Subordinate Function Values Research Articles

Analyzing cold hardiness (Based on DTA) of one-year-old branches of peaches.

In this study, we conducted a low-temperature exothermic (LTE) investigation on 1-year-old (1a) branches of sixteen peach cultivars through a differential thermal analysis (DTA) procedure. We used a three-point approach to determine the lethal injury temperature (LT-I) of the xylem, the LTE correlation indexes, and the subordinate function value method were applied to compare cold hardiness of sixteen peach varieties. The results showed that the slope of the LT-I for the xylem of sixteen peach cultivars was different, and the LTE indexes were significantly different. Among all the studied varieties, the cold hardiness was strongest in Donghe No.1, followed by Wangjiazhuangmaotao No.2 and Hunchun. Qiuyan and Yanhong are second, and belong to the cold-resistant type; Qiuyi, Okubo, Zhongnongjinhui, and Chunmei, exhibited medium cold hardiness. Zhongtaohongyu, Spring snow, Yufei, and Zhongyou No.8 varieties exhibited low hardiness; while the 21st century, Golden Honey No. 1 and Zhonghuashoutao have the worst cold hardiness and are the weakest cold-hardiness types. In addition, the injury degrees of xylem from LT-I analysis were significantly related to the browning rates (BR) and electrolytic leakage (EI) from traditional low temperature freezing analysis. It is demonstrated that the LTE analysis is a simple, accurate, and practical method for identifying the cold hardiness of 1a branches of peach.

Foliar Application of Chitosan (CTS), γ-Aminobutyric Acid (GABA), or Sodium Chloride (NaCl) Mitigates Summer Bentgrass Decline in the Subtropical Zone.

Creeping bentgrass (Agrostis stolonifera) is an excellent cool-season turfgrass that is widely used in urban gardening, landscaping, and golf turf. Triennial field experiments from 2017 to 2019 were conducted to investigate effects of the foliar application of chitosan (CTS), γ-aminobutyric acid (GABA), or sodium chloride (NaCl) on mitigating summer bentgrass decline (SBD) and exploring the CTS, GABA, or NaCl regulatory mechanism of tolerance to summer heat stress associated with changes in chlorophyll (Chl) loss and photosynthetic capacity, osmotic adjustment (OA), oxidative damage, and cell membrane stability. The findings demonstrated that persistent ambient high temperatures above 30 °C during the summer months of 2017, 2018, and 2019 significantly reduced the turf quality (TQ), Chl content, photochemical efficiency of PSII (Fv/Fm and PIABS), leaf relative water content, and osmotic potential (OP) but significantly increased electrolyte leakage (EL) and the accumulations of free proline, water-soluble carbohydrate (WSC), hydrogen peroxide (H2O2), and malondialdehyde (MDA). The foliar application of CTS, GABA, or NaCl could significantly alleviate SBD, as reflected by improved TQ and delayed Chl loss during hot summer months. Heat-induced declines in Fv/Fm, PIABS, the net photosynthetic rate (Pn), the transpiration rate (Tr), and water use efficiency (WUE) could be significantly mitigated by the exogenous application of CTS, GABA, or NaCl. In addition, the foliar application of CTS, GABA, or NaCl also significantly improved the accumulations of free proline and WSC but reduced the EL, OP, and H2O2 content and the MDA content in leaves of creeping bentgrass in favor of water and redox homeostasis in summer. Based on the comprehensive evaluation of the subordinate function value analysis (SFVA), the CTS had the best effect on the mitigation of SBD, followed by GABA and NaCl in 2017, 2018, and 2019. The current study indicates that the foliar application of an appropriate dose of GABA, CTS, or NaCl provides a cost-effective strategy for mitigating SBD.

Effects of fertilization gradient on the production performance and nutritional quality of cultivated grasslands in karst areas.

Optimal fertilization is an important measure for managing cultivated grasslands, and a necessary means for maintaining the nutrient balance, yield, and quality of grassland ecosystems. This study aimed to explore the effects of organic fertilizers on the production performance and nutritional quality of cultivated grasslands in karst areas. Two types of monocultured cultivated grasslands (i.e., Medicago sativa and Dactylis glomerata) were employed as the research objects, and a randomized block design was adopted to investigate the effects of five fertilization gradients on the forage height, coverage, yield, and nutritional quality of the cultivated grasslands. According to the results, the plant height, coverage, and yield of M. sativa first presented an increasing trend, then decreased with increasing fertilization gradient, with a peak at 20-30 t/hm2 fertilization gradient. The height, coverage, and yield of D. glomerata increased gradually with increase in fertilization gradient, and peaked at 40 t/hm2. Meanwhile, the crude protein (CP) and ether extract (EE) contents of both grassland types displayed first presented an increasing trend, then decreased with increasing fertilization gradient, and peaked at 10-30 t/hm2 fertilization gradient. The neutral detergent fiber (NDF) and acidic detergent fiber (ADF) contents of M. sativa presented "N-shaped" and "M-shaped" change trends with increasing fertilization gradient, while those of D. glomerata showed "V-shaped" and "M-shaped" change trends, reaching minimum values under fertilization gradients of 30 and 20 t/hm2, respectively. Year, fertilization, and year × fertilization (Y×F) significantly affected the plant heights, coverages, dry/fresh weight ratios, and yields of M. sativa and D. glomerata. The contribution of coverage to the subordinate function of M. sativa was greatest at a fertilization gradient of 20 t/hm2. Meanwhile, the subordinate function values of the height and coverage of D. glomerata increased gradually with increasing fertilization gradient, but the difference in the subordinate function value of height was only 0.09%-0.18% under the fertilization gradient of 20-40 t/hm2. Evaluation of forage nutrition revealed 10-30 t/hm2 and 20-30 t/hm2 as the optimal organic fertilizer application rates for M. sativa and D. glomerata, respectively.

