A. Swan, Laura Goward, J. Hunt, J. Kirkegaard, M. Peoples
ABSTRACT Context. Herbicide-resistant annual ryegrass (Lolium rigidum; ARG) is a major weed of commercial significance globally, including no-till wheat-based production systems in south-eastern Australia. Aims. To compare the cost-effectiveness of different crop sequences and intensities of weed management to control ARG in rainfed grain production. Methods. Two on-farm studies in southern New South Wales, Australia, compared the effect of combinations of 3-year crop-sequence options (continuous wheat, 1- or 2-years of break crops), conservative or aggressive weed-control measures, hay cuts, legume brown manure (BM), and/or weed-free winter fallow on in-crop ARG infestations and soil seedbanks. Gross margins were calculated for each combination of treatments to compare system economic performance. Key results. Double-breaks consisting of two consecutive broadleaf crops, or canola–cereal hay, were frequently the most profitable and effective ARG control strategies. Single canola or lupin crops, BM, cereal hay, and fallow all significantly reduced subsequent in-crop ARG and seedbank numbers compared with continuous wheat. Aggressive in-crop control measures in wheat were more expensive than those applied to break crops. Gains in ARG control could be lost by a single year of poor weed control. Conclusions. High levels of control (>95%) over three consecutive seasons are required to reduce ARG seedbanks, and this is most cost-effectively achieved with diverse crop sequences. Implications. Farmers with high populations of ARG can reduce seedbanks by growing three crops sequentially that achieve complete weed seed control. This must be followed with ongoing high levels of control in subsequent years to keep ARG seedbanks low.
{"title":"Diverse systems and strategies to cost-effectively manage herbicide-resistant annual ryegrass (Lolium rigidum) in no-till wheat (Triticum aestivum)-based cropping sequences in south-eastern Australia","authors":"A. Swan, Laura Goward, J. Hunt, J. Kirkegaard, M. Peoples","doi":"10.1071/CP22370","DOIUrl":"https://doi.org/10.1071/CP22370","url":null,"abstract":"ABSTRACT Context. Herbicide-resistant annual ryegrass (Lolium rigidum; ARG) is a major weed of commercial significance globally, including no-till wheat-based production systems in south-eastern Australia. Aims. To compare the cost-effectiveness of different crop sequences and intensities of weed management to control ARG in rainfed grain production. Methods. Two on-farm studies in southern New South Wales, Australia, compared the effect of combinations of 3-year crop-sequence options (continuous wheat, 1- or 2-years of break crops), conservative or aggressive weed-control measures, hay cuts, legume brown manure (BM), and/or weed-free winter fallow on in-crop ARG infestations and soil seedbanks. Gross margins were calculated for each combination of treatments to compare system economic performance. Key results. Double-breaks consisting of two consecutive broadleaf crops, or canola–cereal hay, were frequently the most profitable and effective ARG control strategies. Single canola or lupin crops, BM, cereal hay, and fallow all significantly reduced subsequent in-crop ARG and seedbank numbers compared with continuous wheat. Aggressive in-crop control measures in wheat were more expensive than those applied to break crops. Gains in ARG control could be lost by a single year of poor weed control. Conclusions. High levels of control (>95%) over three consecutive seasons are required to reduce ARG seedbanks, and this is most cost-effectively achieved with diverse crop sequences. Implications. Farmers with high populations of ARG can reduce seedbanks by growing three crops sequentially that achieve complete weed seed control. This must be followed with ongoing high levels of control in subsequent years to keep ARG seedbanks low.","PeriodicalId":51237,"journal":{"name":"Crop & Pasture Science","volume":"74 1","pages":"809 - 827"},"PeriodicalIF":1.9,"publicationDate":"2023-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44169592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
W. Badgery, Guangdi D. Li, A. Simmons, Jennifer Wood, Rowan W. Smith, D. Peck, L. Ingram, Z. Durmic, A. Cowie, A. Humphries, P. Hutton, Emma Winslow, P. Vercoe, R. Eckard
ABSTRACT In Australia, 71% of agricultural greenhouse gas (GHG) emissions are enteric methane (CH4), mostly produced by grazing sheep and cattle. Temperate low CH4 yielding legumes and herbs can mitigate enteric CH4 production, but system-level GHG emissions need to be considered. The aims of the study were to: (1) devise a framework to assess GHG reductions when introducing low CH4 yielding species; (2) assess mechanisms of CH4 reduction in temperate legume and herb species for Australia; (3) use a case study to demonstrate expected changes to system-level GHG emissions with the introduction of low CH4 yielding legumes; and (4) identify knowledge gaps and research priorities. Results demonstrate lowering emissions intensity (kg CO2-equivalent/kg product) is crucial to mitigate GHG emissions, but livestock productivity is also important. Several pasture species have anti-methanogenic properties, but responses often vary considerably. Of the species investigated biserrula (Biserrula pelecinus) has great potential to reduce enteric CH4 emissions, but in a case study its emission intensity was similar to subterranean clover (Trifolium subterraneum) but higher than lucerne (Medicago sativa). We conclude that there are temperate legumes and herbs with anti-methanogenic properties, and/or high productivity that could reduce total CH4 emissions and emissions intensity of ruminant livestock production. There is also great diversity in some plant genotypes that can be exploited, and this will be aided by more detailed understanding of plant secondary compounds associated with CH4 reduction. This review suggests an opportunity to formulate pasture species mixtures to achieve reduced CH4 emissions with greater or equal livestock production.
