, the domestic production is mainly in Guangdong and Fujian, with an annual output of more than 90 million plants, and the domestic seedling quantity is as high as hundreds of millions. As the genus Spathiphyllum has not been included in China’s variety protection list so far, although many breeding companies have relatively mature varieties, they have not yet been circulated in the market, which is very unfavorable for the exchange of resources of Spathiphyllum varieties, breeding innovation and the development of the flower industry in China. Regarding the research of Spathiphyllum, a lot of research has been done on the Spathiphyllum from the aspects of photosynthesis, asexual reproduction, morphology, etc. In addition, there are also reports on tissue culture, plant growth regulator induction and hybrid breeding［7］. Liu et al.［8］ studied the photosynthetic characteristics and water use efficiency of five Spathiphyllum varieties, and showed that the instantaneous WUE of the Spathiphyllum varieties all reached the highest at 10:00, and watering between 8:00 and 10:00 could achieve the purpose of effective water use, which provides a basis for water management in the daily cultivation of Spathiphyllum. Liu et al.［9］ analyzed the genetic diversity of 23 samples of the genus Spathiphyllum using SRAP markers. According to the amplification results and the UPGMA clustering results, the 23 samples were divided into three groups, and the genetic diversity and genetic relationship of Spathiphyllum germplasms were analyzed at the molecular level, which provides a basis for the effective utilization and development of Spathiphyllum germplasm resources. However, there are no reports on the development of DUS testing guideline, character research, and variety evaluation of Spathiphyllum.
The guidelines for the testing of new plant varieties’ specificity, consistency and stability (DUS testing for short) are the technical and scientific basis for variety protection［10］. As early as 1990, the International Union For The Protection of New Varieties of Plants (UPOV) promulgated test guidelines for this species (TG/135/3)［11］, and Japan also promulgated corresponding test guidelines. Therefore, in order to protect the legal rights of breeders, improve the enthusiasm of breeding innovation, promote the process of breeding of Spathiphyllum and the development of Spathiphyllum industry, it is imperative to develop a Spathiphyllum DUS testing guideline suitable for China’s national conditions and with Chinese characteristics［12］. In December 2017, "Guideline for Testing the Specificity, Consistency and Stability of New Plant Varieties: Spathiphyllum", which was developed by Quality Standard and Testing Technology Research Institute, Yunnan Academy of Agricultural Sciences, was approved by experts from the Ministry of Agriculture. In this study, the traits of the collected species materials serving as the research object were screened, classified and evaluated for the Spathiphyllum testing guideline, hoping to provide a scientific basis for Spathiphyllum DUS testing technology. Materials and Methods
Material selection
The 83 Spathiphyllum varieties tested were all from Guangzhou Binfen Horticulture Co., Ltd., which began to be planted and managed in a unified manner in January 2016. According to the requirements of the UPOV technical document［13］, trait observation was carried out in a timely manner. The material information is shown in Table 1.
Experimental conditions
All materials were planted in the greenhouse of Shenwan Town, Guangzhou Zhongshan Binfen Horticulture Co., Ltd. The shading rate of the shading net was controlled at 65%-80%, and the air humidity was kept above 50%. The suitable temperature was 22-28 ℃. Specifically, the temperature was in the range of 25-30 ℃ from March to September and in the range of 18-22 ℃ from September to March of the second year, and the room temperature in winter was kept above 15 ℃. The cultivation medium was mainly peat, and flower pots were mainly 22 cm × 16 cm plastic basins. There were no less than 10 plants for each variety, with 2 repetitions. Other management measures were basically the same as the local conventional production of Spathiphyllum.
Data collection and analysis
Character selection and data collection were carried out in accordance with the requirements in the development of the UPOV technical document TGP/7 testing guideline. Quantitative traits were measured using a scale, and the visual traits were observed and corresponding data were collected strictly in accordance with the UPOV TG/135 /3 testing guideline.
Excel was used to calculate the minimum, maximum, average and standard deviation of 15 quantitative traits, and grade each quantitative trait according to the requirement that the grade difference was greater than or equal to 2 times the average standard deviation. Related parameters were calculated as follows: range=maximum-minimum, grade 1=range/(standard deviation mean×2); grade 2 was the smaller value of grade 1 according to 1, 3, 5, 7, 9; the grade difference was calculated according to grade difference=range/grade 2; and the grade number was the number of continuous different data distribution ranges determined according to the median and grade difference［14］. SPSS20.0 was used to analyze the correlation of the collected data.