Impact of summer heat stress inducing physiological and biochemical responses in herbaceous peony cultivars (Paeonia lactiflora Pall.) from different latitudes

As global temperatures continue to rise, heat stress and its severity are projected to advance as a major abiotic stress, seriously limiting the growth and production of herbaceous peony (Paeonia lactiflora Pall.), especially in low-latitude areas. Therefore, determining the ravaging effects of heat stress on the growth and development of herbaceous peony has become a prerequisite for expanding the cultivation area of this world-renowned ornamental crop. Comprehensive research on physiological and biochemical responses to summer heat stress was conducted between low-latitude and midlatitude herbaceous peony cultivars at low latitudes. Field observations showed that the stay-green (SG) duration varied among the cultivars from different latitudes and had a direct correlation with the level of heat damage. As the heat stress intensified, chlorophyll (Chl) contents and Chl fluorescence were decreased in the six cultivars. On the contrary, the relative electrical conductivity (REC) increased sharply, with the low-latitude ‘Hang Baishao’ presenting the lowest REC among the six cultivars before August 15 (with the highest temperatures). Photosynthetic curves showed more sustained photosynthesis in ‘Hang Baishao’, ‘Meiju’ and ‘Bo Baishao’. Based on principal component analysis (PCA) and subordinate function value analysis, ‘Hang Baishao’ was deduced as the most heat-tolerant cultivar, whereas ‘Zhuguang’ as a most heat-sensitive cultivar out of the six cultivars. The oxidative stress analysis between the two cultivars indicated an over-accumulation of reactive oxygen species (ROS) and malondialdehyde (MDA) with lower antioxidant enzyme activity in ‘Zhuguang’ than ‘Hang Baishao’. The results imply that heat-tolerant ‘Hang Baisao’ exhibited minimal heat damage and a delayed SG duration based on its enhanced antioxidant enzyme activity and heat acclimation under high-temperature stress. This study could provide insights into the responses and adaptions of peonies to heat stress and aid in the breeding of excellent peonies with improved heat resistance under ever-changing climatic conditions.

Evaluation of genetic diversity and drought tolerance among thirty-three dichondra (<i>Dichondra repens</i>) genotypes

Dichondra (<italic>Dichondra repens</italic>) is an important ground cover plants and is also used as an herbal medicine in China. Objectives of this study were to evaluate phenotypic and genetic diversities among 33 genotypes by using 18 simple sequence repeat (SSR) markers and to further identify the drought tolerance of these germplasms based on five physiological parameters. Results showed that natural variations in phenotypes including plant height, leaf area, leaf thickness, and petiole length were observed among 33 genotypes under well-watered condition. All 18 SSR primer pairs were found to be polymorphic and significant genetic variation was found in these genotypes. In addition, there were obvious differences in leaf relative water content (RWC), electrolyte leakage (EL), chlorophyll (Chl) content, photochemical efficiency (Fv/Fm), and performance index on absorption basis (PI_ABS) among 33 genotypes in response to a prolonged period of drought stress (46 days). Drought tolerance of 33 genotypes was then ranked by using subordinate function value analysis (SFVA) and the most drought-tolerant or -sensitive genotypes were identified as Dr5 or Dr29, respectively. Principal component analysis (PCA) further classified 33 genotypes into group I (drought-tolerant), group II (drought-sensitive), and group III (medium types). Current findings showed that 18 selected SSR primers could be potentially used to analyze genetic diversity and varietal identification in dichondra species. Drought-tolerant wild dichondra resources provide a rich genetic base for breeding of new cultivars.

Dynamics of Spring Regrowth and Comparative Production Performance of 50 Autumn-Sown Alfalfa Cultivars in the Coastal Saline Soil of North China.

Alfalfa (Medicago sativa L.) production is affected by many factors, including management practices, soil conditions, and the environmental elements of the target area. Varietal differences, in terms of agronomic performance and forage yield, among 50 alfalfa cultivars under six harvest systems following regrowth were evaluated during the growing season of 2019–2020 under non-irrigated rainfed conditions in a coastal saline-alkali soil region of North China. Days to harvesting, plant height, canopy area, growth rate, and forage yield were assessed to rank the cultivars. Furthermore, the key factor influencing the regrowth of the second year after over-wintering was identified based on the growth status before over-wintering by using the Boston Matrix method. Results showed significant (p < 0.05) differences among cultivars and harvests regarding plant height, canopy area, and forage yield. Alfalfa forage yield ranged between 24.2 t ha−1 yr−1 and 32.7 t ha−1 yr−1. The highest forage yield was obtained in cultivar Guochan No.1, and was lowest in cultivar Magnum 601. Forage yield reached the greatest values for the first harvest, and then decreased gradually and changed stably. The forage yield of the third, fourth, fifth, and sixth harvest ranged from 3.4 t ha−1 to 4.3 t ha−1 (averaged across 50 cultivars), which represented 10.8% to 15.2% of the annual total forage production. We also observed that forage yield correlated strongly, but negatively, with the growth rate. According to subordinate function value analysis, Womu No.1, WL440HQ, Weston, Surprise, and WL354HQ proved optimum cultivars for general cultivation in this coastal area. In future, development of alfalfa cultivars with improved regrowth and tolerance to heavy saline-alkali soil and early spring drought would be necessary to increase forage yield under rainfed conditions in coastal saline-alkali areas of North China.

