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Flowering plants have been widely used to enhance biological control. However, this approach has been limited to some extent by the lack of suitable flowering plant species of wide applicability, particularly for global pests. A key example is the green peach aphid, Myzus persicae (GPA). It is commonly attacked by the polyphagous koinobiont aphidiidae, Aphidius colemani, which is also of global occurrence. Here, eight flowering plants were evaluated for the potential enhancement of GPA biological control using A. colemani under laboratory conditions. These included buckwheat (Fagopyrum esculentum), alyssum (Lobularia maritima), white rocket (Diplotaxis erucoides.), wild mustard (Sinapis arvensis), lavender (Lavandula angustifolia), wild marjoram (Origanum vulgare), thyme (Origanum marjorana) and pepper mint (Mentha piperita). The effects of access to these flowers on the longevity (days), potential fecundity (number of dissected eggs) and parasitism rate for A. colemani compared with the control treatment (water) were studied. Longevity of A. colemani which had access to buckwheat was 4–5 times longer than the control and 2–3 times longer than it was in the other plant treatments; the latter did not differ significantly between each other. Potential fecundity of A. colemani was the highest when it had been provided with buckwheat flowers. Exposing A. colemani to flowering plants for longer time intervals (12 hr and 24 hr) increased the number of eggs produced compared with 6 hr. The number of parasitized aphids/female A. colemani with buckwheat flowers was the highest of all treatments; it ranged from 14 in the control to 219 with buckwheat. Further studies should be carried out under field conditions to determine the effect of a range of flowering plants on A. colemani. For example, although buckwheat was highly effective, in many climates it may be a useful component in mixtures comprising other, more robust species.

The adoption of agro-ecological practices in agricultural systems worldwide can contribute to increased food production without compromising future food security, especially under the current biodiversity loss and climate change scenarios. Despite the increase in publications on agro-ecological research and practices during the last 35 years, a weak link between that knowledge and changed farmer practices has led to few examples of agroecological protocols and effective delivery systems to agriculturalists. In an attempt to reduce this gap, we synthesised the main concepts related to biodiversity and its functions by creating a web-based interactive spiral (www.biodiversityfunction.com). This tool explains and describes a pathway for achieving agro-ecological outcomes, starting from the basic principle of biodiversity and its functions to enhanced biodiversity on farms. Within this pathway, 11 key steps are identified and sequentially presented on a web platform through which key players (farmers, farmer networks, policy makers, scientists and other stakeholders) can navigate and learn. Because in many areas of the world the necessary knowledge needed for achieving the adoption of particular agro-ecological techniques is not available, the spiral approach can provide the necessary conceptual steps needed for obtaining and understanding such knowledge by navigating through the interactive pathway. This novel approach aims to improve our understanding of the sequence from the concept of biodiversity to harnessing its power to improve prospects for 'sustainable intensification' of agricultural systems worldwide.

Vineyards worldwide occupy over 7 million hectares and are typically virtual monocultures, with high and costly inputs of water and agro-chemicals. Understanding and enhancing ecosystem services can reduce inputs and their costs and help satisfy market demands for evidence of more sustainable practices. In this New Zealand work, low-growing, endemic plant species were evaluated for their potential benefits as Service Providing Units (SPUs) or Ecosystem Service Providers (ESPs). The services provided were weed suppression, conservation of beneficial invertebrates, soil moisture retention and microbial activity. The potential Ecosystem Dis-services (EDS) from the selected plant species by hosting the larvae of a key vine moth pest, the light-brown apple moth (Epiphyas postvittana), was also quantified. Questionnaires were used to evaluate winegrowers’ perceptions of the value of and problems associated with such endemic plant species in their vineyards. Growth and survival rates of the 14 plant species, in eight families, were evaluated, with Leptinella dioica (Asteraceae) and Acaena inermis ‘purpurea’ (Rosaceae) having the highest growth rates in terms of area covered and the highest survival rate after 12 months. All 14 plant species suppressed weeds, with Leptinella squalida, Geranium sessiliforum (Geraniaceae), Hebe chathamica (Plantaginaceae), Scleranthus uniflorus (Caryophyllaceae) and L. dioica, each reducing weed cover by >95%. Plant species also differed in the diversity of arthropods that they supported, with the Shannon Wiener diversity index (H′) for these taxa ranging from 0 to 1.3. G. sessiliforum and Muehlenbeckia axillaris (Polygonaceae) had the highest invertebrate diversity. Density of spiders was correlated with arthropod diversity and G. sessiliflorum and H. chathamica had the highest densities of these arthropods. Several plant species associated with higher soil moisture content than in control plots. The best performing species in this context were A. inermis ‘purpurea’ and Lobelia angulata (Lobeliaceae). Soil beneath all plant species had a higher microbial activity than in control plots, with L. dioica being highest in this respect. Survival proportion to the adult stage of the moth pest, E. postvittana, on all plant species was poor (<0.3). When judged by a ranking combining multiple criteria, the most promising plant species were (in decreasing order) G. sessiliflorum, A. inermis ‘purpurea’, H. chathamica, M. axillaris, L. dioica, L. angulata, L. squalida and S. uniflorus. Winegrowers surveyed said that they probably would deploy endemic plants around their vines. This research demonstrates that enhancing plant diversity in vineyards can deliver SPUs, harbour ESPs and therefore deliver ES. The data also shows that growers are willing to follow these protocols, with appropriate advice founded on sound research.

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