Results and Analysis
Trait determination
The DUS testing guideline for Spathiphyllum finally determined the number of traits to be 32 (Table 2). The traits were mainly the mandatory traits required by the UPOV guideline TG 135/3 (trait with "*") in total, 11 in total, and 8 other basic traits, 10 new traits, 3 optional testing traits. The traits included 25 quantitative traits (QN), 4 qualitative traits (QL), and 3 pseudo-qualitative traits (PQ) by trait type. From the observation position, the characters involved in flowers were the most, followed by leaves, plants, and pedicels. Quantitative trait grading
Table 3 shows the minimum, maximum, standard deviation and average value of each of the 14 quantitative traits, including plants, leaves, pedicels, and buds of the 83 tested varieties. According to the requirement that the grade difference was greater than or equal to 2 times the average standard deviation, traits of the 83 varieties were divided into continuously distributed grading ranges. The 14 quantitative traits were divided into 5 and 7 grading ranges, including 5 traits such as plant height, plant width and leaf length which were divided into 7 grades and 9 traits such as leaf width, bud length and bud width which were divided into 5 grades (Table 4).
Correlation analysis between traits
By calculating the correlation coefficient between various quantitative traits, the results showed that except for trait 12 and trait 13, trait 2 and trait 18, trait 13 and trait 18, trait 4 and trait 24, and trait 12 and trait 24 which did not reach a significant level of correlation, the rest were all reached a significant correlation level (Table 5). Specifically, 95.89% among them reached a very significant correlation level, and the remaining 4.11% reached a significant correlation level. Except for a significant correlation with trait 4, trait 12, and trait 20, trait 30 (spathe depth) did not reach a significant level of correlation with other traits. In the guideline development process, it was relatively complicated to actually measure trait 30, and trait 30 was not a "*" trait in the UPOV testing guideline for this species (TG/135/3). Therefore, we considered changing the observation method of this trait from individual measurement (MS) to group observation (VG), and the trait code was changed into 1 (light), 2 (medium), and 3 (deep).
Conclusions and Discussion
Variety resources need to be increased
At present, the main varieties of Spathiphyllum in China are SP cody color, Spathiphyllum superpetite, SP sensation mini, SP vicki lynn, Huaye, SP queen, SP mojo, SP starlight, etc., most of which are large and medium-sized varieties introduced from abroad. Combined with changes in consumer demand and preferences at home and abroad, there is a lot of room for promotion in terms of leaf color, plant type, and tillering ability, and new varieties of resources will emerge in endlessly. As Spathiphyllum has not yet entered the agricultural plant variety protection list, it has a certain impact on domestic Spathiphyllum breeding, but the selection of more new varieties is the general trend. The introduction of foreign excellent varieties and intensified innovation of self-bred varieties can also speed up the promotion of the protection of Spathiphyllum varieties. Testing character adjustment and guideline revision
Compared with UPOV’s existing testing guideline, the testing guideline developed by China have added 9 traits such as "plant: size", "leaf: shape", "leaf: tip shape" and adjusted the expression status of 14 traits such as "plant: bud number", "leaf: length", and "leaf: width", based on the actual situation of China’s Spathiphyllum variety resources, which is more suitable for the status quo of China’s Spathiphyllum variety resources.
However, with the advancement of Spathiphyllum breeding work, it may be necessary to revise the existing guideline. The 32 basic traits selected in this guideline can currently distinguish the existing domestic Spathiphyllum varieties, but with the advancement of related work, it is not limited to this. In actual work, when there are indeed differences between a variety and other varieties, but only using the traits in the guideline is not enough to distinguish, we can use traits not listed in the guideline to describe, as long as the unlisted traits meet the requirements for traits in the relevant technical documents［15］. With the introduction of new varieties of Spathiphyllum, the basic traits or selected traits will be adjusted to meet the needs for differentiation and evaluation of more varieties. The increase and decrease of traits, the adjustment of expression status and the improvement of standard varieties are the key contents of the guideline revision［16］.