{"title":"Reducing enteric methane of ruminants in Australian grazing systems – a review of the role for temperate legumes and herbs","authors":"W. Badgery, Guangdi D. Li, A. Simmons, Jennifer Wood, Rowan W. Smith, D. Peck, L. Ingram, Z. Durmic, A. Cowie, A. Humphries, P. Hutton, Emma Winslow, P. Vercoe, R. Eckard","doi":"10.1071/CP22299","DOIUrl":"https://doi.org/10.1071/CP22299","url":null,"abstract":"ABSTRACT In Australia, 71% of agricultural greenhouse gas (GHG) emissions are enteric methane (CH4), mostly produced by grazing sheep and cattle. Temperate low CH4 yielding legumes and herbs can mitigate enteric CH4 production, but system-level GHG emissions need to be considered. The aims of the study were to: (1) devise a framework to assess GHG reductions when introducing low CH4 yielding species; (2) assess mechanisms of CH4 reduction in temperate legume and herb species for Australia; (3) use a case study to demonstrate expected changes to system-level GHG emissions with the introduction of low CH4 yielding legumes; and (4) identify knowledge gaps and research priorities. Results demonstrate lowering emissions intensity (kg CO2-equivalent/kg product) is crucial to mitigate GHG emissions, but livestock productivity is also important. Several pasture species have anti-methanogenic properties, but responses often vary considerably. Of the species investigated biserrula (Biserrula pelecinus) has great potential to reduce enteric CH4 emissions, but in a case study its emission intensity was similar to subterranean clover (Trifolium subterraneum) but higher than lucerne (Medicago sativa). We conclude that there are temperate legumes and herbs with anti-methanogenic properties, and/or high productivity that could reduce total CH4 emissions and emissions intensity of ruminant livestock production. There is also great diversity in some plant genotypes that can be exploited, and this will be aided by more detailed understanding of plant secondary compounds associated with CH4 reduction. This review suggests an opportunity to formulate pasture species mixtures to achieve reduced CH4 emissions with greater or equal livestock production.","PeriodicalId":51237,"journal":{"name":"Crop & Pasture Science","volume":"74 1","pages":"661 - 679"},"PeriodicalIF":1.9,"publicationDate":"2023-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47968440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Context. Banana production in Australia is in three primary sub-regions within tropical North Queensland and the industry faces a variety of challenges including costs of production, disease and pests, and environmental impacts. The range of soil characteristics and banana leaf nutrient status on banana farms has not previously been systematically described. This knowledge gap makes it difficult to adapt research, management recommendations, and regulations to the needs of the three primary growing sub-regions. Aims. In this work, we aimed to identify key soil factors that differentiate growing sub-regions, and provide context for future research and industry regulation. Methods. We characterised soil and banana leaf samples from 28 banana farms on soil types accounting for >85% of Australia’s banana production. Key results. Variation in soil properties and leaf nutrient concentrations were driven largely by site- (principal component 1 in both cases) and management-related variables (principal component 2 in both cases). Management-related foliar nutrient concentrations did not differ between regions despite differences in the associated soil variables. The most important site characteristics appeared to be soil parent material and climate. The Mareeba sub-region has basaltic soils, low rainfall and temperature, whereas the other two sub-regions are hotter, wetter and have a variety of soil parent materials. Leaf nitrogen concentrations were mostly below the regulated limit for additional nitrogen fertiliser application. Implications. Our findings can facilitate sub-region-specific site selection for research, extension, and monitoring and more targeted regulation of banana production- and environment-related issues.