Stand Stability of Pure and Mixed-Eucalyptus Forests of Different Tree Species in a Typhoon-Prone Area

Background and Objectives: The stable stand structure of mixed plantations is the basis of giving full play to forest ecological function and benefit. However, the monocultural Eucalyptus plantations with large-scale and successive planting that caused ecological problems such as reduced species diversity and loss of soil nutrients have presented to be unstable and vulnerable, especially in typhoon-prone areas. The objective of this study was to evaluate the nonspatial structure difference and the stand stability of pure and mixed-Eucalyptus forests, to find out the best mixed pattern of Eucalyptus forests with the most stability in typhoon-prone areas. Materials and Methods: In this study, we randomly investigated eight plots of 30 m × 30 m in pure and mixed-Eucalyptus (Eucalyptus urophylla S. T. Blake × E. grandis W. Hill) plantations of different tree species (Neolamarckia cadamba (Roxb.) Bosser, Acacia mangium Willd., and Pinus elliottii var. Elliottii Engelm. × P. caribaea Morelet) on growth status, characterized and compared the distribution of nonspatial structure of the monoculture and mixtures, and evaluated the stand quality and stability from eight indexes of the nonspatial structure, including preservation rate, stand density, height, diameter, stem form, degree of stem inclination, tree-species composition, and age structure. Results: Eucalyptus surviving in the mixed plantation of Eucalyptus and A. mangium (EA) and in the mixed plantation of Eucalyptus and P. elliottii × P. caribaea (EP) were 5.0% and 7.6% greater than those in pure Eucalyptus plantation (EE), respectively, while only the stand preservation rate of EA was greater (+2.9%) than that of the pure Eucalyptus plantation. The proportions of all mixtures in the height class greater than 7 m were fewer than that of EE. The proportions of EA and mixed plantation of Eucalyptus and N. cadamba (EN) in the diameter class greater than 7 m were 10.6% and 7.8%, respectively, more than that of EE. EN had the highest ratio of branching visibly (41.0%), EA had the highest ratio of inclined stems (8.1%), and EP had the most straight and complete stem form (68.7%). The stand stability of the mixed plantation of Eucalyptus and A. mangium presented to be optimal, as its subordinate function value (0.76) and state value (ω = 0.61) of real stand were the largest. Conclusions: A. mangium is a superior tree species to mix with Eucalyptus for a more stable stand structure in the early growth stage to approach an evident and immense stability and resistance, which is of great significance for the forest restoration of Eucalyptus in response to extreme climate and forest management.

Identification of cold resistance and resistance physiological response of eggplant germplasms for rootstock

