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The predatory bug Orius sauteri (Poppius) (Hemiptera: Anthocoridae) is an important biological control agent in Asia that is often released on field crops and in greenhouses to control pests on vegetable and ornamental plants. This study compared the developmental and reproductive performance of O. sauteri on monotypic diets of four aphid species, western flower thrips, and two-spotted spider mite. Thrips emerged as the optimal prey type, consistent with findings for many other Orius spp. A diet of Frankliniella occidentalis (Pergande) yielded the fastest development, largest adult body size, shortest pre-oviposition period, and highest fecundity and longevity. Tetranychus urticae (Koch) was the next most suitable prey by most performance measures. Among aphids, Myzus persicae (Sulzer) was the most suitable and Aphis gossypii Glover the least suitable, with Aphis craccivora Koch and Megoura japonica (Matsumura) intermediate. Female O. sauteri were larger than males and female body mass varied more with prey type than did that of males. Despite the variation in performance among prey, all prey species yielded equally good juvenile survival and none would be expected to negatively impact the numerical response of O. sauteri in biological control applications where these arthropods form part of the prey complex.

Exotic vascular plants are increasingly numerous, and decision support systems identifying the most problematic species are needed to help environmental managers to develop control strategies. The fundamental tool in this respect is a list of weeds, or a weed risk assessment. We propose here a list for the province of Quebec constructed using an innovative approach based on 1) well-defined criteria, 2) consideration of all potential problems associated with exotic plants, 3) use of credible scientific data, 4) assessment by a panel composed of experts with diverse expertise and who are also potential users of the list, 5) use of a decision support approach, and 6) a debate among experts in order to reach a verdict concerning the status (weed, no weed) of each candidate plant. The list contains 87 of the 908 taxa of exotic vascular plants that are naturalized in Quebec, i.e., 9.6% of the total. About two thirds of the weeds are problematic for agricultural or ornamental plant production or for forestry; the others are, in decreasing numerical order, problematic for biodiversity or natural ecosystem functions, health, landscaping or home gardening, and recreational activities. Evaluating the threat posed to biodiversity by individual species was a challenge, because few relevant studies have been published. The use of well-defined criteria greatly reduced (by a factor of 3) the number of weed species from an initial list based on individual uncensored expert opinions. The resulting list is not definitive, and should be used with caution. However, we estimate that our approach is more rigorous than the other qualitative approaches developed to date, with performance that matches the semi-quantitative or quantitative tools frequently used for assessing invasive plants, such as the Australian Weed Risk Assessment.

Exotic vascular plants are increasingly numerous, and decision support systems identifying the most problematic species are needed to help environmental managers to develop control strategies. The fundamental tool in this respect is a list of weeds, or a weed risk assessment. We propose here a list for the province of Quebec constructed using an innovative approach based on 1) well-defined criteria, 2) consideration of all potential problems associated with exotic plants, 3) use of credible scientific data, 4) assessment by a panel composed of experts with diverse expertise and who are also potential users of the list, 5) use of a decision support approach, and 6) a debate among experts in order to reach a verdict concerning the status (weed, no weed) of each candidate plant. The list contains 87 of the 908 taxa of exotic vascular plants that are naturalized in Quebec, i.e., 9.6% of the total. About two thirds of the weeds are problematic for agricultural or ornamental plant production or for forestry; the others are, in decreasing numerical order, problematic for biodiversity or natural ecosystem functions, health, landscaping or home gardening, and recreational activities. Evaluating the threat posed to biodiversity by individual species was a challenge, because few relevant studies have been published. The use of well-defined criteria greatly reduced (by a factor of 3) the number of weed species from an initial list based on individual uncensored expert opinions. The resulting list is not definitive, and should be used with caution. However, we estimate that our approach is more rigorous than the other qualitative approaches developed to date, with performance that matches the semi-quantitative or quantitative tools frequently used for assessing invasive plants, such as the Australian Weed Risk Assessment.