{"title":"Soil physicochemical characteristics and leaf nutrient contents on banana farms of North Queensland, Australia","authors":"R. Orr, T. Northfield, A. Pattison, P. N. Nelson","doi":"10.1071/CP22306","DOIUrl":"https://doi.org/10.1071/CP22306","url":null,"abstract":"Abstract Context. Banana production in Australia is in three primary sub-regions within tropical North Queensland and the industry faces a variety of challenges including costs of production, disease and pests, and environmental impacts. The range of soil characteristics and banana leaf nutrient status on banana farms has not previously been systematically described. This knowledge gap makes it difficult to adapt research, management recommendations, and regulations to the needs of the three primary growing sub-regions. Aims. In this work, we aimed to identify key soil factors that differentiate growing sub-regions, and provide context for future research and industry regulation. Methods. We characterised soil and banana leaf samples from 28 banana farms on soil types accounting for >85% of Australia’s banana production. Key results. Variation in soil properties and leaf nutrient concentrations were driven largely by site- (principal component 1 in both cases) and management-related variables (principal component 2 in both cases). Management-related foliar nutrient concentrations did not differ between regions despite differences in the associated soil variables. The most important site characteristics appeared to be soil parent material and climate. The Mareeba sub-region has basaltic soils, low rainfall and temperature, whereas the other two sub-regions are hotter, wetter and have a variety of soil parent materials. Leaf nitrogen concentrations were mostly below the regulated limit for additional nitrogen fertiliser application. Implications. Our findings can facilitate sub-region-specific site selection for research, extension, and monitoring and more targeted regulation of banana production- and environment-related issues.","PeriodicalId":51237,"journal":{"name":"Crop & Pasture Science","volume":"74 1","pages":"483 - 493"},"PeriodicalIF":1.9,"publicationDate":"2023-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46715779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lucélia de Cássia Rodrigues de Brito, H. A. Souza, R. B. A. Araújo Neto, D. M. P. Azevedo, E. Sagrilo, R. F. Vogado, Suzane Pereira Carvalho, A. Ferreira, M. Cavigelli
Abstract Context. Intercropping maize with tropical forages is known to provide multiple benefits for the agricultural sustainability in the Brazilian savanna. Despite that, more studies are needed to define strategies to improve soil quality and increase crop yield of subsequent crops. Aims. This study aimed to evaluate the impacts of cultivating maize in monoculture or in double- and triple-intercropping with brachiaria and crotalaria on the chemical and microbiological attributes of soil, nutritional status of soybean, and the productivity of soybean and millet in succession in the cerrado of eastern Maranhão. Methods. The intercropping systems implemented in 2017 were as follows: maize (Zea mays) + Urochloa ruzizienses (brachiaria); maize + Crotalaria juncea (crotalaria); maize + brachiaria + crotalaria; and monoculture maize as a control. In 2018 and 2019, soybean and millet were cultivated on the same plots. Key results. The triple-intercropping promoted immediate improvement in the biological and chemical attributes of the soil, especially when compared with monoculture maize. Intercropping maize with brachiaria, with or without crotalaria, increased soybean productivity by 21% and millet by 44% in the subsequent year, compared with monoculture maize system. Intercropping maize with brachiaria, with or without crotalaria, increased the leaf concentrations of nitrogen, potassium, magnesium, and sulfur of the subsequent soybean crop, suggesting improved nutrient cycling with intercropped forages. Conclusions. Intercropping maize + forage, especially brachiaria, can be recommended for crop rotation and succession systems in the Brazilian savanna. Implications. These results quantified the benefits of crop rotation following intercropping with maize and forage, which can be an alternative for farmers in the Brazilian savanna.