[Objective] The purpose of this study is to explore the effects of low temperature on the physiology of eggplant seedlings for rootstock, select the germplasms with strong cold resistance, and to provide a reference for the breeding of cold tolerant rootstocks suitable for grafting cultivation of autumn and winter tomato in South China. [Method] Sixteen eggplant germplasms for rootstock were used as materials, and the low temperature treatment temperatures of 10, 15 and 20 °C were set. The cold tolerance of eggplant germplasms for rootstock was evaluated according to germination index, chilling injury index and physiological index in the germonation and old temperature stress experiment. [Result] The low temperature of 10 °C significantly inhibited the germination of eggplant seeds for rootstock, and the germination rates were all less than 10.00% except that germination rate of J61 was 18.33%. There was no significant correlation among seed germination rate, germination index, germination potential and seedling chilling injury index ( P>0.05). The seedling chilling injury indexes of germplasm BC05 and J13 were 0.16, 0.20 respectively, showing high resistance (HR) to low temperature. The seedling chilling injury indexes of germplasm BC06, J60, AQ and A were 0.27-0.40, which showed moderate resistance (MR) to low temperature. The chilling injury index of 8 germplasms such as BC01, BC02 and BC03 ranged from 0.40-0.56, which showed resistance (R) to low temperature. Under low temperature stress at 10 °C, the chlorophyll content of the tested germplasm seedlings decreased, while the conductivity, malondialdehyde (MDA) and proline(Pro) contents increased, and the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) increased, but the response degree of different germplasms were different. The chilling injury index of seedlings was extremely significantly ( P<0.01, the same below) or significantly ( P<0.05, the same below) positively correlated with the change rate of chlorophyll content and MDA content. It was significantly or extremely significantly negatively correlated with the change rate of Pro content, activities of SOD, POD and CAT, respectively. The subordinate function value of the low temperature resistance of the tested germplasms were analyzed. The above six germplasm with HR and MR were ranked in the top six for their comprehensive low temperature resistance. And the above six germplasms were classified as high resistance to low temperature or resistance to low temperature by cluster analysis. [Conclusion] The index of seed germination should not be used as the identification index of cold tolerance of eggplant for rootstock. The seedlings chilling injury index, chlorophyll, MDA and Pro contents, SOD, POD and CAT activities can be used as the identification indexes of cold tolerance. The results of comprehensive evaluation show that BC05, J13, BC06, J60, AQ and A have high resistance to low temperature. And above six gemplasms can be used as backbone germplasm materials for breeding new varieties of cold-tolerant rootstocks. 摘要 【目的】 探讨低温对砧用茄子幼苗生理的影响, 筛选出耐冷性强的种质, 为选育适合华南地区秋冬番茄嫁 接栽培的耐冷砧木提供参考依据。 【方法】 以16份砧用茄子种质为材料, 设置10、15和20 °C不同低温处理, 通过种子发 芽及幼苗低温胁迫试验, 根据发芽指标、冷害指数和生理指标鉴定评价砧用茄子种质的耐冷性。 【结果】10 °C低温明 显抑制砧用茄子种子萌发, 除J61的发芽率为18.33%外其余种质的发芽率均在10.00%以下, 种子发芽率、发芽指数、发芽势与幼苗冷害指数均无显著相关性 ( P>0.05)。种质BC05和J13的幼苗冷害指数分别为0.16和0.20,表现强耐低 温, 种质BC06、J60、AQ和A的幼苗冷害指数为0.27~0.40,表现中耐低温, BC01、BC02和BC03等8份种质的冷害指数为 0.40~0.56,表现耐低温。10 °C低温胁迫下, 幼苗叶绿素含量降低, 电导率、内'二醛(MDA)和脯氨酸(Pro)含量增高, 超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性增加, 不同种质的响应程度不同。幼苗冷害指 数分别与叶绿素含量、MDA含量的变化率呈极显著 ( P<0.01, 下同) 和显著 ( P<0.05,下同) 正相关, 与Pro含量及SOD、POD、CAT活性的变化率呈显著或极显著负相关。对供试种质的耐冷性进行隶属函数综合分析, 以上表现强耐低温、中耐低温的6份种质的综合耐冷性排序前6, 聚类分析将这6份种质归类为强耐低温类、耐低温类。 【结论】 种子发芽指 标不应作为砧用茄子耐冷性的鉴定指标, 幼苗冷害指数及叶绿素、MDA、Pro含量和SOD、POD、CAT活性6项生理指 标可作为耐冷性的鉴定指标。综合评价结果, BC05, J13, BC06, J60, AQ和A等6份种质耐冷性强, 可作为选育耐冷砧 木新品种的骨十种质材料加以利用。

Estimation of Regional Effect, Evaluation Index and Subordinate Function of Mulberry Silkworm in Some Egyptian Governorates

Two local and important hybrids of silkworm, Bombyx mori L. were reared in three Egyptian governorates of Qalubyia, Giza and Sohag (Q, G and S). Fourteen parameters of 5th instar duration (FD), whole larvae duration (LD), mortality percentage (MP), number of cocoon/liter (C /L), cocooning percentage (CP), duple cocooning percentage (DCP), cocoon crop by number (Crop/N), cocoon crop by weight (Crop/W) were recorded. Cocoon weight (CW), cocoon shell weight (CSW), pupae weight (PW), cocoon shell ratio (CSR), silk productivity (SP) for females and males were investigated. The results revealed that rearing silkworm was better in Qalubyia and Giza comparing with Sohag governorate. Some modifications for adjusting the rearing techniques, temperature and humidity to raise the silk production were recommended. As well as selections the hybrids suitable for Upper Egypt conditions. Performances of hybrids characters are changed according to the environment changed. The average of CW, CSW, PW, CSR and SP traits were better for both sexes in Qalubyia governorate. Hybrid of hy1 was the best for CW, CSW, PW, CSR and SP traits for both sexes. Both of hy1 and hy2 were mostly the best hybrids in Qalubyia, Giza and Sohag of females and males. Evaluation index and subordinate function values depended on the hybrids which represented the genetic factor and the locations that represented the environmental factor and its interactions.

Heterosis Evaluation of Some Local and Imported Hybrids of Silkworm, Bombyx mori L.

Five local and two imported hybrids were used. The hybrids were evaluated according to heterosis over mid, better and check parent value. As well as evaluation index and subordinate function value for cocoon weight (CW), cocoon shell weight (CSW), pupal weight (PW), cocoon shell ratio (CSR), silk productivity (SP) for females and males. fifth instar duration (Fd), total larval duration (LD), mortality percentage (MP), number of cocoon per liter (C/L), cocooning percentage (CP), pupation ratio (PR), cocoon crop by number (crop/No) and weight (Crop/W), fecundity (Fecund) and fertility (Fertili). There isn't any hybrid earned the best heterosis over mid parent and better parent value for all traits together. HY A hybrid has the best heterosis for most characters understudy over mid and better parent values. Generally, HY A exhibited hybrid vigour over check parent value of G1 and G2 of most characters under study. Hybrid HY A has the best results for most traits under investigation. About the mean of evaluation index for hybrids understudy, best data registered for HY A, HY B, G2 and G1. Also, hybrid HY A registered the highest value of the subordinate function for most traits. Cumulative subordinate function raveled that G2, HY A, G1 and HY B hybrids acquired the highest results, respectively.

