The impacts of climate change on crop yields are receiving renewed interest,with focus on cereals and staple crops at the regional and national scales.Yet,the impacts of climate change on the yields of leguminous crop...The impacts of climate change on crop yields are receiving renewed interest,with focus on cereals and staple crops at the regional and national scales.Yet,the impacts of climate change on the yields of leguminous crops in the local context has not been explored.Thus,an in-depth understanding of climate change in the local context may support the design of locally relevant adaptation responses to current and future climate risks.This study examined the impacts of climate variables(annual rainfall,annual average temperature,rainfall indices(rainfall onset,rainfall cessation,and the length of rainy days),and the number of dry days)on the yields of leguminous crops(groundnuts,cowpeas,and soybeans)in the Guinea Savanna agroecological zone of Ghana during the period of 1989-2020.The data were analysed using Mann-Kendall’s trend,Sen’s slope test,correlation analysis,and Multiple Regression Analysis(MRA).The findings revealed that annual rainfall,annual average temperature,rainfall onset,rainfall cessation,and the length of rainy days,and the number of dry days all showed varied impacts on the yields of groundnuts,cowpeas,and soybeans.The trend analysis detected a marginal decrease in the amount of rainfall,rainfall onset,and the number of dry days from 1989 to 2020(P>0.050).Annual average temperature and the length of rainy days substantially varied(P<0.050)from 1989 to 2020,showing an increasing trend.The findings also showed a marked upward trend for the yields of groundnuts,cowpeas,and soybeans during 2005-2020.The climate variables analysed above increased the yields of groundnuts,cowpeas,and soybeans by 49.0%,55.0%,and 69.0%,respectively.The yields of groundnuts,cowpeas,and soybeans fluctuated with the variability of 30.0%,28.0%,and 27.0%from 2005 to 2020,respectively.The three leguminous crops under study demonstrated unpredictable yields due to the variations of annual rainfall,annual average temperature,rainfall onset,rainfall cessation,the length of rainy days,and the number of dry days,which stressed the need for agricultural diversification,changing planting dates,using improved seed variety,and irrigation to respond to climate change.The results of this study implied that climate change considerably impacts crop production in the Guinea Savanna agroecological zone of Ghana,emphasizing the urgency of locally based and farmer-induced adaptation measures for food security and resilient agricultural systems.展开更多
[Objective] To study the differences in the tolerance of leguminous crops and cruciferous crops to microcystin (MC). [Methed] The cruciferous typical crops oilseed rapes, pakchois, cabbages and leguminous typical cr...[Objective] To study the differences in the tolerance of leguminous crops and cruciferous crops to microcystin (MC). [Methed] The cruciferous typical crops oilseed rapes, pakchois, cabbages and leguminous typical crops soybeans, peas and broad beans were selected as the materials to test the effects of MC of differ- ent concentrations on the germination, growth and development of leguminous crops and cruciferous crops. The measurement indicators included germination rate, plant height, chlorophyll, etc. [Result] The MC had great effects on the oilseed rape and pakchois of cruciferous crops, and smaller effects on cabbage, while the leguminous crops were generally not affected. [Conclusion] Leguminous crops are more tolerant to MC than cruciferous crops and more preferential in MC polluted regions.展开更多
Calcaric regosols are a valuable land resource, distributed widely across western China. Soil quality has deteriorated considerably in recent years owing to the blind pursuit of economic benefits. A 2-year field exper...Calcaric regosols are a valuable land resource, distributed widely across western China. Soil quality has deteriorated considerably in recent years owing to the blind pursuit of economic benefits. A 2-year field experiment was carried out to evaluate the effects of using spent mushroom compost, leguminous plant (Vicia sepium L.) compost, and a combination of the two (at a 1:1 and 2:1 ratio), on rice yield and soil quality in a suburb of China. Vicia sepium L. composted with spent mushroom compost at a 1:1 ratio produced the highest grain and stover yield, grain and stover phosphorus concentration, and phosphorus uptake of rice; they were 56.5%, 93.2%, 89.3%, 198.6% and 22.2% greater than control soil, respectively. The 2:1 ratio (Vicia sepium L.: spent mushroom compost) produced the highest grain N concentration, stover N concentration, and N uptake; they were 31.6%, 31.4%, and 40.7% higher than control, respectively. Soil physical, chemical, and environmental properties were improved with the application of Vicia sepium L. composted with spent mushroom compost at a 2:1 ratio. In particular, soil water-stable aggregates, organic carbon, particulate organic carbon, total nitrogen, available potassium, and cation exchange capacity increased, whereas bulk density, pH, and phytoavailable heavy metals decreased. This organic treatment is beneficial to improve soil quality indicators, and contribute to soil restoration.展开更多
An in vitro rumen gas production technique was employed to determine the methane production and fermentation characteristics of Leymus chinensis and Medicago ruthenica at differing harvest dates(May 15,May 30,June 30...An in vitro rumen gas production technique was employed to determine the methane production and fermentation characteristics of Leymus chinensis and Medicago ruthenica at differing harvest dates(May 15,May 30,June 30,July 30,August 30 and September 30),which are sequential phases within a single continuous growth of two 10-year-old pastures.To quantify the rate of degradation and compare in vitro rumen fermentation characteristic,a logistic-exponential model,where initial gas volume was zero(LE_0),was used to fit gas production and methane output results.Dried,milled forage samples were incubated in vitro for 72 h at 39℃ and gas production was recorded intermittently throughout the incubation and gas samples were collected to measure methane production.Results showed that there were