{"title":"Improved soil fertility, plant nutrition and grain yield of soybean and millet following maize intercropped with forage grasses and crotalaria in the Brazilian savanna","authors":"Lucélia de Cássia Rodrigues de Brito, H. A. Souza, R. B. A. Araújo Neto, D. M. P. Azevedo, E. Sagrilo, R. F. Vogado, Suzane Pereira Carvalho, A. Ferreira, M. Cavigelli","doi":"10.1071/CP22251","DOIUrl":"https://doi.org/10.1071/CP22251","url":null,"abstract":"Abstract Context. Intercropping maize with tropical forages is known to provide multiple benefits for the agricultural sustainability in the Brazilian savanna. Despite that, more studies are needed to define strategies to improve soil quality and increase crop yield of subsequent crops. Aims. This study aimed to evaluate the impacts of cultivating maize in monoculture or in double- and triple-intercropping with brachiaria and crotalaria on the chemical and microbiological attributes of soil, nutritional status of soybean, and the productivity of soybean and millet in succession in the cerrado of eastern Maranhão. Methods. The intercropping systems implemented in 2017 were as follows: maize (Zea mays) + Urochloa ruzizienses (brachiaria); maize + Crotalaria juncea (crotalaria); maize + brachiaria + crotalaria; and monoculture maize as a control. In 2018 and 2019, soybean and millet were cultivated on the same plots. Key results. The triple-intercropping promoted immediate improvement in the biological and chemical attributes of the soil, especially when compared with monoculture maize. Intercropping maize with brachiaria, with or without crotalaria, increased soybean productivity by 21% and millet by 44% in the subsequent year, compared with monoculture maize system. Intercropping maize with brachiaria, with or without crotalaria, increased the leaf concentrations of nitrogen, potassium, magnesium, and sulfur of the subsequent soybean crop, suggesting improved nutrient cycling with intercropped forages. Conclusions. Intercropping maize + forage, especially brachiaria, can be recommended for crop rotation and succession systems in the Brazilian savanna. Implications. These results quantified the benefits of crop rotation following intercropping with maize and forage, which can be an alternative for farmers in the Brazilian savanna.","PeriodicalId":51237,"journal":{"name":"Crop & Pasture Science","volume":"74 1","pages":"438 - 448"},"PeriodicalIF":1.9,"publicationDate":"2023-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41502602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Syed Mohsan Raza Shah, S. Fatima, M. Hameed, Sana Basharat, M. Ahmad, F. Ahmad, A. Asghar, Majid Anwar, Fozia Yasmin, Muhammad Ashraf, Jazab Shafqat
Abstract Context. Allelopathy is recognised as a potential technology to control weeds, and could also be a suitable approach for enhancement of crop yield. Aims. The study was conducted to investigate the allelopathic role of Averrhoa carambola leaf extract on growth, anatomical and physiological features of three wheat lines, namely 3094, 7076 and A2011. Methods. Three dilutions i.e. 0% (control), 15% and 30% of the leaf aqueous extract were applied at 15 day intervals (total five applications) on wheat lines until maturity. Key results. All wheat lines showed differential behaviour to allelochemicals of A. carambola leaf extract. Increased root area was accompanied by a high proportion of storage parenchyma tissues and enlarged vascular bundles in line 3094. Disintegration of root cortical parenchyma and complete transformation of chlorenchyma into sclerenchyma in stem was recorded in all wheat lines, particularly at the highest concentration of leaf extract. Line 7076 showed very different behaviour, as it possessed a proportionally enlarged root cortex, enlarged stem vascular bundles and increased leaf thickness, primarily at the highest concentration of leaf extract. Line A2011 was relatively more sensitive, indicating a significant reduction (P < 0.05) in root and stem area and deformed leaves. Conclusions. A low concentration (15%) of leaf extract promoted growth and development, whereas a higher concentration caused significant reduction in growth and anatomical attributes. Implications. A lower dose of Averrhoa leaf extract promoted growth and development in all wheat lines, and hence can be used as a growth promoter. A higher concentration is important for eradicating unwanted plants.