Drought resistance identification and drought resistance indexes screening of barley resources at mature period

Drought is one of the major factors affecting barley production. Identification of drought resistance of barley resource at maturity stage, could provide and their associating indexes a basis for breeding drought-resistant cultivars. Field experiments were carried out in Wuwei city, Gansu province, in 2016 and 2017, where the average rainfall during the main water requirement period is less than 40 mm. thirty barley resource under measured normal irrigation and drought stress were used to measured plant height, spike length, tiller number, grain number per plant, grain weight per plant, grain number per spike, 1000-grain weight and yield of barley. Drought resistance comprehensive evaluation value ( D -value), comprehensive drought resistance coefficient (CDC-value), weight drought resistance coefficient (WDC-value), correlation analysis, frequency analysis, principal component analysis, grey relational analysis, subordinate function analysis, clustering analysis, and stepwise regression analysis were combined to identify the drought resistance and to screen drought resistance indexes of tested resource at mature period. Drought stress had significant effects on all measured indexes. Frequency analysis showed that the sensitivity of each index to drought stress was yield, plant height, grain weight per plant, spike length, grain number per plant, tiller number, grain number per spike and 1000-grain weight. The yield was very significantly and positively correlated with plant height, spike length, tiller number, grain number per plant and grain weight per plant, and significantly and positively correlated with grain number per spike, but not correlated with 1000-grain weight. Principal component analysis showed that five principal components could represent 86.39% of the original data information of barley drought resistance. The ranks of drought resistance based on the D -value, CDC-value, and WDC-value were similar. Grey relational analysis showed that the correlation degree between DC-value of all indexes and D -value in turn for yield, grain weight per plant, grain number per plant, spike length, plant height, tiller number, grain number per spike and 1000-grain weight, the correlation degree between DC-value of all indexes and WDC-value in turn for grain weight per plant, yield, grain number per plant, tiller number, spike length, grain number per spike, plant height and1000-grain weight, According to D -value clustering analysis, tested barley materials were divided into five drought resistance grades, in which five were in grade 1, one was in grade 2, eleven were in grade 3, ten were in grade 4, and three were in grade 5. Except for tiller number and 1000-grain weight, the subordinate function values, CDC-values, D -values, and WDC-values of other indicators were increased with increase of drought resistance grades. Stepwise regression analysis showed that plant height, Spike length, tiller number, grain number per plant, grain weight per plant, grain number per spike, 1000-grain weight and yield were closely related to the D -value. Drought stress had significant effects on all indexes of barley resources at mature period. D -value was determined as an appropriate index for drought resistance identification. Ganpi 7, Z06-278-9, MERIT, NEVADA, and Xizang 25 were identified as drought resistant barley materials at mature period, which could provide basic materials for the researches on cultivar breeding, drought resistant mechanism, and regulation and alleviation mechanism of drought resistance in barley. The spike length, grain number per plant, grain weight per plant, grain number per spike and yield could be used as the simple and intuitive identification indexes of drought resistance in barley resources at mature period.

高温条件下稀土尾砂干旱对4种植物生理特性的影响

PDF HTML阅读 XML下载 导出引用 引用提醒 高温条件下稀土尾砂干旱对4种植物生理特性的影响 DOI: 10.5846/stxb201804180882 作者: 作者单位: 南昌工程学院 水利与生态工程学院,南昌工程学院 水利与生态工程学院,南昌工程学院 水利与生态工程学院,南昌工程学院水利与生态工程学院,南昌工程学院 水利与生态工程学院,南昌工程学院 水利与生态工程学院,南昌工程学院 水利与生态工程学院 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（51669015）；江西省水利厅科技项目（KT201540）；水利部鄱阳湖水资源水生态环境研究开放基金（ZXKT201510） Effects of drought on physiological characteristics of seedlings of four species grown on rare earth mill tailings at high temperatures Author: Affiliation: College of Water and Ecology Engineering，Nanchang Institute of Technology,,,,,, Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:稀土矿尾砂区地表大面积裸露，土壤结构遭到破坏，保水性能差，植物生长受到严重的干旱胁迫，季节性高温干旱期甚至威胁植物的生存。以稀土矿区周边广泛分布的枫香、木荷、樟树和桉树4种植物为研究对象，对比分析高温干旱条件下4种植物幼苗的光合特征、水分利用效率（WUE）、渗透调节物质和抗氧化酶活性等生理特征及适应性，为稀土尾砂矿区生态修复中植物的筛选提供理论依据。结果显示，高温干旱（空气温度40℃，土壤含水量2%左右）条件下，4种植物的光合速率（Pn）、气孔导度（Gs）、蒸腾速率（Tr）和叶绿素（Chl）含量显著低于高温丰水条件（空气温度40℃，土壤含水量15%左右），光合作用受到抑制，WUE升高；不管高温丰水还是干旱条件下，樟树WUE最高；干旱条件下枫香和桉树的丙二醛（MDA），木荷和桉树的可溶性糖、脯氨酸（Pro）和可溶性蛋白，以及所有植物的过氧化物酶活性（超氧化物歧化酶（SOD）、过氧化物酶（POD）、过氧化氢酶（CAT））均显著高于丰水条件。隶属函数评价得出4种植物幼苗抗高温干旱的等级为樟树 > 桉树 > 木荷 > 枫香；灰色关联分析发现WUE和可溶性糖与抗旱性关联最大，其次为CAT、Pro和MDA，可溶性蛋白与抗旱性关联最小。其中，樟树通过提高WUE、可溶性糖和CAT来应对干旱，桉树通过可溶性糖和MDA响应干旱胁迫，木荷在Pro调节下体现抗旱性，枫香则通过可溶性蛋白来抗旱。因此，在稀土尾砂植被恢复中关于乔木树种的选择可优先考虑樟树。 Abstract:Mining rare earth minerals by heap leaching processes imposes substantial threats to the soil in rare earth ore areas, including the destruction of soil structures and the exposure of the ground surface over large areas, which together leads to poor soil water retention and severe soil erosion. Consequently, the growth and survival of plants in these areas are likely to be threatened by soil water deficit, especially during the drought season when air temperatures are frequently very high. To improve the ecological environments of rare earth mill tailings, effective restoration strategies are urgently needed, of which screening for suitable plants is a critical step for ecological recovery. In this study, four woody plant species (Liquidambar formosana, Schima superba, Eucalyptus grandis, and Cinnamomum camphora) that are widely distributed around rare earth mine tailings were selected and tested for their physiological responses to drought stress at high temperatures, and the photosynthetic traits, water use efficiency (WUE), osmotic regulation substances, and antioxidant enzymes activities of seedlings were measured. All four species grown under the drought treatment (with soil water content at 2% and air temperature at 40℃) had significantly lower photosynthetic rates (Pn), stomatal conductance (Gs), and transpiration rates (Tr) than those in the wet treatment (with soil water content at 15% and air temperature at 40℃), but there was a higher WUE for seedlings under the drought condition compared to seedlings in the wet treatment. C. camphora had the highest WUE regardless of soil water status. Malondialdehyde (MDA) in L. formosana and E. grandis, the soluble sugar, proline (Pro), the soluble protein in S. superba and E. grandis, and the peroxidase activity of all species under the drought condition were significantly higher than those in wet. The comprehensive evaluation on physiological indexes based on the subordinate function value method indicated that the sequence for drought resistance of the four plants at high temperatures was C. camphora, E. grandis, S. superba, and L. formosana. The gray correlation analysis showed that WUE and soluble sugar had the largest correlation with drought resistance, followed by CAT, Pro and MDA. On the other hand, soluble protein was least correlated with drought resistance. Overall, C. camphora coped with drought stress at high temperatures by improving WUE and accumulating soluble sugar and CAT jointly, while E. grandis coped with drought stress by accumulating soluble sugar and MDA. For the other two species, S. superba responded to drought through the proline regulation, while L. formosana regulated their soluble proteins in resistance to drought. Therefore, C. camphora could be a priority for vegetation restoration in rare earth mill tailings. 参考文献 相似文献 引证文献