significant interactions between species and harvest for all chemical composition variables(P〈0.001) and condensed tannin content(P〈0.001).L.chinensis produced more total gas and methane than M.ruthenica(P〈0.001).Both total gas and methane production decreased lineally(P〈0.001) with advancing harvest date.The degradation rates of L.chinensis and M.ruthenica harvested on September 30 were lower than those on the other harvest dates(P〈0.01).M.ruthenica fermented fluid had higher concentration of ammonia N(P〈0.05) and molar proportions of isobutyrate(P〈0.01),valerate(P〈0.001) and isovalerate(P〈0.01) in total volatile fatty acids than L chinensis.Furthermore,concentration of isovalerate decreased cubically with advancing harvest date(P〈0.05).In conclusion,M.ruthenica produced less methane than L.chinensis and the total gas and methane production decreased with advancing harvest date for both species,which may be due to the changes in contents of chemical compositions and condensed tannin in forages.展开更多
Soil microbial biomass is an active fraction of soil organic matter. It shows quicker response than soil organic matter to any change in the soil environment. Being an index of soil fertility, it plays a key role in t...Soil microbial biomass is an active fraction of soil organic matter. It shows quicker response than soil organic matter to any change in the soil environment. Being an index of soil fertility, it plays a key role in the decomposition of litters and fast release of available nutrients. Leaf litters of leguminous and non-leguminous species in alone and mixed form were applied as treatments in the soil to observe the changes in the magnitude of soil microbial biomass. Soil microbial biomass C and N were determined by chloroform fumigation extraction method. Increment in the concentration of microbial biomass C and N was higher in the treatments with leguminous leaf litter (497 - 571 μgCg?1, 48 - 55 μgNg?1) than the non-leguminous one (256 - 414 μgCg?1;22 - 36 μgNg?1). However, when non-leguminous litters were mixed with leguminous litters then the values increased distinctly (350 - 465 μgCg?1, 28 - 48 μgNg?1). On the basis of increment in soil microbial biomass, leaf litters of the species considered potential to improve soil nutrients are—Cassia siamea and Dalbergia sissoo from leguminous trees, Anthocephalus + Cassia and Shorea + Dalbergia from mixed form of non-leguminous and leguminous one and Eichhornia crassipes, an alien aquatic macrophyte. The leaf litters of these species can be used as source of organic matter to improve the crop yield.展开更多
Agricultural activities that encourage slashing, burning and ploughing greatly affect the soil structure and soil organic matter on which soil water retention depends. In this study, we hypothesized that inclusion of ...Agricultural activities that encourage slashing, burning and ploughing greatly affect the soil structure and soil organic matter on which soil water retention depends. In this study, we hypothesized that inclusion of rotational leguminous tree species improves soil water retention in a semi-arid conservation agriculture system. In a study done in Kibwezi, semi-arid eastern Kenya, results showed that the amount of water retained in the different soil strata from plots with different tree species and tillage practices was highly significant (P = 0.032). Plots with planting basins and Gliricidia sepium and Faidherbia albida tree species retained more water in both the upper and lower strata. Plots with G. sepium tree species under planting basins and zero tillage under F. albida had significantly higher soil organic carbon levels than plots that were managed under ridges and ploughing (P = 0.002). On the other hand, bulk density in plots with planting basins and zero tillage and ridges ranged between 1.35 g/cm3 and 1.53 g/cm3. Conventional tillage plots had bulk density values of 1.65 g/cm3 and 1.72 g/cm3 in the upper and lower strata respectively. The time-dependent nature of rotational leguminous tree species on soil organic matter and soil water retention in the semi-arid conservation agriculture system highlights the importance of considering these species for improving organic carbon and water retention for improved crop production.展开更多
The profile of polypeptides separated by SDS-PAGE from seed of major crop species such as pea (Pisum sativum) is complex, resulting from cleavage (processing) of precursors expressed from multiple copies of genes enco...The profile of polypeptides separated by SDS-PAGE from seed of major crop species such as pea (Pisum sativum) is complex, resulting from cleavage (processing) of precursors expressed from multiple copies of genes encoding vicilin and legumin, the major storage globulins. Translation in vitro of mRNAs hybrid-selected from mid-maturation pea seed RNAs by denned vicilin and legumin cDNA clones provided precursor molecules that were cleaved in vitro by a cell-free protease extract obtained from similar stage seed; the derived polypep tides were of comparable sizes to those observed in vivo. The feasibility of transcribing mENA in vitro from a cDNA clone and cleavage in vitro of the derived translation products was established for a legumin clone, providing a method for determining polypeptide products of an expressed sequence. This approach will also be useful for characterising cleavage site requirements since modifications an readily be introduced at the DNA level.展开更多