{"title":"Allelochemicals extract of star fruit (Averrhoa carambola L.) modulates wheat growth through alterations in anatomical architecture","authors":"Syed Mohsan Raza Shah, S. Fatima, M. Hameed, Sana Basharat, M. Ahmad, F. Ahmad, A. Asghar, Majid Anwar, Fozia Yasmin, Muhammad Ashraf, Jazab Shafqat","doi":"10.1071/CP22373","DOIUrl":"https://doi.org/10.1071/CP22373","url":null,"abstract":"Abstract Context. Allelopathy is recognised as a potential technology to control weeds, and could also be a suitable approach for enhancement of crop yield. Aims. The study was conducted to investigate the allelopathic role of Averrhoa carambola leaf extract on growth, anatomical and physiological features of three wheat lines, namely 3094, 7076 and A2011. Methods. Three dilutions i.e. 0% (control), 15% and 30% of the leaf aqueous extract were applied at 15 day intervals (total five applications) on wheat lines until maturity. Key results. All wheat lines showed differential behaviour to allelochemicals of A. carambola leaf extract. Increased root area was accompanied by a high proportion of storage parenchyma tissues and enlarged vascular bundles in line 3094. Disintegration of root cortical parenchyma and complete transformation of chlorenchyma into sclerenchyma in stem was recorded in all wheat lines, particularly at the highest concentration of leaf extract. Line 7076 showed very different behaviour, as it possessed a proportionally enlarged root cortex, enlarged stem vascular bundles and increased leaf thickness, primarily at the highest concentration of leaf extract. Line A2011 was relatively more sensitive, indicating a significant reduction (P < 0.05) in root and stem area and deformed leaves. Conclusions. A low concentration (15%) of leaf extract promoted growth and development, whereas a higher concentration caused significant reduction in growth and anatomical attributes. Implications. A lower dose of Averrhoa leaf extract promoted growth and development in all wheat lines, and hence can be used as a growth promoter. A higher concentration is important for eradicating unwanted plants.","PeriodicalId":51237,"journal":{"name":"Crop & Pasture Science","volume":"74 1","pages":"423 - 437"},"PeriodicalIF":1.9,"publicationDate":"2023-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46145896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Context. Plant secondary metabolites are of increasing interest for agriculture due to their diverse beneficial ecological functions. The forage crop white clover (Trifolim repens L.) has been intensively studied for its heritable polymorphism in the production of hydrogen cyanide (HCN), a toxic defense phytochemical. In fodder production, white clover accessions are selected for biomass production, whereby HCN production is an unwanted trait. Aim. Although white clover is a legume crop species of global importance, little is known about the linkage between cyanogenesis and growth traits, in particular in combination with resistance-related phytochemicals, such as flavonoids. We aimed to identify differences in biomass production, estimated leaf flavonoid content, and trait correlations in cyanogenic (HCN-producing) and acyanogenic (not HCN-producing) individuals and accessions of white clover. Methods. We analysed 51 white clover accessions from a German germplasm collection for variability in selected traits: cyanogenesis as equivalent electrode potential, estimated leaf flavonoid content, root and shoot production, leaf area, specific leaf area, and number of leaves produced. Key results. Most accessions considered as cyanogenic were heterogeneous for HCN production. Chemical–morphological trait correlations differed between cyanogenic and acyanogenic plants. Acyanogenic individuals and accessions produced more and larger leaves compared to cyanogenic ones. Within cyanogenic accessions, the higher the HCN level of a plant, the fewer but larger leaves were produced. Conclusions. Our results highlight the variation in HCN production within the selected accessions, which calls for a consistent approach for cyanogenesis-based categorisation. Implication. This study demonstrates the potential of combining phytochemical traits with biomass production in white clover when selecting material in a breeding program.
{"title":"Effects of cyanogenesis on morphology and estimated leaf flavonoid content in 51 white clover accessions","authors":"Jennifer Gabriel, N. V. van Dam, Henriette Uthe","doi":"10.1071/CP22140","DOIUrl":"https://doi.org/10.1071/CP22140","url":null,"abstract":"Abstract Context. Plant secondary metabolites are of increasing interest for agriculture due to their diverse beneficial ecological functions. The forage crop white clover (Trifolim repens L.) has been intensively studied for its heritable polymorphism in the production of hydrogen cyanide (HCN), a toxic defense phytochemical. In fodder production, white clover accessions are selected for biomass production, whereby HCN production is an unwanted trait. Aim. Although white clover is a legume crop species of global importance, little is known about the linkage between cyanogenesis and growth traits, in particular in combination with resistance-related phytochemicals, such as flavonoids. We aimed to identify differences in biomass production, estimated leaf flavonoid content, and trait correlations in cyanogenic (HCN-producing) and acyanogenic (not HCN-producing) individuals and accessions of white clover. Methods. We analysed 51 white clover accessions from a German germplasm collection for variability in selected traits: cyanogenesis as equivalent electrode potential, estimated leaf flavonoid content, root and shoot production, leaf area, specific leaf area, and number of