As a woody grass,bamboo has special reproductive habits with an extremely long vegetative phase.Pleioblastus pygmaeus is a kind of ornamental dwarf bamboo species with high ecological and economic value in China.There...As a woody grass,bamboo has special reproductive habits with an extremely long vegetative phase.Pleioblastus pygmaeus is a kind of ornamental dwarf bamboo species with high ecological and economic value in China.There was no documentary record of the flowering of P.pygmaeus until 2015,which bloomed in the Bamboo Garden of Nanjing Forestry University.Generally,bamboo plants rarely bear fruit or have a low seed setting rate,but this species has a high seed production.This study explores developmental reasons using anatomical methods.The process of flower bud differentiation and a series of important reproductive development processes including anther wall development,microsporogenesis,megasporogenesis,male and female gametophyte development,and embryonic development were investigated sequentially.Each stamen contained three tetrasporangiate anthers and the development of anther wall was of Monocotyledonous type.The microspores finally matured into 3-celled pollen grains by two successive mitoses.The pistil was composed of three carpels,with an anatropous,tenuinucellate and bitegmic ovule in a single ovary.The formation of embryo sac belonged to Polygonum type.With three mitoses,functional megaspore developed into the embryo sac with eight nuclei within seven cells.The development of stamen and pistil was synchronous in the same floret.The development of embryo followed Grass type and the development of endosperm belonged to Nuclear type.The development of endosperm was earlier than that of embryo.The study enriches basic knowledge of reproductive biology of bamboo plants and is of great fundamental significance to furtherly explore flowering mechanism of P.pygmaeus and to cultivate bamboo plants sustainably.展开更多
The biological parameters of Macrolophus pygmaeus Rambur afler prolonged rearing in the absence of plant materials were compared with those of conventionally plant-reared predators. When eggs of Ephestia kuehniella Ze...The biological parameters of Macrolophus pygmaeus Rambur afler prolonged rearing in the absence of plant materials were compared with those of conventionally plant-reared predators. When eggs of Ephestia kuehniella Zeller were provided as food, developmental and reproductive fitness of M. pygmaeus reared for over 30 consecutive generations using artificial living and oviposition substrates was similar to that of predators kept on tobacco leaves. Plantless-reared fifth instars of the predator also had similar predation rates on second instars of the tobacco aphid, Myzus persicae nicotianae Blackman, as their peers maintained on plant materials. In a further experiment, predation on aphid prey by fifth instar M. pygmaeus fed one of two egg yolk-based artificial diets was compared with that of nymphs fed E. kuehniella eggs. Despite their lower body weights, preda- tors produced on either artificial diet killed similar numbers of prey as their counterparts reared on lepidopteran eggs. Our study indicates that artificial rearing systems may be useful to further rationalize the production of this economically important biological control agent.展开更多
Biological control of agricultural pests relies on knowledge of agroecosystem functionality, particularly when affected by the use of mass-produced biological agents. Incorporating pre- and/or post-release information...Biological control of agricultural pests relies on knowledge of agroecosystem functionality, particularly when affected by the use of mass-produced biological agents. Incorporating pre- and/or post-release information such as genetic diversity and struc- ture on these agents using molecular-based approaches could advance our knowledge of how they perform in agroecosystems. We evaluated the population genetics of Macrolo- phus pygmaeus, the most widely used predatory mirid against many arthropod pests of greenhouse crops in the Mediterranean region, using the mitochondrial Cytb sequence and microsatellite data, and population genetics and phylogeny approaches. We investigated commercially mass-produced insects (i.e., commercial insects either mass-reared in the laboratory for many generations, or purchased by farmers and released in the greenhouses) and "wild" insects (i.e., that occur naturally outside or are collected in nature for release in the greenhouses). The mirids were mainly collected in agroecosystems in which solana- ceous plants are grown in northern Spain, southern France and Greece. Both molecular markers and approaches distinguished 2 genetically differentiated populations. The less genetically diverse population, hereafter named the "commercial" strain included all indi- viduals from laboratory mass-rearings and most releases of commercially bred individuals. The most genetically diverse population mainly comprised individuals originating from noncultivated environments, or from releases of"wild" individuals. Rare examples of hy- bridization between M. pygmaeus from the 2 populations were observed and asymmetric gene flow was revealed. These findings provide new insights into what happens to M. pyg- maeus released in the agroecosystems we studied, and show that it is possible to monitor some commercial strains.展开更多
Development of conservation biological control programs requires the identifi-cation of sources that contribute to predator colonization of crops.Macrolophus pygmaeus(Rambur)(Hemiptera:Miridae)is an efficient polyphag...Development of conservation biological control programs requires the identifi-cation of sources that contribute to predator colonization of crops.Macrolophus pygmaeus(Rambur)(Hemiptera:Miridae)is an efficient polyphagous predator used in biological con-trol programs in vegetable crops in Europe.We have developed a marking method based on spraying with a solution of the brine shrimp Artemia spp.(Anostraca:Artemidac)cysts,followed by a PCR detection of Artemia DNA to monitor M.pygmaeus dispersal from banker plants to tomato crops.Experiments conducted in climatic chambers show that the topical application of this marking solution on M.pygmaeus does not significantly reduce adult longevity and that it is detected up to 6 d after the application.When this Artemia solution was applied on Calendula officinalis L.banker plants harboring M.pygmaeus and maintained outdoors,Artemia DNA was still detected on 62%of the insects after6 d.The conducted field applications in commercial greenhouses have confirmed the usefulness of this method to monitor M.pygmaeus dispersal from banker plants to a newly planted tomato crop.This method can be used to assess arthropod movement,being an interesting molecular approach for further improving future pest management strategies.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 31870595No. 32001292)Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)。
文摘As a woody grass,bamboo has special reproductive habits with an extremely long vegetative phase.Pleioblastus pygmaeus is a kind of ornamental dwarf bamboo species with high ecological and economic value in China.There was no documentary record of the flowering of P.pygmaeus until 2015,which bloomed in the Bamboo Garden of Nanjing Forestry University.Generally,bamboo plants rarely bear fruit or have a low seed setting rate,but this species has a high seed production.This study explores developmental reasons using anatomical methods.The process of flower bud differentiation and a series of important reproductive development processes including anther wall development,microsporogenesis,megasporogenesis,male and female gametophyte development,and embryonic development were investigated sequentially.Each stamen contained three tetrasporangiate anthers and the development of anther wall was of Monocotyledonous type.The microspores finally matured into 3-celled pollen grains by two successive mitoses.The pistil was composed of three carpels,with an anatropous,tenuinucellate and bitegmic ovule in a single ovary.The formation of embryo sac belonged to Polygonum type.With three mitoses,functional megaspore developed into the embryo sac with eight nuclei within seven cells.The development of stamen and pistil was synchronous in the same floret.The development of embryo followed Grass type and the development of endosperm belonged to Nuclear type.The development of endosperm was earlier than that of embryo.The study enriches basic knowledge of reproductive biology of bamboo plants and is of great fundamental significance to furtherly explore flowering mechanism of P.pygmaeus and to cultivate bamboo plants sustainably.