Physiological responses to drought in three provenances of Discorea nipponica Makino

Dioscorea nipponica Makino is an optimal candidate to develop the diosgenin industry in North China. Given the large fluctuations in soil water availability induced by global climate change, information on drought tolerance of this species is urgently needed. Thus, seedlings of three provenances, selected from Manghe, Pangquangou nd Luyashan Nature Reserves in Shanxi Province, were exposed to 70%-85%, 55%-60%, 40%-45% and 20%-35% of water holding capacity, representing normal-watered, light drought stress, moderate drought stress and severe drought stress, respectively. Thirteen indices concerning plant water status, photosynthesis, antioxidants and osmotic regulation were recorded. Principal Component Analysis was applied to identify indices with a high contribution to drought tolerance, fulfilled by the average of subordinate function values (Xij) of drought tolerance index (Xij).We found that rhizome-propagated seedlings of D. nipponica Makino could survive eighty days of severe drought. The drought tolerance of this species is achieved mainly through physiological responses including decreased photosynthesis, increased activity of antioxidant enzymes, and accumulation of osmotic regulating compounds. The means of drought tolerance index for the provenances Manghe, Pangquangou and Luyashan were 0.29, 0.68 and 0.50, respectively. Pangquangou provenance showed higher drought tolerance than the other two, indicating that it might be a good candidate for cross breeding to combat the increasing drought climate in Shanxi Province.

Genotypic differences and glutathione metabolism response in wheat exposed to copper

In recent years, wheat (Triticum aestivum L.) yields have declined as a result of heavy metal pollution. In this study, hydroponics experiments were conducted to assess the genotypic differences in copper (Cu) tolerance and glutathione metabolism in wheat. Thirty-seven wheat cultivars from different primary cultivation areas in China were selected and exposed to Cu stress for 48 h. Six growth and physiological indexes in the young roots were measured, and a comprehensive evaluation of the resistance of wheat to Cu was achieved using correlation analysis, subordinate function analysis, and the median clustering method. Based on the average subordinate function values, the 37 wheat cultivars could be classified into a high Cu-resistant, medium Cu-resistant, and sensitive group. The root transcriptome of ‘Jimai 22’ (high Cu-resistant) and ‘Luomai 23’ (sensitive) under Cu stress was further sequenced using lllumina sequencing technology. The results showed that a total of 49,611 and 43,195 genes were discovered in Jimai 22 and Luomai 23, respectively, in response to Cu. Gene Ontology term enrichment combined with pathway analysis indicated that 26 overrepresented up-regulated DEGs were associated with glutathione metabolism in Jimai 22, while 17 DEGs associated with glutathione metabolism were identified in Luomai 23. Eight of the 13 unique DEGs in Jimai 22 encoded glutathione S-transferases (GST). In addition, the activity of enzymes, including glutathione reductase (GR), glutathione-S-transferase (GST) and ascorbate peroxidase (APX) were measured in the roots. Furthermore, the contents of ascorbate (ASC), reduced glutathione (GSH), oxidized glutathione (GSSG), and some nutrients, including Cu, potassium, calcium, magnesium, sodium, manganese, and zinc, were also determined. The results clearly indicated that excess Cu affected the concentrations of non-enzymatic antioxidants and nutrients (except for Cu). Besides that, APX activity in wheat was affected by excess Cu and it was higher in Jimai 22. On the contrary, GST and GR activity increased with Cu stress treatment for 48 h.