An investigation was conducted on the number and morphology of the chromosomes of four species from the family Commelinaceae: Spironema fragrans Lindl., Setcreasea purpurea Boom, Tradescantia albiflora Kunth. and Tradescantia blossfeldiana Mildbr.

Les plantes vasculaires exotiques étant toujours de plus en plus nombreuses, il importe de développer des outils qui aideront les gestionnaires de l'environnement à identifier les espèces les plus problématiques. L'outil de base en la matière est une liste des plantes nuisibles. Dans cet article, nous proposons une liste pour le Québec constituée grâce à une approche qualitative innovante basée sur 1) l'adoption de critères d'évaluation explicites, 2) la prise en compte de l'ensemble des types de nuisance, 3) l'utilisation de données scientifiques crédibles, 4) la constitution d'un panel d'experts diversifié comprenant des utilisateurs potentiels de la liste, 5) l'encadrement des membres du panel par une approche d'aide à la décision et 6) l'instauration du débat pour l'évaluation du caractère nuisible des plantes. Au total, 87 des 908 taxons de plantes vasculaires exotiques naturalisées au Québec ont été retenus par le panel d'experts comme plantes nuisibles, soit 9,6 % de l'ensemble. Les deux tiers des plantes désignées comme nuisibles le sont, à des degrés divers, pour les productions agricoles, horticoles ou forestières. Suivent, dans l'ordre, les nuisances pour la biodiversité ou le maintien des fonctions écosystémiques, celles pour la santé, celles pour l'horticulture ornementale ou l'aménagement paysager et celles pour les activités de loisir. Il a été difficile de statuer sur la nuisance pour la biodiversité, la plupart des espèces exotiques n'ayant pas fait l'objet d'études approfondies à cet égard. En définitive, l'adoption de critères faisant consensus a eu pour effet de réduire fortement (presque par un facteur de 3) le nombre de taxons d'une liste qu'on aurait pu constituer à partir d'opinions d'experts sollicitées sur une base individuelle, sans critères précis. Bien que cette liste ne soit pas définitive et qu'elle doive être interprétée avec prudence, nous croyons que l'approche proposée ici est supérieure, quant à sa rigueur, aux autres approches qualitatives développées à ce jour et que sa performance est au moins équivalente à celle des approches semi-quantitatives ou quantitatives fréquemment utilisées, comme le Australian Weed Risk Assessment.

The aim of this study was to establish a protocol for in vitro regeneration and multiplication of Cymbidium pendulum through protocorms, as explants using organic growth supplements such as banana homogenate, coconut water, and peptone. The effect of growth supplements was tested on multiplication (neo-formation of secondary protocorms from primary protocorms) of protocorms, development of maximum number of shoots and early plantlets in M medium (Mitra medium). Though the explants regenerated in the absence or presence of growth adjuncts in the medium; the regeneration frequency was found significantly higher in organic growth supplement-enriched medium than control. The protocorm segments (primary) regenerated into protocorm-like bodies (secondary protocorms) which eventually differentiated into shoots; no intervening callus stage was observed. Among the treatments, the highest regeneration frequency, robust shoots and root formation was recorded in banana homogenate (50 g/L); the roots were lengthy, thick, and covered all over the surface by root hairs. Higher concentration of banana homogenate (75 g/L) proved detrimental for the survival of cultures; the protocorm-like bodies showed necrosis and they perished soon after. Coconut water (10%) and peptone (2 g/L) supplemented medium proved optimum for profuse multiplication of protocorm-like bodies. The treatments with organic growth supplements gave better and early plantlets as compared to control. Peptone (2 g/L) and coconut water (10%) proved beneficial for multiplication of regenerants, maximum number of shoots formation and early plantlet development; whereas banana homogenate (50 g/L) favoured the highest regeneration frequency and healthy growth of plantlets.