Effective evaluation of variety resources
Studies have shown that DUS testing traits can be applied to morphological diversity analysis［17］. There are many varieties of Spathiphyllum in China, and self-bred varieties are confused with foreign resources, which is not conducive to the preservation, classification and identification of Spathiphyllum and limit the hybrid breeding and production promotion of Spathiphyllum to a certain extent. According to the morphological traits involved in the developed Spathiphyllum DUS testing guideline, the varieties can be effectively distinguished and used for resource evaluation more effectively. The development of this testing guideline is of great significance in terms of variety breeding and variety protection.
References
［1］ ZHOU H, GUO H. Effect of heavy metal lead on physiological and biochemical indexes of Spathiphyllum kochii plants［J］. Subtropical Agriculture Research, 2017, 13(3): 177-182. (in Chinese)
［2］ HAN L, XIU JR, DAI Y, et al. Effect of several factors on shoots growth and proliferation of Spathiphyllum floribundum in bioreactor［J］. Journal of Agricultural Science Yanbian University, 2016, 38(4): 313-316. (in Chinese) ［3］ LI LB, ZHANG H, YE J, et al. Effects of salt stress on physiological characteristics and chlorophyll content of Spathiphyllum kochii［J］. Northern Horticulture, 2018(15): 103-108. (in Chinese)
［4］ ZHANG GF, REN GT, ZHOU ZP, et al. Optimization of chromosome sectioning and karyotype analysis of Spathiphyllum floribundum［J］. Pratacultural Science, 2017, 34(3): 532-538. (in Chinese)
［5］ CHEN HX, WAN XF, KANG YH, et al. The introduction of five varieties of Spathiphyllum［J］. Subtropical Plant Science, 2012, 41(2): 62-64. (in Chinese)
［6］ ZHANG GF, LIU J, LIU C, et al. Study on induction of somatic embryogenesis of inflorescence of Spathiphyllum［J］. Jiangsu Agricultural Sciences, 2017, 45(23): 38-41. (in Chinese)
［7］ CHEN SP. Large-scale production of Spathiphyllum［J］. China Flowers & Horticulture, 2017(6): 30-31. (in Chinese)
［8］ LIU XR, LIAO FX, WANG JX, et al. Photosynthetic character and water use efficiency in Spathiphyllum［J］. Acta Agriculturae Boreali-occidentalis Sinica, 2015, 24(2): 142-145. (in Chinese)
［9］ LIU XF, LIAO FX, LI DM, et al. Genetic relationship analysis and cultivar identification of Spathiphyllum using SRAP marker［J］. Guangdong Agricultural Sciences, 2017, 44(11): 26-31. (in Chinese)
［10］ CHU YX, DENG S, HUANG ZC, et al. Selection and classification for amaryllis (Hippeastrum) DUS testing quantitative traits［J］. Journal of Plant Genetic Resources, 2016, 17(3): 466-474. (in Chinese)
［11］ UPOV. TG/135 /3 Guidelines for the conduct of tests for distinctness, uniformity and stability Spathiphyllum (Spathiphyllum Schott)［S］. Geneva: UPOV, 1990.
［12］ LI HY, SHEN Q, WANG XS, et al. Test guideline of distinctness, uniformity and stability for eggplant variety［J］. Chinese Agricultural Science Bulletin, 2016, 32(31): 34-39. (in Chinese)
［13］ ZHANG XM, XU ZJ, LV B, et al. Associated document to the examination of distinctness, uniformity and stability and the general introduction to the descriptions of character (document TG/1/3)［M］. Beijing: China Agriculture Press, 2012: 1-114(in chinese).
［14］ CHU YX, DENG S, YANG XH, et al. Selection and assessment for Alstroemeria DUS testing traits［J］. Journal of Plant Genetic Resources, 2017, 18(3): 472-482. (in Chinese)
［15］ TANG H, LI RY, YANG XH. Associated document to the general introduction to the examination of distinctness, uniformity and stability and the development of harmonized descriptions of new varieties of plants (document TG/1/3)［M］. Beijing: China Agriculture Press, 2017: 1-214(in chinese).
［16］ New Plant Variety Testing Center of the Ministry of Agriculture, National Standardization Technical Committee for Testing New Varieties of Plants. TGP/7 Development of tset guidelines［M］. Beijing: China Agricultural Science and Technology Press, 2006: 11-19. (in Chinese)
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