文摘The biological parameters of Macrolophus pygmaeus Rambur afler prolonged rearing in the absence of plant materials were compared with those of conventionally plant-reared predators. When eggs of Ephestia kuehniella Zeller were provided as food, developmental and reproductive fitness of M. pygmaeus reared for over 30 consecutive generations using artificial living and oviposition substrates was similar to that of predators kept on tobacco leaves. Plantless-reared fifth instars of the predator also had similar predation rates on second instars of the tobacco aphid, Myzus persicae nicotianae Blackman, as their peers maintained on plant materials. In a further experiment, predation on aphid prey by fifth instar M. pygmaeus fed one of two egg yolk-based artificial diets was compared with that of nymphs fed E. kuehniella eggs. Despite their lower body weights, preda- tors produced on either artificial diet killed similar numbers of prey as their counterparts reared on lepidopteran eggs. Our study indicates that artificial rearing systems may be useful to further rationalize the production of this economically important biological control agent.
文摘Biological control of agricultural pests relies on knowledge of agroecosystem functionality, particularly when affected by the use of mass-produced biological agents. Incorporating pre- and/or post-release information such as genetic diversity and struc- ture on these agents using molecular-based approaches could advance our knowledge of how they perform in agroecosystems. We evaluated the population genetics of Macrolo- phus pygmaeus, the most widely used predatory mirid against many arthropod pests of greenhouse crops in the Mediterranean region, using the mitochondrial Cytb sequence and microsatellite data, and population genetics and phylogeny approaches. We investigated commercially mass-produced insects (i.e., commercial insects either mass-reared in the laboratory for many generations, or purchased by farmers and released in the greenhouses) and "wild" insects (i.e., that occur naturally outside or are collected in nature for release in the greenhouses). The mirids were mainly collected in agroecosystems in which solana- ceous plants are grown in northern Spain, southern France and Greece. Both molecular markers and approaches distinguished 2 genetically differentiated populations. The less genetically diverse population, hereafter named the "commercial" strain included all indi- viduals from laboratory mass-rearings and most releases of commercially bred individuals. The most genetically diverse population mainly comprised individuals originating from noncultivated environments, or from releases of"wild" individuals. Rare examples of hy- bridization between M. pygmaeus from the 2 populations were observed and asymmetric gene flow was revealed. These findings provide new insights into what happens to M. pyg- maeus released in the agroecosystems we studied, and show that it is possible to monitor some commercial strains.
基金Thanks to Marta Ramirez for technical support,Montse Matas(ADV Baix Maresme)for her support in pro-viding and managing the greenhouses used and Dr.Priscila Gomez-Polo for her suggestions.This study has been funded by the Spanish Ministry of Economy and Competitiveness(MINECO)(Projects AGL2008-00546,AGL2011-24349 and AGL2014-53970-C2-2-R).Funding acknowledgment also to the CERCA Pro-gramme/Generalitat de Catalunya.
文摘Development of conservation biological control programs requires the identifi-cation of sources that contribute to predator colonization of crops.Macrolophus pygmaeus(Rambur)(Hemiptera:Miridae)is an efficient polyphagous predator used in biological con-trol programs in vegetable crops in Europe.We have developed a marking method based on spraying with a solution of the brine shrimp Artemia spp.(Anostraca:Artemidac)cysts,followed by a PCR detection of Artemia DNA to monitor M.pygmaeus dispersal from banker plants to tomato crops.Experiments conducted in climatic chambers show that the topical application of this marking solution on M.pygmaeus does not significantly reduce adult longevity and that it is detected up to 6 d after the application.When this Artemia solution was applied on Calendula officinalis L.banker plants harboring M.pygmaeus and maintained outdoors,Artemia DNA was still detected on 62%of the insects after6 d.The conducted field applications in commercial greenhouses have confirmed the usefulness of this method to monitor M.pygmaeus dispersal from banker plants to a newly planted tomato crop.This method can be used to assess arthropod movement,being an interesting molecular approach for further improving future pest management strategies.