Proteolysis of seed storage proteins (SSP) during germination provides a steady supply of amino acids to the embryo development into seedling. This process is coordinated by different peptidases that act sequentially ...Proteolysis of seed storage proteins (SSP) during germination provides a steady supply of amino acids to the embryo development into seedling. This process is coordinated by different peptidases that act sequentially and overlaid mode. These enzymes are an ancient group evolved separately in a wide structural and functional diversity and have many applications in medicine, pharmacy and industry. However, the knowledge about seed peptidases during germination was obtained from studies almost restricted to the cultivated species. This restriction implies caution about generalizations made from these studies, as well limits the biological knowledge about plant kingdom and technological use from plant peptidases. In this work, a scan of the proteolytic activity was held in germinating seeds of a leguminous subtropical woody tree. Eleven proteolytic activities were detected in protein extracts from embryonic axis and cotyledons. The presence and intensity of these activities varied over time and between these tissues. There was indication that aspartyl-endopeptidases (phytepsins) and cysteine-carboxypeptidases (plant cathepsins) were involved in A. colubrina SSP hydrolysis. These peptidases differ to that commonly involved in germination of the cultivated leguminous. In addition, one of detected phytepsins showed stability on pH scale, which is important for industrial uses. There was also detected a metallo-carboxypeptidase activity, which has been not described in plants. These peptidases must be isolated to confirm or not these indications. However, these data indicate the biological and technological importance of extending the studies about plant peptidases on a diverse genetic basis.展开更多
This study was carried out to assess the relationship of the status of nodulation(i.e., the number of nodules, their shape and size) in root and biomass production of plant growth parameters(i.e., number of leaves, ro...This study was carried out to assess the relationship of the status of nodulation(i.e., the number of nodules, their shape and size) in root and biomass production of plant growth parameters(i.e., number of leaves, root and shoot lengths, root biomass and shoot biomass) in Albizia saman and Leucaena leucocephala. The assessment started 60 days after seeding. The study revealed that nodulation response and biomass production in both species showed significant differences over time(p < 0.05) in all variables except in the root-shoot ratio(oven-dry) of L. leucocephala. The study also showed significant differences(p < 0.05) in nodule formation and biomass production at the end of the study period between the two species except in the number of nodules and leaves and the green root-shoot ratio. There were strong positive correlations between nodule formation and biomass production, i.e., the number of nodules and the age of plants, the number of nodules and leaves, as well as the number of nodules and biomass(root biomass and shoot biomass) in both species. The results obtained using principal component analysis(PCA) and correlation coefficients of the different characteristics of nodulation and biomass production were similar in both species. The PCA showed that shoot biomass(shoot green weight and shoot oven-dry weight) is positively correlated with PC1(with an eigenvalue of 7.50) and root length is positively correlated with PC2(with an eigenvalue of 0.19) in the case of A. saman. In the case of L. leucocephala, the PCA revealed that root biomass(root green weight and root oven-dry weight), shoot biomass and shoot length are also positively correlated with PC1, while nodule formation and the number of leaves are positively correlated with PC2(with an eigenvalue PC1 of 6.92 and PC2 of 0.49).展开更多
The content of chemical compounds of two leguminous plants (Alysicarpus ovalifolius and Indigofera pilosa) was given through chromatographic methods (HPLC) and spectrocolorimetry. The principal isolated compounds are:...The content of chemical compounds of two leguminous plants (Alysicarpus ovalifolius and Indigofera pilosa) was given through chromatographic methods (HPLC) and spectrocolorimetry. The principal isolated compounds are: β-Carotene in the sheets, the vitamin B in the roots and the vitamin C in the pods. Trace elements are not also insulated in the two plant species. The results show a content iodine (0.27 mg/100g of sample) particularly high in the stems of Indigofera pilosa, what could explain the use of the plant to fight against the thyroid dysfunctions. The ratio iron in mg/100g of sample 114.14 is rather important and would make Indigofera pilosa a palliative against anaemia. The two plants would be indicated in cases of treatment of hypocalcaemia.展开更多
The presence of trees in the pastures can bring several benefits to both the animals and to the soil under their influence.Thus,the objective of this study was to evaluate the levels of organic carbon and nitrogen und...The presence of trees in the pastures can bring several benefits to both the animals and to the soil under their influence.Thus,the objective of this study was to evaluate the levels of organic carbon and nitrogen under the baru canopy in the soil profile.Four adult baru trees were used.The samplings were made at the four cardinal points at four different distance points from the projection radius of the crown,being:P1=one-third of the crown projection radius length;P2=two-thirds of the crown projection radius length;P3=extremity of the crown projection radius;P4=one and a half times the maximum crown projection radius length.Soil samples were collected at each point at depths of 0-0.10,0.10-0.20 and 0.20-0.40 m.Organic carbon and nitrogen contents were evaluated and the C/N ratio was calculated.The baru trees influenced the soil organic and carbon contents in the areas under their canopy.The organic carbon and nitrogen contents were higher in relation to the tree trunk(P1)and also in the most superficial layer of the soil(0-0.10 m).The C/N ratio was higher outside the tree canopy and in the deeper layer.展开更多
Acacia seyal is a leguminous plant that plays an important role in the ecosystem of Sahelian zone by producing gum, wood and fodder. The growth of A. seyal is subject to many constraints as salinity which can affect t...Acacia seyal is a leguminous plant that plays an important role in the ecosystem of Sahelian zone by producing gum, wood and fodder. The growth of A. seyal is subject to many constraints as salinity which can affect the development of this tree. Therefore, soil microorganisms can help A. seyal to better tolerate the effects of negative environmental stresses. The contribution of arbuscular mycorrhizal fungi (AMF) to the salt tolerance of A. seyal, was evaluated by testing the effects of eight different arbuscular mycorrhizal fungi (AMF) isolates in the performance of A. seyal seedlings subjected to different levels of salinity (0, 340 and 680 mM). The results based on growth parameters of shoot and root parts, shoot mineral N, P, K and Na content as well as survival rates and mycorrhization showed that AMF improved mineral nutrition of A. seyal seedlings during salt stress. The combination between AMF and salinity provided evidence that the efficiency of AMF isolates were variable in improving mineral nutrition and mortality rate for A. seyal seedlings related to the level of salt stress. However, the effects of inoculation were variable depending to the AMF isolate associated with seedlings and the level of salinity, suggesting that interactions between plants and AMF can be modulated by both AMF diversity and the type and level of abiotic factors. Rhizophagus intraradices was more efficient at 680 mM NaCl in plant growth and mineral uptake while Glomus deserticola did not promote a better plant development than most of the other species inoculated to seedlings.展开更多