Cause analysis and safety evaluation of aluminum powder explosion on the basis of catastrophe theory

A safety state catastrophe model of aluminum product plant was established in this study by analyzing the causes of aluminum powder explosions. This model, which was developed from the perspectives of humans and objects, was created to explore the cause of aluminum powder explosions and establish a safety evaluation model. Weight is influenced by subjective factors in the safety evaluation of plants. Thus, a safety evaluation method based on catastrophe theory was proposed to analyze aluminum powder explosion. Fuzzy analysis method was combined with the hierarchical decomposition of the evaluation object. Normalization formula was used to compute the overall value of catastrophe subordinate function to realize the evaluation and dynamic judgment of the safety level of plants. Management system, operator, facilities and equipment, and the environment are the main factors that affect the safety level of aluminum product plants. The total value of safety catastrophe subordinate function of an aluminum product factory is determined by the minimum value of catastrophe subordinate function values at criterion layers. The four factors must be comprehensively considered. The evaluation method involves simple calculation, requires no index weighing, and realizes the dynamic and safe evaluation of aluminum product factories using multiple assessment indices.

Association analysis of drought tolerance in cut chrysanthemum (Chrysanthemum morifolium Ramat.) at seedling stage.

Understanding the genetic architecture is a prerequisite for crop improvement. The current research aimed to characterize the extent of genetic variation of drought tolerance harbored in a global collection of 159 chrysanthemum cultivars over 2years. An average subordinate function value (ASFV), integrating the wilting index, the fresh weight retention rate, and the survival rate after re-watering under two drought-stressed trials, was used to quantify the level of drought tolerance. The performance of ASFV was generally correlated between the 2years; and a high magnitude (0.95) of broad-sense heritability, coupled with the moderate genetic advance, was estimated for the ASFV. By applying MLM model with both population structure and kinship matrix as covariates association mapping identified 16 markers linked to drought tolerance, with the proportion of the phenotypic variation explained by an individual marker ranging from 4.4 to 7.6%. Of the eight markers predictive across the 2years, four (E11M24-9, E3M2-8, E1M5-5, and EST-SSR34-3) were identified as favorable alleles for drought tolerance. Several cultivars that carry at least three of the four favorable alleles were identified as potential donor parents for future improvement of the drought tolerance. The findings provide an insight into the genetic basis of the drought tolerance in chrysanthemum and will, therefore, aid in developing new cultivars with enhanced tolerance against drought stress.

Relation between level of autumn dormancy and salt tolerance in lucerne (Medicago sativa)

Experiments were conducted to study the relationship between autumn (fall) dormancy rating (FDR) and salt tolerance of lucerne (alfalfa, Medicago sativa L.). Seeds of eight cultivars with different FDRs (range 2.0–10.2) were germinated in a growth chamber under five concentrations of NaCl (range 0–1.2%). A subordinate function value method was adopted for comprehensive evaluation of salt tolerance of the lucerne cultivars. Seed germination rate and germination potential, and seedling electrolyte leakage, shoot length, root length, fresh weight, root : shoot length ratio, Na+ and K+ concentrations and K+ : Na+ ratio were used as the indices of evaluation. Under 1.2% salt treatment, salt-tolerance ranking of the cultivars was WL656HQ &gt; WL440HQ &gt; WL712HQ &gt; WL525HQ &gt; WL343HQ &gt; WL319HQ &gt; WL363HQ &gt; WL168HQ, with respective FDRs of 9.3, 6.0, 10.2, 8.2, 3.9, 2.8, 4.9 and 2.0. The results of this study show that non-dormant cultivars were generally more salt tolerant than dormant cultivars.