leaves produced. Key results. Most accessions considered as cyanogenic were heterogeneous for HCN production. Chemical–morphological trait correlations differed between cyanogenic and acyanogenic plants. Acyanogenic individuals and accessions produced more and larger leaves compared to cyanogenic ones. Within cyanogenic accessions, the higher the HCN level of a plant, the fewer but larger leaves were produced. Conclusions. Our results highlight the variation in HCN production within the selected accessions, which calls for a consistent approach for cyanogenesis-based categorisation. Implication. This study demonstrates the potential of combining phytochemical traits with biomass production in white clover when selecting material in a breeding program.","PeriodicalId":51237,"journal":{"name":"Crop & Pasture Science","volume":"74 1","pages":"494 - 506"},"PeriodicalIF":1.9,"publicationDate":"2023-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44204455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Muralidhara Bharamappanavara, Manoj Appaiah Chikkahosahalli, B. Patil, Ajitha Vijjeswarapu, M. S. Anantha, Lokesha Ramappa, J. Diwan, J. Nidagundi, Umesh Rangappa Mathada, Suma Chandrasekhara Talagunda, Lokesh Yellaiah Guddalahalli, Rajanna Byanna, S. Rathod, R. Sundaram, L. V. Subbarao, Mahender Kumar Rapolu, C. Gireesh
ABSTRACT Context. Broadening the gene pool of staple food crops by incorporating desirable genes from wild/relative species is way to achieve higher genetic gains. The African rice species Oryza glaberrima Steud. is a source of genes for genetic improvement of Oryza sativa L. to various biotic and abiotic stresses. Aim. The study was undertaken to identify genomic regions associated with yield and yield-related traits in interspecific backcross mapping populations derived from variety IR64 (O. sativa indica) × O. glaberrima. Methods. The BC1F2 and BC1F2:3 populations were phenotyped for days to 50% flowering, plant height, number of tillers, number of productive tillers, panicle length, spikelet fertility and grain yield under irrigated conditions. The BC1F2 population was genotyped with 99 genome-wide polymorphic SSR markers. Quantitative trait loci (QTLs) associated with yield-enhancing traits were identified through single marker analysis. Key results. Significant genetic variability was observed with moderate to high heritability in mapping populations. Genotyping revealed the presence of segregation distortion and skewed genome composition. Single marker analysis identified 20 QTLs linked to the studied traits. A QTL linked to grain yield, qGY-4.1, derived from O. glaberrima was found in both populations with high phenotypic variance. The chromosome region around marker RM510 was identified as a QTL hotspot and putative candidate genes were identified. Conclusions. Our study demonstrates that O. glaberrima can serve as a valuable genetic resource for genetic improvement of yield-enhancing traits in O. sativa cultivars. Implications The identified QTLs regions can be employed in molecular breeding. The promising introgression lines identified can be used as pre-breeding lines in future breeding programs.
抽象的上下文。通过纳入野生/相对物种的优良基因来扩大主粮作物基因库是实现更高遗传收益的途径。非洲稻种glaberrima Steud。是水稻抗各种生物和非生物胁迫遗传改良的基因来源。的目标。本研究旨在鉴定品种IR64 (O. sativa indica) × O. glaberrima种间回交定位群体中与产量和产量相关性状相关的基因组区域。方法。在灌溉条件下,对BC1F2和BC1F2:3群体的开花天数~ 50%、株高、分蘖数、有效分蘖数、穗长、小穗育性和籽粒产量进行表型分析。用99个全基因组多态性SSR标记对BC1F2群体进行基因分型。通过单标记分析,鉴定出与增产性状相关的数量性状位点。关键的结果。在作图群体中观察到显著的遗传变异,遗传力中等至高。基因分型显示存在分离扭曲和基因组组成偏斜。单标记分析鉴定出与所研究性状相关的20个qtl。在两个表型变异较高的群体中均发现了一个与籽粒产量相关的QTL qGY-4.1。标记RM510周围的染色体区域被确定为QTL热点,并确定了可能的候选基因。结论。本研究结果表明,光斑草可作为一种宝贵的遗传资源,用于玉米品种增产性状的遗传改良。意义所鉴定的qtl区域可用于分子育种。鉴定出的有潜力的渐渗系可作为未来育种计划中的预育种系。
{"title":"Genetic analysis and identification of QTLs associated with yield-enhancing traits in Oryza sativa IR64 × Oryza glaberrima interspecific backcross populations","authors":"Muralidhara Bharamappanavara, Manoj Appaiah Chikkahosahalli, B. Patil, Ajitha Vijjeswarapu, M. S. Anantha, Lokesha Ramappa, J. Diwan, J. Nidagundi, Umesh Rangappa Mathada, Suma Chandrasekhara Talagunda, Lokesh Yellaiah Guddalahalli, Rajanna Byanna, S. Rathod, R. Sundaram, L. V. Subbarao, Mahender Kumar Rapolu, C. Gireesh","doi":"10.1071/CP22105","DOIUrl":"https://doi.org/10.1071/CP22105","url":null,"abstract":"ABSTRACT Context. Broadening the gene pool of staple food crops by incorporating desirable genes from wild/relative species is way to achieve higher genetic gains. The African rice species Oryza glaberrima Steud. is a source of genes for genetic improvement of Oryza sativa L. to various biotic and abiotic stresses. Aim. The study was undertaken to identify genomic regions associated with yield and yield-related traits in interspecific backcross mapping populations derived from variety IR64 (O. sativa indica) × O. glaberrima. Methods. The BC1F2 and BC1F2:3 populations were phenotyped for days to 50% flowering, plant height, number of tillers, number of productive tillers, panicle length, spikelet fertility and grain yield under irrigated conditions. The BC1F2 population was genotyped