To better understand the effects of direct sowing under mulch-based cropping system (DMC) in Burkina Faso’s cotton production systems, randomized blocks of Fisher experimental design were implemented at Farako-B<s...To better understand the effects of direct sowing under mulch-based cropping system (DMC) in Burkina Faso’s cotton production systems, randomized blocks of Fisher experimental design were implemented at Farako-B<span style="white-space:nowrap;">a</span> research station from 2010 to 2019. The study was conducted on lixisoil to evaluate DMC effects on biomass production, crops yields and soil chemical properties in a maize and cotton rotation system associated with cover crop. Conventional tillage and direct seeding without cover crop were compared to DMC under <em>B</em>. <em>ruziziensis</em> (GERM. & EVRARD), DMC under <em>B</em>. <em>ruziziensis</em> + <em>M</em><em>.</em> <em>cochinchinensis</em> mulch and DMC under <em>C. juncea</em> (L.) mulch used in association with maize. Biomass production, crop yields and soil chemistry were evaluated. Results showed that over 10 years, no-till with or without a cover crop provided cotton seed and maize yields that were statistically equivalent to the tillage commonly practiced by farmers. Cover crop has allowed increasing the biomass production compared to Conventional Tillage and Direct Seeding. Maize yield has not varied significantly with the cover crop. After 10 years of maize and cotton rotation, the improvement raised from +27% to +38% for organic matter and from +15% to +29% for nitrogen with DMC including legumes such as <em>M. cochinchinensis</em> and <em>C. juncea</em> compared to Conventional Tillage on 0 - 5 cm depth. No significant differences were found on soil pH like P<sub>2</sub>O<sub>5</sub> and K<sub>2</sub>O content. Although DMC with <em>C. juncea</em> used as cover crop did not provide the best biomass production, it contributes to increase nitrogen and organic matter and presents better mineral balances in 10 years of rotation. The 5 - 10 cm and 10 - 20 cm were little influenced by DMC systems.展开更多
The investigation was conducted to determine physiological criteria of early selection for salt tolerant leguminous plants. Plants were subjected to 5 levels of salt stress at the roots (0, 50, 100,150 and 200 mM NaC...The investigation was conducted to determine physiological criteria of early selection for salt tolerant leguminous plants. Plants were subjected to 5 levels of salt stress at the roots (0, 50, 100,150 and 200 mM NaCI). Results showed that sodium chloride had an underrating effect on growth of stems and seed germination of the species studied. The germination rates of seeds of Glycine max and Phaseolus vulgaris (sensitive glyeophytes) were affected from 3 g/L of NaCl, with critical thresholds at 9 and 12 g/L respectively. In contrast, critical thresholds with Mucunapoggei (facultative halophyte), Vigna unguiculata (moderately tolerant glycophyte) and P. adenanthus (natural halophyte) was found to be above 21 g/L. The reduction of stems growth rate were not significant in P. adenanthus whereas in M. poggei and V. unguiculata this inhibition was observed just when nutritive solutions were enriched with 200 mM. The lipid contents were reduced in all the species under salt stress, whereas proteins and proline contents in the leaves were substantially increased in tolerant species (M. poggei, P. adenanthus and V. unguiculata). In contrast, proteins and leaf proline contents were negatively affected by salt concentration to G. max and P. vulgaris. Seed germination, proteins and proline could be used as physiological criteria of early selection for salt tolerant leguminous plants.展开更多
Plant roots and their associated mycorrhizal fungi critically mediate the decomposition of soil organic carbon(C),but the general patterns of their impacts over a broad geographical range and the primary mediating fac...Plant roots and their associated mycorrhizal fungi critically mediate the decomposition of soil organic carbon(C),but the general patterns of their impacts over a broad geographical range and the primary mediating factors remain unclear.Based on a synthesis of 596 paired observations from both field and greenhouse experiments,we found that living roots and/or mycorrhizal fungi increased organic C decomposition by 30.9%,but low soil nitrogen(N)availability(i.e.,high soil C:N ratio)critically mitigated this promotion effect.In addition,the positive effects of living roots and/or mycorrhizal fungi on organic C decomposition were higher under herbaceous and leguminous plants than under woody and non-leguminous plants,respectively.Surprisingly,there was no significant difference between arbuscular mycorrhizal fungi and ectomycorrhizal fungi in their effects on organic C decomposition.Furthermore,roots and/or mycorrhizal fungi significantly enhanced the decomposition of leaf litter but not root litter.These findings advance our understanding of how roots and their symbiotic fungi modulate soil C dynamics in the rhizosphere or mycorrhizosphere and may help improve predictions of soil global C balance under a changing climate.展开更多