基于CVM的海涂湿地生态服务价值的模糊评估模型

PDF HTML阅读 XML下载 导出引用 引用提醒 基于CVM的海涂湿地生态服务价值的模糊评估模型 DOI: 10.5846/stxb201705210937 作者: 作者单位: 1.宁波大学 2.宁波大红鹰学院,宁波大学 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金面上项目（71771128）；宁波市人民政府与中国社会科学院合作共建研究中心2017年立项课题（NZKT201729）；浙江省软科学项目（2017C35088） The fuzzy evaluation model of beach wetland ecosystem service value based on the contingent value method Author: Affiliation: 1.Business School of Ningbo University;2.Ningbo DaHongYing University,Ningbo University Fund Project: The National Natural Science Foundation of China;soft science project of Zhejiang province 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:正确评估海涂湿地生态服务价值有助于加强人们保护海涂湿地的意识，为海涂湿地围垦生态补偿标准的制定提供依据。视价格"便宜"、"适中"和"昂贵"为模糊集，基于CVM法区间型数据建立了传统模糊统计模型、赋权模糊统计模型和三相划分模型，并以此评价了杭州湾国家湿地公园单位面积年生态系统服务价值。结果显示：3种方法得到的单价分别为10.28、10.38、9.76元m-2 a-1，三者一致程度较高，与国内沿海湿地价值比较接近。分析了"生态价值"概念客观上的"模糊性"引致模糊数学模型的合理性；采用"橄榄球"式赋权建立赋权模糊统计模型以克服传统模糊统计模型中对区间数据均匀赋权的不合理性，结果在隶属度函数的光滑性和拟合度上好于后者；第三，三相划分模型拟合出3个模糊集的隶属度函数，可以比较相同价格在不同模糊集中隶属度差异。建立的模型对于基于CVM法的生态资源价值评估具有借鉴意义。 Abstract:Properly evaluating the beach wetland ecological services value will contribute to the awareness of beach wetland protection for people, and provide basis for the planning of beach wetland reclamation ecological compensation criterion. The scientific nature of traditional classification calculation method of ecological services value is disputing, and the common CVM data handling techniques have some limits on the recognition of investigation results analysis. This research establishes a fuzzy evaluation model for beach wetland ecological services value based on CVM method. The prices "cheap", "moderate" and "expensive" are three fuzzy subsets for specific domains of discourse. This paper highlights the comparison of different membership grades for different prices on different fuzzy subsets, establishes a traditional fuzzy statistical model, weighted fuzzy statistical model and three-phase model according to non-uniform discrete membership grades, weighted discrete membership grades and successive membership grades based on the interval data of CVM, and evaluates the annual ecological services value per unit area of Hangzhou Bay National Wetland Park. The results showed that:the unit prices obtained through 3 methods are 10.28 Yuan/m2, 10.38 Yuan/m2 and 9.76 Yuan/m2, which have high uniform degree and similar with domestic beach wetland values. The interval of moderate price for wetland ecological services is[5.46,15.33] which is obtained when dividing the model through three phases and the subordinate function values of each "moderate" price in the moderate price interval are higher than the subordinate function values of "cheap" and "expensive". Innovations of this study are as follows. First, the innovation value is the rationality of fuzzy mathematical model analyzed through the conceptual "fuzziness" of "ecological value", and find the representative price from the maximal onset principle of membership grade, which is different with the data central tendency principle of traditional CVM data processing; second, the "rugby" type weighted statistical model established can overcome the irrationality of the uniform weighting to interval data of the traditional fuzzy statistical model, and the results of smoothness and degree of fitting on the membership function are better than the traditional model; third, three-phase model fits the membership functions for three subsets which could compare the membership grades difference of different fuzzy subsets with same prices. The established model is reference significance for the evaluation of ecological resources value based on CVM. 参考文献 相似文献 引证文献

Evaluation of drought resistance in Iris germanica L. based on subordination function and principal component analysis

Drought is one of the major environment stresses that have a wide range of impact on plants. In this study, seven physiological indexes including the content of soluble protein (SP), chlorophyll (Chl) and malondialdehyde (MDA), superoxide dismutase (SOD) and peroxidase (POD) activities, leaf relative water content (RWC), rate of water loss (RWL) from excised leaves were measured in leaves of Iris germanica before and after the drought treatment. It was found that the content of MDA and SP, POD and SOD activity increased, while RWL and RWC decreased in response to drought stress. Based on the subordinate function values of seven physiological indexes, seven single indexes were transformed into three principal components namely damage degree, active oxygen removal ability and moisture condition and the composite score (F value) of each iris variety was calculated by principal component analysis (PCA). Based on the F values, 10 iris cultivars could be divided into three groups by cluster analysis (CA): drought-resistance (2 varieties), medium drought-resistance (5 varieties), and low drought-resistance (3 varieties). Meanwhile, optimum regression equation was constructed. Therefore, this work provides a comprehensive and reliable method for evaluating drought resistance in the varieties of Iris germanica.

Analysis and comprehensive evaluation on cold resistance of six varieties of Michelia

Taking six varieties of Michelia as test materials, their responses under cold situation in the field were investigated and the semilethal low temperatures were calculated by fitting Logistic equation. The nine structure indexes of leaf tissue were observed by paraffin section, and a comprehensive evaluation on cold resistance of different varieties was given according to subordinate function value analysis. The results showed that the relative electrical conductivity of six varieties of Michelia was significantly positively correlated with the semilethal low temperature (LT50) of 3 h 0-25 ℃ treatment. From high to low, the order of LT50, which ranged between -20.48 ℃and -8.67 ℃, was M. maudiae ＞ M. maudiae var. rubicunda ＞ M. wilsonii ＞ M. 'liubanhanxiao' ♀× M. shiluensis ♂ ＞ M. platypetala ＞ M. 'liubanhanxiao'. The epidermal anticlinal walls of six varieties of Michelia leaves had 1-2 layers and showed slightly sinuated shape. The leaf had 1-3 layers of palisade tissue cells and the differences among the indexes of nine anatomical structures were extremely significant. The thickness of palisade tissue, ratio between palisade tissue and spongy tissue, and thickness of the vein were the key factors affecting cold resistance. The order of cold resistance of six varieties of Michelia, from the strong to the weak, was M. 'liubanhanxiao' ＞ M. platypetala ＞ M. 'liubanhanxiao' ♀× M. shiluensis ♂＞M. wilsonii ＞ M. maudiae var. rubicunda ＞ M. maudiae, which was basically consistent with the result of field investigation.