with 99 genome-wide polymorphic SSR markers. Quantitative trait loci (QTLs) associated with yield-enhancing traits were identified through single marker analysis. Key results. Significant genetic variability was observed with moderate to high heritability in mapping populations. Genotyping revealed the presence of segregation distortion and skewed genome composition. Single marker analysis identified 20 QTLs linked to the studied traits. A QTL linked to grain yield, qGY-4.1, derived from O. glaberrima was found in both populations with high phenotypic variance. The chromosome region around marker RM510 was identified as a QTL hotspot and putative candidate genes were identified. Conclusions. Our study demonstrates that O. glaberrima can serve as a valuable genetic resource for genetic improvement of yield-enhancing traits in O. sativa cultivars. Implications The identified QTLs regions can be employed in molecular breeding. The promising introgression lines identified can be used as pre-breeding lines in future breeding programs.","PeriodicalId":51237,"journal":{"name":"Crop & Pasture Science","volume":"74 1","pages":"1023 - 1036"},"PeriodicalIF":1.9,"publicationDate":"2023-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44020741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ABSTRACT Context. Post-anthesis heat stress is a major concern for wheat. Stay-green (SG) can serve as a crucial marker for plant adaptation to it. Though genetic resources provide an invaluable gene pool for crop breeding, collections are still uncharacterised and their potential is yet to be explored. Aim. This study was planned to characterise and evaluate wheat genetic resources, including wild germplasm, for heat stress tolerance using SG traits as selection criteria. Methods. Experiment was conducted with thirty wheat genotypes under late and very late sown environments for 2 years. Genotypes were assessed for SG traits like Normalised Difference Vegetation Index (NDVI), Soil Plant Analysis Development Chlorophyll Meter Reading (SCMR), Leaf Senescence Rate (LSR), chlorophyll fluorescence (Fv/Fm), canopy temperature (CT), phenological traits, morphological traits, yield and its attributes; and characterised into three categories viz., slow senescing, intermediate senescing and fast senescing, based on their rate of senescence. Key results. Results indicate that slow-senescing genotypes had a significantly higher NDVI, SCMR and yield as compared to fast-senescing genotypes. NDVI, SCMR, Fv/Fm, days to heading, days to anthesis, days to maturity, grain weight per spike, 100-grain weight and biomass were significantly positively correlated whereas LSR and CT were significantly negatively correlated with grain yield. From the principal component analysis studies, it was revealed that genotypes with a high SCMR, a low LSR, and a high grain yield were placed together as SG genotypes. Conclusions. This study confirms that genotypes with SG traits performed better under heat stress. Implications. From the wild, genotypes HTW 11 (W), HTW 67 (W) and HTW 6 (W) can be utilised for heat tolerance breedings.
{"title":"Characterisation and evaluation of wheat genetic resources for heat stress tolerance using stay-green traits","authors":"A. Soni, R. Munjal","doi":"10.1071/CP22119","DOIUrl":"https://doi.org/10.1071/CP22119","url":null,"abstract":"ABSTRACT Context. Post-anthesis heat stress is a major concern for wheat. Stay-green (SG) can serve as a crucial marker for plant adaptation to it. Though genetic resources provide an invaluable gene pool for crop breeding, collections are still uncharacterised and their potential is yet to be explored. Aim. This study was planned to characterise and evaluate wheat genetic resources, including wild germplasm, for heat stress tolerance using SG traits as selection criteria. Methods. Experiment was conducted with thirty wheat genotypes under late and very late sown environments for 2 years. Genotypes were assessed for SG traits like Normalised Difference Vegetation Index (NDVI), Soil Plant Analysis Development Chlorophyll Meter Reading (SCMR), Leaf Senescence Rate (LSR), chlorophyll fluorescence (Fv/Fm), canopy temperature (CT), phenological traits, morphological traits, yield and its attributes; and characterised into three categories viz., slow senescing, intermediate senescing and fast senescing, based on their rate of senescence. Key results. Results indicate that slow-senescing genotypes had a significantly higher NDVI, SCMR and yield as compared to fast-senescing genotypes. NDVI, SCMR, Fv/Fm, days to heading, days to anthesis, days to maturity, grain weight per spike, 100-grain weight and biomass were significantly positively correlated whereas LSR and CT were significantly negatively correlated with grain yield. From the principal component analysis studies, it was revealed that genotypes with a high SCMR, a low LSR, and a high grain yield were placed together as SG genotypes. Conclusions. This study confirms that genotypes with SG traits performed better under heat stress. Implications. From the wild, genotypes HTW 11 (W), HTW 67 (W) and HTW 6 (W) can be utilised for heat tolerance breedings.","PeriodicalId":51237,"journal":{"name":"Crop & Pasture Science","volume":"74 1","pages":"1037 - 1057"},"PeriodicalIF":1.9,"publicationDate":"2023-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47405545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Maneesha, Mondem Bhargavi, D. M. Withanawasam, Penumalli Shanthi, Madhavi L. Kommana, Keerthi Issa, Lavanya Kumari Padherla, Roja Veeraghattapu, Md. Aminul Islam, B. Tanti, Sudhakar Palagiri, L. R. Vemireddy