High nitrate leaching has been observed from the O horizons of some tropical forests;however,the drivers of high nitrate production(active nitrification)in these O horizons have not yet been identified.This study inve...High nitrate leaching has been observed from the O horizons of some tropical forests;however,the drivers of high nitrate production(active nitrification)in these O horizons have not yet been identified.This study investigated the drivers of active nitrification in the O horizon of tropical forest soils by focusing on two of the most widely recognized controlling factors of nitrification,total N,and pH.We collected mineral and O horizons from eight tropical forests in Cameroon,Indonesia,and Malaysia and measured gross nitrification rates.Some O horizons showed significantly higher gross nitrification rates than mineral horizons,indicating that these O horizons have a high potential for nitrification.Gross nitrification rates in the O horizons were positively correlated with both total N and pH,and the chemical properties(e.g.,total content of N,P,and base cations)were intercorrelated.These correlations suggested that the underlying driver of nitrification in the O horizon was nutrient richness in the litter.Results also indicated a threshold of gross nitrification rates around pH values of 5.5–6.0.We elucidate that active nitrification and subsequent high nitrate leaching from the O horizon could be driven by nutrient-rich litter,possibly derived from soil fertility and tree species.展开更多
文摘The impacts of climate change on crop yields are receiving renewed interest,with focus on cereals and staple crops at the regional and national scales.Yet,the impacts of climate change on the yields of leguminous crops in the local context has not been explored.Thus,an in-depth understanding of climate change in the local context may support the design of locally relevant adaptation responses to current and future climate risks.This study examined the impacts of climate variables(annual rainfall,annual average temperature,rainfall indices(rainfall onset,rainfall cessation,and the length of rainy days),and the number of dry days)on the yields of leguminous crops(groundnuts,cowpeas,and soybeans)in the Guinea Savanna agroecological zone of Ghana during the period of 1989-2020.The data were analysed using Mann-Kendall’s trend,Sen’s slope test,correlation analysis,and Multiple Regression Analysis(MRA).The findings revealed that annual rainfall,annual average temperature,rainfall onset,rainfall cessation,and the length of rainy days,and the number of dry days all showed varied impacts on the yields of groundnuts,cowpeas,and soybeans.The trend analysis detected a marginal decrease in the amount of rainfall,rainfall onset,and the number of dry days from 1989 to 2020(P>0.050).Annual average temperature and the length of rainy days substantially varied(P<0.050)from 1989 to 2020,showing an increasing trend.The findings also showed a marked upward trend for the yields of groundnuts,cowpeas,and soybeans during 2005-2020.The climate variables analysed above increased the yields of groundnuts,cowpeas,and soybeans by 49.0%,55.0%,and 69.0%,respectively.The yields of groundnuts,cowpeas,and soybeans fluctuated with the variability of 30.0%,28.0%,and 27.0%from 2005 to 2020,respectively.The three leguminous crops under study demonstrated unpredictable yields due to the variations of annual rainfall,annual average temperature,rainfall onset,rainfall cessation,the length of rainy days,and the number of dry days,which stressed the need for agricultural diversification,changing planting dates,using improved seed variety,and irrigation to respond to climate change.The results of this study implied that climate change considerably impacts crop production in the Guinea Savanna agroecological zone of Ghana,emphasizing the urgency of locally based and farmer-induced adaptation measures for food security and resilient agricultural systems.
基金Supported by the Key Technologies R&D Program of Henan Province(092102110105)the Docforal Foundation of Henan Institute of Engineering(D09010)+1 种基金the Critical Patented Projects in the Control and Management of National Polluted Water Bodies(2009ZX07104-005-03,2009ZX07102-003-004,2008ZX07101-007)the Open Lab Project of Hydrobiology Institutes of Chinese Academy of Sciences(2009FBZ09)~~
文摘[Objective] To study the differences in the tolerance of leguminous crops and cruciferous crops to microcystin (MC). [Methed] The cruciferous typical crops oilseed rapes, pakchois, cabbages and leguminous typical crops soybeans, peas and broad beans were selected as the materials to test the effects of MC of differ- ent concentrations on the germination, growth and development of leguminous crops and cruciferous crops. The measurement indicators included germination rate, plant height, chlorophyll, etc. [Result] The MC had great effects on the oilseed rape and pakchois of cruciferous crops, and smaller effects on cabbage, while the leguminous crops were generally not affected. [Conclusion] Leguminous crops are more tolerant to MC than cruciferous crops and more preferential in MC polluted regions.
基金funded by the National Science and Technology Support Project (Grant No.2008BAD7B09-2)
文摘Calcaric regosols are a valuable land resource, distributed widely across western China. Soil quality has deteriorated considerably in recent years owing to the blind pursuit of economic benefits. A 2-year field experiment was carried out to evaluate the effects of using spent mushroom compost, leguminous plant (Vicia sepium L.) compost, and a combination of the two (at a 1:1 and 2:1 ratio), on rice yield and soil quality in a suburb of China. Vicia sepium L. composted with spent mushroom compost at a 1:1 ratio produced the highest grain and stover yield, grain and stover phosphorus concentration, and phosphorus uptake of rice; they were 56.5%, 93.2%, 89.3%, 198.6% and 22.2% greater than control soil, respectively. The 2:1 ratio (Vicia sepium L.: spent mushroom compost) produced the highest grain N concentration, stover N concentration, and N uptake; they were 31.6%, 31.4%, and 40.7% higher than control, respectively. Soil physical, chemical, and environmental properties were improved with the application of Vicia sepium L. composted with spent mushroom compost at a 2:1 ratio. In particular, soil water-stable aggregates, organic carbon, particulate organic carbon, total nitrogen, available potassium, and cation exchange capacity increased, whereas bulk density, pH, and phytoavailable heavy metals decreased. This organic treatment is beneficial to improve soil quality indicators, and contribute to soil restoration.