Herbicides play an important role in the production of nursery crops by reducing weed problems and improving production efficiency. Herbicides applied to nursery crops may move in runoff water into retention basins, which are used to irrigate container plants. Studies investigated the growth and development of containerized landscape plants subjected to irrigation water containing herbicide residues. Containerized dwarf gardenia, Snow azalea, Buccaneer azalea, Hellers Japanese holly, fountain grass, and daylily were grown in fine pine bark medium in the greenhouse and were irrigated with water containing 1 mg/L and 10 mg/L of oryzalin, oxyfluorfen, and isoxaben. Fountain grass and daylily were the most sensitive to herbicide application with reduced root and shoot growth. Oryzalin was the most phytotoxic to fountain grass followed by oxyfluorfen and isoxaben. Oryzalin and oxyfluorfen at 10 mg/L reduced the growth index of fountain grass. Oryzalin was the most phytotoxic herbicide to daylily, followed by isoxaben and oxyfluorfen. Only the high rate (10 mg/L) of oryzalin reduced the growth index of daylily. Among woody species, the root weights of Hellers holly were reduced by 10 mg/L of isoxaben. The growth of other woody species was not affected by the herbicides.

This study reports on the effect of two arbuscular mycorrhizal fungi (Glomus mosseae and Acaulospora laevis) applied either alone or in combination on post-transplanting performance of micropropagated Spilanthes acmella. Complete plantlets of S. acmella were raised by direct organogenesis from nodal explants on Murashige and Skoog medium supplemented with various cytokinins. S. acmella plantlets responded to all three mycorrhizal treatments in a significantly different way. G. mosseae enhanced the survival rate of S. acmella plantlets to 100%. Plant height, plant spread, number of branches per plant, number of leaves per plant, leaf area, biomass production, and chlorophyll content were significantly higher in AM inoculated plantlets as compared to the uninoculated ones. This clearly demonstrates that AM inoculation improved not only the survival rate of micropropagated plantlets but also their growth and biomass yield.

India has a diverse agroclimate representing tropical, subtropical and temperate climates with zones ranging from average to high in temperature, humidity and rainfall; from low to scarce rainfall in deserts to cold to very cold plains and upland areas. Thus it is the home of one of the richest flora and fauna in the world. For pests and pathogens, too, tropical and subtropical climates are ideal for growth and development. A majority of the world's fruits, vegetables, cereals, pulses, oil seed crops, fiber crops, sugarcane, spices, and ornamentals are cultivated in India. Virus diseases and their vectors are also in abundance. Since ancient times, virus-like diseases and management practices have been known in India. This knowledge has now been revived and adopted in organic farming, especially for medicinal and aromatic plants. Current trends for extensive and intensive agriculture, open international agricultural trade, and thus food security and sustained economy have brought new challenges in the fight against virus diseases. In this changing scenario, current diseases of significance are caused by begomoviruses, badnaviruses, cucomoviruses, potyviruses, ilarviruses in crops such as vegetables, fruits, ornamentals, fiber crops, and sugarcane. Variability in the viruses is also common. Briefly reviewed here is the positive effect of an isolate of Rice necrosis mosaic virus; when artificially inoculated on jute and mesta fiber crops enhanced their fiber contents. Diseases of significance, e.g., leaf fleck disease of sugarcane, citrus yellow mosaic disease, banana bunchy top, banana bract mosaic, mungbean yellow mosaic, mosaic in chrysanthemum, gladiolus and orchids are also discussed. Efficient, reliable diagnostic tools have been developed and used extensively. Some of the advanced laboratories have been accredited for virus indexing under the National Certification System for tissue-cultured plants. International standards for phytosanitary measures have been promulgated, and a mandatory nodal agency is in place for the conservation and exchange of germplasm; a Containment Level-4 facility to examine incoming transgenics and a fully equipped laboratory to intercept virus-infected plant material are functional. A National Agricultural Biosecurity System will soon be in place. All these measures are essential to protect agricultural systems and to compete in the international agriculture market. Continued vigilance, disease mapping and adopting the latest technology are required to practice sustainable agriculture.