Abstract Context. Regular genetic monitoring of rice diversity provides informed direction for plant breeders when selecting parents in breeding programs. Aims. The investigation was conducted to assess the trends of decade-wise genetic diversity in popular Indian rice (Oryza sativa L.) genotypes. Methods. We screened 62 genotypes including popular rice varieties released from the 1970s to 2010s in India along with landraces, using gene-specific markers and some of the key yield and yield-contributing traits. Key results. Using gene-specific markers, genetic diversity has shown a downward trend from landraces to the 2010s. Qualitative analysis revealed that more alleles were present in landraces than released varieties. The disappearance of alleles was prominently observed in varieties released in the 1970s and even more so in the 2010s, which suggests that present-day cultivars are losing several valuable alleles of the key yield genes. Genetic diversity assessed using phenotypic data also exhibited a downward trend towards the 2010s. Molecular and phenotypic data on genetic diversity were used to group the rice genotypes, revealing that genotypes with common parents grouped together. Conclusions. Genetic diversity has shown a downward trend from landraces to the 2010s, as assessed using both gene-specific markers and phenotypic data, although with slight deviations among various decades. Implications. This study reinforces the fact that assessment of temporal trends in genetic diversity at regular intervals is warranted to meet future food demands while conserving on-farm crop diversity.
{"title":"Genetic monitoring of Indian rice (Oryza sativa) cultivars over decadal periods employing gene-specific markers and yield component traits","authors":"K. Maneesha, Mondem Bhargavi, D. M. Withanawasam, Penumalli Shanthi, Madhavi L. Kommana, Keerthi Issa, Lavanya Kumari Padherla, Roja Veeraghattapu, Md. Aminul Islam, B. Tanti, Sudhakar Palagiri, L. R. Vemireddy","doi":"10.1071/CP22240","DOIUrl":"https://doi.org/10.1071/CP22240","url":null,"abstract":"Abstract Context. Regular genetic monitoring of rice diversity provides informed direction for plant breeders when selecting parents in breeding programs. Aims. The investigation was conducted to assess the trends of decade-wise genetic diversity in popular Indian rice (Oryza sativa L.) genotypes. Methods. We screened 62 genotypes including popular rice varieties released from the 1970s to 2010s in India along with landraces, using gene-specific markers and some of the key yield and yield-contributing traits. Key results. Using gene-specific markers, genetic diversity has shown a downward trend from landraces to the 2010s. Qualitative analysis revealed that more alleles were present in landraces than released varieties. The disappearance of alleles was prominently observed in varieties released in the 1970s and even more so in the 2010s, which suggests that present-day cultivars are losing several valuable alleles of the key yield genes. Genetic diversity assessed using phenotypic data also exhibited a downward trend towards the 2010s. Molecular and phenotypic data on genetic diversity were used to group the rice genotypes, revealing that genotypes with common parents grouped together. Conclusions. Genetic diversity has shown a downward trend from landraces to the 2010s, as assessed using both gene-specific markers and phenotypic data, although with slight deviations among various decades. Implications. This study reinforces the fact that assessment of temporal trends in genetic diversity at regular intervals is warranted to meet future food demands while conserving on-farm crop diversity.","PeriodicalId":51237,"journal":{"name":"Crop & Pasture Science","volume":"74 1","pages":"393 - 404"},"PeriodicalIF":1.9,"publicationDate":"2023-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44687712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. J. Agüero, M. Acreche, S. Sühring, H. Bertero, R. N. Curti
{"title":"Genotype-dependent responses of Andean and Coastal quinoa to plant population density for yield and its physiological determinants in Northwest Argentina","authors":"J. J. Agüero, M. Acreche, S. Sühring, H. Bertero, R. N. Curti","doi":"10.1071/cp23040","DOIUrl":"https://doi.org/10.1071/cp23040","url":null,"abstract":"","PeriodicalId":51237,"journal":{"name":"Crop & Pasture Science","volume":"1 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58706181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}