基金support of the NationalNatural Science Foundation of China(31201820)the Excellent Young Scientists Foundation of the Northeast Institute of Geography and Agroecology,Chinese Academy of Sciences,Changchun,China(DLSYQ12008)
文摘An in vitro rumen gas production technique was employed to determine the methane production and fermentation characteristics of Leymus chinensis and Medicago ruthenica at differing harvest dates(May 15,May 30,June 30,July 30,August 30 and September 30),which are sequential phases within a single continuous growth of two 10-year-old pastures.To quantify the rate of degradation and compare in vitro rumen fermentation characteristic,a logistic-exponential model,where initial gas volume was zero(LE_0),was used to fit gas production and methane output results.Dried,milled forage samples were incubated in vitro for 72 h at 39℃ and gas production was recorded intermittently throughout the incubation and gas samples were collected to measure methane production.Results showed that there were significant interactions between species and harvest for all chemical composition variables(P〈0.001) and condensed tannin content(P〈0.001).L.chinensis produced more total gas and methane than M.ruthenica(P〈0.001).Both total gas and methane production decreased lineally(P〈0.001) with advancing harvest date.The degradation rates of L.chinensis and M.ruthenica harvested on September 30 were lower than those on the other harvest dates(P〈0.01).M.ruthenica fermented fluid had higher concentration of ammonia N(P〈0.05) and molar proportions of isobutyrate(P〈0.01),valerate(P〈0.001) and isovalerate(P〈0.01) in total volatile fatty acids than L chinensis.Furthermore,concentration of isovalerate decreased cubically with advancing harvest date(P〈0.05).In conclusion,M.ruthenica produced less methane than L.chinensis and the total gas and methane production decreased with advancing harvest date for both species,which may be due to the changes in contents of chemical compositions and condensed tannin in forages.
文摘Soil microbial biomass is an active fraction of soil organic matter. It shows quicker response than soil organic matter to any change in the soil environment. Being an index of soil fertility, it plays a key role in the decomposition of litters and fast release of available nutrients. Leaf litters of leguminous and non-leguminous species in alone and mixed form were applied as treatments in the soil to observe the changes in the magnitude of soil microbial biomass. Soil microbial biomass C and N were determined by chloroform fumigation extraction method. Increment in the concentration of microbial biomass C and N was higher in the treatments with leguminous leaf litter (497 - 571 μgCg?1, 48 - 55 μgNg?1) than the non-leguminous one (256 - 414 μgCg?1;22 - 36 μgNg?1). However, when non-leguminous litters were mixed with leguminous litters then the values increased distinctly (350 - 465 μgCg?1, 28 - 48 μgNg?1). On the basis of increment in soil microbial biomass, leaf litters of the species considered potential to improve soil nutrients are—Cassia siamea and Dalbergia sissoo from leguminous trees, Anthocephalus + Cassia and Shorea + Dalbergia from mixed form of non-leguminous and leguminous one and Eichhornia crassipes, an alien aquatic macrophyte. The leaf litters of these species can be used as source of organic matter to improve the crop yield.
文摘Agricultural activities that encourage slashing, burning and ploughing greatly affect the soil structure and soil organic matter on which soil water retention depends. In this study, we hypothesized that inclusion of rotational leguminous tree species improves soil water retention in a semi-arid conservation agriculture system. In a study done in Kibwezi, semi-arid eastern Kenya, results showed that the amount of water retained in the different soil strata from plots with different tree species and tillage practices was highly significant (P = 0.032). Plots with planting basins and Gliricidia sepium and Faidherbia albida tree species retained more water in both the upper and lower strata. Plots with G. sepium tree species under planting basins and zero tillage under F. albida had significantly higher soil organic carbon levels than plots that were managed under ridges and ploughing (P = 0.002). On the other hand, bulk density in plots with planting basins and zero tillage and ridges ranged between 1.35 g/cm3 and 1.53 g/cm3. Conventional tillage plots had bulk density values of 1.65 g/cm3 and 1.72 g/cm3 in the upper and lower strata respectively. The time-dependent nature of rotational leguminous tree species on soil organic matter and soil water retention in the semi-arid conservation agriculture system highlights the importance of considering these species for improving organic carbon and water retention for improved crop production.
文摘The profile of polypeptides separated by SDS-PAGE from seed of major crop species such as pea (Pisum sativum) is complex, resulting from cleavage (processing) of precursors expressed from multiple copies of genes encoding vicilin and legumin, the major storage globulins. Translation in vitro of mRNAs hybrid-selected from mid-maturation pea seed RNAs by denned vicilin and legumin cDNA clones provided precursor molecules that were cleaved in vitro by a cell-free protease extract obtained from similar stage seed; the derived polypep tides were of comparable sizes to those observed in vivo. The feasibility of transcribing mENA in vitro from a cDNA clone and cleavage in vitro of the derived translation products was established for a legumin clone, providing a method for determining polypeptide products of an expressed sequence. This approach will also be useful for characterising cleavage site requirements since modifications an readily be introduced at the DNA level.
文摘Proteolysis of seed storage proteins (SSP) during germination provides a steady supply of amino acids to the embryo development into seedling. This process is coordinated by different peptidases that act sequentially and overlaid mode. These enzymes are an ancient group evolved separately in a wide structural and functional diversity and have many applications in medicine, pharmacy and industry. However, the knowledge about seed peptidases during germination was obtained from studies almost restricted to the cultivated species. This restriction implies caution about generalizations made from these studies, as well limits the biological knowledge about plant kingdom and technological use from plant peptidases. In this work, a scan of the proteolytic activity was held in germinating seeds of a leguminous subtropical woody tree. Eleven proteolytic activities were detected in protein extracts from embryonic axis and cotyledons. The presence and intensity of these activities varied over time and between these tissues. There was indication that aspartyl-endopeptidases (phytepsins) and cysteine-carboxypeptidases (plant cathepsins) were involved in A. colubrina SSP hydrolysis. These peptidases differ to that commonly involved in germination of the cultivated leguminous. In addition, one of detected phytepsins showed stability on pH scale, which is important for industrial uses. There was also detected a metallo-carboxypeptidase activity, which has been not described in plants. These peptidases must be isolated to confirm or not these indications. However, these data indicate the biological and technological importance of extending the studies about plant peptidases on a diverse genetic basis.
文摘This study was carried out to assess the relationship of the status of nodulation(i.e., the number of nodules, their shape and size) in root and biomass production of plant growth parameters(i.e., number of leaves, root and shoot lengths, root biomass and shoot biomass) in Albizia saman and Leucaena leucocephala. The assessment started 60 days after seeding. The study revealed that nodulation response and biomass production in both species showed significant differences over time(p < 0.05) in all variables except in the root-shoot ratio(oven-dry) of L. leucocephala. The study also showed significant differences(p < 0.05) in nodule formation and biomass production at the end of the study period between the two species except in the number of nodules and leaves and the green root-shoot ratio. There were strong positive correlations between nodule formation and biomass production, i.e., the number of nodules and the age of plants, the number of nodules and leaves, as well as the number of nodules and biomass(root biomass and shoot biomass) in both species. The results obtained using principal component analysis(PCA) and correlation coefficients of the different characteristics of nodulation and biomass production were similar in both species. The PCA showed that shoot biomass(shoot green weight and shoot oven-dry weight) is positively correlated with PC1(with an eigenvalue of 7.50) and root length is positively correlated with PC2(with an eigenvalue of 0.19) in the case of A. saman. In the case of L. leucocephala, the PCA revealed that root biomass(root green weight and root oven-dry weight), shoot biomass and shoot length are also positively correlated with PC1, while nodule formation and the number of leaves are positively correlated with PC2(with an eigenvalue PC1 of 6.92 and PC2 of 0.49).
文摘The content of chemical compounds of two leguminous plants (Alysicarpus ovalifolius and Indigofera pilosa) was given through chromatographic methods (HPLC) and spectrocolorimetry. The principal isolated compounds are: β-Carotene in the sheets, the vitamin B in the roots and the vitamin C in the pods. Trace elements are not also insulated in the two plant species. The results show a content iodine (0.27 mg/100g of sample) particularly high in the stems of Indigofera pilosa, what could explain the use of the plant to fight against the thyroid dysfunctions. The ratio iron in mg/100g of sample 114.14 is rather important and would make Indigofera pilosa a palliative against anaemia. The two plants would be indicated in cases of treatment of hypocalcaemia.
文摘The presence of trees in the pastures can bring several benefits to both the animals and to the soil under their influence.Thus,the objective of this study was to evaluate the levels of organic carbon and nitrogen under the baru canopy in the soil profile.Four adult baru trees were used.The samplings were made at the four cardinal points at four different distance points from the projection radius of the crown,being:P1=one-third of the crown projection radius length;P2=two-thirds of the crown projection radius length;P3=extremity of the crown projection radius;P4=one and a half times the maximum crown projection radius length.Soil samples were collected at each point at depths of 0-0.10,0.10-0.20 and 0.20-0.40 m.Organic carbon and nitrogen contents were evaluated and the C/N ratio was calculated.The baru trees influenced the soil organic and carbon contents in the areas under their canopy.The organic carbon and nitrogen contents were higher in relation to the tree trunk(P1)and also in the most superficial layer of the soil(0-0.10 m).The C/N ratio was higher outside the tree canopy and in the deeper layer.
文摘Acacia seyal is a leguminous plant that plays an important role in the ecosystem of Sahelian zone by producing gum, wood and fodder. The growth of A. seyal is subject to many constraints as salinity which can affect the development of this tree. Therefore, soil microorganisms can help A. seyal to better tolerate the effects of negative environmental stresses. The contribution of arbuscular mycorrhizal fungi (AMF) to the salt tolerance of A. seyal, was evaluated by testing the effects of eight different arbuscular mycorrhizal fungi (AMF) isolates in the performance of A. seyal seedlings subjected to different levels of salinity (0, 340 and 680 mM). The results based on growth parameters of shoot and root parts, shoot mineral N, P, K and Na content as well as survival rates and mycorrhization showed that AMF improved mineral nutrition of A. seyal seedlings during salt stress. The combination between AMF and salinity provided evidence that the efficiency of AMF isolates were variable in improving mineral nutrition and mortality rate for A. seyal seedlings related to the level of salt stress. However, the effects of inoculation were variable depending to the AMF isolate associated with seedlings and the level of salinity, suggesting that interactions between plants and AMF can be modulated by both AMF diversity and the type and level of abiotic factors. Rhizophagus intraradices was more efficient at 680 mM NaCl in plant growth and mineral uptake while Glomus deserticola did not promote a better plant development than most of the other species inoculated to seedlings.
文摘To better understand the effects of direct sowing under mulch-based cropping system (DMC) in Burkina Faso’s cotton production systems, randomized blocks of Fisher experimental design were implemented at Farako-B<span style="white-space:nowrap;">a</span> research station from 2010 to 2019. The study was conducted on lixisoil to evaluate DMC effects on biomass production, crops yields and soil chemical properties in a maize and cotton rotation system associated with cover crop. Conventional tillage and direct seeding without cover crop were compared to DMC under <em>B</em>. <em>ruziziensis</em> (GERM. & EVRARD), DMC under <em>B</em>. <em>ruziziensis</em> + <em>M</em><em>.</em> <em>cochinchinensis</em> mulch and DMC under <em>C. juncea</em> (L.) mulch used in association with maize. Biomass production, crop yields and soil chemistry were evaluated. Results showed that over 10 years, no-till with or without a cover crop provided cotton seed and maize yields that were statistically equivalent to the tillage commonly practiced by farmers. Cover crop has allowed increasing the biomass production compared to Conventional Tillage and Direct Seeding. Maize yield has not varied significantly with the cover crop. After 10 years of maize and cotton rotation, the improvement raised from +27% to +38% for organic matter and from +15% to +29% for nitrogen with DMC including legumes such as <em>M. cochinchinensis</em> and <em>C. juncea</em> compared to Conventional Tillage on 0 - 5 cm depth. No significant differences were found on soil pH like P<sub>2</sub>O<sub>5</sub> and K<sub>2</sub>O content. Although DMC with <em>C. juncea</em> used as cover crop did not provide the best biomass production, it contributes to increase nitrogen and organic matter and presents better mineral balances in 10 years of rotation. The 5 - 10 cm and 10 - 20 cm were little influenced by DMC systems.
文摘The investigation was conducted to determine physiological criteria of early selection for salt tolerant leguminous plants. Plants were subjected to 5 levels of salt stress at the roots (0, 50, 100,150 and 200 mM NaCI). Results showed that sodium chloride had an underrating effect on growth of stems and seed germination of the species studied. The germination rates of seeds of Glycine max and Phaseolus vulgaris (sensitive glyeophytes) were affected from 3 g/L of NaCl, with critical thresholds at 9 and 12 g/L respectively. In contrast, critical thresholds with Mucunapoggei (facultative halophyte), Vigna unguiculata (moderately tolerant glycophyte) and P. adenanthus (natural halophyte) was found to be above 21 g/L. The reduction of stems growth rate were not significant in P. adenanthus whereas in M. poggei and V. unguiculata this inhibition was observed just when nutritive solutions were enriched with 200 mM. The lipid contents were reduced in all the species under salt stress, whereas proteins and proline contents in the leaves were substantially increased in tolerant species (M. poggei, P. adenanthus and V. unguiculata). In contrast, proteins and leaf proline contents were negatively affected by salt concentration to G. max and P. vulgaris. Seed germination, proteins and proline could be used as physiological criteria of early selection for salt tolerant leguminous plants.
基金supported by China Postdoctoral Science Foundation(No.2023M741742)the National Key R&D Program of China(No.2023YFD1501600)+1 种基金Jiangsu Funding Program for Excellent Postdoctoral Talent,China(No.2023ZB122)the National Natural Science Foundation of China(No.32371626)。
文摘Plant roots and their associated mycorrhizal fungi critically mediate the decomposition of soil organic carbon(C),but the general patterns of their impacts over a broad geographical range and the primary mediating factors remain unclear.Based on a synthesis of 596 paired observations from both field and greenhouse experiments,we found that living roots and/or mycorrhizal fungi increased organic C decomposition by 30.9%,but low soil nitrogen(N)availability(i.e.,high soil C:N ratio)critically mitigated this promotion effect.In addition,the positive effects of living roots and/or mycorrhizal fungi on organic C decomposition were higher under herbaceous and leguminous plants than under woody and non-leguminous plants,respectively.Surprisingly,there was no significant difference between arbuscular mycorrhizal fungi and ectomycorrhizal fungi in their effects on organic C decomposition.Furthermore,roots and/or mycorrhizal fungi significantly enhanced the decomposition of leaf litter but not root litter.These findings advance our understanding of how roots and their symbiotic fungi modulate soil C dynamics in the rhizosphere or mycorrhizosphere and may help improve predictions of soil global C balance under a changing climate.
基金This study was supported by Center for Ecological Research,Kyoto University,a Joint Usage/Research Center,and financially supported by the Japan Society for the Promotion of Science(JSPS)KAKENHI(Grant numbers 24228007,17H06171,and 19J14572).The authors have no relevant financial or non-financial interests to disclose.
文摘High nitrate leaching has been observed from the O horizons of some tropical forests;however,the drivers of high nitrate production(active nitrification)in these O horizons have not yet been identified.This study investigated the drivers of active nitrification in the O horizon of tropical forest soils by focusing on two of the most widely recognized controlling factors of nitrification,total N,and pH.We collected mineral and O horizons from eight tropical forests in Cameroon,Indonesia,and Malaysia and measured gross nitrification rates.Some O horizons showed significantly higher gross nitrification rates than mineral horizons,indicating that these O horizons have a high potential for nitrification.Gross nitrification rates in the O horizons were positively correlated with both total N and pH,and the chemical properties(e.g.,total content of N,P,and base cations)were intercorrelated.These correlations suggested that the underlying driver of nitrification in the O horizon was nutrient richness in the litter.Results also indicated a threshold of gross nitrification rates around pH values of 5.5–6.0.We elucidate that active nitrification and subsequent high nitrate leaching from the O horizon could be driven by nutrient-rich litter,possibly derived from soil fertility and tree species.